Poplar culture in India

Ramesh Dhiman

The main poplar culture in India, is happening towards south of the Himalayan foothills in the north western region of the country and is based on around two dozen Populus deltoides clones. Trees are grown on largely farm lands along with assorted agricultural crops having endemic and widespread acceptance in the region of poplar culture. Published reports indicate very high timber productivity up to 59 cum/ha/year and good plantations grow at the average rate of 5 m in height and 5 cm in diameter per annum over a short rotation of 6-7 years. The current annual increment (CAI) and mean annual increment (MAI) for height, diameter and volume growth of good growing plantations culminate between 3 to 4 years and these plantations are harvested at a very young age i.e., 3 years on ward based on market conditions, demand and supply of its wood and farmer's need for money from tree sale. The Important stimulators contributing towards such a high productivity of poplar plantations include its culture in warm and humid geographical locations towards the low latitudinal limits of the natural distribution of the species, regular development and replacement of old cultivars with the site matched productive ones, innovative nursery production system to maintain quality of the planting stock, intensive cultural inputs including repeated soil working, surface irrigation, nutritional application for intercrops those are also available for poplar, and tending operations. Poplar culture is synchronized with soil working just near the planting time so that saplings on field planting get fast rooting, sprouting and growth. Maintenance of planting stock in juvenile stage and in full turgid conditions just before field planting and flood irrigation immediately after planting results in acceptable performance attributes of higher survival and better early growth. Repeated soil working of fields for agricultural crops grown inside poplar plantations helps in developing fibrous root system around the availability of growth inputs near the surface far their best utilization. Tending operations viz., removal of side buds of saplings for unwanted shoot growth, lateral and vertical pruning are also important stimulators to improve the qualitative growth. The paper summarizes the standard package and practices from regular development of cultivars to quality planting stock production, field planting, cultural and tending operations including preferred agricultural crops grown therewith which together contribute towards high productivity of poplar plantations.

Poplar (Populus deltoides W. Bartram ex Marshall) is an important agro-forestry tree in Pakistan due to its fast growing nature and high economical value. The objectives of this study were to determine the growth patterns and appropriate selling time of Poplar. Growth and price curves of the tree of different ages were worked out by collecting data about height and DBH (Diameter at Breast Height) of Poplar from different villages of Faisalabad district. About 1000 trees of 2 to 10 years age were selected for collection of the data during field survey. Data revealed that Poplar trees grew in height rapidly for the first 5 years as it achieved about 80% of its 10 years total height within initial 5 years. Similarly, DBH of the trees increased rapidly with more or less constant rate from 2 to 8 years, later on the increment was found very low and constant up to 10th year. Cambial surface area per tree increased rapidly (10.5m2/year) during most of its life span excluding last 2 to 3 years. Prices of the trees did not increased in proportion to tree volume per year and it was found that tree should be harvested during early years (even before 8 year) for more income.

A questionnaire survey was conducted during April- May 2016 on poplar based agroforestry model in Vaishali district of Bihar for analysis of its acceptability, profitability, and constraints prominent for the popular beyond its favourable condition. Result released that the growth of popular not much affected but on comparison of production and income obtained from with and without cultivation of poplar trees, with crops shows slightly decrease in production of crops but overall income of farmer’s increases due to addition of poplar selling price. The yield of potato and onion found better as compared to the other crops while the yield of maize was lower with Poplar. Based on the respondent opinion, 46.14% of the respondents believe that trees reduce yield of agriculture crop. Other reasons behind less popularity of agroforestry include lack of market (38.57%), small land holding (31.71%), lack of awareness (25.71%), late returns (26.57%) and restrictions on felling and transport of...

ENVIS For e st r y Bulle t in Vol. 12, No. 1 Year 2012 Poplars in India Commemorating 24th Session of International Poplar Commission at Forest Research Institute, Dehradun (India) 29th October - 2nd November 2012 ENVIS CENTRE ON FORESTRY FOREST RESEARCH INSTITUTE (INDIAN COUNCIL OF FORESTRY RESEARCH AND EDUCATION) DEHRADUN ENVIS Forestry Bulletin Poplars in India Patrons Dr. V.K. Bahuguna Director General, ICFRE Dr. P.P. Bhojvaid Director, FRI Editors Shailendra Kaushik Y.P. Singh Dinesh Kumar Manisha Thapliyal Santan Barthwal Guest Editor R.C. Dhiman Compilation Vandana Uniyal Ritu Negi Designing and Assistance Ruchi Gupta All communications and suggestions may be addressed to: The Editor, ENVIS Forestry Bulletin, ENVIS Centre on Forestry National Forest Library and Information Centre Forest Research Institute, P.O. New Forest Dehradun - 248 006 Phone: (0135) 2756414, 2224845 E-mail: kaushiks@icfre.org; kaushikshail@yahoo.com Published by The Chief Librarian on behalf of ENVIS Centre on Forestry National Forest Library and Information Centre Forest Research Institute, Dehradun - 248 006 Note: This Bulletin does not necessarily reflect the views of the Ministry of Environment and Forests, Government of India, and the ENVIS Centre on Forestry. Message The genus Populus, consisting of more than 30 species, occurs throughout the forests of temperate and cold regions of northern hemisphere between the southern limit of around 300 N and northern limit of latitude 450N. Out of them, Populus ciliata, P. alba, P. euphratica, P. gamblii, P. jacquemontii var. glauca and P. rotundifolia are considered indigenous to India. Due to increased demand of timber for wood based industries, in 1950s, a large number of exotic clones like G3, G48, etc. of poplars were introduced in the country, mainly for increasing the wood availability for match, composite board, plywood and sport goods industries. Populus deltoides Marsh is an important commercial timber species, used for match stick, veneer and pulpwood. Forest Research Institute, Dehradun (FRI) has been one of the key institutions for introduction of poplar clonal material from USA and Australia. Poplar cultivation in India received a boost with the introduction of fast-growing P. deltoides clones from abroad. Later more introductions were made by FRI, State Forest Department of Uttar Pradesh, particularly Haldwani centre, which is now in Uttarakhand, WIMCO and Dr. Y.S. Parmar University of Horticulture and Forestry, Solan, Himachal Pradesh. Poplars are most preferred tree species for the purpose of agroforestry by the farmers. Many clones of exotic poplars are cultivated in Punjab, Haryana, Uttarakhand, Uttar Pradesh as well as lower parts of Himachal Pradesh, and Jammu and Kashmir. Indian Council of Forestry Research and Education (ICFRE) has been working on popularization of poplar cultivation in plains of Uttar Pradesh and Bihar. In Vaishali District of Bihar (latitude 250 41’ N and longitude 85013’E), which is well beyond the normal distribution range of poplars, planting of 6.1 million poplar seedlings on the farmland of more than a thousand villages is planned under Bihar Project, sponsored by the Planning Commission, Govt. of India, through its Forest Research and Extension Centre (FREC), Patna. Poplar plays an important role in rural development by generating employment to many categories of skilled, semi skilled and unskilled workers and, thus, helps in achieving the Millennium Goal of poverty alleviation laid down by the Food and Agriculture Organization (FAO). Poplar cultivation has become an important source of livelihood and prosperity, encouraging more and more farmers to grow poplars in agroforestry model. Research institutes under ICFRE have been extending helping hand to the growers. Poplars generate remunerative and much higher consolidated returns than the normal agricultural crop rotations, thereby, assuring security against crop failures due to extreme climatic conditions. It is a viable option for the rural economy of India. (V.K. Bahuguna) Message I am deeply honored by this opportunity to commemorate the achievements of poplar research and cultivation in India with the launching of the new publication ‘Poplars in India’ on the occasion of the 24th Session of the International Poplar Commission in Dehradun. As Chairman of the International Poplar Commission (IPC) I would like to congratulate the Indian Council of Forestry Research and Education (ICFRE) and the Forest Research Institute (FRI) on this memorable work coupled with the wish that this important publication will have a wide distribution among the members of the international poplar community. In India, poplars are the most popular tree species in agroforestry production systems where they are intercropped with agricultural crops like wheat, sugarcane, paddy and shade-tolerant fodder crops due to their fast growth, outstanding properties and quick and high financial returns. Smallholders and farmers own an increasing area of poplar plantations and depend on them for the improvement of their livelihoods. A large number of people, among them many women, gain employment and income from poplar cultivation, particularly in remote areas where forestry and agroforestry are the only economically viable land use options. Timber from poplars often forms the backbone for the development of vibrant plywood, composite board, match, paper and sports goods industries, which further contribute to the improvement of rural livelihoods, especially when a significant portion of the wealth of such value-added activity remains in the local economy and among the forest-dependent workforce. India is a long-term member of the IPC which was founded in 1947 with a view to supporting the reconstruction of rural and industrial economies. It has become a statutory body of FAO in 1959 and has since increased its membership to the current number of 37 countries. For the past 65 years, the IPC, through National Poplar Commissions, Working Parties and the Sub-Committee on Nomenclature and Registration has provided a bridge linking research of poplar and willow cultivation, conservation and utilization with development policies, planning and implementation practices. IPC through its member countries has also promoted the organization of international conferences and meetings combined with field-study tours on poplar and willow culture. In this context the Indian Council of Forestry Research and Education (ICFRE) and the Forest Research Institute (FRI) in Dehradun have embraced to host the 24th Session of IPC in 2012, for which I wish to express my sincere gratitude. I am convinced that this event will mark a significant milestone in the history of the International Poplar Commission. Stefano Bisoffi Chairman of the International Poplar Commission (IPC) Rome, October 2012 CRA | via Nazionale, 82 – 00184 Roma T +39-06-478361 | F +39-06-47836320 W www.entecra.it | @ cra@entecra.it C.F. 97231970589 FOREST RESEARCH INSTITUTE Dr. P.P. BHOJVAID, I.F.S. (Indian Council of Forestry Research and Education) (An autonomous body of Ministry of Environment and Forests, Govt. of India) P.O. New Forest, Dehradun – 248 006 Director, FRI and Vice Chancellor, FRI Deemed University Dated: 19.10. 2012 Message Introduction of poplar (Populus spp.) as an agroforestry species in the states of Punjab, Haryana and western Uttar Pradesh has undergone three distinct phases: Initially, during 1970s and mid 1980s, the farmers were skeptical in adopting the cultivation of poplars on their farmlands. However, the government plantations demonstrated that poplar having shorter rotation (5-8 years) could be grown successfully in combination with many agricultural and cash crops without substantially reducing their yield. This demonstration motivated large progressive and absentee farmers for growing poplars on their farmlands. The development of poplar based industries such as plywood, pencil making, packaging boxes and the depression in market prices of Eucalyptus in the 1980s resulted in switching over from Eucalyptus to poplar plantations by majority of farmers in these states. In the recent past, the practice of cultivation of poplars in private farms under agroforestry has become a passion even with small and marginal farmers who saw it as a potential source of additional income. Consequently, one comes across a mosaic of large blocks of poplar plantations from 2,000 to 10,000 trees and smaller plantations raised as boundary rows of about 50-100 trees scattered over an otherwise agricultural dominant landscape. It is well known that poplar now contributes significantly to people and livelihood through the provision of wood, wood products, non-wood products, environmental and social services in India. The Forest Research Institute at Dehradun, through its research professionals, has strived to develop agroforestry models of poplar. Subsequently, the institute has also worked on other aspects, such as botany, silviculture, pathology and entomology, economics and policy issues involved in the cultivation of poplar by Indian farmers and the state forest departments. Similarly, the work done by the professionals at the institute on clonal development with respect to this species has been commendable. The ENVIS Centre on Forestry at the National Forest Library and Information Centre has put together important issues related to poplar culture in India in the commemorate issue of ENVIS Forestry Bulletin to be released on the occasion of 24th Session of the International Poplar Commission. This occasion will bring all the stake-holders together to deliberate on the issues concerning poplar raising and utilization in 21st century. This publication is a comprehensive account of development of poplar and its spread in the northern states of the Republic of India. Consequently, the chapters will familiarize the readers with various aspects of nursery raising, plantation, upkeep, harvesting and utilization, etc. of poplar in India. The publication also touches upon the role of poplar as mitigation alternative in the light of phenomenon of climate change. I congratulate the editors of the bulletin who have taken responsibility to develop the manuscript and bring out this important document. (P.P. Bhojvaid) ENVIS Forestry Bulletin Vol. 12 No. 1 2012 Contents Editorial Indian poplars with special reference to indigenous species H.B. Naithani and S. Nautiyal 1 Status of poplar introduction in India Dinesh Kumar and N.B. Singh 9 Status of poplar culture in India R.C. Dhiman 15 Status of poplar breeding in India with special reference to work done at Dr. Y.S. Parmar University of Horticulture and Forestry D.K. Khurana 33 Clonal development and diversity in WIMCO’s poplar programme R.C. Dhiman and J.N. Gandhi 40 Status of intercropping in poplar based agroforestry in India Sanjeev K. Chauhan, R. Sharma and W.S. Dhillon 49 Poplar culture on farmland: Farmer’s experience from Uttar Pradesh Nikki Pilania Chaudhary and Gaurav Chaudhary 68 Poplar culture for speedy carbon sequestration in India: A case study from Terai region of Uttarakhand Mohit Gera 75 Status of poplar diseases in India Y.P. Singh, Kartik Uniyal, Archana Bagwari, Kavita, Santan Barthwal, R.C. Dhiman and J.N. Gandhi 84 Fungal decay in poplar trees and wood N.S.K. Harsh 100 Status of insect pests of poplar in India with special reference to Clostero spp. Mukhtar Ahmad and Mohammad Faisal 105 Studies on wood quality of poplar Vimal Kothiyal 123 Status of anatomy and physical properties of wood in poplars P.K. Pande 132 Mapping research on poplar (Populus spp.) in ‘Forest Science Database’ Arundhati Kaushik, Ritu Negi, Santan Barthwal and Y.P. Singh 151 Research on poplars in India: A select bibliography (1997-2011) 157 Editorial Poplar culture in India is mainly dependent on indigenously developed and introduced clones of Populus deltoides. However, other common species cultivated in the country are P. alba, P. ciliata, P. gamblei and P. nigra. P. ciliata is generally planted in cold arid region of Jammu and Kashmir and Himachal Pradesh states, whereas P. gamblei is found in isolated pockets of a few eastern states. These species have been largely planted on forest and agricultural lands for diverse purposes. P. alba and P. nigra have been planted for centuries in the inner Himalayas for meeting the domestic tree based needs of fuel, fodder and small timber for local inhabitants in the vegetation deficit cold arid region. Around two dozen clones of P. deltoides are being grown in many locations in the poplar growing region that constitutes parts of Punjab, Haryana, Uttarakhnd, Uttar Pradesh and some adjoining states. The tree has recently been introduced by the Indian Council of Forestry Research and Education in Vaishali District of Bihar with the support of Planning Commission, Govt. of India. The tree has also been tried in almost all other states in the country but being a temperate species, its performance has not been found satisfactory in many of central and southern states. Because of its wide adaptability, P. deltoides has been extensively planted from the cold arid to the northwestern states of the country. It is mainly planted as a cash crop on agricultural fields in association with crops like sugarcane, wheat, fodder crops, medicinal plants, etc., generating remunerative returns of over Rs. 250,000 per hectare per year, which is an important factor for motivating growers to remain engaged with its culture. With over 300,000 hectares as present area under poplar culture, its role in rural development in terms of economic transformation, employment generation, industrial development and environment amelioration is huge. Research institutions, private sector and farming community together played an important role in making poplar cultivation a success story. Restrictions on green felling resulted in increased demand of alternative wood like ply woods and composite boards, which created great demand of indigenous raw material for these industries. As a result, cultivation of poplars became popular among farmers. Therefore, there was a boost in the poplar based agroforesry from Jammu and Kashmir to Uttar Pradesh. The idea of special issue of the ENVIS Forestry Bulletin was conceived to provide an exposure of the work done on poplars in India to the delegates of the 24th Session of International Poplar Commission being organized for the first time in the country at the Forest Research Institute, Dehradun. The issue includes inputs from the leading researchers about scientific advancements made on its anatomical studies, improvement, production, protection, usage, etc., poplar stake-holders, viz., private sector and farmers having a lot of practical experience on its culture. The issue first introduces the indigenous species of poplars with their taxonomical details and distribution. The story of diversity of poplars in India is completed with a word on the introduction of exotics. No introduction is successful unless production technology is perfected in the backdrop of ground realities. The article on breeding primarily confines on the efforts of Dr. Y.S. Parmar University of Horticulture and Forestry, Nauni, but provides a glimpse of overall approach for improvement that is further elaborated in the article on clonal forestry. Poplars in India are more popular as agroforestry crop, this aspect is dealt with in length in the article on intercropping in poplar based agroforestry. It is closely followed by the economics of the poplar culture and its carbon sequestration potential. These twin issues are core to the global market economy in the present context. The production target can never be achieved without a healthy crop and its byproducts, the article on diseases and insect pests address the health management of this commercially important tree. Some other relevant and emerging aspects of poplar culture in India, like wood quality and anatomical studies also find place in the issue. To capture the varied efforts involved in poplar culture, mapping of research on poplars also attempted, besides offering select bibliography of research on poplars in India during last one and half decade (1997-2011). It is hoped that the delegates and others will find this information useful to understand different dimensions of poplar culture in India. - Editors Indian Poplars with Special Reference to Indigenous Species H.B. Naithani and S. Nautiyal Botany Division, Forest Research Institute, Dehradun - 248 006 Introduction P There are four indigenous species of Populus namely P. ciliata, P. gamblei, P. jacquemontii var. glauca and P. rotundifolia found in the Himalaya. These species are important for cultivation in Himalayan zone and deserve attention for improvement Forestry Bulletin, 12(1), 2012 opulus and its ‘sister’ lineage, the genus Salix (willows), have been considered the only two genera in the Salicaceae family, although some taxonomists have included other genera, mostly from eastern Asia (Eckenwalder, 1996). More recently, however, the Flacourtiaceae family, the closest relative of Salicaceae, was re-classified, and a number of genera formerly included in Flacourtiaceae are now assigned to Salicaceae sensu lato, with in the Malpighiales order of the ‘Eurosid I’ clade (Chase et al., 2002; APG, 2003). Populus is the classical name of the poplar, others consider that this plant was used in ancient times to decorate public places in Rome where it is called ‘arbor populi’ ‘people’s tree’; i.e., Populus alba (Naithani et al., 2001). These plants are usually dioecious, rarely monoecious, viz., Populus lasiocarpa Oliv., native of western China (FAO, 1979). Exceptionally bisexual in P. jacquemontiana var. glauca, a species endemic to eastern Himalaya (Grierson and Long, 1983; Haines, 1906). Genus Populus Linn. includes 44 species in five sections. These are white poplars (Leuce), black poplars (Aigeiros), balsam poplars (Tecamahaca), Leucoides and Turanga. These are widely distributed in the temperate and subtropical regions of the Northern Hemisphere. In the plateaus of near-east and in the borderlands of Mediterranean Sea, since antiquity, people have being planting poplars near their homes, around their fields or along ditches and roads; these trees not only furnished fuel and timber for domestic use as well as forage to cattle but also provided shade, shelter and greenery in countries that would be otherwise. Realizing the importance of poplars, a National Poplar Commission was created in France in 1942 and, subsequently, an International Poplar Commission was set up under the aegis of the FAO during 1947. India became a member of this Commission in 1965 and constituted a National Poplar Commission with the objective of cultivation of poplars to meet the requirements of timber, fuel wood, etc. However, before the establishment of National Poplar Commission the cultivation of Poplar was traditional in Kashmir for a very long time and in recent years extended to Punjab, Haryana, Himachal Pradesh, Uttar Pradesh and on a very small scale, in West Bengal. Poplars, because of their fast rate of growth, high financial return and multiple utility, have become a very important species for cultivation both in the forest and farms. Poplar wood is widely used in plywood 1 and match splints. Market has been developed for poplar in Punjab, Haryana and Uttar Pradesh. With regard to the occurrence of poplar in India, Bor (1958) mentioned eight species, viz., P. alba Linn., P. euphratica Oliv., P. microcarpa Hook.f. and Th., P. nigra Linn., P. laurifolia Led. (P. balsamifera Linn.), P. ciliata Wall. ex Royle, P. gamblei Dode and P. jacquemontiana var. glauca Haines. There is controversy about the indigenous poplars in India. Many authors, viz., Tewari (1993), Singh and Kumar (1998) considered P. laurifolia, P. euphratica and P. alba as indigenous. In fact, many of them are exotic, viz., Sind poplar, bahan, bhan, padar (P. euphractica) has a remarkable geographical distribution. It occurs in Ladakh, plains of the Punjab and Sindh (Pakistan), Tibet; westwards it is indigenous on riverine areas in Afghanistan, Turkey, Iran, Iraq and Palestine, which exhibits a wide range of leaf polymorphism. P. alba and its cultivars known from southern Europe, western Siberia and Central Asia, were introduced and naturalized in Kashmir and Ladakh, known by the local name ‘Safeda’ and ‘Mal’. Black poplar (P. nigra) and its cultivars are native of temperate Europe, introduced in Kashmir, Himachal Pradesh and in some parts of Garhwal Himalaya. Balsam poplar (P. laurifolia Ledeb.) (P. balsamifera Linn.) a species of Central Asia, was planted in Leh (Ladakh), Lahaul and Spiti (Himachal Pradesh) and Tawang district of Arunachal Pradesh, where it is generally planted by the Buddhists near monasteries. Eastern cottonwood (P. deltoides) from North America is very commonly planted by the farmers in agroforestry plantations in Punjab, Haryana, Uttarakhand and Uttar Pradesh. A part of these P. x euramericana and P. x berolinensis were introduced in India in 1950. Clones of P. canescens, P. maximowiczii, P. trichocarpa, P. smonii, P. szechuanica, P. yunnanensis, etc. were introduced in the subsequent years. P. deltoides performed better than all other exotic poplars in the plains of North India, and relegated most other exotic poplars to the status of anonymity in India. In the hills, P. yunnanensis and P. x. euramericana ‘Robusta’ proved better than other species (Seth, 1969). These exotic poplars do not regenerate readily due to the absence of seeds caused by the lopping. Dode’s classification of poplar is interesting, he was the first to recognize sub-genera (as well as sections) in the genus. He raised section Turanga of Bunge (including only P. euphractica and P. pruinosa) to subgenus. Wesmael (1868) previously classified these species with the aspens in section Leuce. Browicz (1966) used subgenus Balmiflua (Griff.) Browicz, for the turanga poplars as a whole, and recognized a Kenyan species, viz., Populus ilicifolia in a section Tsava (Jarn.) Browicz (Table 1). Table 1. Classification of Populus Section (synonym) Abaso Eckenwalder Turanga Bunge Leucoides Spach Aigeiros Duby Tacamahaca Spach Populus (Leuce Duby) 2 P. angustifolia James P. balsamifera L. P.ciliata Royle P. laurifolia ledebour P. simonii Carriere P. suaveolens Fischer sla P. szechuanica Schneider P. trichocarpa Torrey and Gray P. yunnanensis Dode P. adenopoda Maximowicz P. alba L. P. gamblei Haines? P. grandidentata Michaux P. guzmanantlensis Vazques and Cuevas P. monticola Brandegee P. sieboldii Miquel P. simaroa Rzedowski P. tremula L. P. tremuloides Michaux Distribution Mexico NE Africa, Asia E Africa Asia China ? USA China N America USA Eurasia, N America N America N America Himalaya Eurasia E Asia NE China, Japan E Eurasia N America Eurasia China Europe, N Africa, Central Asia E Eurasia? N America Mexico Mexico Japan Mexico Europe, N Africa, NE Asia N America Source: Eckenwalder (1996). Key to the Sub Genus 1. Classification Louis-Albert Dode (1875-1945), a noted French dendrologist worked on Poplus and Salix. He had a private plantation having approximately 1,500 poplars and willows. In addition to studying his own living collections he made extentive use of his own herbarium collections. Species Populus Mexicana Wesmael P.euhratica Oliver P. ilicifolia (Engler) Rouleau P. pruinosa Schrenk P. jacquemontiana var. glauca Haines sla P. heterophylla L. P.lasiocarpa Olivier P. deltoides Marshall sla P. fremontii S. Watson P. nigra L. + Leaves entire, coriaceous, glaucous, never tomentose below, both surfaces identical; foliar glands not far projecting; buds small, bowl-shaped, often showing only scale; perianth caducous; stigma 3, large carmine; stamens ± 12; capsule elongated---------------------------------------------------------------Subgenus Turanga Leaves sometimes lobed, light green above, sometimes tomentose below; foliar glands projecting, bowl-shaped; bud average, with several obvious scales; perianth persistent; stigma, 2 pale- ENVIS pink to carmine; stamens 5-20; capsule elongated-----------------------------------------------------------Subgenus Leuce + 2. Catkins always rather compact Leaves green above, lighter of sometimes pubescent below, teeth very deep, never lobed; petiole ± compressed or with quadrangular or rectangular section; buds rather large, viscid with many very obvious scales; perianth persistent; stigma 2-4, greenish, warted; stamens 8-8; capsule ellipticglobular----------------------------------------Subgenus Eupopulus + 3. + 4. + Leaves not lobed; buds sticky--------------------------------3 Leaves glabrous, polymorphous, entire in young plants and suckers ------------------------------------P. euphractica Leaves white tomentose beneath-------P. alba (P. caspica) Leaves with clearly defined translucent border-----------4 Leaves without translucent border------------------------------------------------------------------P. laurifolia (P. pamirica) Leaves rhomboidal, cuneate at base; glands at the base of the blade absent -------------------------------------P. nigra Leaves deltoid at base; glands present at the base of blade----------------------------------------------------P. deltoides Key to the Group 1 + Pubescence less developed on young wood than on old; perianth with divisions scarcely exceeding half the height ------------------------------------------------Euphratica Pubescence more developed in young wood than an old; perianth with divisions almost reaching it base more reduit-----------------------------------------------------Pruinosa Key to the Sections under Subgenus Leuce 1 Mature turion leaves less woolly below; ± lobed; floral bracts little or somewhat divided; multiplication by cuttings possible---------------------------------------albidae + Turion leaves glabrescent, silky-hairy or with rough hairs, ± irregularly serrate-toothed floral bracts deeply divided; ordinary methods of vegetative propagation by cuttings are unsuccessful--------------------------------------Trepidae Indigenous Species There are four indigenous species of Populus namely P. ciliata, P. gamblei, P. jacquemontii var. glauca and P. rotundifolia found in the Himalaya. These species are important for cultivation in Himalayan zone and deserve attention for improvement. These need recognition, systematic survey, collection and evaluation of desirable geographical races and development of suitable clones. Key of Indigenous Species 1. + 2. Key to the Group under Subgenus Eupopulus 1 + Leaves ± glaucous below; foliar glands ridge-shaped; Petioles ± compressed laterally, those of the turion leaves ceably so and all proportions remaining equal to extent of those of brachyplast leaves;----------------------aigiri Leaves glaucous, whitish or white below; foliar glands rather bowl-shaped; petiole quadrangular in cross section; usually laterally compressed, those of the turion leaves constant in shape, usually shorter than those of the brachyblast leaves------------------------Tacamahacae Group under Subgenus Leucoideae Leaves white woodly below when young, thus only glacous; foliar gland rather bowl-shaped; petiole round-sub quadrangular in cross-section; and all the portions remaining equal in extent to those of the brachyblast leaves------------------------------------------------------Leucoideae Key to Common Introduced Species 1. Leaves lobed (or sometimes narrowly oblong), entire on young plants and suckers; buds not sticky---------------2 + 3. + Leaves ovate, acuminate---------------------------------------2 Leaves broadly ovate or orbicular, shortly acute or apiculate------------------------------------------P. rotundifolia Plants dioecious; leaf margin crenate or dentate-serrate;------------------------------------------------------------------------3 Flowers bisexual; leaf margin sharply serrate----------------------------------------------------P. jacquemontii var. glauca Leaves truncate at base; capsule 2-valved----------------------------------------------------------------------------P. gamblei Leaves cordate at base; capsule 3-valved---------P. ciliata Populus ciliata Wall. ex Royle Vern.: Himalayan poplar, safeda, piplas, pahari pipal, chelaun, chalni, banpipal, bagnu, syan, pak butra This is the most widespread species of native poplars. Distributed from Kashmir to Arunachal Pradesh at an altitude between 1,000-3,000m. It is most widely distributed species in India and grows well on alluvial deposits along the water channels, road cuttings, land slides, occasionally forming small gregarious patches on banks of the large water courses. During a qualitative survey during 1995 to 1997 in Uttarakhand in western Himalayas, it was found growing in ban-oak (Quercus leucotrichophora), pangar (Aesculus indica), toon (Toona serrata), deodar (Cedrus deodara), kail (Pinus wallichiana), fir (Abies pindrow), spruce (Picea smithiana), Rhus chinensis, Rhus punjabensis, Rhododendron arboreum, Cornus macrophylla, Coriaria nepalensis, Lyonia ovalifolia, Machilus odoratissima, M. duthiei and hill bamboo Sinarundinara falcata. Ground flora consists of Desmodium elegans, Oplismenus compositus, Arisaema tortuosum, Impatiens scrabida, Daphnae papyracea, Rumex hastatus, Prinsepia utilis, Indigofera heterantha, Rosa moschata, Lonicera quinquelocularis, etc. In eastern Himalaya, it is sparsely distributed in Sikkim, Bhutan and Arunachal Pradesh often grown with Pinus bhutanica, Pinus wallichiana, Salix bhutanica, Salix wallichiana, Alnus nepalensis, Ilex griffithii, Castanopsis hystrix, Trevesia palmata and hill bamboo Sinarundinaria hookeriana. Outside India, it is known from north Myanmar and Yunnan Province of China. It has been observed that Populus ciliata grown near Bomdi La, West Kameng District and Tawang District in Arunachal Pradesh has different shape and size of leaf as compared to western Himalaya. This species affected by rust diseases in winter but without any significant damage. However, in many places, it is affected by parasite Loranthes which causes damage. Keeping in view their fast growing nature various exotic species of poplar have been planted in many parts of northern India. However, not much emphasis has been provided to indigenous species. Thus to encourage the indigenous species of poplar a project entitled ‘Conservation of Indigenous Poplar in India’ was undertaken in Garhwal and Kumaun hills for selection of provenance and plus trees was taken up. In Uttarakhand about 500 trees were observed and marked with numbers for the selection. In the survey best trees were located at Govind Pashu Vihar in Taluka Range (Tons Forest Division) and in Gangotri Range, Uttarkashi Forest Division, where a tree of maximum 4.5 m girth (Fig. 1) was observed. Earlier probably record girth was measured 4.62 m from Kullu Forest Division, Himachal Pradesh (Singh, 1982) and 3.5-4 m from Hazara (Troup, 1921). Joshi (1981) stated that in Uttar Pradesh, the total area of P. ciliata (in mixture with other coniferous and broad leaved species) would be around 40,000 ha, but this species generally constitutes a small component (less than 5 per cent) of the whole crop. Its pure patches are also located at Hanuman Chatti, Badrinath Forest Division below Bhayundar, on way to the Valley of Flowers and Dharali area of Uttarkashi. These pure patches for conservation point of view should be declared as ‘National Poplar Reserve’. According to Rajawat et al. (1987) suitability of P. ciliata had been studied for making various grades of plywood and blockboards like P. deltoides tested earlier. 4 P. ciliata has also been found to give good veneers on peeling. Plywood prepared from the veneers using U-F and P.F. glues has been found to be suitable for making general purpose plywood, marine plywood for concrete shuttering work, preservative treated plywood and fire retardant plywood. The species could thus be included in the relevant Indian Standards specifications for their manufacture. It is also suitable for hardboards (Shukla et al., 1985). It is suitable for making packing cases and crates (Shukla, 1981), It also supports doors. Its wood is of excellent quality for the manufacture of matches (FAO, 1979). It is also used in manufacture of artificial limbs. These includes knee skin assemblies and knee mechanism of all types, hip disarticulation joint, wooden foot and wooden block. The laminated wooden blocks manufactured cover block thigh, block foot, block knee, block ankle, etc. (Misra, 1981). In Kashmir, it is used for building purposes and also as fuel. The bark is used as tonic, stimulant and blood purifier. The leaves are used as a fodder for goats (Khan and Kachroo, 1981). Guha and Mathur (1959) staed that P. ciliata is suitable for writing and printing paper. It is useful for afforesting unstable hill slopes. Haines (1906) and Parker (1918) mentioned that the male trees are rare in P. ciliata. However, Khurana and Khosla (1978) analysed natural stands of P. ciliata and also plantations for sex ratio around Manali, Harlu, lower Kulu and Parvati ranges in Himachal Pradesh. Based on survey of 3,531 trees, it was observed that male trees dominate and have 67.71 per cent frequently as compared to 38.9 per cent female. This gives an approximately 3:2 male to female ratio. Singh (1982) stated that pooling the data of 586 trees examined in various localities of Himachal Pradesh gave the ratio of male and female trees as 2:1. However, during survey in 1995-1998 in Garhwal Himalaya, Uttarakhand, it was found that the population of female trees was maximum (Fig. 2) and that male trees were very less. Joshi (1981) also stated that in the Uttar Pradesh region most of trees were female, male trees were scarce. Gupta (1969) while mentioning its occurrence in Jaunsar and Tehri Garhwal, Uttarakhand also stated that the male trees were very scarce. This indicates that the ratio of male and female trees varies with the locality. P. ciliata can easily be propagated by cuttings. Troup (1921) stated that its regeneration through seeds is negligible. However, the commonest form of its natural reproduction is by root-suckers. The seeds of P. ciliata are light, about 14,000 to 15,000 seeds weigh one gram (Singh, 1981; Beniwal and Singh, 1989). In laboratory condition, 75-95 per cent germination of seed was noted by Singh and Gupta (1981). Mathur et al. (1982) mentioned that under laboratory condition its germination is ENVIS 86.25 per cent, while on land slip under natural condition, only 0.30 per cent was noticed. Under natural conditions, however, seed germination is considerably poor. Some seedlings, manage to grow in crevices of rocks or newly exposed ground such as landslips and road cuttings and on alluvial boulder deposits along streams. The seedlings establishment is uncommon because of the following reasons (Singh, 1982): • Most of the seeds are caught on the grass, weed and moss covering the soil fail to come in contact with mineral soil. • Unfavourable moisture conditions at the time of seed dispersal. Sufficiently moist soil is needed at the time of germination and for a fairly long time after germination. • Susceptibility of seedlings to fungal attacks particularly damping off. • Washing away of seeds and tiny seedlings by run-off water on slopes and their desposition in depressions where they get covered by soil and fail to germinate. Nautiyal et al. (1995) reported its profuse natural regeneration in Tons Forest Division, Uttarakhand. They also stated that the area of around 40 m radius was full of the seedlings. The site was sunny and slopey. A study of the performance of forest clones of poplars and the farm forestry condition trial was laid down at Khaltoo (Himachal Pradesh) in 1976 with six species namely P. ciliata, P. casale; P. yunnanensis, P. trichocarpa, P. oxford and P.deltoides planted at 60 x 30 cm spacing. It was found that maximum survival was recorded in P. ciliata followed by P. deltoides while height and diameter was maximum in P. yunnanensis followed by P. ciliata (Khurana and Khosla, 1978). During the period of 1986 to 1990, seeds were produced in Gaja Nursery, Uttarakhand. The best clones were tried in the field in January 2008. Populus gamblei Dode Vern.: Pipalpate, pilpile It is the southern-most poplar in the Northern Hemisphere and is distributed in Yazuli and Yachuli area of Lower Subansiri District of Arunachal Pradesh. In Darjeeling hills, West Bengal, it is naturally found in Damson forests, where it is sometimes observed colonizing the slip areas. Also occurs along the roads from Kalimpong to Teesta. In the recent past, it has been naturally found common 4 km before Sechu (Sechii) on Kohima-Dimapur Road, Nagaland. About 40 small to medium sized tree were located in the area. A large tree about 15 m high having a girth of 3.2 m (Fig. 3) is also measured. Beside Sechu some tree of this species are also located Niepfei area near Kohima. In Nagaland, Forestry Bulletin, 12(1), 2012 it is used in shifting cultivated fields for temporary hut construction (Naithani et al., 2005). In a very recent (May 2012) quantitative survey conducted by one of the author in Yazuli, Lower Subansiri District, Arunachal Pradesh, P. gamblei was found associated with common trees which Schima wallichii, Dalbergia sericea, Erythrina indica, Callicarpa arborea, Rhus chinensis, Celtis australis, Engelhardtia spicata, Sterospermum chilinoides. Ground cover was with Artemisia nilagirica, Eupatorium adenophorum, Pteridium revolutum, Oxalis corniculata, Lepidagathis incurva, Sida rhombifolia, Bidens pilosa, etc. During March-April each year, natural regeneration of P. gamblei is found in profusion under the areas affected by land slips, the young seedlings appear to colonize the slip affected areas. P. gamblei provides an annual output from 16.3 m per ha to 35.9 m per ha depending on age (Lahri, 1979). The wood of P. gamblei has been found to the suitable for ply, match and packing case industries. Eighteen trees of P. gamblei planted in the year 1975 are growing in the Tashiding I compartment beat in Kalimpong Division, North Bengal. The seeds of P. gamblei are very minute, weighing about 1,500 an ounce and attached to fluffy floss, often difficult to collect because of short time gap between flowering, fruiting and quick dispersal (Ghose, 1969; Lahri, 1979) Muhle-Larsen (1970) reported 12 species of Populus showing change in sex in standing population. Sharma et al. (1999) reported reversion of sex in P. gamblei from male to female in a 20-yr old tree cuttings which were brought from Arunachal Pradesh and planted in the Plant Physiology Discipline of Forest Research Institute, Dehradun. The reversion of sex mentioned by Sharma et al. (1999) is incorrect. This tree, when first flowered was examined and noted that it was female and not male (Fig. 4). Branch cuttings of most of the poplar species root easily without any pretreatment of synthetic growth regulators but cuttings of P. gamblei do not root easily (Guhathakurta, 1973). Ghose and Bhatnagar (1977) stated that rooting response of branch cuttings of P. gamblei to different growth regulator treatments and seasonal variation in rooting. Growth regulators have considerably increased rooting. Twenty-four hours dip treatment in aqueous solution of 200 ppm concentration of indole acetic acid has given best results in which 70 per cent rooting has been achieved. In view of its good rate of growth it offers potential of developing hybrid clones (Guhathkurta, 1973). Populus jacquemontiana Dode var. glauca (Haines) Kimura (P. glauca Haines) Vern.: Pipalpate or dude malata This is the only Indian poplar which has bisexual flowers (Fig. 5). It is distributed in Tonglo in Sikkim and Eastern Nepal 5 Fig. 1. Populus ciliata in Uttarkashi Forest Division, Uttarakhand tree with a girth of 4.5 m. Fig. 2. Populus ciliata female. Fig. 3. Populus gamblei tree, 15 m high with a girth of 3.2 m in Nagaland. Fig. 4. Populus gamblei female inflorescence. Fig. 5. Populus jacquemontiana var glauca inflorescence. (Courtesy: Stainton, 2005). 6 ENVIS at an altitude between 2,500-2,900 m. It is generally found in forests clearing; quite common around villages. A beautiful colour photograph of this rare species was given by Stainton (2005). It is also regarded by some experts as a form of P. ciliata (FAO, 1979). At present, it is not correct because P. ciliata is dioecious. Populus jacquemontiana var. glauca was tested against the cadmium stress which is highly toxic heavy metal, which causes strong oxidative stress, thereby, interaction PSII and the photosynthetic electron transport by Solti et al. (2011) and found that an acute acclimatization phase were identified as a consequence of the delay in activation of anti-oxidative defense mechanism, the protective role of which is important in the acclimatization to moderate cadmium stress. Populus rotundifolia Griff.(P. microcarpa Hk.f. and Th.; P. bonatii Leve.) Vern.: Kashing, kashi A shrub or tree, 2-10 m. This species is endemic to Thimpu, Punakha and Bumthang District of Bhutan Himalaya, distributed in Pinus wallichiana (blue pine) forest at an altitude between 2,300-3,050 m (Grierson and Long, 1983). This little known species has been included here because phyto-geographically Bhutan is a part of eastern Himalaya. Therefore, in future it can be found in adjacent states like Sikkim and Arunachal Pradesh as the vegetation of these states is similar to Bhutan. In the plains, introduced clones of P. deltoides have given good performance. However, instead of depending solely upon introduced clones of P. deltoides for the hills, work should be initiated in indigenous species to generate new clones or hybrids. Suggested lines of work are: • Patches of wild poplar should be declared and maintained as ‘National Poplar Reserves’. • Germplasm banks of plus trees of indigenous poplars should be raised at plantation sites in hills to study genotype and site interaction. • A poplar breeding programme incorporating indigenous and exotic poplars should be taken up on priorities to generate superior clonal material for planting under agroforestry in hill areas and plains. References APG (Angiosperm Phylogeny Group). 2003. A update of the angiosperm phylogeny group classification for the orders and families of flowering plants: APG II. Forestry Bulletin, 12(1), 2012 Botanical Journal of the Linnean Society, 141: 399436. Beniwal, B.S. and Singh, N.B. 1989. Observation on flowering, fruiting and germination behaviour or some useful forest plants of Arunachal Pradesh. Indian Forester, 115 (4): 216. Bor, N.L. 1958. Manual of Indian forest botany. London, Oxford University Press. pp. 111-112. Browicz, K. 1966. Populus ilicifolia (Engler) Rouleau and its taxonomic position. Acta Societatis Botanicorum Poloniae, 35(2): 325-335. Chase, M.W.; Zmarzty, S.; Lledo, M.D.; Wurdack, K.J.; Swensen, S.M. and Fay, M.F. 2002. When in doubt put in Flacourtiaceae: A molecular phylogenic analysis based on plastid rbcL DNA sequences. Kew Buletin, 57:141-181. Eckenwalder, J.E. 1996. Systematics and evolution of Populus. In: Stettler, R.F; Bradshaw, H.D.; Heilman, P.E. and Hinckley, T.M. Eds. Biology of Populus and its implications for management and conservation. Ottawa, NRC Research Press. pp. 7-32. FAO (Food and Agriculture Organisation). 1979. Poplars and willows in wood production and land use. Rome, FAO. 328p. Ghose, R.C. 1969. A short note on Populus gamblei. [Unpublished]. Ghose, R.C. and Bhatnagar, H.P. 1977. Rooting response of branch cutting of Populus gamblei Dode. Indian Forester, 103(6): 382-386. Grierson, A.J.C. and Long, D.G. 1983. Flora of Bhutan. Vol 1. Part 1. Edinburgh, Royal Botanic Garden. 186p. Guha, S.R.D. and Mathur, G.M. 1959. Chemical pulp for writing and printing papers from Populus ciliata Wall. (Poplar). Indian Pulp and Paper, 14(5): 1-3. Guhathakurta, P. 1973. Populus gamblei Dode- a little known poplar of eastern Himalaya. In: Forestery Conference, 1st, Dehradun, 6-10 December 1973. Proceedings. Delhi, Controller of Publications. Gupta, B.L. 1969. Forest flora of the Chakrata, Dehradun and Saharanpur Forest Division, Uttar Pradesh. Dehradun, FRI. Joshi, R.C. 1981. Distribution and management of Populus ciliata Wall. in Uttar Pradesh. In: Symposium on Silviculture, Management and Utilization of Poplars, Srinagar, 15-18 October 1979. Proceedings. Simla, Government of India Press. pp. 95-97. Haines, H.H. 1906. On two new species of Populus from Darjeeling. Journal of the Linnean Society of London, Botany, 37(2): 407-409. 7 Khan, A. and Kachroo, P. 1981. Utilization of poplars. In: Symposium on Silviculture, Management and Utilization of Poplars, Srinagar, 15-18 October 1979. Proceedings. Simla, Government of India Press. pp. 157-159. Khurana, D.K. and Khosla, P.K. 1978. Review of work on poplars in Himachal Pradesh with reference to Himalayan poplars. WIMCO Financed Project Reoprt. Solan, Department Forestry, H.P. University. 34p. Lahri, A.K. 1979. Vegetative propagation of forest trees. Indian Forester, 105(2): 101-105. Mathur, H.N.; Singh, P.P. and Sharma, K.C. 1982. Populus ciliata - A promising tree species for soil conservation in hilly areas. Indian Forester, 108(9): 599-604. Misra, Y.P. 1981. Utilization of Populus ciliata for artificial limbs manufacture. In: Symposium on Silviculture, Management and Utilization of Poplars, Srinagar, 15-18 October 1979. Proceedings. Simla, Government of India Press. pp. 160-162. Muhle-Lalrsen, C. 1970. Recent advances in poplar breeding. International Review of Forestry Research, 3: 1-67. Naithani, H.B.; Deorani, S.C. and Amenba Yaden, T. 2005. Populus gamblei Dode - A tree new to Nagaland, India. Indian Forester, 131(9): 1212-1216. Naithani, H.B.; Sumer Chandra and Mohinder Pal. 2001. Poplars with special reference to indigenous species. Indian Forester, 127(2): 230-237. Nautiyal, S.; Uniyal, D.P. and Chaukiyal, S.P. 1995. Natural regeneration of Populus ciliata. Indian Forester, 121(7): 673. Parker, R.N. 1918. A forest flora for the Punjab, Hazara and Delhi. Delhi, Superintendent, Government Printing Press. 510p. Rajawat, M.S.; Shukla, K.S. and Sharma, R.C. 1987. Studies on the suitability of Populus ciliata (poplar) for plywood. In: Seminar organized by Punjab State Forest Development Corporation, Chandigarh, 17th February 1987. Papers. [unpublished]. Seth, S.K. 1969. Poplar trials in Uttar Pradesh. U.P. Forest Bulletin No. 34. Lucknow, U.P. Forest Department. 106p. 8 Sharma, V.K.; Sharma, S.K. and Rawat, M.S. 1999. Sex reversal in Populus gamblei Dode. following grafting. Indian Forester 125(5): 533-535. Shukla, K.S.; Shah, R.S. and Bagga, J.K. 1985. Suitability of Populus ciliata (poplar) for hardboard. Indian Forester, 111(4): 225-229. Shukla, N.K. 1981. Poplar wood for packing cases. In: Symposium on Silviculture, Management and Utilization of Poplars, Srinagar, 15-18 October 1979. Proceedings. Simla, Government of India Press. pp. 154-156. Singh, N.B. and Kumar, D.. 1998. Genetic improvement of poplar in India. In: Workshop-cum-Peer Review on Poplar, 2nd, Dehradun, 8th December 1998. Papers. Dehradun, FRI. Singh, R.V. 1979. Silvics and ecology of Populus ciliata. In: Symposium on Silviculture, Management and Utilization of Poplars, Srinagar, 15-18 October 1979. Proceedings. Simla, Government of India Press pp. 62-66. Singh, R.V. 1982. Research work on poplar at Conifer Research Centre, Shimla. In: Workshop on Poplars, Haldwani, 23-24 January 1982. Proceedings. Singh, R.V. and Gupta, K.C. 1981. Preliminary studies on germination of Populus ciliata. In: Symposium on Silviculture, Management and Utilization of Poplars, Srinagar, 15-18 October 1979. Proceedings. Simla, Government of India Press. Solti, A.; Szollosi, Erzsebet; Gemes Juhasz, Aniko; Meszaros, Ilona; Fodor, Ferenc and Sarvari, Eva 2011. Significance of antioxidative defence under longterm Cd stress. Acta Biological Szegediensis, 55(1): 151-153. Stainton, A. 2005. Flowers of the Himalaya: A supplement. New Delhi, Oxford University Press. Tewari, D.N. 1993. Poplar. Dehradun, Surya Publications. 321p. Troup, R.S. 1921. The silviculture of Indian trees. Vol. 3. Oxford, Clarendon Press. pp. 957-965. Wesmael, A. 1868. Salicineae (Populus). In: de Candolle, Alphonse. Prodromus systematic naturalis regni vegetabilis. Vol. 16, Part 2. pp. 323-331. z ENVIS Status of Poplar Introduction in India Dinesh Kumar and N.B. Singh1 Silviculture Division, Forest Research Institute, Dehradun - 248 006 College of Forestry, Dr. Y.S. Parmar University of Horticulture and Forestry, Solan - 173 230 1 Introduction P Systematic introduction of exotic poplars took place more than seven decades ago, and that more than 600 clones and 266 open-pollinated seed families have been introduced into India from different parts of the world oplars hold a place of great significance in India as they are among the most preferred tree species in the unique agroforestry systems in northern part of the country. Six indigenous species of poplars, viz., Populus ciliata, P. alba, P. euphratica, P. gamblii, P. jacquemontii var. glauca and P. rotundifolia are reported in India. Some experts consider P. alba and P. euphratica as exotics (Naithani et al., 2001). However, since both these species grow widely in several areas and record of their introduction are not available, these two species are being treated as indigenous in this paper. Poplars, primarily the exotic species, are being grown on around 312,000 hectare area in various agroforestry models in Punjab, Haryana, Uttar Pradesh, lower hills and outer valleys of Himachal Pradesh, Uttarakhand and Jammu and Kashmir. Exotic poplars are also planted as avenue plantations in Kashmir on a significant scale. Now, with the efforts of Indian Council of Forestry Research and Education (ICFRE), cultivation of poplar in agroforestry has been extended to Vaishali District of Bihar. Populus deltoides is the most popular exotic species. The annual returns from its cultivation are estimated to be up to 250,000 rupees per hectare per year. Wood from poplars is the backbone of vibrant plywood, board, match and paper industrial units. Poplars provide huge cash returns to individuals and communities engaged in their cultivation and management, contribute considerably to government exchequer, reduce pressure on forests and entail massive ecological and environmental benefits besides providing a wide range of other wood products and employment opportunities to various subsidiary sectors. While indigenous poplars have mostly remained confined to forest areas and community lands, exotic poplars, in addition to native species and eucalypts, have been responsible for creating wooded landscape in areas outside the forest in north India. Systematic introduction of exotic poplars took place more than seven decades ago. This paper gives an account of the introduction of exotic species of poplars in the country. Species Introduced The following species of Populus have been introduced into India so far: • P. deltoides • P. nigra • P. laurifolia • P. yunnanensis • P. trichocarpa • P. violascens • P. maximowiczii • P. simonii • P. szechuanica • P. tacamahaca • P. tremuloides • P. grandidentata • P. robusta In addition to the above species, interspecific hybrids of several species of poplars have also been introduced. The most important among them has been P. x euramericana, a hybrid between P. deltoides and P. nigra (Kaul and Sharma, 1982). More than 600 clones and 266 openpollinated seed families have been introduced into India from different parts of the world. Reliable data on suitability of different species were not available till late 1960s. Hence, till that time focus was on introducing germplasm of all possible species. However, in view of better adaptation and productivity of P. deltoides in areas of commercial poplar cultivation in India, later introductions have mostly focused on P. deltoides only. Thus, P. deltoides has so far been the most important exotic species of this genus in the country. So widespread has been its cultivation in North India that the term ‘poplar’ has become synonymous with P. deltoides in the country. Forest Research Institute, Dehradun (FRI) has been the major organization which introduced clonal material from abroad. State forest department of Uttarakhand (Haldwani centre) and WIMCO Ltd. have also introduced clones from abroad. There has been good exchange of introduced material among these organizations. Introduced material has also been supplied by them to other government as well as non-government agencies involved in poplar cultivation in India. Germplasm in the form of seed has been introduced by FRI and Dr. Y. S. Parmar University of Horticulture and Forestry, Solan, Himachal Pradesh, Uttar Pradesh Forest Department (now Uttrakhand) and WIMCO Ltd. 10 Timeline of Introduction of Exotic Germplasm Early Phase The fastigiate form of P. nigra; i.e., Lombardy poplar or pyramidal poplar (cv. ‘Italica’ and cv. ‘Pyramidalis’) is frequently planted in western Himalayas up to 3,700 m altitude, particularly in Kashmir. Besides P. nigra, some clones of P. deltoides and P. alba are planted here and there in Kashmir. How and when these clones were introduced is not known (Khan et al., 1961). Middle Phase This phase has been the most important phase of poplar introduction in India and has played a pivotal role in laying the foundation of commercial cultivation of poplar. The first systematic attempt at introduction of European and Euramerican poplar clones was made by the forest department of Uttar Pradesh (now Uttarakhand) by 1950 when hybrid clones of P. x euramericana cv. ‘Serotina’, P. x euramericana cv. ‘Gelrica’, P. x euramericana cv. ‘Robusta’ and P. x berolinensis were tested in the Himalayas at 1,500 to 2,400 m elevation and 1,000 to 1,500 mm rainfall. Trials on a larger scale were started by FRI by 1959 when 24 clones of various hybrids were imported through the British Forestry Commission. These clones were planted in Kashmir, Himachal Pradesh, Punjab, Uttar Pradesh (including presentday Uttarakhand), West Bengal and Tamilnadu (Ootacamund) at 1,200 to 1,800 m altitude, besides being planted in demonstration area of FRI. This collection included 17 clones of black poplar (Section Aigeiros), 5 of balsam poplar (Section Tacamahaca) and 2 of Section Leucoides (Khan et al., 1961). During 1959 to 1976, FRI introduced 199 clones of various exotic species and hybrids, which included 29 clones of P. deltoides, among others. Clones G-3, G-48 and D-121 which subsequently became very popular with the growers clones, were also introduced during 1969 (Kaul and Sharma, 1982). WIMCO also introduced exotic clones of poplars directly from abroad. Another set of 138 clones of Populus was received by FRI, Dehradun from 1977 to 1981. This contained 98 clones of P. deltoides (Kaul and Sharma, 1982). Introduction of more clones continued and, as a result, about 440 clones of Populus spp. had been introduced till 1983 by FRI (Tewari, 1993). Multiplication of clones by vegetative propagation and their distribution to different states also continued. However, systematic feedback on performance of clones in those states was not received. More clones of P. deltoides were sent to India during mid-1980s by Dr. Sam Foster in Louisiana (U.S.A.) who made ENVIS controlled crosses among select clones of Stoneville (Mississippi, U.S.A) origin. These clones were tested by WIMCO and discarded as not suitable. Another collection of clones from throughout the USA was sent to the Haldwani centre of state forest department by Dr. E.A. Hansen of the United States Forest Service during 1986 (Land, 1996). From of this collection, nursery trials were conducted on 121 clones of P. deltoides, 27 clones of P. trichocarpa and 20 clones of P. deltoides x P. trichocarpa at Lalkua (Haldwani). Field trials in the Tarai region of Uttar Pradesh (including present-day Uttarakhand) on new introductions revealed superior growth of clones G-3, G-48, D-67, D-75, D-82, D-121, D-161, D-171, D-181 of P. deltoides in comparison with clones of other species (Chaturvedi, 1982). In view of this, several trials on different clones of P. deltoides were carried out in the alluvial plains of north India during 1980s and 1990s. Clones G-3, G-48 and D-121, which had shown good performance in preliminary tests, were included in most of the trials. Dinesh Kumar et al. (1999) observed that only 3 to 5 (sometimes around 10) clones of P. deltoides were usually tried in the experiments. Clones G-3, G-48 and D-121grew very well in several trials. Apart from these three clones, the other clones were not consistently included in the experiments in other regions conducted by various researchers (Dhanda, 1982; Singh et al., 1987; Sharma, 1991; Gera et al., 1993; GBPUAT, 1994). Dinesh Kumar et al. (1999) analysed the performance of 108 clones of poplars, introduced in India since late 1950s, in two field trials in Haldwani and ranked them on the basis of stem wood volume (Table 1). From the study, it emerged that clones S7C8, 82-35-4 and 113324 of P. deltoides give higher yield than G-48, although G-48 has remained one of the most popular clones over the last two decades in agroforestry plantations. Late Phase Unlike clonal stock that was imported during the previous two phases, open-pollinated seed has been introduced from abroad in this phase. All the seed has so far belonged to P. deltoides only and the USA has been the donor country. A collection of 59 lots of open-pollinated seed of P. deltoides trees growing in the USA was introduced in Haldwani (Jha and Chhimwal, 1992). From this material only 6 clones were planted in the field. Growth data up to 3 years of age are reported (Jha and Gupta, 1992). In 1990, Dr. Y.S. Parmar University of Horticulture and Forestry, Solan obtained open-pollinated seeds from 103 trees of P. deltoides along the Colorado and Brazos rivers in Texas and along the southern part of Mississippi river form Forestry Bulletin, 12(1), 2012 Baton Rouge (Louisiana) to Davenport (Tennessee) (Land, 1996). Following three years of nursery measurements, 50 clones were developed out of this collection. It was later realized that most of the germplasm of P. deltoides had been brought from cooler region of natural range of this species in North America. In comparison with the northern range (above 38oN latitude), the climatic conditions in the southern range (below 38oN latitude) of natural distribution match more closely with the conditions prevailing in the P. deltoides-growing region of India. Dinesh Kumar et al. (1999) examined the origin of 108 clones of P. deltoides and found that only 25 per cent part of the Table 1. Ranks of 108 exotic clones of poplar Rank Clone Rank Clone Rank Clone 1 S7C8 37 2503 73 ST-148 2 82-35-4 38 74/27 74 4 3 113324 39 ST-66 (D-66) 75 ECO-28 4 G-48 40 S-748/111 76 82-18-2 5 3167 41 D-61(ST-61) 77 A-24 6 3324 42 22-4 78 3234 7 111828 43 82-26-5 79 LUISA-AVANZO 8 73/53-2 44 63/51 80 R-89 9 A-13 45 4/64 81 TRIPLO 10 D-74 (ST-75) 46 421-2 82 721502 11 D-75 (ST-75) 47 3678 83 2498 12 S4C21 48 A-343 84 2/56 13 82-33-3 49 19/66 85 BL-COSTA 14 ST-72 50 ST-244 86 3201 15 110702 51 S13C14 87 9/54-9 16 S7C15 52 LUX (69/55) 88 3456 17 S7C20 53 82-14-1 89 110504 18 28/8 54 G-3 90 1358 19 82-42-5 55 2500 91 111232 20 S7C4 56 S13C11 92 17-10 21 ONDA (72/51) 57 A-194 93 4/68 22 D-121 (ST-121) 58 1147 94 11-3 23 D-171 (ST-171) 59 3677 95 73/53-7 24 ST-124 60 61/58 96 64-243-1 25 D-82 (ST-82) 61 I-18/62 97 3298 26 72/58 62 54-2 98 D-19 27 S7C7 63 3287 99 2651 28 D-67 (ST-67) 64 82-29-2 100 1/56 29 S7C1 65 110120 101 1467 30 S7C2 66 D-29 (ST-29) 102 2 31 2502 67 110610 103 2652 32 ST-70 68 82-41-4 104 3650 33 82-36-1 69 D-181 (ST-181) 105 3232 34 S7C3 70 3651 106 JACOMETTI 35 3576 71 ST-92 107 2650 108 3203 36 28/13 72 2656 Source: Dinesh Kumar et al., 1999. 11 southern native range of the species was represented in the germplasm in India (Fig. 1). Clones originating from areas located to the east of the Mississippi river in the southern range of the species have not been tested in India. subjected to trials at four sites in Uttarakhand and western Uttar Pradesh. These trials by FRI led to the identification of the most productive clones in the test sites. Significant genotypeenvironment interaction was observed. However, the best five clones of any site were present among the best 16 clones of all other sites. Overall, clone FRI-AM-59, FRI-AM-58, FRIAM-44, FRI-AM-41 and FRI-AM-54 were among the best seven performers (Table 2). Incidence of any significant clonespecific disease or insect attack was not recorded on any of these clones. Clone G48 and S7C8, the two check clones, ranked from 12 to 26 (rank one being assigned to the best clone) and from 5 to 17, respectively. The study indicates potential for multiplication and deployment (Dinesh Kumar and Singh, 2001) of the best five clones of FRI-AM series in operational plantations. Introduction of Poplar Outside Traditional Cultivation Zone Source: Dinesh Kumar et al., 1999. Fig. 1. Four populations in natural range of P. deltoides, USA from where most of germplasm of this species has been introduced. The FRI introduced more germplasm from abroad focusing on southern part of the USA. In the year 1997, seeds of 104 open-pollinated families of this species belonging to 44 stands covering 10 states in the south and east parts of USA were brought to the institute. After testing of seedlings in nursery, cloning of superior individuals (named FRI-AM series clones) and preliminary testing of clones in field, a field test was laid out at Hoshiarpur, Punjab. The best 40 clones identified on the basis of this field test were further Table 2. Best 30 clones of FRI-AM series ranked on the basis of stem volume in Hoshiarpur, Punjab Rank Clone Rank Clone Rank Clone 1 FRI-AM-58 11 FRI-AM-106 21 FRI-AM-109 2 FRI-AM-51 12 FRI-AM-4 22 FRI-AM-7 3 FRI-AM-41 13 FRI-AM-89 23 FRI-AM-13 4 FRI-AM-32 14 FRI-AM-53 24 FRI-AM-45 5 FRI-AM-54 15 FRI-AM-105 25 FRI-AM-30 6 FRI-AM-44 16 FRI-AM-40 26 FRI-AM-93 7 FRI-AM-59 17 FRI-AM-24 27 G-48 (control) 8 FRI-AM-12 18 FRI-AM-33 28 FRI-AM-21 9 FRI-AM-48 19 FRI-AM-87 29 FRI-AM-14 10 FRI-AM-42 20 FRI-AM-20 30 FRI-AM-50 12 Exotic poplar has traditionally been planted above 28oN latitude in India in parts of Punjab, Haryana, Uttar Pradesh, lower hills and outer valleys of Himachal Pradesh, Uttarakhand and Jammu and Kashmir. Singh et al. (1999, 2001a, b and c) strongly advocated the need for extending cultivation of P. deltoides to lower latitudes. Dr. N.B. Singh, Chief Technical Advisor (poplar) during 1999-2001 supplied germplasm of promising clones to researchers in areas both inside and outside the traditional planting zone covering Jammu and Kashmir, Himachal Pradesh, Punjab, Haryana, Uttar Pradesh, Bihar, West Bengal, Orissa, Chhattisgarh, Maharashtra, Gujarat and Assam. Among areas outside the traditional zone, performance of the clones in Bihar was encouraging and poplar cultivation was recommended in these sites. Due to lack of feedback about performance in other non-traditional areas, it can be assumed that performance of poplar was not up to the expectations in those areas. In previous efforts, P. deltoides had been planted in Maharashtra where it showed good performance initially but died after 3-4 yrs (Ballal, 2001). Gera et al. (1993) planted this species in sporadically irrigated site at Jabalpur in Madhya Pradesh and observed good early growth but the plants began to die back at 3 years. The first author of this paper has observed good growth of P. deltoides at six years of age in farmers’ field at Chhindwara in Madhya Pradesh, thereby, suggesting that inadequate irrigation during summer season, which usually results when poplar is not intercropped with appropriate agricultural crop, might be the key factor behind ENVIS failure of this species in introduction trials in some sites. Failure of P. deltoides was also noticed in Kerala state in south India, where this plant was planted in unirrigated land. Encouraged by the initial performance of P. deltoides in Bihar, ICFRE has, in a major initiative, introduced large scale cultivation of this species in northern Bihar. About 6.10 million plants of poplar have been multiplied (Fig. 2) and planted (Fig. 3) in district Vaishali during the first phase of the project that started in 2005. Wherever site selection and cultural operations were done well, performance in the plantations there, has been comparable to plantations in the traditional zone. Introduction of Poplar into Agroforestry P. deltoides has very high growth rate (mean annual increment of 20 to 25 m3/ha/year) in India. The high productivity is achieved only when it is intercropped with such agricultural or horticultural crops as require intensive irrigation and other cultural operations. Research on agroforestry of this species Fig. 2. Pre-treatment of cuttings of P. deltoides for raising farmer’s nursery at Vaishali, Bihar. Fig. 3. Boundary plantation of P. deltoides by a farmer with small landholding at Vaishali, Bihar. Forestry Bulletin, 12(1), 2012 was started by FRI Dehradun, Haldwani centre of state forest department and WIMCO in early 1960s. Cultivation of P. deltoides in agroforestry system by farmers started in 1970s; during early years it was practised only by very rich and progressive farmers who had surplus land and financial power to bear the risk of plantation failure. The credit of taking this tree to the farmers for widespread plantation goes to WIMCO that started an extension project for massive plantation of poplar in Punjab, Haryana and western Uttar Pradesh 1976 onward and with financial support of National Bank for Agriculture and Rural Development (NABARD) between 1984-1995 and independently thereafter. WIMCO-NABARD poplar scheme has been a noble venture of joint partnership between the industry and the banking sector working together for the benefit of the farming community, industry and unemployed people besides providing environmental services. References Ballal, A.N.; Gogate, M.G.; Dakshindas, S.D. and Karunakaran, M. 2001. Introduction of poplar species in Maharashtra State – an assessment. Indian Forester, 127(1): 30-43. Chaturvedi, A.N. 1982. Poplar farming in U.P. (India). U.P. Forest Bulletin No. 45. Lucknow, U.P. Forest Department. Chaturvedi, A.N. and Rawat, B.S. 1994. Poplar tree improvement programme. Indian Forester, 120(1): 1420. Dhanda, R.S. 1982. Trials of poplars in Punjab. Workshop on Poplars, Haldwani. 12-24 January 1982. Proceedings. Dehradun, FRI and Colleges. pp. 56-66. Dinesh Kumar and Singh, N.B. 2001. Age-age correlation far early selection of clones of Populus in India. Silvae Genetica, 50(3-4): 103-108 Dinesh Kumar, Singh, N.B.; Rawat, G.S.; Srivastava, S.K. and Mohan, D. 1999. Improvement of Populus deltoides Bartr. ex Marsh in India - I. Present status. Indian Forester, 125 (3): 245-263. GBPUAT (G.B. Pant University of Agriculture and Technology). 1994. Annual progress report of AllIndia Coordinated Research Project on Agroforestry. Pantnagar, G.B. Pant University of Agriculture and Technology. pp.15-16. Gera, M.; Sharma, S.; Rawat, P.S.; Dinesh Kumar and Bhandari, A.S. 1993. Preliminary studies on nursery and field performance of Populus deltoids Marsh, under Jabalpur conditions. Indian Journal of Tropical Biodiversity, 1 (3-4): 307-312. 13 Jha, K.K. and Chhimwal, C.B. 1992. Nursery testing for development of poplar planting in Tarai. Indian Journal of Forestry, 15 (4): 285-297. Jha, K.K. and Gupta, C.1992. Broadening genetic base of poplar in Tarai. Indian Forester, 188 (1): 2127. Kaul, R.N. and Sharma, K.K. 1982. Status report on poplars. Workshop on Poplars, Haldwani, 23-24 January 1982. Proceedings. Dehradun, FRI and Colleges. pp. 2153. Khan, M.A.W.; Rajkhowa, S. and Ghei, V.N. 1961. Trials with poplars. In: Silvicultural Conference, 10th , 15-20 November and 22-25 November 1961. Proceedings. Dehradun, FRI and Colleges. pp. 691-703. Land, S.B. 1996. Consultant report: Forest regeneration/tree improvement of poplars in India, July 1996. Forestry Research, Education and Extension Project, ICFRE, Winrock International. 46p. Naithani, H.B.; Chandra, S.; Pal, M. 2001. Indian poplars with special reference to indigenous species. Indian Forester, 127(2): 230-237. Sharma, S.K. 1991. Observations on the performance of poplars in the cold desert area of Spiti Valley (H.P.). Indian Forester, 117(4): 248-285. 14 Singh, N.B.; Dinesh Kumar; Rawat, G.S. and Srivastava, S.K.1999. Improvement of Populus deltoides Bartr. ex Marsh in India - II. Future strategy. Indian Forester, 125 (4): 341-354. Singh, N.B.; Dinesh Kumar; Gupta, R.K. and Singh K. 2001a. Poplar improvement: Need implementation and achievement. In: Advances in Horticulture and Forestry, edited by S.P. Singh. Jodhpur, Scientific Publisher (India). pp. 205-237. Singh, N.B.; Dinesh Kumar; Gupta, R.K.; Singh K. and Khan, G.H. 2001b. Role of poplar in sustainable development of India. Indian Journal of Agroforestry, 3(2): 92-99. Singh, N.B.; Dinesh Kumar; Rawat, G.S.; Gupta, R.K.; Singh, K.; Negi, S.S. 2001c. Clonal evaluation on poplar (Populus deltoides Bartr.) in Eastern Uttar Pradesh. II - Estimates of genetic parameters in field testing. Indian Forester, 127(2): 163-172. Singh, N.P.; Om Prakash and Singh, R.P. 1987. Present status of poplars in Tarai belt of Uttar Pradesh. In: Social forestry for rural development, edited by P.K. Khosla and R.K. Kohli. Solan, ISTS and University of Horticulture and Forestry. pp. 161-166. Tewari, D.N. 1993. Poplar. Dehradun, Surya Publications. pp. 63-69. z ENVIS Status of Poplar Culture in India R.C. Dhiman Wimco Seedlings Division, WIMCO Ltd., Rudrapur - 263 153 Introduction P A major share of poplar is grown in parts of Punjab, Haryana, Uttarakhand, Uttar Pradesh and some adjoining states and these locations have been collectively designated as the region of intensive poplar culture (RIPC) Forestry Bulletin, 12(1), 2012 oplar culture in India is mainly taking place on the farmland in parts of the northern India, though a very small percentage is also planted on the forest land by the state forest departments in and around the Himalayan ranges. Introduction trials of poplar species and clones were tried 1950 onwards in the state of Uttar Pradesh and some other states (Chaturvedi, 1982 a and b). The tree is, however, being regularly promoted on farmers’ fields by WIMCO – a safety match company since 1976 (NAEB, 1993; Jain and Singh, 1999; Dhiman, 2008a). A number of private nursery growers and a couple of state forest departments also contribute in supplying a sizeable number of saplings to the growers for making fresh plantations. Increased wood availability from WIMCO’s promoted programme encouraged establishment of other wood based industrial units in and around its growing region. Due to the increased demand of poplar wood, its trade expanded in the unorganized sector and accordingly its culture. Poplar culture and usage are now fully merged into the social, ecological, agricultural, silvicultural, economical and industrial applications, which are immensely helping in the economical transformation of growers and the region. Poplar is generating goods that include timber, firewood, fodder, leaf manure, etc. The use of poplar wood is now diversified to around three dozen products of which panel products, firewood, paper pulp, match splints, sports goods, artificial limbs are the major ones (Dhiman, 2008b). Its farming helps in sequestration of harmful gases into wood biomass and soil, locking greenhouse gases in products made from its wood; substituting sustainably grown firewood for fossil fuels in domestic and industrial use; bioremediation of soil, air and water by absorbing pollutants; conserving soil and water along the ecologically sensitive river basins of Ganga, Yamuna, Satluj, Beas, Sharda and their tributaries; and reducing industrial effluent load in paper industry by using poplar pulpwood that requires less chemicals in processing in comparison with the traditional pulp woods. Poplar culture also improves water use economy by shifting growing of high water demanding paddy crop to low water demanding agriculture crops grown inside poplar plantations. It has improved living conditions of rural people by generating an employment potential of approximately 100 million man days in poplar related activities mostly in rural locations (Dhiman, 2008b) and further sustaining the agricultural production 15 system by shifting from the monotonous paddy-wheat rotation to ecologically more sustainable and integrated multiple cropping land use with sylvan landscape. Poplar culture in India is assessed to yield approximately 7.5 Mt timber, 1 Mt pulp wood, approximately 5 Mt firewood (also includes wood wastage from industry) and sequestration of approximately 2.50 MtC per annum (Dhiman, 2009) based on planting and harvesting of 20 M trees per annum on 10 yrs average basis. The planting number of its saplings is now increased to over 30 million and, therefore, the benefits of goods and services from its culture have also increased (Table 5 and 6). This paper summarizes the present status of poplar culture especially on volume of its nursery production and fresh plantations made during 2011-12. Trends in Poplar Nursery and Plantation Culture Poplars are one of the first tree species which were grown in the hills for getting firewood, fodder and small timber for local consumption. Occurrence of approximately 600-yrs old P. balsamifera tree in Leh town (Fotidar, 1983) and that of other trees of this and other species in Jammu and Kashmir (J. and K.), Himachal Pradesh (H.P.) and Arunachal Pradesh (Naithani and Sumer Chandra, 1999; Chauhan and Lakhanpal, 2000) confirms poplar being grown in hills for centuries. Some poplar trees recorded in and around Budhist temples (Gompas) also indicates their sacred value in India (Dhiman, 2010a). A major share of poplar is grown in parts of Punjab, Haryana, Uttarakhand, Uttar Pradesh and some adjoining states and these locations have been collectively designated as the region of intensive poplar culture (RIPC) (Dhiman, 2012). RIPC stretches from western limits in Punjab to eastern limits inside north western Bihar and from north near foot hills of Himalayas down towards north central Haryana and Uttar Pradesh. Poplar culture in this region is based on indigenously developed and introduced cultivars of P. deltoides. Some other introduced and indigenous species planted on a limited scale in the central and inner Himalayas especially in the cold arid region of Jammu and Kashmir and Himachal Pradesh states are P. nigra, P. alba and P. balsabifera. Many productive clones of P. deltoides have now been introduced in the cold arid region during the last three decades, and this species is now preferred over other poplar species because of its fast growth almost everywhere. P. ciliata and P. gamblei are the poplars indigenous to Himalayas and some of their plantations have been made on forest land for diverse forestry purposes. A major share of poplar is grown as a cash crop similar to many agricultural crops. Spread in its nurseries and plantations depends on market wood prices and the trends, till date, indicate increase in its culture with increase in valuation of its wood. Both the market wood prices and its fresh plantations have been increasing since 2005. Within the RIPC and elsewhere, the intensity of poplar culture is concentrated in certain locations. Poplar culture within each district, location, state and RIPC is not uniformly distributed and there are imbalances in its spread. Poplar growing locations in each state have been categorized into excellent, large, medium, low, and rare/casual levels based on the volume of planted poplar in those locations (Table 1). There are three distinct and concentrated zones of poplar culture within the RIPC around which maximum poplar is grown in the country. The two zones located on the western side of poplar culture lie around the river basins whereas the third lies in the Tarai region of Uttarakhand and Table 1. Intensity of poplar culture in different districts of India S. no. 1. Scale 2. Large Central Kashmir 3. Medium 4. Low 5. Rare North Kashmir, South Kashmir Kathua and Poonch of Jammu region; Ladakh and Kargil of Ladakh region Other districts 16 Jammu and Kashmir Himachal Pradesh Extensive Punjab Haryana Uttarakhand Uttar Pradesh Hoshiarpur, SBS Nagar, Roop Nagar, along the river banks of Beas and Sutlej Yamunanagar Udham Singh Nagar and Haridwar Amritsar, Gurdaspur, Jalandhar, Kapurthala, Ludhiana Karnal, Panchkula, Ambala, Kurukshetra Panipat, Kaithal Saharanpur, Muzaffarnagar, Bijnor, Meerut, Rampur, Bareilly, Pilibhit, Moradabad, Jyotiba Phule Nagar Baghpat, Amroha, Badaun, Shahajahanpur, Kheri Dehardun and Nainital Bulandshahr,, Bahraich, Sitapur, Hardoi, Gautam Budh Nagar Maharajganj, Kushinagar, Gorakhpur, Etah, Aligarh, Sidharath Nagar, Sravasti, Balrampur, Deoria, Balia Una, Kangra Pathankot, Moga, Mohali Sirmour, Solan, Mandi, Lahaul and Spiti Tarantaran, Firozpur, Patiala, Mukatsar, Fazilka Sonipat, Rohtak, Faridabad Pauri Garhwal and Champawat (Tanakpur area) Other districts Bathinda, Barnala, Sangrur, Mansa, Fatehgarh Hissar, Sirsa, Fateihabad, Gurgaon, Jind Other districts Kanpur, Agra, Lucknow, Faizabad, Sulatanpur, Azamgarh, and others Bihar Rajasthan Vaishali Muzzafarpur Ganga Nagar Champavat Hanumangarh Bharatpur ENVIS Uttar Pradesh states. Adequate water availability within these zones and deficit around their boundaries appear to make this distinction in poplar culture. The first zone of concentrated poplar culture lies towards the western limits along the basins of rivers Satluj and Beas in Punjab with some overlapping in plain locations of Himachal Pradesh. The land around and between these two rivers is ideally suited for poplar farming because of easy water availability and sandy loam soil conditions. This zone lies towards higher latitudinal limits within the RIPC and is better suited for poplar culture in comparison with two other zones. It starts around Hoshiarpur in Punjab and extends towards Chandigarh through SBS Nagar and Rupnagar districts on one side and towards Ludhiana district on the other side. The growth and quality of poplar grown in this zone is better and it fetches higher prices in the market. The second major activity of poplar culture is seen around Yamuna and Ganga Rivers and surrounding their basins starting from Himalayan foothills down towards central Haryana and central Uttar Pradesh. This zone overlaps in three states, viz., Haryana, Uttarakhand and Uttar Pradesh and has maximum area under poplar farming. This zone is at a little lower latitude than the first zone, yet has maximum number of wood processing industries and also receives poplar wood from other locations and states. It constitutes Yamunanagar District of Haryana, Saharanpur and Muzaffarnagar districts of Uttar Pradesh and Haridwar District of Uttarakhand. Zone-III lies in the plain region near foothills of Uttarakahnd and Uttar Pradesh states and known as Tarai region. It is a narrow belt between 27o N and 30o N latitudes at an altitude of about 160 to 260 m, along the foothills of Himalayas where water is available at a depth of 1 to 2 m below surface with further having underlying layer of sand and small pebbles to varying degrees. Unlike other two zones, soil at places is very heavy, yet it supports poplar culture on account of good water availability. Poplar (P. deltoides) were initially tested here before their culture was extended to other zones and locations in the RIPC and elsewhere. The zone lies in Udham Singh Nagar in Uttarakhand, and stretches to parts of Uttar Pradesh in Pilibhit and Bareilly on one side and some parts of Rampur on other side. The data gathered on fresh poplar plantations made during the last two years indicates that two third to three fourth of the total poplar planted throughout, is in these three zones. Around 29 per cent of total poplar is planted around Zone-II, 22 per cent around Zone-I and around 18 per cent around Zone-III. Recently, the share of fresh plantations has started increasing in the third zone because many new poplar based wood industrial units have been established in Uttrakhand and many others Forestry Bulletin, 12(1), 2012 have expanded their capacity in Uttar Pradesh. Prices of poplar wood and labour wages are lower in Zone-III favoring increased poplar farming and its usage. Extent of Nursery Production Poplar is grown on non-forest land in many states for which a complete data on the volumes of its saplings production is not available. Till 1994, most of its plantations were grown by the farmers under WIMCO-NABARD refinance scheme. WIMCO was responsible for supplying its saplings to the growers under this project, which is also referred as PPP model, and the wood grown from these trees was purchased back by the company at already disclosed prices. The company was, therefore, the only source for supplying the saplings to the growers till that stage. The number varied from a few hundred in 1976-77 to around 250 thousand during mid 1990s. On termination of WIMCO-NABARD scheme, and with the success of the direct sale of saplings outside, the refinance scheme was started by the company in the year 1993, poplar sapling production expanded among the numerous nursery growers. It also provided opportunity to the separating company staff with technical skills to venture into growing and selling poplar saplings to the growers. As a result, the business of establishing private nurseries started growing. WIMCO, ex-Wimcoites, individual farmers and unemployed villagers are presently the main nursery growers. Haryana State Forest Department has now accelerated its sapling production on increasing demand within the RIPC and elsewhere. Jammu and Kashmir, a hilly state with most of its area land locked between hill ranges, has also started growing sizeable number of poplar saplings for local planting by the growers. There is migration of some of the poplar based industry to this state because of low value of wood available there, which has increased the rate of planting and demand of its saplings within Kashmir Valley. State forest departments in North India have also been growing poplar saplings for making their own plantations on forest land during this period. Some information on the availability of planting stock in U.P. State Forest Department nurseries is accessible from the state website (http://forest.up.nic.in/ plantation.pdf) (Table 2). Similarly a detailed survey of poplar nurseries carried out by the Haryana State Forest Department during 2011-12 provided information on the extent of nursery stock grown in that state (Dhiman and Jagdish Chander, 2012). The total poplar nursery stock presently available in the U.P. State Forest Department nurseries is given in Table 2 indicating that poplar constitutes less than 0.1 per cent (84,099 saplings in 52 nurseries) of the total planting stock (87,632,706 number for 72+ other species in 925 nurseries 17 of 72 forest divisions) grown in the state. The major share of poplar nursery and plantation production in the state is in the private sector which grows poplar saplings as naked root plants in open beds and are called as entire transplants (ETPs) or saplings. Conservative estimates indicate that the private sector has grown around 15 million nursery saplings during the just concluded planting season in the state (Table 2). Among the private nursery growers, WIMCO is a leading player in nursery production throughout the RIPC and is growing 6.5 million saplings this year in its nurseries located in the RIPC. The company has been monitoring the extent of poplar nurseries grown by different sources in different states through its field staff. The information on nursery stock is collected from its field staff posted throughout the RIPC and the estimates of total poplar saplings grown in the state of Uttar Pradesh are given in Table 3. The names and the boundaries of WIMCO’s operational districts do not synchronize with that of the administrative and revenue districts as per government controls but are overlapping with the adjoining districts in many locations. Haryana is one of the leading states in poplar wood usage and also grows appreciable number of saplings for planting within the state and also for supply to some other states (Dhiman and Jagdish Chander, 2012). A detailed survey of all the poplar growing nurseries was carried out by the Haryana State Forest Department which confirms growing of approximately 13.4 million poplar saplings during the year 201112. A major share is grown in the private sector by small nursery growers (Table 4). In the organized sector, WIMCO and the state forest department were the leading nursery growers in term of number and diversity of clones grown in the state. Yamunanagar town is a major poplar growing and its usage centre in the state and the country. Yamunanagar District grows around 60 per cent of total poplar grown in the state. The district is also a main centre for seedling production and their supply to the adjoining states. It receives wood from all other poplar growing states including Punjab, Himachal Pradesh, Uttrakhand and Uttar Pradesh and wood traders also supply saplings to many wood procuring locations. Uttrakhand state (earlier part of U.P.) has been growing poplar saplings from the very beginning when poplar research trials were initiated by the state forest department during the second half of 20th Century. The focus of the poplar programme in the state remained with testing of imported clones and development of mechanized plantations in and around Tarai region. The state has been growing poplar nurseries for own plantations on forest land near Kumaun foothills since 1970s. Presently, the state is growing around one hundred thousand saplings in its nurseries for own Table 2. Poplar stock existing in the nurseries of U.P. State Forest Department S. no. Forest Circle Forest Division Nurseries (no.) Plant stock (no.) Average stock (per nry) 1.1 1.2 Agra Firozabad Mainpuri 1 1 2,000 558 2,000 558 2.1 2.2 3.1 3.2 3.3 4.1 4.2 4.3 5.1 Allahabad Allahabad Fatehpur Azamgarh Baliyaa Mau Bareilly Pilibhit SF Shahajahanpur Basti 1 1 1 4 4 15 1 1 1 700 4,400 300 1,965 1,816 49,776 300 293 1,000 700 4,400 300 491 454 3,318 300 293 1,000 Ambedkar Nagar Faizabad Sultanpur Gorakhpur Etawa Dehat Bulandshahar Total (U.P.) 4 2 8 2 2 2 1 52 2,825 1,360 10,000 8,600 1,050 850 301 88,094 706 680 1,250 4,300 525 425 301 1,694 6.1 6.2 6.3 7.1 8.1 8.2 9.1 Azamgarh Bareilly Basti Faizabad Gorakhpur Kanpur Meerut (Source: http://forest.up.nic.in/plantation.pdf). 18 ENVIS Table 3. Estimated poplar planting stock produced by private growers in U.P. (2011-12) S. no. District Locati ons 1. Saharanpur Saharanpur, Naku r, Deoband, Rampur 2. Mu zaffarnagar Muzaffarnagar, Deob and, Barla, Bhopa, Jansat h 3. Meerut Hastinapur, Mawana, Hapur, Garh, Ghaziabad, Sardan a, Baghpat 4. B uland shahar Toria, Khal out, Bates hwar (Agra) 3 00 ,000 5. Agra Bateshwar 5 0,000 6. Aligarh At rauli 1 00 ,000 7. Moradabad Moradabad, Amroha 8 00 ,000 8. B ijnor Dhampur, Chandpur, Nurpur, Afjalgarh 6 00 ,000 9. R ampu r Milak, Rampur, Chan daushi, Bilaspur, Kemri, Muda Pand ey 3 ,4 00 ,000 10. B areilly Bareill y, Baheri and M eerganj, Aonla, Faridpur, Bhojipura 1 ,0 50 ,000 11. Pilibhi t Maj houla, B isalpur, Ti kri, Amaria, Khamria 5 50 ,000 12. B adaun Datagan j 1 50 ,000 13. Sahajahanpur Kot , Tilhat, Katra, Shehramau, Puvaya, Khutar, Nigohi, Bhawal Khera 5 50 ,000 14. Lakhimpur Lakhim pur, Dharaura, Palia 4 00 ,000 15. Sitapur Tambore, Sitapur 1 00 ,000 16. B ahrei ch Nanpara, Payagpur, Kesarganj, Econa, Bahreich 8 50 ,000 17. Hardoi Kot hava, Badhaul i, Sadabad, Pali 2 00 ,000 18. Stock grown (no.) 4 50 ,000 1 ,3 00 ,000 Others 1 ,2 00 ,000 T otal 15,150,000 planting. Wimco Seedlings operates from Rudrapur, Uttrakahnd and is still the main player for supplying saplings to the growers along with some ex-Wimcoites and other small growers. Maximum private nurseries are located in Udham Singh Nagar and Haridwar districts, some of which also supply saplings to other states. Punjab is the fourth leading state in poplar sapling production in the country. It grows nurseries in different locations. Around one hundred thousand saplings are grown by the government institutions that include Punjab Table 4. Poplar saplings grown in Haryana state during 201112 planting season S. no. 1. 2. 3. 4. 5. 6. 7. 8. 9. 3 ,1 00 ,000 District Yamunanagar Kaithal Karnal Panipat Rohtak Sonepat Panchkula Ambala Kurukshetra Nursery stock 8,129,300 37,500 1,766,000 961,000 37,000 220,000 880,500 1,168,500 234,000 13,433,800 Forestry Bulletin, 12(1), 2012 Share (%) 60.51 0.28 13.15 7.15 0.28 1.64 6.55 8.70 1.74 100.00 Agricultural University, Ludhiana and the Punjab State Forest Department, together. The major share of sapling production is in the private nurseries located in Hoshiarpur, SBS Nagar and Roopnagar districts in the state. Some saplings are supplied to the adjoining poplar growing locations in Himachal Pradesh and Jammu and Kashmir states. Jammu and Kashmir (J. and K.), a hill state, has traditionally been growing poplar. The state grows approximately thirteen to fourteen hundred thousand poplar saplings in the state. Recently, restrictions on transporting planting stock and wood across the state border have been imposed, hence, most of the planting stock is grown within the state itself. Some supplies of the planting stock, however, still take place from the adjoining RIPC to Jammu region where the tree is grown similar to that grown in the RIPC. Private nurseries now grow little more saplings compared to those grown by the Social Forestry Wing of the state forest department. Major share of private nurseries is concentrated in south Kashmir followed by central Kashmir, north Kashmir and Jammu region and Ladakh region. Many cities and locations in Kashmir Valley are affected by typical cotton storms during the dispersal of its seed in spring season. In 19 the last couple of years, the Jammu and Kashmir State Forest Department and state university have been procuring the propagation material of male clones from WIMCO for raising their nurseries and field planting to avoid this problem. The state of Himachal Pradesh (H.P.) has been making planting of around one hundred thousand saplings on the forest land and this planting stock is grown by the state forest department in its forest nurseries. A major share of the planting stock planted by the growers in the plain and in some valley areas of Himachal Pradesh is supplied by the private nursery growers from the adjoining poplar growing locations, like Hoshiarpur, Roopnagar, and Pathankot districts in Punjab and Yamunanagar and Panchkula districts in Haryana. The major part of poplar wood harvested in the state is traded at Yamunanagar wood market in Haryana and Hoshiarpur in Punjab. Both these locations are leading centers for poplar sapling production as well. Wood traders who transport wood from different locations of the state also carry saplings from these locations and supply them to the growers during the planting season. Many of good growers especially near the RIPC also directly procure planting stock from the branded nurseries located in the RIPC. Some private nurseries have also come up in Indora belt of Kangra, plain areas of Una District, Nalagarh area of Solan District, Paonta Valley of Sirmour District and Balh Valley in Mandi District to meet the increasing demand of the growers. In Bihar, poplar saplings have been grown under the centrally sponsored project implemented by the Indian Council of Forestry Research and Education through its institute at Ranchi wherein approximately four hundred thousand saplings were grown in Vaishali District during last year. The state is also planning a Green Mission in which poplar is considered one of the potential species. A few poplar growers in the north Bihar have, however, been directly getting the planting stock from the RIPC for making plantations during the last two decades. Some poplar saplings, in private and government nurseries, are also grown in Chandigarh, Delhi, Rajasthan, and even some northeastern states. There is also a regular movement of poplar saplings from the RIPC to central, north eastern states and other locations during the planting season each year. Extent of Fresh Plantations Poplar has been regularly planted in number of states and locations. Major among them have been hill states of Uttarakhand, Jammu and Kashmir, and Himachal Pradesh where poplar trees in isolated form or in groups could be seen in almost all the hilly districts. Poplar has also been 20 planted in some parts of Delhi, Chandigarh, Rajasthan (Ganganagar, Hanumangarh, Bharatpur districts), north Bihar (Vaishali, Muzzafarpur, Samastipur, Champaran, etc.), north West Bengal and other northeastern states for quite some time now. Poplar plantations on forest lands have mainly been restricted to Uttarakhand and Himachal Pradesh states with some of them grown on road and canal sides, and railwaylines in some states in the RIPC and in hills. Some trial plantations of poplars have also been made in many other central and southern states with suboptimal field performances not at par with that grown in the RIPC. Some figures of poplar plantations on forest land are available from Uttarakhand and Himachal Pradesh. First organized poplar introduction trial plantations were raised in hills and foothill locations of Uttarakhand (earlier part of Uttar Pradesh). The state of Uttarakhand played a significant role in the introductions, establishment and expansion of poplar programme in the country. There were sporadic plantations till 1977 and thereafter, a regular planting was included in the working plans of some of the forest divisions. The trial with introduced clones were tried near foot hills in 1966 and the growth and productivity of those clones was not very encouraging. G3 and G48 clones were introduced 1969 onward which proved very productive for these locations. There was 1,522 ha area under poplar plantation till 1982 (WoP, 1982) and around 3,500 ha by 1999 (Burfal, 1999). Later on Wimco Seedlings established its research base in Rudrapur which helped in its further establishment and expansion of the programme on farm fields. Himachal Pradesh State Forest Department has been planting poplar since long. P. ciliata is largely planted on forest land by the state forest department and to some extent by the research organizations in their research trials. The interest in poplar as a plantation species dates back to 1950s when planting of P. ciliata along with some introduced species were explored as a nurse crop for regeneration of fir and spruce forests in the state (Agarwal and Patil, 1956). P. ciliata with introduced P. monilifera and P. generosa were tried and proved useful in regenerating fir and spruce in Kullu District but could not be replicated on a large scale. P. deltoides, is the main preferred species in poplar culture in the state. It finds favour among all growers, viz., farmers, state forest department and research organizations for growing in locations from cold desert to Himalayan foot hills and valley areas. It is mainly planted in Balh Valley of Sundar Nagar, Mandi District, Mand belt (Indora Division) of Kangra District, lower areas of Una District, Nalagarh Division of Solan District and Paonta Valley of Sirmour District. The ENVIS species was also introduced in the Spiti cold arid region during early 1980s and some of its plantations are better grown than many plantations of other species. The main cultivars of poplar commercially grown in the state are the same which are grown in the RIPC. These include G48, Udai, WSL 22, WSL 39, etc. with some last year released clones specifically WIMCO 81, WIMCO 83 and WIMCO 110 are also now finding favour among the growers. UHF has developed and recommended some clones of poplar for growing in the state (www.yspuniversity.as.in). Himachal Pradesh has documented plantation figures of poplar and other tree species made from 1950s and posted them on its website (http://himachal.gov.in). Out of a planted area of 1,026,776 ha under different schemes till date (w.e.f. 1950 to 2009-10), poplar plantations cover 14,958 ha which represents 1.46 per cent of the total plantations made in the state so far. Many of the species planted in the state are slow growing conifers and broadleaved species, the share of poplar and willow planted area is, therefore, likely to be very low as most of the earlier planted poplars could have lived their physical age or could have been harvested. The tree is highly sensitive to moisture status of planted sites, the initial and final survival is likely to be lower than the hardy conifers and some broad leaved trees. The state raises plantations with around 20 million plants per year, out of which poplar constitutes 0.58 per cent of total planting. During the last two years, there were 21 plantation schemes, out of which poplars were planted in 12 schemes. CAT plan had maximum plantation of poplars (28.40 per cent) followed by backward area sub plan (19.37 per cent), improvement of tree cover (12.93 per cent), plantation under MHWD project (9.08 per cent), soil conservation (7.61 per cent), enrichment planting (5.83 per cent), compensatory plantations (5.31 per cent), pasture development (4.57 per cent), reforestation of scrub areas (2.95 per cent), macro management (RVP) (1.66 per cent) and FDA samridhi yojna (0.56 per cent) (http://himachal.gov.in). Circle-wise data of poplar planting during these two years further confirm that poplar is planted for diverse purpose. Bilaspur and Hamirpur forest circles located in the lower Himachal Pradesh have some poplar plantations by the private growers though government figures do not show any planting in those areas. The plantation figures further confirm poplar planting under wildlife and watershed programmes. Kullu Forest Circle leads in the state with planting of 41.18 per cent of total poplar on government forests followed by Rampur (20.22 per cent), Shimla (9.70 per cent), MHWD Project (9.08 per cent), Wildlife Shimla (8.26 per cent), Nahan (5.96 per cent), Chamba (4.19 per cent), Dharamsala (0.76 per cent), wildlife Shamshi (0.76 Forestry Bulletin, 12(1), 2012 per cent) and wildlife Dharamsala (0.27 per cent) of the total poplar planted in the state (http://himachal.gov.in). Poplar was one of the main tree planted in a centrally sponsored programme - Desert Development Project which was launched for Spiti Division of Lahaul and Spiti District in 1978 and for Pooh Division of Kinnaur District in 1982 with special emphasis on rehabilitation of cold desert. Under this programme, 1,636,735 plants were planted over 830 ha (Negi et al., 1996). Two regional centers of UHF, viz., RHRS, Jachh and HRRS, Dhaulakuan and its main campus at Solan have been producing poplar saplings for own use and to supply them to tree growers of the locality since mid 1990s. According to Chauhan (2012) Jachh and Dhaulakuan centers have produced and supplied 89,207 and 163,305 saplings respectively till date (total 252,512). The annual supply is worked out to be 8,600 saplings from Dhaulakuan and 5,500 saplings per year from Jachh, respectively. The university had a saleable stock of around 800 fully grown poplar trees that was put to auction during 2011. Himalayan Forest Research Institute is also raising poplar and willow nurseries which have been established in different locations including cold desert region. Some poplar has also been planted by the Public Works Department (PWD) along road side especially along national highway around Solan town. Major share of poplar in India is planted in the RIPC. Though planting season is restricted to winter months, its harvesting and usage is spread throughout the year. It is harvested, transported, traded and used on day to basis. Harvesting decisions are driven by financial needs of individuals than strong silvicultural options. It is extremely difficult to capture these frequent changes from such a wide geographical area controlled by many states. This many a times has already affected the industry and growers by widening gap between demand and supply and also in crashing of its prices due to glut like situation in the market. National Poplar Commission, quoting Forest Survey of India, has reported 312,000 ha area under poplar in the country (NPC, 2012). Forest Survey of India first time reported inventory of 75,807,000 number poplar stems (with further classification into size classes as 74,150,000 in 10-30 cm dbh class, 1,644,000 in 30-50 cm dbh, 7,000 in over 50 cm dbh class) in its 2011 report which collectively represent 1.50 per cent of total stems recoded as ToFs in the country. The report further confirms the volume of 11.159 mm3 of poplar trees in 10-30 cm dbh, 1.260 mm3 in 30-50 m dbh and 0.023 mm3 in over 50 cm dbh class for all the poplar trees as ToFs in the country. The total volume of poplar trees as ToFs is reported as 12.402 21 mm3 representing around 0.8 per cent of total volume in ToFs in the country (IFSR, 2011). The districts once selected for surveying is likely to be surveyed after 10 cycles (20 years) with a further possibility of 25 per cent already surveyed districts being selected for saplings after eight years as per sampling procedure followed by the organization. The survey is based on the interpretation of photo-imagery recorded during October 2008 to March 2009. It records trees only over 10cm dbh class and when the harvesting of poplar in many locations is now being carried out at a young age as early as of four years. Many of the poplar trees thus get harvested even without getting a documentation in this report. These figures are just indicative numbers projected from limited information collected from limited sampled districts (178 districts from 2002 to 2009) and do not have much practical significance. The author, therefore, has been relying more on the interpretation of information collected on the nursery stock grown and that fresh planted in different locations. Most of this information is being regularly published for the benefit of others The information collected for the planting season 2011-12 from different locations is presented in the Table 5, which indicates that Uttar Pradesh is the leading state for growing 38.61per cent of total poplar in the country followed by Punjab (18.01 per cent), Uttarakhand (16.95 per cent), Haryana (16.33 per cent), Jammu and Kashmir (3.85 per cent), Himachal Pradesh (2.49 per cent) and other with collective share less than 5 per cent. A major share of poplar in Punjab is grown in compact blocks, whereas Jammu and Kashmir grows most of its poplar as shelterbelt around fields and orchards. The trend is mixed in most other states and is ever changing with change growers from year to year. These figures are again not absolute values on the status of surviving stems which undergoes a change every time, based on numerous factors. Based on the above, published information and that collected from the field staff and personal contacts from different states, it is inferred that a total nursery stock grown in the country was 48 million, out of which around 25 per cent remain unsold especially from the low quality nurseries (WSD, 2011) (Table 6). Around 10 per cent stock is kept for multiplication for making next year nurseries. Further it is inferred that maximum poplar is planted on the farm land in association with agricultural crops and the share of poplar planted on forest land is very negligible. Like sapling production, there is also no database available for field planted poplar from most of the states. Table 5. Estimated number of poplar saplings planted during 2011-12 planting season State Planted in block Per cent of Per cent of total state (No.) Jammu and Kashmir Planted on boundary or row (No.) Per cent of Per cent of total state (No.) Total Per cent of total 100,000 0.56 8.33 1,100,000 8.17 91.67 1,200,000 3.85 Punjab 4,317,700 24.38 76.90 1,297,000 9.63 23.10 5,614,700 18.01 Haryana 2,635,000 14.88 51.77 2,455,000 18.23 48.23 5,090,000 16.33 430,000 2.43 55.48 345,000 2.56 44.52 775,000 2.49 Himachal Pradesh Uttarakhand 2,625,000 14.82 49.67 2,660,000 19.75 50.33 5,285,000 16.95 Uttar Pradesh 7,253,800 40.96 60.26 4,784,500 35.53 39.74 12,038,300 38.61 Bihar 110,000 0.62 24.44 340,000 2.52 75.56 450,000 1.44 Rajasthan 115,000 0.65 51.11 110,000 0.82 48.89 225,000 0.72 Others 125,000 0.71 25.00 375,000 2.78 75.00 500,000 1.60 Total 17,711,500 100.00 56.81 13,466,500 100.00 43.19 31,178,000 100.00 Table 6. Estimated number of poplar saplings grown in nurseries and field during 2011-12 State N ursery (N o. in hundred thousand) G overnm ent sector P rivate sector T otal F ield planting (N o. in hundred thousand) G overnm ent sector P rivate sector T otal Jam m u and Kashm ir 4.00 9.00 13.00 0.00 12.00 Punjab 1.00 71.00 72.00 0.00 56.25 56.25 20.00 114.00 134.00 0.00 5.00 51.00 H aryana 12.00 H im achal Pradesh 1.00 8.00 9.00 1.00 6.75 7.75 U ttarakhand 2.00 90.00 92.00 2.00 51.00 53.00 U ttar Pradesh 1.00 150.00 151.00 0.00 120.00 121.00 B ihar 4.00 0.00 4.00 0.00 4.50 4.50 O thers 1.00 3.50 4.50 0.50 5.00 5.50 T otal 34.00 445.50 479.50 3.50 260.50 311.00 22 ENVIS Nursery Production Poplar is normally propagated by using hardwood stem cuttings collected from the last year nursery grown juvenile saplings. Stressed and desiccated cuttings or those collected from mature trees sprout late and cause variation in the nursery stock. Cuttings are planted in well prepared open nursery beds during January-February. With normal cultural operations of earth working, irrigation, weeding, and tending; saplings attain an average height of 3-6 m or sometimes more based on inputs and cultural operations provided to the nursery. Approximately 20,000 saplings are produced in an hectare nursery area. WIMCO now uses a different approach for growing saplings in its nurseries. The plantlets are first grown using reproduction means discussed above which are then planted in open beds any time till July depending upon the size of the saplings required in a particular locality (Dhiman and Gandhi, 2010). The saplings grown by the new means continue to grow sometimes till first week of November, remain in leaves till last week of December, lateral buds rarely sprout during the active growth period, have better diameter/ height ratio and looks fresh with soft bark compared to those planted by traditional stem cuttings route during January February. Terminal bud setting in traditionally grown saplings generally starts during the last week of October. Plantation Establishment Saplings are lifted during January and February, conditioned in fresh water for around 48 hours and are field planted after their nursery growth. The planting period is sometimes advanced to December and also extended to the first week of April depending on land preparation, occupation of fields with intercrops and other field conditions. The recent experimentation of planting poplar October onwards with certain innovations proved encouraging. Based on around half a dozen field trials across the RIPC, early planting of poplar saplings is now a reality and is being demonstrated to the farmers throughout the RIPC. Poplar is planted inside and around agricultural fields. Land preparation near to poplar planting time, followed by one or two timely irrigation has a significant effect on initial survival of poplar. It is planted in augur made 7-10 cm round and 60-90 cm deep pits. Poplar develops major root system near the surface and the deep planting is followed for anchoring the trees against strong winds. On putting the sapling in the pit (hole), 3/4th of the pit is filled with top soil mixed with appropriate nutrient mixture that depends on the fertility of the soil. The fields are irrigated with surface water to an extent that some water stands inside pits which helps in settling the filled soil inside the pit. The remaining empty pit Forestry Bulletin, 12(1), 2012 is filled after around a week with fresh soil and again irrigated for settling the soil. Irrigation, thereafter, is provided to agricultural crops till summers when additional irrigations are provided if intercrops are not grown along with poplar. Poplar is planted over a wide range of spacing and patterns. The most common spacing adapted are 5x5 m or 5x4 m or 7x3 m or 8x3 m in blocks and 2-3 m apart in lines and boundary plantations across the poplar growing region. Wider spacing favours growing agricultural crops with higher yields for longer period then closer spacing. Poplar grown in block plantations produces better quality timber with circular stem, less knots and other defects and therefore fetches higher price in the wood markets. Silviculturally, poplar grows better under mild competition in stands, whereas, trees tend to become branchier, if planted wide apart especially on boundaries. Experienced farmers who have grown it for 4-5 rotations by now still prefer to grow it in blocks for getting better returns and appreciation of their good quality timber value. Poplar timber from the state of PB still fetches relatively higher price in Yamunanagar (HR) poplar wood trading centre as most of it is grown in compact blocks in that state. Poplar Based Agroforestry (PBA) Growing intercrops is a normal practice and some aberrations of keeping fields without intercrops may occur occasionally. Crops grown in PBA are locality specific and originated through farmers innovations as these have been associated with their sustenance and life support system. Over 98 per cent poplar block plantations have been recorded to grow intercrops which vary with locality, age of trees, prevailing market conditions, season and economic conditions of the farmers (Dhiman, 2012). Farmers grow only those new crops which provide better returns compared to those traditionally grown by them (also see Chauhan et al. in this volume). Plantation Management Poplar is grown on agriculture fields and is a domesticated tree in India. It is grown on farm land with so many growth contributing variables in planting stock type, intercrops, cultural inputs, tending operations, insects and pathogens, climatic, edaphic and geological constituents that its productivity on any site is likely to vary with variation in any of these variables. The impact of these variables on poplar growth is easily exhibited in a very short span since the tree is very fast grown, and responds quickly to any of the management intervention. Higher timber productivity of 26.46 m3 per hectare per year recorded for poplar on farm land 23 compared to just 13.65 m3 per hectare per year on forest land (Singh and Jhajaria, 2001) justifies the importance of management inputs applied in the fields having both tree and intercrop culture together. Better growth of poplar obtained along water channels and poor growth in fields with top soil scraped and also on uncultivated fields indicate that even small changes in any of the growth variables has significant impact on the overall productivity of poplar. Variable silvicultural quality of the planting stock of same clone grown in different nurseries showing differential field survival and growth justifies the claim of higher sale price for its saplings by certain branded and established nursery growers. A good agriculturist has been proved a good tree grower since he better understands the needs of both intercrops and trees than most of the absentee land owners and casual growers due to their casual approach on poplar farming. Dhanda and Verma (1995) reported productivity of poplar grown with intercrops in PBA as 444.1 m3 at years with MAI of 49.3 m3 per ha per year and 292.0 m3 at five years rotation with MAI of 58.4 m3 per year and indicated the reasons for this variation in productivity due to harvesting age, management inputs and locations of fields along river beds or away on upland. The data on poplar farming available from other locations especially, Bihar (Dhiman, 2010b), Chhatishgarh (Puri et al., 2002; Mishra et al., 2004), and Maharashtra (Gogate and Deshpande, 1994) indicates lower growth and yield compared to that obtained in the RIPC. These warmer and drier sites are located at much lower latitudes than that of 28oN lower latitudinal limit for P. deltoides in its natural range in the USA and in its introduced locations in the RIPC. In addition, better agriculture production facilities and system in the RIPC encourages better growth of poplar and intercrops in this region. Pruning poplar trees is an essential component of plantation management for improving the quality of timber and also to protect them from wind damage by reducing wind pressure on their crown. Wind damage to poplar is common throughout the RIPC. Generally, young trees of 12 years age get broken from the main stem, whereas, old trees get uprooted or bend with the wind pressure. In many locations, fields inundate with water for many days during rainy season forcing trees to bend or fall with gentle wind pressure. Two types of pruning are in vogue, namely lateral pruning and vertical pruning. The former is used to facilitate apical growth by lengthwise trimming lower side branches/ shoots just after planting and also to reduce wind pressure by reducing the crown size. Lateral pruning is again applied during tree dormancy stage in the following two winter seasons. Vertical pruning is used for improving the wood quality by selectively removing co-leaders and a few thick 24 branches in the first and second year winter season and thereafter in alternate years to lift the crown to the stem thickness of around 30 cm girth since logs below this size are sold as firewood. In some locations, farmers have developed thumb rules to prune trees to the height near the transition of smooth bark to corky one. In lateral pruning, all lower branches are half cut, whereas, in case of vertical pruning thick branches are cut touching main stem with sharp tools. Lateral pruning is increasingly applied in wind prone areas, whereas, vertical pruning is applied throughout the RIPC. Anchoring trees with the support of ropes is a regular practice in many flood prone areas having heavy soils to save them from lodging with wind pressure. Young dislodged trees during rainy season are heavy pruned, erected and tied with ropes and many of them survive and grow till their final harvesting. Poplar is normally harvested during pre- and postwinter cropping seasons in order to avoid damage to agricultural crops standing in the fields. For harvesting trees, the basal thick and side roots of the trees are exposed, cut with axes and the trees are made to fall on one side with their main root system (Fig. 1). Left over tree parts including roots are immediately cleared to make fields ready for growing next season crops including fresh poplar plantations. Of late, some farmers have started keeping their poplar fields free from agricultural crops during the harvesting year to take advantage of escalated wood prices during off-season harvesting season. Poplar trees grown on field boundaries sometimes felled without uprooting and many farmers now manage the coppice shoots arising from the stumps as a fresh crop. Like other trees, coppicing in P. deltoides also depends on age, season and clone type (Sharma et al., 1996). Poplar harvested during monsoon or winter season coppices well, whereas, its capacity to give new shoots decreases significantly in hot and dry season. All stumps do not sprout and some gaps are created which the farmers try to fill with fresh planting or simply ignore gaps created after felling. As a result, the quality of wood produced from such coppice origin trees is poor because of high degree of branching, knots, and taper and it fetches low value in the market. The proportion of the coppice origin poplar is now increasing and constitutes a fairly significant component of poplar culture; i.e., approximately 5-8 per cent of total standing poplar in the RIPC (Fig. 2). The share of coppice origin poplar is more towards eastern limits of RIPC and also in some locations within this region where some casual poplar growers and those with low land holdings and poor economic conditions retain coppice shoots to avoid expenditure on making fresh plantations. ENVIS Rotation and Yields Poplar is extremely fast grown and attain marketable size timber at very young age. It is generally harvested at six to eight years of rotation which sometimes is extended from four to twelve years. The tree is mainly grown as a cash crop for sale of timber to wood based industry. The main factors that determine the harvesting age of trees are the economical conditions of the grower, his immediate financial needs, market conditions, land holding size and his interest in agricultural crops. Farmers, in some locations where market for the under sized wood is now well developed, have started harvesting poplar at even four years of age to take early advantage of fluctuating wood prices in the market and also realize better value for cash intercrops like sugarcane which could be economically grown at the young age of trees. Farmers with good land holding size and better economic conditions prefer to harvest trees at old age and get better appreciation of the timber. Some farmers also postpone harvesting of trees to later age if the prices of wood are low in the market. Good growing plantations attains 5 m average height and 5 cm average diameter per annum with a ratio of around 100:1 for the first half of the rotation age of poplar growth. Current annual and mean annual increments culminate at a very young age in poplar (Fig. 4) in comparison to most other forest tree species. Current and mean height growth culminates faster in comparison to current and mean diameter growth. Dhanda and Verma (1995) reported that MAI of DBH is more for boundary trees (5.2-9 per annum) than in block plantations (3.8-7.8 cm per year). Poplar logs of thick girth size are sold at higher prices throughout the RIPC. Percentage of logs with thick girth sizes increases with increase in the harvesting age of trees. A comparison of six plantations harvested at different ages from five years to 10.5 years during 2011 surrounding Bareilly location, Uttar Pradesh and monitored for log size-wise yield including that of firewood is given in Tables 7 and 8 (Fig. 3). The ratio of over (over 60 cm mid girth) and under size logs (between 50-60 cm mid girth) varies from 55 per cent in 5 years old trees to 95 per cent in 10.5 years old trees. Marketing Poplar logs are usually processed when these are fresh. The wood is harvested during the day hours, transported to the local wood markets or industrial units during the night and auctioned/sold in the early morning hours. Almost all components of poplar trees including logs, roots, lops and tops Table 7. Timber volume (cmh-ub) in selected plantations with different harvesting ages Location Age (yrs) Tree (no.) Log. vol. (cmh-ub) for logs Ratio for mid with mid girth girth logs Timber vol./tree(cmh-ub) (>60cm) (<60 cm) (<60/>60) (>60cm) (<60 cm) Total (mid girth) (mid girth) (mid girth) (mid girth) (mid girth) Atrauli, Aligarh, U.P. 8.5 2,880 1,534 82 94.93 0.533 0.028 0.561 Bhuta, Bareilly, U.P. 7 2,200 216 114 65.45 0.098 0.052 0.150 Shahajahpur, U.P. 6 630 62 30 67.39 0.098 0.048 0.146 Hardoi, U.P. 5 225 17 14 54.84 0.076 0.062 0.138 Bareilly, U.P. 5.5 170 16 8 66.67 0.094 0.047 0.141 Milak, Rampur, U.P. 10.5 150 82 4.5 94.80 0.547 0.030 0.577 Table 8. Total tree yield (by weight) in selected plantations with different harvesting ages Loc ation A ge ( yrs) Tr ee (no.) (>60c m) (m id gir th) L og we ight in qtls (< 60 cm ) 30-50 c m Fir e wood (m id g irth) (mi d gir th ) W e ight in qtls Total P e r tr ee Atrau li, A liga rh, U.P . 8.5 2,880 2.16 0 .4 0 0.91 1.24 4.71 4.71 Bhuta, Barei lly, U .P. 7 2,200 1.53 0 .8 1 0.80 1.00 4.15 4.15 Sha ha ja hpur, U .P . 6 630 1.48 0 .7 1 0.70 0.90 3.79 3.79 Ha rdoi , U.P . 5 225 1.16 0 .9 6 0.71 0.87 3.69 3.69 Barei lly, U .P. 5.5 170 1.36 0 .6 8 0.70 0.94 3.69 3.69 Milak, Ram pu r, U .P. 10.5 150 8.50 0 .5 0 0.67 0.67 10.33 10.33 Forestry Bulletin, 12(1), 2012 25 along with bark separated at processing sites or at harvesting sites are sold in the market. These are sold on weight basis which is recorded just before finalizing the deal for sale/purchase. Any delay in its sale results in weight loss due to loosing moisture and ultimately low value for the produce. The weight loss in logs is fast on thin logs and firewood than thick logs. Approximately 16.23 per cent overall weight loss was recorded in 35 days period from different components during the month of October (Dhiman, 2012). The growers therefore prefer to sell fresh wood on day to day basis. The wood is sold in around a dozen wood markets where rates for each thickness and quality grade (mainly based on knots and straightness) change on day to day basis. Yamunnagar in Haryana, Hoshiarpur in Punjab, Rampur and Hapur in Uttar Pradesh are the well established main markets for trading poplar wood and are also barometers for the poplar wood prices to local growers. Many wood based industrial units also make direct contacts with the poplar growers, purchase trees on lump-sum deals or weight basis and arrange their harvest and transport. The log grade is decided on its girth, namely over grade with girth thickness +60 cm, under grade with 50-60 cm girth thickness and ‘sokta’ with 30-50 cm girth thickness. The wood is also sold as a mixed lot of all tree components together and it attracts lower value than the graded lots. The thickness limits and their measurement points like thin, thick or mid end of logs have been changing over the years with ever changing demand and supply scenario of its wood in the local markets. These limits tighten during the period of surplus supplies and relaxed during the period of scarcity. Thick logs are usually used for peeling purpose and thin logs for making filling material for ply-board. Billets below this size, roots, lops and tops are sold as pulpwood and firewood. Wood is also traded on volume basis(cmh-ub) in forest corporations of a couple of hill states where some of it obtained from trees grown on government land is periodically auctioned from their wood depots around winters. Numerous traders have developed their business throughout the RIPC and farmers are at ease in selling most of their plantations on lump-sum basis to them. The entire operations and controls thereafter are arranged by the contractors. These contractors supply wood to main contractors operating from the main marketing centers which charge a percentage of commission from the sub contractors and supply wood to the industrial units on day to day basis. There is a lot of movement of poplar wood within and the RIPC (Fig. 4). Economics Poplar based agroforestry is reported to be economically viable and more profitable than many other land use options with minimum risks (Jain and Singh 1999, 2000; Dhillon et al., 26 2001). Economical returns from poplar farming depends on a very large number of factors of which tree harvesting age, density and geometry of tree planting, land-use (forest or farm land), clone type, intercrops, plantation management, cultural inputs, market prices for input material and farm produce both of trees and intercrops at certain period of time are the major contributors. There have been numerous attempts from the very beginning of poplar culture on forest and farm land to estimate its economic viability. The economic viability of first large scale poplar plantation established over 20 ha forest land in 1966 and harvested in 1981 was reported to have 28 per cent internal rate of return and B:C ratio of 3.19 per cent at 13 per cent rate of interest (Chaturvedi, 1982a and b). The economic returns from poplar culture with and without intercrops were reported to vary with tree rotation (Mathur and Sharma 1983). For 8 years rotation, higher B:C ratio of 3.22 was reported for poplar culture on farm plantation with intercrops compared to 2.15 for forest plantation and with intercrops and 1.51 for forest land without intercrops (Mathur and Sharma, 1983), whereas, Dhillon et al. (2001) reported cost benefit ratio of 1: 1.92 and 1: 2.13 for pure poplar and for poplar and intercrops together. Cost benefit ratio on farm land at eight years rotation was reported as 1.86 and 1.70 for 12 per cent and 15 per cent discount rate of interest by including Rs. 5,000 as opportunity cost against a net loss due to agricultural crops (Chandra, 1986). Singh et al. (1988) reported that five year old poplar planted at 5x4 m spacing along with mentha intercrop under agroforestry gave net returns of Rs. 44,385 per ha through trees and Rs. 65,886 through crops. The single row plantation along with field bunds gave a net return of Rs. 11,067 per ha and Rs. 41,250 per ha over a period of three and seven years, respectively. Benefits from raising nursery stock are much higher (100.9 per cent) within one year (see Kiswan and Dinesh Kumar, [n.d.]). The economical returns from poplar farming fluctuates with marketing conditions for sale of tree and intercrop yield components. There are daily, monthly, seasonal and annual variation in wood prices and these affect returns to poplar growers during the sale of their produce. Any change in the demand and supply system that even affect daily supply of the wood to the market affects its prices. The sale value of the wood from the plantations given in Table 8 based on the prevailing market rates during their sale time is given in Table 9. It is evident that the value of trees increases with age of harvesting, though the farmer has to incur some loss on loosing the yield of crops if trees are retained for long period. PBA has already established benchmarks of high economical returns in agroforestry systems practiced in ENVIS Table 9. Economical returns (Rs. per tree) from selected plantations with different harvesting ages Location Age (yrs) Tree (no.) Atrauli, Aligarh, U.P. Bhuta, Bareilly, U.P. Shahajahpur, U.P. 8 7 6 Hardoi, U.P. Bareilly, U.P. Milak, Rampur, U.P. Fire-wood Total value (per tree) 365.83 320.00 280.00 148.88 120.55 108.00 2,480.33 2,151.45 1,997.52 573.33 284.44 104.00 1,886.22 409.41 300.00 280.00 266.67 112.94 80.00 1,894.12 7,446.67 (>60cm) (<60 cm) 30-50 cm (mid girth) (mid girth) (mid girth) 2,880 2,200 630 1,728.33 1,225.45 1,180.95 237.29 485.45 428.57 5 225 924.44 5.5 10.5 170 150 1,091.76 6,800.00 India. Many of the average poplar growers are now realizing around Rs. one hundred thousand per acre per year (one US $=Rs. 53) net returns from PBA when its timber prices have touched all times high prices for over size logs as Rs. 1,100 per quintal in Yamunanagar, Haryana a poplar market. There is also a shift for harvesting poplar early at even four years age in some locations with the sole objective that growing of cash crops like sugarcane becomes uneconomical when the net returns per unit area and per unit time decreases after two harvests - the 2nd harvest being ratoon (coppice) origin. Appreciation of prices for even undersize poplar wood harvested at young stages is also motivating for this change. Growers are getting a lump sum amount from the sale of poplar trees. Many growers believe that the income from the trees is net profitability from the PBA and the expenses from the beginning of poplar and intercrop culture in a rotation period are recovered from intercrop yields itself. Money received from the sale of poplar and intercrops being agriculture income is treated tax free and many growers have gainfully used it for diversifying their business activities and making assets. Usage Poplar wood is used for manufacturing around three dozen products (Dhiman, 2004). Poplar has now developed a complete use of its all tree components (Table 10). Even leaves and foliage with thin branches are lopped and converted into chips for sale to wood based industry as fire wood. Paper pulp is the third major use of poplar wood after panel industry and firewood in India (Fig 5). Fiber dimension, proximate chemical composition (Milea, 1980), and characteristics of lignin (Singh et al., 1982) and hemicelluloses (Singh et al.,1982) in poplar wood make it one of the favored raw material for making paper of different grades, viz., wrapping /writing paper (Einspahr et al., 1970), grease proof paper (Rai and Ilam Chand, 1988), and news print (Singh et al.,1981). Poplar is not grown Forestry Bulletin, 12(1), 2012 exclusively for paper pulp and it is either the industrial wood waste or the left over material from plantations that is used as pulp wood. Most of poplar wood collected from sawmill waste, veneer waste, plywood trimming, and especially those parts which are not used either for sawing and peeling in poplar based industry are accepted raw material by the paper industry. From trees, only those rejected wood pieces with heavy defects like knots, bends, hollowness and those billets below 45 cm mid girth up to 30 cm mid girth or sometimes even less than that find use as raw material for paper and pulp industry. Poplar wood was exceptionally used for making paper by many paper industrial units within RIPC and as far as South India during 2003-05 when its prices were very low due to reduced demand on temporary closure of veneer industry. Poplar protection Two chapters, one each on insects and diseases are specifically devoted in this issue (see Ahmad and Faisal; Singh et al.). However, poplar being a very fast growing tree species is affected by numerous other biotic and abiotic agents (Table 11) of which the damage from wind, fire, insects, diseases, animals, and birds sometimes attain economical proportions. However, there are numerous other biotic and abiotic agents which cause damage to poplar, some of which have been documented (Dhiman, 2011) and some others are identified separately through a diagnostic survey conducted among the progressive growers and its results reported here. A diagnostic survey was conducted among 178 progressive poplar growers and leading nursery Table 10. Commercial and domestic use of poplar tree components S. no. 1. 2. 3. 4. 5. Tree part Leaves/foliage Bark Branches Stem Roots Use Fodder, and firewood on chipping Firewood, and carrier for mosquito quails, etc. Firewood, pulpwood and timber Timber, firewood, and pulpwood Firewood, and timber 27 Evolving Business Models in Poplar Culture Many farmers are now reporting lucrative returns from poplar nursery and plantation. Poplar culture, primarily in the private sector, is mainly driven by the economic considerations from the sale of nursery saplings to trees/wood. Besides the regular growers, poplar culture, over the last two decades, has evolved as business opportunity and a mean of self employment for numerous farmers and non-land owners. It is also an excellent opportunity to remain engaged in poplar related activities for remunerative returns. One such real case study indicating handsome net returns of Rs. one hundred thousand from 0.4 ha-1 yr-1 from PBA with cultivation of traditional sugarcane and wheat crops under poplar plantation is presented in this volume (Chaudhary and Chaudhary in this issue). There are numerous other growers with experience of even better returns with introduction of summer intercrops and even high value crops throughout the RIPC. There are numerous variants of business models in poplar nursery production, trading in saplings, plantation production and maintenance, wood trade including outsourcing in all these activities. Business models with variations exist in nursery production both on private land and hired land such as selling the entire nursery on hectare basis on lump-sum deals much in advance of lifting the saplings, their delivery on negotiated price without and with support in getting them planted on farmer’s land by both the nursery growers and service providers with variable earnings from commissions or margins. Many nursery growers and traders are trying to reach the growers and markets to make their business models financially lucrative. For example, large scale selling outlets are created during planting season on the road heads at number of locations across the RIPC. A couple of cases have also recently emerged in Uttar Pradesh. where some absentee landlords and even some businessmen have taken up poplar plantations through service providers with the condition that the saplings to be used for planting on their fields are procured from the branded nurseries and the payment is released only on presentation of receipts of sapling purchase and also when the service provider has ensured expected final survival of planted saplings. The margin money for the service provider in this case is higher but the growers are happy in ensuring better survival and expected returns from their plantations. Similar variants also exist in growing poplar plantations which are grown on hired lands for different years with variable terms and conditions. One such real case is summarized below (Dhiman, 2012). Mr. R. Singh took up poplar plantation as a business on leased land from one of his old known farmer in Pilibhit District in U.P. during 2004 when poplar prices were very low in the market. He entered an unwritten understanding with the farmer that the former will pay Rs. 15,000 from 0.4 ha-1 yr-1 for seven years to the latter during the beginning of each year. Mr. Singh planted 500 saplings of WSL 22 at 4.5m x 4.5m spacing in February, 2004 and finally harvested 95 per cent of the trees, in April 2011. Farmer took up sugarcane in the first two years and wheat, thereafter, till sixth year as intercrops at his own costs. Mr. Singh pruned the poplar trees during the second, fourth, and fifth years as practiced in the area. There was no cost involved in pruning and the labourers got the pruned branches as fuelwood free of cost. Mr. Singh spent Rs. 8,000 on cost of saplings and Rs. 1,500 on its planting during the first year. The cumulated cost when compounded to 7 per cent inflation was Rs. 26,215, Rs. 44,100, Rs. 63,237, Rs. 83,714, Rs. 105,624, Rs. 120,624, Rs. 129,067 and Rs. 154,152 at the end of year 1, 2, 3, 4, 5, 6 and 7 respectively. Total cost of production on 2 acre poplar plantation compounded with 7 per cent inflation was Rs. 271,552 that also includes an expenditure of Rs. 117,400 on harvesting of trees. The sale proceed from timber, roots and firewood was Rs. 1,150,472 from 0.8 hectare giving him a net profit of Rs. 878,920 in seven years and Rs. 62,780 from 0.4 ha-1 yr-1 with provision of 7 per cent inflation. The cost-benefit ratio is calculated as 1:3.24 with- and 1:3.40 without- considering 7 per cent inflation. Similar variants with some modifications of understanding and arrangement for growing poplar as business opportunity exists in different parts of the RIPC. One landless entrepreneur in Udham Singh Nagar, Uttarakhand has been regularly growing poplar on leased land for over a decade period now. He is taking land on lease for 6-7 years, making and maintaining poplar plantation himself but subletting intercropping to other growers at some lease amount. Presently, he is earning Rs. 3,000 from 0.4 ha-1 month-1 as income. He is having number of plantations under this arrangement. The present poplar wood prices are in the upper band and fluctuate periodically, seasonally, and daily. Some experienced entrepreneurs’ have now learnt the trick of the trade to take up the lands on hire when poplar wood prices are low in the market and many of the growers restrain from planting at that stage. 28 ENVIS Table 11. Major causes of damages to poplar S. no. Cause Agents causing 1. Abiotic agents Major damage Wind, fire, floods, hails 2. Animals and birds Blue bull, monkeys Rabbits, rats, pigeons, crows, wild bores, porcupines. 3. Insects 4. Pathogens Leaf miner, bark borer, stem borer, san jose scale and others Fungi causing leaf spots, cutting rot, bacteria causing canker Thefts Ipomea sp. 5. Physiological Clostera species, red mite, termites, shoot borer, leaf sap sucking insects, mango mealybug Fungi causing leaf blight, blistering, set rot; damping off to seedlings; MLOs causing flattening Zn and S deficiency, moisture stress 6. 7. Human beings Parasites Physical damage during cultural operations Mistletoe, Cuscuta spp. Minor damage Sun scorch, high temperature Bark burst Table 12. Biotic and abiotic agents causing damage to poplar Biotic and Abiotic agent Wind storms Water stress (both excess and deficit) Blue bull Termites Shoot/stem borers Theft and damage for revenge Clostera spp. (poplar leaf defoliator) Fire Root rot Monkeys Zinc deficiency Leaf spots Sap suckers including red mite Mealybug Hails damage Flattening Sulfur deficiency Domestic animals Leaf miner Blistering Poplar fever Others Rats Parrots Crows Punjab 1 2 14 3 8 16 7 6 4 12 5 10 18 15 9 23 11 24 17 19 20 25 22 13 21 growers in four states, viz., Punjab, Haryana, Uttarakhand, Uttar Pradesh, and throughout the RIPC to identify the agents responsible for damages to poplar as perceived by the growers. Response was obtained on a format having listing of 25 biotic and abiotic agents (Table 12) and the respondent were requested to enlist them in the order of their potential to cause damage to poplar nurseries and plantations. The overall rank of the agent was calculated to two decimal points and the serial number as given in the table was decided based on its absolute value. It revealed that abiotic agents like wind, water stress (both excess and deficit) leads the table in term Forestry Bulletin, 12(1), 2012 Haryana 2 1 3 4 6 10 7 5 8 21 9 23 22 16 13 12 19 17 11 24 22 18 21 20 25 State Uttar Pradesh 1 2 3 4 6 5 8 7 9 10 11 12 14 17 13 18 15 16 19 20 21 22 23 24 25 Uttarakhand 2 1 6 3 4 9 5 12 7 8 15 14 11 13 18 10 17 20 16 19 22 21 23 24 25 Overall 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 of their potential to cause damage. During discussions with many of the growers, the identification of damages and causal agents for disease was extremely difficult for them and they tried to group them in order of their field observations than scientific terminology. The potential of some agents like bull is very high in Uttar Pradesh and Haryana, but very low in Punjab and little in Uttrakhand. Besides these agents poplar wood is also subjected to attack and degradation during storage in log yards and depots. This damage was restricted to some specific locations and factories and was included in the survey. 29 Fig. 1. Tree harvesting operation includes felling trees along with main root system. Fig. 2. A third rotation coppice variable growth of poplar trees retained on field boundaries along a roadside in Rudrapur, U.S. Nagar, Uttrakhand. Fig. 3. CAI and MAI curves for height (H), and diameter (D) at 8 years rotation. Fig. 4. Red arrows show movement of poplar wood to other states 30 Fig. 5. Peeling waste from veneer industry for pulpwood in the RIPC. ENVIS Conclusion Firmly established poplar culture with introduced germplasm of P. deltoides is a source of numerous goods and services at local, regional, national and global level. Poplar culture is largely in the private sector and immensely helping the country in mitigating chronicle shortage of wood raw material for domestic and industrial use. The unique success of establishing poplar culture on farm land with active participation of numerous growers is path breaking for initiating similar programmes under synergic partnerships between industry and farmers. Poplar is grown as a cash crop and providing remunerative returns to its growers, generating employment in rural areas, raw material for wood based industry, revenue through taxations for the state governments, increased tree cover to meet the objectives of the National Forest Policy 1988 and rehabilitation of river banks for their protection and averting soil erosion. With increasing demand for its wood, poplar culture is likely to expand within the RIPC and also to new locations in northeastern states along the Himalayan range for the benefit of the people and the country. References Agrawal, S.C. and Patil, B.D. 1956. Problem of fir (Abies pindrow, A. spectabilis) and spruce (Picea morinda) regeneration. Indian Forester, 82(7): 382-6. Burfal, B.S. 1999. Status of poplar in Uttar Pradesh. In: National Seminar on Poplar. Dehradun, 1999. Abstarcts. Dehradun, Forest Research Institute. pp.2-3. Chandra, J.P. 1986. Poplar-A cash crop for North Indian farmers. Indian Forester, 16(4): 316-320. Chaturvedi, A.N. 1982a. Poplar farming in U.P. U.P. Forest Bulletin, 45. Chaturvedi, A.N. 1982b. Poplar for farm forestry in Uttar Pradesh. Indian Forester, 107: 661-664. Chauhan, N.S. and Lakhanpal, T.N. 2000. Ecological and ethonobotanical studies on the flora of Spiti, Himachal Pradesh-A cold desert in the Western Himalaya. In: Kohli, R.K.; Singh, H.R.; Vij, S.P.; Dhir, K.K.; Batish, B.R. and Khurana, D.K.Eds. Man and Forests DNES, IUFRO, ISTS, PU. pp. 293-300. Chauhan, V.K. 2012. Personal communication. Dhanda, R.S. and Verma, R.K. 1995. Growth performance of Populus deltoides Bartr. in agroforestry plantations in Punjab. In: Khurana, D.K. Ed. Poplars in India: Recent research trends. Solan, IDRC-UHF. pp. 4156. Forestry Bulletin, 12(1), 2012 Dhillon, A.; Sangwan, V.; Malik, D.P. and Luhach, M.S. 2001. An economic analysis of poplar cultivation. Indian Forester, 127(1): 86-90. Dhiman, R.C. 2004. Availability of poplar wood-a boon for plywood industry. Plywood Gazette, 64-72. Dhiman, R.C. 2008a. Evolution of poplar based agroforestry in India. In: 23rd Session of International Poplar Commission, Beijing. [Available at: www.fao.org/.../ 16888 078c390e89188cd9928e0f38570fc8047.pdf]. Dhiman, R.C. 2008b. Employment generation through poplar farming and utilization. In: National Workshop on Role of Forestry in Employment Generation and Rural Development, Dehradun, 29-30 August 2006. Proceedings edited by S.S. Negi, R.K. Srivastava and Ombir Singh. Dehradun, FRI. pp. 95-104. Dhiman, R.C. 2009. Carbon footprint of planted poplar in India. ENVIS Forestry Bulletin, 9(2): 70-81. Dhiman, R.C. 2010a. Sacred trees of Himachal Pradesh. ENVIS Forestry Bulletin,10(2): 87-94. Dhiman, R.C. 2010b. Growing of poplar in Bihar: A hope for farmers and the wood based industry. Ply Gazette, 87-92. Dhiman, R.C. 2011. Wildlife damage to poplar. Indian Forester, 137(10):1212-1216. Dhiman, R.C. 2012. Diagnosis of intercrops in poplar based agroforestry in India. Indian Forester, 138(7): 600-609. Dhiman, R.C. and Gandhi, J.N. 2010. Innovations in nursery production for enhancing field performance and acceptability of poplar saplings. In: ScarasciaMugnozza, Giuseppe and Stanton, Brian J. Eds. Books of abstracts: Poplars and willows- from research models to multipurpose trees for a biobased society. IPS-V, Session 4: Innovative production systems for low input tree crops, Palazzo dei Congressi, Orvieto, 20-25 September 2010. pp. 113. [Available at: http://www.sisef.it/IPS-V/data/ material/IPS-V%20Book%20of%20Abstracts.pdf ] Dhiman, R.C. and Jagdish Chander. 2012. Expanding poplar culture and plywood industry. Plyworld, 29-31. Einspahr, D. W.; Peckham, J.R. and Benson, M.K. 1970. Fibre and pulp properties of triploid and triploid hybrid. TAPPI Journal, 53(19): 1853-1856. Fotidar, A.N. 1983. Some observations of poplar in Jammu and Kashmir State. Indian Forester, 109(10): 737-742. Gogate, M.G. and Deshpande, M.D. 1994. Poplar introduction in Maharashtra. In: National Workshop on Multipurpose Tree Species for Agroforestry in Maharashtra, Pune, 6-9 April 1994. Proceedings. Pune, BAIF Development Research Foundation. 31 ISFR (India. Ministry of Environment and Forests. Forest Survey of India). 2011. India state of forest report: 2011. Dehradun, The author. 286p. Jain, S.K. and Singh, Pramatma. 1999. Performance of intercrops in agroforestry system: The case of poplar (Populus deltoides) in Uttar Pradesh (India). Indian Forester, 125(2): 195-205. Jain, S.K. and Singh, Pramatma. 2000. Economical analysis of industrial agroforestry: Poplar (P. deltoides) in Uttar Pradesh (India). Agroforestry Systems, 49(3): 255273. Kiswan, Jagdish and Dinesh Kumar [n.d.]. Future of poplar in India. [Available at: www.fao.org/forestry/6285037bdb32f78ab8a552bf6b163f2ffc825.pdf ] Mathur, R.S. and Sharma, K.K. 1983. Poplars in India. Indian Forester, 109: 591-631. Milea, I. 1980. Correlations of interest for papermaking in the anatomical, physical and chemical characteristics of Salicaceae. Cellulose si Hirtie, 29(3): 103-104. Mishra, Alka; Swamy, S.L. and Puri, Sunil. 2004. Growth and productivity of soyabean under five promising clones of Populus deltoides in agrisilviculture system. Indian Journal of Agroforestry, 6(2): 9-13. NAEB (India. Ministry of Environment and Forests,National Afforestation and Eco-Development Board). 1993. Success story: Poplar for prosperity (A joint venture of farmers and industry). The author. Naithani, H.B. and Sumer Chandra. 1999. Diversity and conservation of indigenous poplars. In: National Seminar on Poplar, Dehradun, 25-27 November 1999. Abstracts. Dehradun, Forest Research Institute. p. 446. Negi, J.P.; Khosla, P.K.; Kaushal, P.S.; Shankhyan, H.P. and Singh, R.P. 1996. Eco-development impact and evaluation of desert development programme of cold 32 deserts of Spiti (1978-1993). Shimla, Himachal Pradesh. p.108. NPC (India. National Poplar Commission). 2012. India-Country report on poplars and willows. Dehradun, ICFRE. Puri, S.; Swamy, S.L. and Jaiswal, A.K. 2002. Evaluation of Populus deltoides clones under nursery, field and agrisilviculture system in sub-humid tropics of central India. New Forests, 23(1): 45-61. Rai, A.K. and Ilam Chand. 1988. Grease proof paper from poplar. Journal of the Timber Development Association of India, 34(4): 18-26. Sharma, K.K.; Dhiman, R.C. and Vakshasya, R.K. 1996. Variation in coppicing behavior of poplars. Van Vigyan, 34(3): 107-111. Singh, D.R.R. and Jhajaria, V.K. 2001. Evaluation of credit worthiness for institutional financing through growth of Populus deltoides Marsh grown in forest sites and farm forestry. Indian Forester, 127(12): 13111325. Singh, Kamla; Ram, P.O.; Singh, A.K. and Hussain, A. 1988. Poplar (Populus deltoides Bartram, ex. Marshall) in forest and agroforestry systems. Indian Forester, 115(11): 814-817. Singh, M.M.; Mathur, G.M.; Kalra, K.K. and Karira, B.G. 1981. Production of chemical, mechanical and semi-chemical pulps from clones of Populus deltoides. Indian Forester, 107(11): 725-733. Singh, S.V.; Rekha Bharati and Guha, S.R.D. 1982. Chemical composition of lignin and carbohydrates of Populus deltoides. Cellulose, Chemistry and Technology, 16: 421-429. WoP (Workshop on poplars, Haldwani, 23-24 January 1982). 1982. Proceedings. Dehradun, FRI and Colleges. 79p. WSD (WIMCO Ltd., Wimco Seedlings Division). 2011. Annual research report 2011. Rudrapur, WIMCO Ltd. z ENVIS Status of Poplar Breeding in India with Special Reference to Work Done at Dr. Y.S. Parmar University of Horticulture and Forestry D.K. Khurana Dr. Y.S. Parmar University of Horticulture and Forestry, Solan - 173 230 Introduction P Looking at the diverse plantation requirements and the species involved, different short and long-term strategies for their breeding and improvement were adopted at the university Forestry Bulletin, 12(1), 2012 oplars have become an important resource for the wood based industry in northern India since many industrial units are now dependant on it, as forest grown wood has almost become out of reach these industries. The ban imposed by the Supreme Court of India on green felling and efforts by various governmental agencies to increase the forest cover and reduce dependence on wood have made them look for alternative sources. Since the liking and dependence on wood cannot be separated from the mindset of the people, the only alternatives left are fast growing trees outside forests or farm grown woods. Amongst which poplars in India have become one of the important species. It’s a long way from the negligible dependence on poplar wood in 1970s to almost total dependence on poplar wood by 2012 most of plywood, ply-board industries and some pulp wood industries in northern India; that too in just a span of 40 odd years. The poplar growing is basically dependant on vegetative propagation where clonal propagules play an important role in plantations. Since vegetative propagules need to be upgraded sequentially on their loosing vigour and vitality, it is but imperative to have a breeding programme in place to deliver new and vigourous clones for plantations as the old clones become irrelevant over time. Whereas, most of the poplar growing countries with elaborate poplar plantation programmes, have some poplar breeding or clonal development programmes. Unfortunately in India, though poplar clones were imported time to time the well defined breeding programme for development of new and vigorous clones never existed at national level. For example, clones of poplars have been imported by the Forest Research Institute, Dehradun (Mathur and Sharma, 1983; Khurana et al., 1992; Tiwari, 1993; Chaturvedi and Rawat, 1994) with similar effort by the private industry, particularly WIMCO Ltd., in the early seventies (Dhiman, 2008). All the clones being planted were selected elsewhere with different climatic conditions, particularly photoperiod and latitudes, therefore, their responses were varied. In an effort to develop locally adapted clones to local climatic and photoperiodic conditions, a significant initiative was taken by the Dr. Y.S. Parmar University of Horticulture and Forestry in collaboration with the Canadian agency – International Development Research Centre of Canada (IDRC) during 1989-1995, by collecting 103 open pollinated families from the USA (Khurana and Narkhede, 1995). 33 Breeding Strategies Basically, the outline of the different breeding strategies adopted for the poplar improvement programmes are outlined in Fig. 1 conceived at the Dr. Y.S. Parmar University of 34 Horticulture and Forestry, Solan and also adopted at other institutes involved in the poplar improvement programmes in India. This followed somewhat similar strategies for both indigenous and exotic species for wood production with singular objective of wood production outside natural forests depending upon genetic resources. The foremost amongst them was the enrichment of the genetic resources. SELECTED PHENOTYPES NATURAL STAND (MASS SELECTION OR PLUS TREES) (TOP CROSS/POLYCROSS) FULL-SIB FAMILIES CLONAL PROVENANCE TRIAL HALF-SIB FAMILIES PROGENY TESTS BEST OF SELECTED TREES CLONED PROGENY TEST ) (200 – 300) 0 CL O N ES STECKLING SEED ORCHARD (2 03 The programme was designed to supply clones on a regular basis to the plantation agencies. Later on, the programme of clonal development was supported in the late 1990s by the World Bank Forestry Research, Education and Extension Project (FREE project) at the ICFRE. In India, most of the commercial poplar plantations are in the Gangetic plains and foothills of the Himalayas and constitute predominantly of exotic eastern cottonwood species (Populus deltoides ssp. deltoides). Whereas, the native species that are used as nurse crop for the silver-fir regeneration in high mountainous region, stabilization of hill slips and as a main source of timber in arid dry zone found only passing references till the improvement programmes on the native species, particularly the Himalayan poplar (P. ciliata) and white poplar (P. alba) were initiated by the Dr. Y.S. Parmar University of Horticulture and Forestry, Solan (Fotidar, 1983; Ramesh and Khurana, 2003, 2006, 2007). However, the productivity levels of clones of these various species vary according to site conditions and type of rooting ability and rooting behaviour. Clones have been categorized into five categories depending upon the plunging and anchor root behaviour, and thus dividing them into plantation categories (Khurana, 1994; Bhrot and Khurana, 2001). The productivity levels vary with various rooting categories, clones in question and site conditions from 15-30 m-3 ha-1 yr-1. Alternatively, the trees were found to be yielding wood at the rate of anywhere between 0.5 to 1 m3 per tree and the tonnage yield was also 0.5 to 1.0 t per tree. The productivity levels with Australian clones from Punjab and Haryana are reported to be much higher at 25 to 40 m-3 ha-1 yr-1 with some farmers reporting productivity levels of about 60 m-3 ha-1 yr-1 with intensive farming and supplementation of macro- and micro-nutrients under rigorous silvicultural practices (Dhanda and Verma, 1995; Kumar et al., 2004; Dhanda et al., 2008; Dhiman, 2008; Rizvi et al., 2011). The productive rotation age of eastern cottonwood ranged between 7-9 yrs in foothills, at higher elevations in Kullu Valley and Nauni (Solan) for P. deltoides and its hybrids it ranged from 9-15 yrs. The rotation cycle with P. ciliata and its hybrids was even higher at 15-25 yrs, again dependant on site, soil, moisture level and the clone planted. Looking at the diverse plantation requirements and the species involved, different short and long-term strategies for their breeding and improvement were adopted. BEST SELECTECD ORTETS CLONED CLONAL TESTS (200-300 CLONES) ARCHIVE PLANTATION FULL-SIB FAMILIESS PLANTATIONS MULTILOCATIONAL CLONAL TESTS PROGENY TESTS BEST OF SELECTED TREES --CLONED PLANTATIONS STECKLING SEED ORCHARD PLANTATIONS Fig. 1. Breeding strategy adopted for the improvement of poplars in India. Genetic Resources India is endowed with five native species and has a rich resource of other exotic species of poplars which have been brought into India since almost 15th century when Mughal first introduced P. nigra cv ‘Italica’ to the Kashmir Valley and other species (Fotidar, 1979) and clones introduced from Great Britain, Germany, Netherlands, Sweden, France, Italy, USA, and Australia, so that, India could become self-sufficient in the poplar wood requirements. However, disagreements over the species classification of poplars show no sign of abatement. The wide distribution of many poplar species, frequent introgressive hybridization (Broeck et al., 2005), a long history of cultivation and ease of vegetative propagation has led to much confusion in the nomenclature of poplars. Numerous synonyms exist, hybrids and cultivated varieties have often been named as species. Thus, species counts for ENVIS the genus range from the low 20s to over 80, depending on the authority. However, generally 30 species are well recognized of which six species, as given in Table 1, are represented in India with large number of species and Table 1. Species of Populus available in India S. no. Native species Exotic species Legitimate cultivar 1. P. euphratica P. nigra cv. Italica P. ‘Canescens’, P. 'Eugenei' 2. P. ciliata P. deltoides P. x euramericana cv. ‘I-214', ‘I-455’, ‘I-67’ ‘I-67/55’, ‘I-145’ 3. P. alba P. yunnanensis P. 'Lux', P. ‘Oxford’ 4. P. jaquemontiana var. glauca P. trichocarpa P. ‘Regenere’ 5. P. gamblei P. tremuloides P. 'Robusta' 6. P. suaveolens P. maximowiczii P. ‘Roxbury’ 7. P. simonii P. 'Serotina' 8. P. grandidentata More than 300 cultivars imported over the years cultivars being introduced from time to time as research initiatives. The studies in reproductive biology of P. ciliata also reveal the species to be dioecious with a single case of sexual dimorphism (Khurana, 1985). The female trees were more prevalent on relatively exposed sites and were much healthier compared to the male trees which were found to be in competition with surrounding population. Whereas, Chaturvedi and Rawat (1992) has listed various clones which are male or female on the basis of flowering at Lal Kuan, Kalika and Gaja. Normally, the clones of poplars do not flower at lower elevations of less than 1,000 m regularly. But they have been flowering at Lal Kuan nursery of the Uttar Pradesh State Forest Department off and on at an elevation of 256 m. Pollination in the species is normally by wind. In P. ciliata, it takes place 15 days after the floral bud break with a receptivity period of the female catkins being extended from 2 to 3 days (Khurana, 2000). Pollen size normally varies between 25-28 μ with larger pollen grains being observed in monoecious tree (31 μ). Unlike many other species of poplars, the pollen of P. ciliata has been difficult to store and looses its viability very rapidly (Dhir et al., 1982) thus, hampering long-term breeding programmes. Natural Genetic Variation The natural genetic variation in two indigenous species, P. ciliata and P. alba has been studied. P. ciliata was found to have a 3: 2 male female sex ratio ( Khosla et al., 1979) female trees had better growth rate (Khosla et al., 1980), edaphic conditions and water availability affected the overall growth of the trees and provenance variation with respect to growth, rust resistance (Sharma and Sharma, 2000), and infestation of the branches and leaves with galls was more (Chauhan and Khurana, 1992; Chaukiyal et al., 1995; Uniyal and Todaria, 2006). Reproductive Biology The reproductive biology of P. ciliata was analysed over a long period of time to look at its behaviour with respect to environment and stability of sex only one case of switching of sex was observed when a female tree turned monoecious (Khurana, 1985), otherwise trees showed consistency in their behaviour. Phenologically, the growth initiation and bud break is 2 to 3 weeks earlier at lower altitudes than higher altitudes. The average number of phenological growth period varied from 260 to 320 days, again with variation in altitudes, with most active growth period of 5 to 6 months. Species to species variation in phenological growth days was also found with maximum value being observed in P. yunnanensis compared to P. alba and P. ciliata (Mohanty and Khurana, 2000a and b). In P. ciliata flushing differences of one week with every 600 m elevation has also been found (Khurana and Mohanty, 2000). Forestry Bulletin, 12(1), 2012 Half-Sib Families Open pollinated seeds from 83 marked plus trees of P. ciliata were collected from the states of Jammu and Kashmir, Himachal Pradesh and Uttarakhand during different years (50 families during 1991 and 33 families during 1992) and after raising nurseries, the selections were made based on stem straightness, rust resistance and gall infestation of leaves (Khurana and Narkhede, 1995). Only one clone could be selected for rust resistance (Surkhigala-5) and one for leaf gall resistance (Chhatri-3), and 45 clones were selected for growth form. The best clone selected (Surkhigala-5) had almost three times more growth than of average clones. The open pollinated seed collections for P. deltoides Bartr. ex Marsh ssp. deltoides (Eastern cottonwood) from the USA have been many. Initially, the Y.S. Parmar University of Horticulture and Forestry, Solan with the help of the IDRC, and USDA Forest Service collected seed from 103 sources in the states of Texas, Lousiana and Mississippi (Farmer and Khurana, 1990; Khurana and Narkhede, 1995) which was raised in India at Parmar University and in China at Nanzing Forestry University. Based on their nursery performances, selections were made amongst clones akin to our photoperiodic and environmental conditions and at many places the plantations have also been raised from these indigenously selected clones (Chaturvedi and Rawat, 1992). After extensive and rigorous selection, 300 clones were selected from which 25 clones were used in the All-India 35 Co-ordinated trials under the FREE Project on poplars by the ICFRE (Rawat et al., 2001) and 100 clones were given to M/S Wimco Seedlings Ltd. for adaptive trials (Wimco Seedlings Ltd., 1997). Later, on open pollinated seeds from 104 candidate plus trees growing in 44 natural stands in the USA were brought by Singh et al. (2002) at the FRI, Dehradun from them 100 clones have been selected out for further trials (Kumar et al., 1999). The data on some of the earlier plantations have become available and 1st cycle of raised plantations has been harvested. There were significant differences among clones for height and diameter growth along with crown shape; i.e., crown width, leaf quality and photosynthesis rate. The average diameter of these clones ranged from 20 to 45 cm at Nalagarh, Paonta Sahib and Narainti, as is also evident from Fig. 2 (Khurana, 2007). Hybridization Natural hybrids in poplars is a common phenomenon, but ever since Moench in 1785 reported the hybrids between P. deltoides and P. nigra, intra- and inter-specific hybridization has been a prime research occupation amongst poplar geneticists. In India, intra-specific hybridization amongst best 40 clones of P. deltoides has been carried out and amongst these 289 clones from control-pollination and 111 clones from open-pollination have been selected at the FRI, Dehradun for field trials (Singh et al., 2002). The success of inter-clonal hybrids of P. deltoides has been more optimistic, which were labeled as Lal Kuan clones with L-series. These performed quite well under plantations at various places (Chaturvedi and Rawat, 1992, 1994), as well as some clones developed by M/S Wimco Seedlings Ltd. like ‘Udai’, ‘Kranti’ and ‘Bahar’. The inter-specific hybridization programme had problems while dealing with P. ciliata flowering branches. Unlike the flowering branches of P. deltoides which could be easily brought to the laboratory and stored and then at appropriate time could be raised by the twig-in-pot method for convenient breeding programmes, the flowering twigs of P. ciliata have to be grafted or buded on to the established stock for breeding purposes. Inter-specific hybridisation between P. ciliata, P. maximowiczii (three provenance collections), P. x euramericana ‘I-455’, P. deltoides, P. yunnanensis, and through hybrid embryo-rescue for P. ciliata x P. deltoides was carried out at Dr. Y.S. Parmar University Horticulture and Forestry, Solan (Khurana, 1989; Khosla and Thakur, 1991; Khurana and Thakur, 1995). The pollen for P. maximowiczii 36 was received from the Oji Paper Co., Japan and the pollen sources of P. yunnanensis and P. deltoides were earlier collections growing in the Populatum at Forest Nursery, Shilli (Solan). Jha and Kumar (2000) also raised inter-specific hybrids in different cultivars of P. deltoides, P. ciliata, P. yunnanensis and P. x euramericana ‘Robusta’, including reciprocals and backcross. Earlier, Chaturvedi and Rawat (1992, 1994) had also reported on the inter-planted open pollinated hybrids of P. ciliata and P. deltoides as well as on the inter-clonal hybrids of P. deltoides. While both Chaturvedi and Rawat (1992, 1994) and Jha and Kumar (2000) reported full compatibility between P. deltoides and P. ciliata and their reciprocals, Khurana and Bhanwara (1982) were able to show that only one way cross was possible between them. Embryo rescue by Khosla and Thakur (1991) was adopted to get the hybrid seedlings. Hybrid seedlings of P. deltoides ‘G-48’ x P. euphratica have also been produced to combine the rapid growth of P. deltoides and stress tolerance of P. euphratica (Singh et al., 2002). The most successful amongst inter-specific crosses have been between P. ciliata x P. maximowiczii (M-1016) and P. x euramericana ‘I-455’ x P. deltoides with very promising growth results in mid-hills (Khurana and Thakur, 1995; Khurana et al., 1995). The hybrid clones which have been selected for trials under various conditions based on their rooting pattern and behaviour are - CM-3183, CM-3108, CM-3254, CM-3120 and CM-3213 having categoryA type of rooting pattern with a dominant vertical sinker root at the base for interplanting conditions in agroforestry systems, clones CM-3226, CM-3246, CM-3122, CM-3239, CM-3195 and CM-3287 showing category B of root pattern and clones CM-3160, CM-3203, CM-3162 and Hyb-I showing category-C of root pattern for block planting (Khurana, 1994; Bhrot and Khurana, 2001). The clones Hyb-III, CM-3167 and CM-3130 with category-D type of root pattern have been selected for loose soil conditions. The rooting pattern of these hybrids was very strong as can be seen from a comparison of the rooting of hybrids, P. ciliata and P. deltoides ETP’s in Fig. 3. Hybrids of P. ciliata x maximowiczii were raised for the sites not amenable to either P. ciliata or falling outside its zone and where P. deltoides clones were found unsuitable. Initial growth differences in the nursery (32.60 N, 77.30 E) were reported to be greater by the parent at one site. Subsequently, these were planted at three sites: (i) Katrain (31.45 N, 77.30 E) representing river floodplain deposits, (ii) Palampur (32.60 N, 77.30 E) representing a tea garden with no irrigation, and (iii) Nauni (31.10 N, 77.20 E) representing a) seasonal water source, and b) dry fallow land. Growth differences were site specific, ENVIS Fig. 2. Productivity of selected clones from open pollinated families of P. deltoides. Fig. 3. Showing the rooting differences in the ETP’s of P. ciliata on the left, P. deltoides on the right and P. ciliata x maximowiczii in the centre which had stronger and more profuse secondary and tertiary roots. Fig. 4. Pattern of bark of the inter-specific hybrids of P. ciliata x maximowiczii. Fig. 5. Differences in the colour, shape, size and number of leaves at each node in the hybrids of P. ciliata x maximowiczii. and poor performance with diameter growth of less than 10 cm in 4 years was observed at site II. The growth at site I varied between 15 and 20 cm at 4 years, and the growth at site III-a ranged between 20 and 25 cm with a good height growth of about 20 m. After 20 years of growth, the average height of clones at Katrain was 25 m with diameter range of 40 to 50 cm, but at site III-a; i.e., Nauni (seasonal water source), though height was 20-25 m but the diameter growth ranged between 30 to 40 cm. The rooting was profuse in these hybrids in comparison to P. ciliata; the leaf size was double that of P. ciliata and four times than that of P. maximowiczii. Siblings showed a range of variation in branching pattern from the rosette shape of branching in P. maximowiczii to the simple alternate type in P. ciliata, and at maturity the bark pattern also varied from smooth to ribbed (Fig. 4 and 5). (P. maximowiczii) genotypes was carried out using the AFLP marker assay. Eight AFLP primer combinations detected 428 markers, of which 280 (66 per cent) were polymorphic. The phenetic dendrograms, as well as the PCO plots, separated the hybrids and the two parent species into three distinct clusters. The hybrids grouped closer to the P. ciliata (female parent) cluster as compared to the P. maximowiczii (male parent) cluster. The hybrid cluster contained internal groupings, which correlated to some extent with growth performance. The four best performing hybrids (42 M1, 65 M1, 23 M2, CM2-5-20/91) formed a distinct sub-cluster. Data from a single primer combination was sufficient for distinguishing the hybrids from the parents and assigning paternity. The hybrids showed 22 markers that were absent in P. ciliata but were monomorphically present in all the hybrids, suggesting outcrossing and common paternity. Further, these 22 markers were found in all the P. maximowiczii genotypes confirming it as the male parent (Chauhan et al., 2004). Molecular Characterization Genetic evaluation of 24 of these interspecific hybrids along with the two mother trees (P. ciliata), and five male-parent Forestry Bulletin, 12(1), 2012 37 Genetic diversity analysis with the help of AFLP was also performed on 43 of P. deltoides accessions introduced in India. Three other species, viz., P. ciliata, P. maximowiczii and P. euphratica genotypes were included as outgroups in the study for forming a long term breeding strategy. The AFLP successfully discriminated all the genotypes and outliers were distinguished very easily from the rest of the P. deltoides clones. The species P. euphratica was especially found to be very distinct from all the genotypes analyzed. All the ten AFLP primer combinations employed were found to be able to discriminate all the different clones. Statistical analysis indicated very high genetic similarity within the P. deltoides clones grown in India (0.775-0.978 similarity value). This was surprising considering they have been introduced/developed from different sources. Few of the clones, especially ‘65/27’, ‘PD345/183’, ‘C-181’ and ‘A-50 (89)’, were found to be very distinct among the P. deltoides clones and may actually be hybrids. The reason may be mislabelling/misidentification of the clones during their introduction or propagation or planting (Wilson, [n.d.]). The study showed that there should not be random mating of different clones, as is being done at present, but they must be first screened so that the situation of monoclonal plantations with very narrow genetic base could be avoided. References Bhrot, N.P. and Khurana, D.K. 2001. Variability studies for some root characters in different clones of poplar. Indian Journal of Forestry, 24(2): 150-152. Broeck, An Vanden; Villar, Marc; Van Bockstaele, Erik; Van Slycken, Jos. 2005. Natural hybridization between cultivated poplars and their wild relatives: Evidence and consequences for native poplar populations. Annals of Forest Science, 62(7): 601-613. Chaturvedi, A.N. and Rawat, B.S. 1992. Poplar tree improvement programme. In: 19th Session of the International Poplar Commission, Zaragoza, 22-25 September 1992. Proceedings. Vol. 1. Rome, FAO. pp. 505-513. Chaturvedi, A.N. and Rawat, B.S. 1994. Poplar tree improvement programme. Indian Forester, 120(2): 97-104. Chauhan, N.; Negi, M.S.; Sabharwal, V.; Khurana, D.K. and Lakshmikumaran, M. 2004. Screening inter-specific hybrids of Populus (P. ciliata × maximowiczii) using AFLP markers. Theoretical and Applied Genetics, 108(5): 951-957. Chauhan, P.S. and Khurana, D.K. 1992. Growth performance of different provenances of Himalayan poplar. In: 38 19th Session of the International Poplar Commission, Zaragoza, 22-25 September 1992. Proceedings. Vol. 1. Rome, FAO. pp. 687-693. Chaukiyal, S.P.; Mahtolia, D.C. and Singh, Ombir. 1995. Comparative performance of some provenances of Populus ciliata planted under nursery conditions. Advances in Forestry Research in India, 13: 35-44. Dhanda, R.S. and Verma, R.K. 1995. Growth performance of Populus deltoides Bartr. in agroforestry plantations in Punjab. In: Khurana, D.K. Ed. Poplars in India: Recent research trends. Solan, IDRC-UHF. pp. 4156. Dhanda, R.S.; Gill, R.I.S.; Singh, Baljit and Kaur, N. 2008. Agroforestry models for crop diversification in Punjab plains. Punjab, Department of Forests and Wildlife Preservation. 24p. Dhiman, R.C. 2008. Evolution of poplar based agroforestry in India. In: 23rd Session of the International Poplar Commission, Beijing, 26-30 October 2008. Proceedings. Rome, FAO. Dhir, K.K.; Charak, K.S.; Khurana, D.K. and Dua, I.S. 1982. Changes in the protein bands in pollen grains of Populus ciliata during storage and its effect on their viability and germination. Silvae Genetica, 31(1): 68. Farmer, R.E. and Khurana, D.K. 1990. Seed collection and storage of Populus deltoides. IDRC- Tree Improvement/Farm Forestry Network Newsletter, 2: 6-8. Fotidar, A.N. 1979. Some observations on poplars in Jammu and Kashmir state. In: Symposium on Silviculture, Management and Utilization of Poplars, Srinagar, 15-18 October 1979. Proceedings. Simla, The Manager Government of India Press. Fotidar, A.N. 1983. Some observations of poplars in Jammu and Kashmir state. Indian Forester, 109(10): 737742. Jha, K.K. and Kumar, Y. 2000. Interspecific hybridisation in poplars and initial performance of hybrids in tarai of Uttar Pradesh. Indian Journal of Forestry, 23(1): 111. Khosla, P.K. and Thakur, S. 1991. In ovule-embryo culture of immature embryos of Populus ciliata x P. deltoides. Phytomorphology, 41: 267-269. Khosla, P.K.; Kaushal, P.C. and Khurana, D.K. 1980. Studies in Populus ciliata Wall. ex Royle II. Phenotypic variation in natural stands. Silvae Genetica, 29(1): 31-37. Khurana, D.K. 1985. Sexual dimorphism in Populus ciliata Wall. ex Royle. Journal of Tree Sciences, 4: 57-60. ENVIS Khurana, D.K. 1989. Cross-ability patterns in Populus ciliata Wall. ex Royle. In: Meeting of IUFRO Working Party S2.02.10, Hann. Munden, 2-6 October 1989. Recent developments in poplar selection and propagation techniques: Proceedings. Hann. Munden, Institute of Forest Tree Breeding of the Hessian Forest Research Station and Research Institute of Fast Growing Tree Species. Khurana, D.K. 1994. Preliminary selection of poplar genotypes for agroforestry systems. In: Singh, Punjab; Pathak, P.S. and Roy, M.M. Eds. Agroforestry systems for degraded lands. Vol. 1. Jhansi, RMSI. pp. 279-285. Khurana, D.K. 2000. Reproductive biology of Populus ciliata Wall. ex Royle. In: Kohli, R.K. ; Singh, H.P.; Vij, S.P.; Dhir, K.K.; Batish, D.R. and Khurana, D.K. Man and forests. Chandigarh, Punjab University. pp. 235-240. Khurana, D.K. 2007. Genetic improvement of Populus in India: A case study. ENVIS Forestry Bulletin, 7(1): 59-67. Khurana, D.K. and Bhanwara, R.K. 1982. Ontogeny of catkin drop and embroyology of Populus ciliata and its crosses with P. deltoides. In: Khosla, P.K. Ed. Improvement of forest biomass. Solan, ISTS. pp. 413 418. Khurana, D.K. and Mohanty, T.L. 2000. Identification of selected clones of Populus deltoides Marsh. by qualitative morphological traits. Environment and Ecology, 18(4): 958-961. Khurana, D.K. and Narkhede, Satish. 1995. Poplar improvement in Himachal Pradesh (India). In: Khurana, D.K. Ed. Poplars in India: Recent research trends. Solan, IDRC-UHF. pp. 7-40. Khurana, D.K. and Thakur, Sanjeev. 1995. Populus ciliata x maximowiczii: Preliminary report on a potential hybrid for mid west Himalayan zone. Indian Forester, 121(9): 802-806. Khurana, D.K.; Chauhan, S.K. and Mehta, Arun. 1992. Genotype and site interaction studies in some promising clones of exotic poplars in Himachal Pradesh. Journal of Tree Sciences, 11(2): 112 124. Kumar, D.; Singh, N.B.; Rawat, G.S.; Srivastava, S.K. and Mohan, D. 1999. Improvement of Populus deltoides Bartr. ex Marsh in India - I. Present status. Indian Forester, 125(3): 245-263. Kumar, R.; Gupta, P.K. and Gulati, A. 2004. Viable agroforestry models and their economics in Yamunanagar district of Haryana and Haridwar district of Uttaranchal. Indian Forester, 130(2): 131-148. Forestry Bulletin, 12(1), 2012 Mathur, R.S. and Sharma, K.K. 1983. Poplars in India. Indian Forester, 109(9): 591-631. Mohanty, T.L. and Khurana, D.K. 2000a. Comparative growth performance of Populus ciliata, P. yunnanensis, P. alba, P. deltoides, hybrid of P. ciliata and hybrid of P. deltoides in nursery stage. Environment and Ecology, 18(2): 392-397. Mohanty, T.L. and Khurana, D.K. 2000b. Morphological characterization of selected clones of P. deltoides Marsh. Environment and Ecology, 18(4): 948-951. Ramesh, K.R. and Khurana, D.K. 2003. Natural provenance variation in P. alba Linn. from western Himalaya. Indian Forester, 129(9): 1077-1084. Ramesh, K.R. and Khurana, D.K. 2006. Rooting behaviour studies in P. alba provenances for different agroforestry needs. Indian Forester, 132(8): 989-1000. Ramesh, K.R. and Khurana, D.K. 2007. Standardization of vegetative propagation techniques in P. alba Linn. cuttings. Indian Forester, 133(4): 464-474. Rawat, G.S.; Singh, N.B.; Gupta, R.K.; Singh, K. and Sharma, S.D. 2001. Clonal evaluation of poplar (P. deltoides Bartr.) in Eastern Uttar Pradesh I – Nursery testing. Indian Forester, 127(1): 70-80. Rizvi, R.H.; Dhyani, S.K.; Yadav, R.S. and Singh, Ramesh. 2011. Biomass production and carbon stock of poplar agroforestry systems in Yamunanagar and Saharanpur districts of northwestern India. Current Science, 100(5): 736-742. Sharma, R.C. and Sharma, Sanjeev. 2000. Status and distribution of foliar diseases of poplar in Himachal Pradesh. Indian Phytopathology, 53: 57-60. Singh, N.B.; Kumar, D.; Gupta, R.; Pundir, I. and Tomar, A. 2002. Intraspecific and interspecific hybridization in poplar for production of new clones. ENVIS Forestry Bulletin, 2(2): 11-16. Tiwari, D.N. 1993. Poplar. Dehradun, Surya Publications. 321p. Uniyal, A.K. and Todaria, N.P. 2006. Provenance-progeny trial for domestication of P. ciliata clones. Journal of Tropical Forest Science, 18(4): 269-273. Wilson, N. [n.d]. Genome analysis of Populus species: Assessment of genetic diversity of P. deltoides, characterization of wide hybrids and phylogenetic analysis using molecular markers. [Available at: www.teriuniversity.ac.in/files/ neeti_wilson_20100707134719.pdf]. Wimco Seedlings Ltd. 1997. Annual research report. Rudrapur, Wimco Seedlings Ltd. z 39 Clonal Development and Diversity in WIMCO’s Poplar Programme R.C. Dhiman and J.N. Gandhi WIMCO Ltd., Wimco Seedlings Division, Rudrapur - 263 153 Introduction W WIMCO is employing a simple and realistic but exhaustive screening process for clone development in poplar and a few other tree species. In case of poplar, seed obtained from manipulated crosses and selected half-sib parents are germinated 40 IMCO - a safety match company with one of its factory located in Bareilly, Uttar Pradesh (U.P.) started working on poplars during 1970s to develop it as match wood plantation tree on farm land in North India. Field performance of WIMCO’s introduced two poplar (Populus deltoides) clones, viz., G48 and G3 in 1969 from Australia (Chaturvedi, 1982) paved the way for its culture on farm land in the country. Fast growth of these clones impressed the management of the company to initiate a planned programme for promoting its plantations for matchwood production. Swedish Match, the parent company of WIMCO in those days, had keen interest in poplar and aspen plantations to support its match business in many countries. The promotion of poplar plantations in India was an extension of the company’s commitment to develop matchwood resources with backward linkages to ensure sustained wood raw material production and availability. WIMCO created an Agroforestry Extension Division in 1976 with a strong team of field extension workers and a research facility in 1982 which later on was upgraded into an independent company – Wimco Seedlings Ltd. in 1984 for the focused research on poplar and a few other socially and industrially important tree species. Wimco Seedlings Ltd. was merged with WIMCO Ltd. in 2005 and is operating as one of its division since then. However, these organisational changes did not have any effect on its research and development activities including poplar improvement which maintained constant continuity till date. Clonal Development Programme WIMCO is employing a simple and realistic but exhaustive screening process for clone development in poplar and a few other tree species. In case of poplar, seed obtained from manipulated crosses and selected half-sib parents are germinated (Fig. 1) and the new populations are followed for 18-20 yrs; i.e., 3-4 yrs in nurseries, 8 years in local level and remaining period in multi-location trials for screening desired individuals. Poplar improvement is presently based on P. deltoides whose clones are well adapted throughout the region of intensive poplar culture (RIPC) (Dhiman, 2012), where none of the indigenous species have ever thrived before their introduction. The initial programme was restricted to screening of ENVIS seedling populations obtained from half-sib parents on noticing first time seeding on G48 clone in 1982 and later on, manipulated crosses were started among the available clones of P. deltoides w.e.f. 1989. Inter species crosses are now being made for over a decade period and their progenies are followed for favourable characters related to growth, form and resistance to diseases and insects. Most of the seedlings raised from crosses of P. deltoides with P. ciliata, P. sauveolens and P. nigra failed to tolerate the hot and dry weather conditions those exist in the RIPC. Some hybrids developed between P. ciliata and P. sauveolens; and P. nigra and P. sauveolens are neither well adapted nor productive in these locations. Some of these are maintained to attain reproductive phase for making backcrosses. During 2008-9, some seed were produced from crosses made between P. gamblei and P. deltoides, by manipulating delay in reproductive bud break in P. gamblei. Some seed and seedlings were also produced from the crosses between P. gamblei and P. ciliata and they also failed to survive warm and humid weather conditions in our operational area in plains. Nursery Screening Poplar program in the company employs traditional methods and materials to develop new clones. Each year, shoots with reproductive buds collected from trees of selected parents are cleft grafted on root stock already established in open nursery beds. Pollen collected from the identified parents is used for making crosses. Flowering shoots are covered with the muslin cloth bags during flowering and pollination. Capsules develop and expand quickly after fertilization. Mature capsules are collected during late April, May and June; seed on separation from the cotton is immediately sown in very light soil media. Seed germinate in two days period of sowing. Seedlings at 2-4 leaf stage are shifted in the cavities (root trainers). Seedlings are screened for disease and pest resistance in the first year itself. Selected seedlings are, then, planted in the nursery beds during the following February and are followed for further screening for diseases and insects resistance and form (Table 1). At the end of the growing period only the selected individuals are multiplied in good number in next year nurseries for field trials in the following years when they are planted in 2-3 sites for local level field trials. Newly developed seedlings are also sometimes placed under the saplings of susceptible clones or sprayed with the water suspension of Bipolaris spp. fungus causing leaf blight. Field trials are monitored for a full rotation of 8 years when the selections of desired individuals is made. Selected trees are rejuvenated by serial propagation, clubbed with selections of some of those from preceding or following years and are grown and monitored in the multi-location trials in the entire RIPC. Selected individuals based on the performance in multilocation trials are rejuvenated and produced in commercial nursery for supply of saplings to the growers. Each year a new trial is added in the system as per the procedure outlined above. The actual multiphase screening of each population is illustrated with data in the following pages. An exhaustive multiphase screening process is followed for 18-20 years to make selection of suitable individuals from nursery and field trials. A major screening is carried out in the newly produced population on completion of first year growth in the nursery beds (2nd year from seedling production from seed). Some screening is already carried out during the first year when the seedlings are maintained in the cavities from their shifting from germination trays. Some individuals are also screened during the third and/or fourth year in nurseries when only the selected ones are moved for local level field trials. The screening percentage is quite high in the nursery stage itself. For example, the screening percentage carried forward after 1st, 2nd, 3rd and 4th screening were 80.11 per cent, 70.80 per cent 1.05 per cent, 1.05 per cent, and 0.12 per cent respectively, of the original population of year 2000 population (Table 1). A liberal screening process is followed in case of populations produced from the manipulated crosses made between different species (Table 2). This is with the simple intention that most of the commercially grown clones still belong to introduced P. deltoides origin. The need is felt that if some of the crosses with other species especially with indigenous poplars are found suitable for commercial production or for back crosses, then it could significantly help in broadening the limited genetic base. P. gamblei is an Table 1. Multistage screening of full and half-sib population (year 2000) in the nursery Pop ulation H alf-sib Full-sib Total Selection (% ) R ejection (% ) Seedling prod uced 21,512 489 22,001 N ursery screening (after yr) 1 st 2 nd 3 rd 17,220 406 17,626 80.11 19.89 15,315 261 15,576 70.80 29.20 129 103 232 1.05 98.95 Forestry Bulletin, 12(1), 2012 4 th (Final; local level field testing) 128 102 230 1.05 98.95 5 th (for multi-loca tion field trials) 19 7 26 0.12 99.88 41 Table 2. Multistage screening of full and half-sib population (year 2009) in the nursery S. no. P a rent S e e d lin g p rod u ced N u r s e r y sc r e e n in g (a f te r y r ) 1 1. G -4 8 X G -3 2. W S L -3 9 X G -3 3. 2 nd 3 rd 4 t h (F in a l) 40 16 7 1 1 120 66 52 3 2 W S L -3 9 X W S L - A /2 6 90 51 32 4 2 4. W S L -3 9 X P . c ilia ta 10 8 8 0 0 5. S 7 C 8 X G -3 160 90 90 15 15 6. S 7 C 8 X W S L - A /2 6 330 233 191 20 20 7. S7C 8 X S7C 15 160 136 136 9 15 8. 9. S 7 C 8 X P . c ilia ta W S L -3 2 X G -3 240 80 202 10 194 46 7 12 5 11 10. W S L -3 2 X S 7 C 4 16 52 10 3 3 11. 12. W im c o -1 1 0 X G -3 W im c o -1 1 0 X W S L - A /2 6 28 200 11 21 20 170 13 36 13 34 13. W im c o -1 1 0 X P . c ilia ta 38 175 21 1 1 14. W im c o -6 2 X P . c ilia ta 15 22 10 0 0 15. P . tr ic o c a rp a X P . c ilia ta 96 66 35 0 0 16. P . c ilia ta X G -3 12 8 8 0 0 1635 1167 7 1 .3 8 1030 6 3 .0 0 124 7 .5 8 116 7 .0 9 2 8 .6 2 3 7 .0 0 9 2 .4 2 9 2 .9 1 T o ta l S e le c tio n (% ) R e je c tio n (% ) ideal but difficult material to handle in this regard. It has fast growth and adapted to low latitudinal locations in subtropical conditions. The species differs in rooting ability, flowering period and duration from most other introduced and indigenous species. A very early flowering in P. gamblei during late December relative to very late in March-April in all other indigenous and introduced species grown in the RIPC has critically affected breeding programmes with this species. Further flowering period in P. gamblei at Rudrapur, Uttarakhand is restricted to around one week period compared to its staggered period for around 1.5 months in case of P. deltoides grown under different altitudinal locations. In 2009, full and half-sib population with crosses made between P. deltoides, P. ciliata and P. tricocarpa, 71.38 per cent, 63.0 per cent, 7.58 per cent and 7.09 per cent after 1st, 2nd, 3rd and 4th screening respectively of the original population was retained for the local level trial. Screening at Local Level Field Trials The second phase screening is carried out in the local level field trials. Individuals selected from the nursery screening are multiplied in adequate number and planted in 2-3 sites on the company’s farms or in some farmers’ field near our operational area. The individual tried in these trials are many and well replicated single tree plots with increased replications are established inside the normally grown poplar plantations to avoid the boundary and side effects. Data is mainly recorded for growth and form and the 42 st selection is made at the end of the rotation mostly at 8 years on company’s farms and for varying rotation on farmers’ land. An example of such trial with selected individuals from multiple trials is given in Table 3. The individuals from such trials are selected based on a composite growth index of height and DBH+2SD. Screening at Multilocational Field Trials Third phase screening is carried out in the multi-location trials which are conducted simultaneously throughout the RIPC or, sometimes, in certain isolated locations in view of specific objectives associated with that site. Presently, three multilocation trials established in the Region of Intensive Poplar Culture (RIPC) during 2002, 2003 and 2007 on 12, 16 and 40 sites, respectively are being monitored. The overall ranking of the clones during different years and sites in 2002 trial is given in Table 4. The data in the Table indicate a variable harvesting time by the growers based on their financial needs. These trials are planted inside the normal plantations made on farmers’ fields and, therefore, farmers start harvesting them as per their convenience. The data in the table indicate that the harvesting of the trial plantations was started from 4th years by one grower, by one more in 5th year, one in 6th year, three in 7th year and four in 8th year. Two of the plantations which are still maintained have been planted in the forest, are still growing and are likely to be harvested at 12 years of rotation age followed for such plantations. Overall ranking of the tested clones in these trials based on height and diameter growth clearly indicates a ENVIS Table 3. Performance of 25 clones in a local area trial at Chandain Farm, Bilaspur, Uttar Pradesh Clone Initial Height DBH (m) (cm) Growth at 96 months (8 yrs) Height (m) DBH (cm) MEAN (SD) CV% MEAN (SD) CV% Wimco-81 4.4 2.8 27.2(2.25) 08 Wimco-98 4.6 2.7 25.5(2.16) 08 28.8(3.47) 12 27.5(4.06) 15 Wimco-A/26 4.4 2.5 25.4(1.05) 04 24.9(1.97) 08 Wimco-85 4.5 2.6 24.9(2.08) 08 24.5(2.93) 12 Wimco-84 4.6 2.7 25.7(1.29) 05 24.4(2.14) 09 UDAI 4.2 2.3 24.9(1.88) 07 24.2(1.79) 07 Wimco-91 4.4 2.9 24.5(1.73) 07 23.9(1.98) 08 Wimco-82 3.6 1.9 23.9(0.49) 02 23.8(0.21) 01 Wimco-A/49 4.2 2.6 24.4(1.11) 04 23.5(1.75) 07 Wimco-103 4.0 2.4 23.9(1.05) 04 22.9(0.67) 03 Wimco-90 4.0 2.5 24.6(0.95) 04 22.9(1.72) 07 Wimco-94 3.9 2.4 23.3(1.71) 07 22.5(2.58) 11 Wimco-14/2 4.2 2.2 23.2(1.09) 05 22.4(1.31) 06 Wimco-88 4.4 2.6 23.6(2.50) 10 22.4(2.88) 13 Wimco-99 3.9 2.3 22.5(0.84) 04 22.2(1.22) 05 Wimco-96 3.9 2.2 23.4(1.66) 04 21.6(2.42) 11 Wimco-97 4.4 2.6 23.3(0.53) 02 21.4(0.39) 02 Wimco-102 3.6 2.1 22.6(1.54) 07 21.1(2.30) 11 Wimco-101 3.7 2.3 22.3(3.19) 14 21.0(4.62) 22 Wimco-6/24 4.5 2.5 21.8(1.35) 06 20.4(1.10) 05 Wimco-86 Wimco-87 4.8 3.9 2.5 2.3 22.3(0.82) 04 21.9(1.65) 07 19.9(0.74) 04 19.9(1.84) 09 Wimco-92 4.2 2.4 21.7(2.22) 10 19.0(2.68) 14 Wimco-89 3.7 2.2 21.3(1.57) 07 18.6(1.99) 11 Mean 4.1 2.4 23.7(1.44) 06 22.7(2.35) 10 SE Diff. 1.24 1.77 CD (0.05) 2.43 3.47 consistency for two clones, viz., Wimco 81 and Wimco 83 till 6th year of growth. The two remaining sites have produced trees of less height and DBH with very low management inputs which also indicates that appropriate cultural operations are necessary for exhibiting the actual potential of clones on tested sites. In addition to above, the screening of clones is also done for specific objectives like against red mite which is common in eastern locations due to warm and dry weather conditions (Dhiman, 2007). Wood testing for end use is also an isolated trial conducted in specific poplar based units (Dhiman and Gandhi, 2006). From these trials, two clones Wimco 81 and Wimco 83 were selected based on six years performance, rejuvenated and multiplied for commercial production and for supply of the saplings to the growers. We prefer to monitor our clonal trials to full rotation of 6-8 years, though, some recommendations are available for early selection for fast mass multiplication of leading clones (Kumar and Singh, 2001). We also believe in conducting repeated clonal trials to avoid loss to growers from premature testing and release of new clones. Numerous growers have already had a very bad experience of growing tissue cultured poplar which repeatedly performed very poor (Dhiman and Gandhi, 2010). The company includes selected clones from these trials in its germplasm and regularly updates and monitors them for various characters. The germplasm is maintained in the nursery by replanting five to 10 cuttings each year and also as a field plantation in one to two sites on company’s Table 4. Ranking of clones in 2002 multi-location trial on12 trial sites 1st position among the tested sites Ranking among the tested clones Clone Nry 1 2 3 4 5 6 7 8 Nry 1 2 3 4 Wimco-27 V VI V III Wimco-28 VII II II II V II IX II VII V Wimco-38 XI VIII VIII V III V Wimco-39 VI IV IV III III Wimco-80 III VII VI VIII Wimco-81 IV IX IX Wimco-82 XII XI Wimco-83 VII I Wimco-84 IX Wimco-A/26 VII V 2 - 1 - - IV IV - - - - - VII VII VII - 1 - - 2 IV IV III VI 2 1 - - VIII VIII III II III 1 2 - VIII VI III II VI VII 1 - 1 XII XII VII XII VII X X - - 1 - - - - - - I I I I I I I - 5 6 6 7 2 3 1 1 XII X X XI X XI XI XI - - 1 2 - 1 - - - X X X XI X XI X IX IX - 1 - - - - - - - Wimco-A/49 II III III VI VII VI VI XII XII 4 1 - - - 1 - 1 - G-48 I V VII VII IV IX VIII VIII II Site (no.) Forestry Bulletin, 12(1), 2012 5 6 7 8 - - - - 1 1 - - 2 1 1 - 1 - - 2 1 - - - - - - - 1 2 4 1 - 2 1 2 4 - 1 - - - 12 12 12 12 11 10 9 6 2 43 A Case Study of 1997 Full-Sib and Half-Sib Population Ninteen thousand one hundred ninty five seedlings were produced from manipulated crosses involving 9 female clones (G48, Wimco 62, St121, 3201, S7C13, S7C8) and 6 male clones (St3, St63, S7C3, S7C4, S7C20, 112910) of P. deltoides in 39 attempts made between 17-2-1997 to 26-3-1997. There were 36 unsuccessful attempts of making crosses between 22nd February to 26 March, 1997 with some female clone’s mainly; St12, St75 and L34 and some male clones. One lakh thirty six thousand seven hundred forty two seedlings were also grown from the seed collected from open pollinated G48 (117577 number seedlings) and S7C13 (19195 seedlings) parents. During nursery screening (4 time screening) in three years, 41.39 per cent, 0.16 per cent, 0.16 per cent and 0.04 per cent individuals were selected after the screening process for overall disease rating (scale 0-4) against fungal pathogens viz., Phoma spp., Bipolaris spp., Cercospora spp.), and stem straightness (scale 0-4). Fifty four individuals from this population were selected and planted in two local level field trials in Uttarakhand. The trials were monitored for growth, form and reproductive behaviour for full rotation; i.e., 8 years. A female individual flowered in third year, 29 individuals (53.7 per cent) by 5th year, 35 (64.8 per cent) by 6th year and 53 (98.1 per cent) by 7th year. Out of the total of 53 individuals attaining reproductive age by 7th year, 30 (58.5 per cent) were male and 23(41.5 per cent) were female. Individual number 86 was leading performer producing 1.438 m3 timber volume (down to 30 cm mid girth merchantable log thickness) with 30.8 m height and 41.5 cm DBH at 8 years rotation. Nine individuals were selected out of this trial for multi-location trial which was established on 40 sites across the entire RIPC. Three individuals now named as WIMCO 108, WIMCO 109 and WIMCO 110 have been selected based on overall performance in multi-location trials for the commercial production. These clones were also screened for red mite infestation which is very common in warm locations towards eastern limits of RIPC. WIMCO 110 (earlier coded as individual No. 163) has been found highly resistant to red mite infestation (Dhiman, 2007). These three clones are now commercially produced and being supplied to the growers. Fig. 1. Hybridization work followed at WIMCO. 44 ENVIS farm. We closely and regularly monitor the clones numbering 492 maintained in germpalsm, out of which 344 were included from our own poplar improvement programme, 57 procured from UHF, 15 from Uttarakhand Forest Department and 76 exotic clones introduced at different periods. These clones exhibit wide variation in growth, form and their response to diseases and insect attack. For example, the nursery performance of these clones during the year 2011-12 indicates three clones with a height: DBH ratio of 125-150, six with 151175 ratio, 93 with 176-200 ratio, 228 with 201-225 ratio, 149 with 226-250 ratio and 13 with more than 250 ratio at one year seedling production phase. These clones are also regularly monitored for disease resistance every year. The ranking index (Kotle, 1985) for diseases for all these clones is given in the Table 5. Leaf blight caused by Bipolaris spp. is a serious disease and is rigorously monitored in our tree improvement programme. Most of the clones in our tree improvement programme are screened out against its infection and, therefore, it includes only a few susceptible clones for this fungus. Blistering and Sclerotium leaf spots are posing new threat and these have now been included for screening in the poplar improvement programme. Phoma leaf spots are now recorded widespread towards the fag end of the growing season when most of the lower leaves start dropping prematurely. Blistering is developing as a potential damaging disease wherein some mortality of field planted saplings is carried forward from the infected nurseries. It now finds equally good space in poplar improvement programme. Other diseases are though noticed widespread but their damage on the existing clones has not been found very serious and is being monitored for maintaining the history of disease in reference to clones. Phoma leaf spot is also on the watch list in the improvement programme. Clonal Diversity Numerous poplar species, hybrids and clones have been introduced in India from various countries during the last 60 years. Out of these, clones of P. deltoides developed from its low latitudinal populations have proved successful in the country. Clones presently that find mention in India belong to many series, viz., WSL, Wimco, G, L, EL, D, St, S, I, IC, FRIAM, FRIFS, PL, Pant, UFC, UCM, UD, and even simple named and numbered series (D series clones are also mentioned as St series in some publications). G, St, D, S, I and IC are introduced series clones and the remaining are indigenously developed ones. Many clones especially picked up from WIMCO are used in research trials before their final release and are quoted by their original numbers. WSL, Wimco and named series like Udai, Kranti and Bahar clones have been released by WIMCO and many of these are widely grown and preferred clones throughout the RIPC. The next preferred series of poplar clones is S series which were introduced from the USA. Numerous clones under this series were tested across the RIPC and two widely grown ones are S7C15 and S7C8. The former is widely grown throughout RIPC, whereas, S7C8 finds preference with growers in UP and UK states. L and EL series clones are from Uttar Pradesh (UP) Forest Department; FRIAM and FRIFS from the Forest Research Institute (FRI), Dehradun; PL from Punjab Agriculture University, Ludhiana, Punjab; Pant series from G.B. Pant University of Agriculture and Technology, Uttarakhand; and UFC, UCM, and UD series clones from the University of Horticulture and Forestry Solan, Himachal Pradesh. Performance of introduced G3 and G48 clones laid down the base for the poplar culture in plain areas in India. G3 was the main clone till mid 1990’s whereas G48 became widely preferred clone thereafter. Some space created by the exit of G3 on developing susceptibility to leaf blight, was quickly occupied by Udai clone. Of late, the share of G48 in field plantations is decreasing on developing susceptibility to many pathogens and insects. Besides, there are now many other equally good indigenously developed clones, some of which have both wide scale and endemic acceptability. Some L series clones especially L34, L13 and L49 were also grown in some locations during some period. Saplings of L34 clone produced from tissue culture originated mother plants were also supplied in large number across the RIPC and their performance was Table 5. Annual screening (2011-12) of germplasm clones for major diseases Infection (%) Blistering No infection 0-20 21-40 41-60 61-80 81-100 Total 281 52 54 36 37 32 492 Sclerotium leaf spots 488 3 0 1 0 0 492 Forestry Bulletin, 12(1), 2012 No. of plant infected with disease Phoma leaf Cercospora leaf Aletrnaria leaf spots spots spots 1 47 291 1 39 80 3 38 64 10 57 32 35 94 18 442 217 7 492 492 492 Bipolaris leaf blight 486 3 1 0 0 2 492 45 subnormal compared to the traditionally propagated saplings from stem cuttings (Dhiman and Gandhi, 2010). Clones which were introduced in the initial phase of poplar planting or field trials, viz., P. deltoides ‘IC’, I, D series and even 65/27 are still spotted in some field locations and are grown by some private nurseries ignorantly or even may be regenerating from root suckers. The present nomenclature of poplar clones creates a lot of confusion and the use of different names for the same clones by different organization is also not ruled out. WIMCO raised first ever poplar nursery outside government sector with its introduced G48 and G3 clones at Bareilly, U.P. during 1969. A few saplings out of this production were planted on farmers fields around Bareilly during the following years. The early performance of these saplings on farmer’s fields boosted the confidence of the management of the company to initiate a planned programme for poplar culture on farm land. U.P. Forest Department was already conducting trials on forest land with the introduced clones of P. deltoides, viz., I-488, I-214, I-215 and I-15-II initially (1965-1968) and then with ‘IC’, St121, G3 and G48 clones (Chaturvedi, 1982). The department introduced G3 clone in its programme in 1972 and G48 in 1975. A total of 1,355 hectare forest area in U.P. was planted with 29 poplar clones till 1981, of which the maximum 35.21 per cent area was with clone ‘IC’ followed by 21.80 per cent with G3, 8.62 per cent with D121, 6.64 per cent with D124 clone and remaining with others. The share of G48 was only 3.36 per cent during this period (Chaturvedi, 1982). WIMCO also supplied saplings of St121, and ‘IC’ clones initially to the growers in the states of Punjab, Haryana, U.P. and elsewhere under its regular extension programme w.e.f. 1976. The share of St and ‘IC’ series clones sharply declined and G3 and G48 clones developed preference among the growers. During 1990’s clone G3 constituted more than 90 per cent planting stock in many locations including in Yamunanagar district of Haryana which is the main poplar wood trading centre in the country. Clones G-3, St-100, St121, L-34, etc. have now some isolated presence but are not recommended for plantations in greater part of RIPC because of low productivity, threat of insect and disease infestations to these clones. Presently, around two dozen clones are commercially grown in the country. WIMCO this year (2012) is growing approximately 6.5 million saplings in around 40 nurseries throughout the RIPC. These will be supplied to the growers and a few thousands of them would be used for planting in its own farms and multiplication. Share of different clones in the company’s poplar programme implemented throughout the major part of its growing region in the country especially in the RIPC (between and within states, Table 6) indicates a complex matrix of their acceptability. Company’s developed and introduced clones including clone G48 are still the leading clones demanded by the growers. G48 followed by WSL 22, Udai, WSL 39, S7C15, Wimco 81, WSL 32, S7C8, Kranti, Wimco 108, WSL A/26, WSL A/49 and around a dozen others are grown by the company. Clones G48, WSL 22, Udai, WSL 39 and WSL 32, Wimco 81and S7C15 together constitute over 90 per cent of the total planted poplar in the country. Out of 6 recently released clones, viz., Wimco 81, Wimco 83, Wimco 108 and Wimco 110 are now being demanded by the progressive farmers. Some clones like L34 developed by Uttar Pradesh Forest Department and introduced S7C4, St 121 also demanded by a very few growers and are grown and supplied Table 6. Share of clones in sapling production between and within states in WIMCO’s poplar programme (2012) C lone G-48 U dai S7C8 S7C15 W S L 22 W S L 32 W S L 39 W S L A/49 W S L A/26 Kranti B ahar W im co-81 W im co-108 W im co-110 G-3 W im co-83 W im co-109 O thers T otal C lone UP 19.41 43.49 75.55 85.13 41.01 34.32 39.60 87.87 0.00 50.92 98.03 25.05 14.39 45.13 100.00 4.76 0.00 21.02 35.18 share (% ) am ong states UK Pb 37.31 32.87 15.51 19.06 14.18 1.65 2.97 10.35 24.08 20.44 42.85 2.61 40.61 12.72 12.13 0.00 31.04 52.33 4.24 4.22 1.97 0.00 41.39 16.95 9.56 30.71 12.90 22.37 0.00 0.00 33.63 37.77 9.40 51.43 78.98 0.00 28.65 22.64 H RY 10.41 21.93 8.63 1.55 14.47 20.22 7.07 0.00 16.58 40.63 0.00 16.61 45.34 19.59 0.00 23.84 39.17 0.00 13.52 UP 19.98 14.71 3.97 13.93 21.87 2.85 10.19 2.61 0.00 2.31 1.42 3.80 0.56 1.15 0.48 0.09 0.00 0.09 100.00 C lone share (% ) w ithin states UK Pb HRY 47.18 52.58 27.89 6.44 10.02 19.30 0.91 0.13 1.18 0.60 2.63 0.66 15.77 16.94 20.07 4.36 0.34 4.36 12.83 5.08 4.73 0.44 0.00 0.00 1.16 2.47 1.31 0.24 0.30 4.79 0.04 0.00 0.00 7.71 4.00 6.56 0.46 1.85 4.57 0.40 0.88 1.30 0.00 0.00 0.00 0.82 1.16 1.23 0.23 1.62 2.06 0.42 0.00 0.00 100.00 100.00 100.00 T otal 36.22 11.90 1.85 5.76 18.76 2.92 9.05 1.04 1.07 1.59 0.51 5.34 1.36 0.90 0.17 0.70 0.71 0.15 100.00 UP=Uttar Pradesh, UK=Uttarakhand, Pb=Punjab and HRY=Haryana 46 ENVIS to them on their demand. Data on location-wise clonal production and supply from so many field sites is difficult to accommodate in this paper. The data in the Table 6, however, clearly indicates wide spread and endemic acceptability of many clones. Whereas, G48, WSL22, WSL39 have widespread acceptability, many others are restricted to a few locations. Clone G3, once a dominate clone in poplar culture over the greater part of the poplar growing region, is now restricted to U.P. and that too to only Aligarh/Bulandshahar locations in U.P. where it does not attract infestation from Bipolaris spp. due to drier weather conditions. Some saplings of G3 clones are also reported to be grown in the drier part of Haryana. Similarly, clone G48 the most preferred clone among the growers over the great part of RIPC is not grown towards eastern limits of poplar culture especially eastward of Bareilly (U.P.) because of its high susceptibility to sap sucking insects including red mite (Dhiman, 2007). WSL22 is now becoming more acceptable in its place in many locations. Similarly, S7C8, WSL A/49 and Bahar are mainly grown in the states of U.P. and Uttarakhand and they are almost non-existent in the states of Punjab and Haryana. WIMCO has released 15 indigenously developed clones from its improvement programme and two introduced clones (G48 and G3) for field planting. Three clones, viz., Udai, Kranti and Bahar were released during the year 1992, six clones, viz., WSL 22, WSL A/26, WSL 27, WSL 32, WSL 39, WSL A/49 were released during the year 2000 and six others, viz., Wimco 62, Wimco 81, Wimco 83, Wimco 108, Wimco 109 and Wimco 110 were released during the year 2010. Many of these clones are in the data base of IPC whereas the last lot of five Wimco series clones has been sent for registration. G48 has already phased out from some locations and is declining in many others. Choice of clones being grown is specifically driven by the demand from the growers. The fact that the company still grows a few thousands saplings of some introduced and those developed by other agencies, viz., L34, S7C15, S7C8, S7C4, etc. indicates that there is some demand of these clones from the growers and are produced to meet the requirement of growers. The demand for the above mentioned clones is realistic as has been found from an exhaustive survey that was conducted in all the poplar growing nurseries in that state by the Haryana Forest Department during 2011-12 (Dhiman and Jagdish Chander, 2012). The survey confirms that G48, WSL 22, Udai were the leading clones with 95 per cent of the total stock production belonging to these clones. Yamunanagar District in Haryana is one of the main centres of poplar nursery and plantation culture and also as a main centre of poplar wood trading and its processing in the country. The outcome Forestry Bulletin, 12(1), 2012 of the survey on sapling production of clones in demand is, therefore, a realistic indicator of the choice of clones being grown. Some other interesting observations from this survey indicates that St121 and IC clones are still being grown in many nurseries and these were not recorded by the field staff during this survey. On the other hand, WSL34 and SAI43 clones recorded in the survey are not standard clones and are being ignorantly mentioned by some of the nursery growers. It is believed that most nursery growers lack knowledge and identification of the clones and they name their ETPs to any standard clone which finds market. Most poplar growers and its wood users know mainly G48 clone and many nursery growers supply their unknown origin saplings on the name of this clone. The percentage and share of clones as shown in the Fig. 2 is just indicative trend and G48 is not necessarily occupying 56 per cent share in clonal culture in the state as appeared from the data of the survey. The grower’s choice for clones has been slowly changing over the time. Poplar is now grown by numerous growers numbering a few hundred thousands in India. Many of them have planted and harvested poplar numerous times. They, therefore, have developed likings for some clones which have been grown on their fields and avoid taking risks with new clones. The farmers show great interest in new clones yet follow a conservative approach in view of emergence of many nursery growers supplying spurious planting material on the name of hybrids and tissue cultured poplar. The acceptability and adoption of new clones is, therefore, very slow and highly complex mechanism among so many growers in the country. WIMCO released its six clones, viz., WSL 22, WSL A/26, WSL 27, WSL 32, WSL 39, WSL A/49 during the year 2000 for supply to the farmers. The slow progression in the adoption rate of individual clones in this complex farmer based poplar farming is indicated in Fig. 3. It is only after a successful and better production of new clones on farmer’s fields that they start accepting good performing ones. Poplar is the most domesticated forest tree in India and has better synergy with agriculture system than forestry operations. Replacement of old clones is expected fast in this domesticated tree than in many slow growing trees. Like agricultural crops, it is strongly felt that poplar farming also needs to have continuous development of new clones which are site matched, more productive and resistant to pests. WIMCO’s poplar programme is simple but realistic technical programme which is immensely helping in sustaining poplar culture supported by numerous growers in the country. It is also a mean for livelihood for thousands of nursery growers who freely grow WIMCO’s developed clones as a part time 47 production and wood usage helps in developing operationally acceptable technologies. Integration of research and development at every level adds value to the programme. Multi-location trials being conducted on farmer’s fields act as demonstration plots and as a mean for fast acceptance of good performing clones. Further the testing of the new clones is on the actual land use where they are grown after the release. Acceptance of its numerous clones in nursery and plantation culture over its entire growing locations in the country is an indication of the success of this programme. References Fig. 2. Share of major clones in poplar sapling production in the state of Haryana. Fig. 3. Adoption rate of new clones over a decade among growers in WIMCO’s programme. business activity. WIMCO’s poplar programme is a complete package of its improvement, nursery and plantation culture integrated with agriculture crops on farm land and wood procurement. Its backward and forward linkages with nursery 48 Chaturvedi, A.N. 1982. Poplar for farm forestry in Uttar Pradesh. Indian Forester, 107: 661-664. Dhiman, R.C. 2007. Infestation of leaf curl mite (Tetranychs urticae Koch) in poplar nurseries. ENVIS Forestry Bulletin, 9(1): 132-137. Dhiman, R.C. 2012. Diagnosis of intercrops in poplar based agroforestry. Indian Forester, (Accepted). Dhiman, R.C. and Gandhi, J.N. 2006. Clonal variation in poplar wood for making match splints. Journal of the Indian Timber Development Association of India, 52(1-2): 22-25. Dhiman, R.C. and Gandhi, J.N. 2010. Field performance of traditionally propagation vis-à-vis tissue cultured poplar. Annals of Forestry, 18(2): 223-230. Dhiman, R.C. and Jagdish Chander. 2012. Expanding poplar culture and plywood industry. Plyworld, 4-5: 29-31. Kolte, S.J. 1985. Disease of annual edible oilseed crops. Vol. 3: Sunflower, saaflower and nigerseed diseases. Boca Raton, CRC Press. pp. 9-96. Kumar, D. and Singh, N.B. 2001. Age-age correlation far early selection of clones of Populus in India. Silvae Genetica, 50(3-4): 103-108. z ENVIS Status of Intercropping in Poplar Based Agroforestry in India Sanjeev K. Chauhan, R. Sharma and W.S. Dhillon* Department of Forestry and Natural Resources, *Department of Fruit Sciences Punjab Agricultural University, Ludhiana - 141 004 Introduction I Poplar (Populus deltoides) based agroforestry systems, adopted extensively by the farmers on a commercial scale, will play a significant role to meet the economic, social and environmental concerns of the people Forestry Bulletin, 12(1), 2012 ndia has made heavy investment and growth in agricultural sector. There has been tremendous increase in production area and productivity of food grains, which however, has not come without negative impact on ecology, thus, affecting the generations to come. The mankind is facing a huge challenge of meeting its basic needs of food, shelter, etc. on the one hand and conservation of natural resource on the other hand. The use of agrochemicals in agriculture crop production promised food security, but at the cost of polluting air, soil and water resources. The loss of forest land, for human habitation, developmental activities and intensive agriculture resulted in ecological imbalance. Further, the crucial support systems like soil health, air and water quality, groundwater recharge, natural control of pests, etc. are diminishing. Therefore, need has been realized to conserve the natural resources and protect the deteriorating environment so that the much needed growth in agriculture is maintained sustainably. Agroforestry is a land use system, which contributes pragmatically in all these spheres to materialize the desired goals. The unmatchable advantages and implications of this land use system have precipitated the recent concerned interest in agroforestry all around including India. Agroforestry offers not only a sustained productivity, but also its sustainability over the longer period. It buffers against the vagaries of climate through its unique way of amelioration of microclimate and reshapes the agro-ecosystem with enhanced stability and resilience. Global warming and associated problems of climate change have pressed the need for land use system that are more dependable in production and more sustainable in terms of resource conservation to ensure food security (Nair, 1991; Sanchez, 1995; Singh, 1999; Lal, 2004; Srinidhi et al., 2007). The theme of agroforestry centered around sustainability in terms of economics (productivity and profitability), ecology (environmental and resource conservation) and social issues (food security, health and safety) that make it an unparallel land use system (Pandey, 2007). The current interest in agroforestry in India has transformed the land-use system in terms of economic sustainability. Introduction of trees on farm land has not only benefited farmers but generated employment in different sectors; i.e., on-farm (nursery to harvesting of trees), wood based industries, transportation, trading, etc. and provided the wood products at affordable prices. 49 Farmers have been integrating variety of components; i.e., perennial trees (fruit/timber/fodder/fuel), livestock, apiculture, pisciculture, etc. depending upon their requirements, available resources/agro-ecological conditions (Hymavathi et al., 2010) and achieving a favourable benefitcost ratio from multiple components in agroforestry system. Continuing with the traditions, the need of the day is to plan and make intelligent investments in farming and diversify the traditional crop rotations; i.e., adopting management practices that increases biomass production and/or reduce natural resources depletion with increase in soil organic carbon. Lesser availability of land, low returns from traditional crops and the ever-increasing demand for fuel, fodder, timber, etc. are the reasons that compel farmers to integrate multipurpose tree species on their farmland. Also inter-cropping provides certain environmental benefits and enrich the soil through nutrient pumping from deep profile, return of litter and reduce soil erosion. It is well recognized that agroforestry is one among the few options that can successfully address food security, poverty reduction and environmental protection. It is a key path to prosperity of the farmers and a mean to address the changing climate issue. Current et al. (1995) reviewed 56 agroforestry practices in eight countries and found that a majority was profitable and in 40 per cent of cases, financial returns were at least 25 per cent higher than alternative farming systems. The adoption of any new system depends upon the user’s awareness, attitude, perception, capacity to take risk and capacity to overcome the constraints. The choice of trees for agroforestry system depends upon the purpose of the farmer whether to grow them for personal or industrial use. Farmers concern is the ultimate profitability from the system and he will adopt an alternative to traditional crop rotations only if it assures higher returns. Sharma and Kumar (2000a); Nouman et al. (2008); Chauhan et al. (2009a) have reported that in spite of good economic realization from poplar based agroforestry systems, farmers fail to adopt the intervention due to low awareness, unfavourable attitude and lack of capacity to over come constraints; (i.e., land holding, technical know how, financial support, legal, social, etc.). Poplar Based Agroforestry Agroforestry is emerging as one of the diversification options for farmers in irrigated agro-ecosystem in north-western states in India. It is a refined concept in this region where land units are deliberately so managed under trees and crops, with or without animals, that the system is scientifically sound, practically feasible, economically viable, socially acceptable 50 and ecologically desirable/sustainable. Agroforestry is a resource-conserving, not depleting system compared with the existing land management systems involving few crops like rice, wheat, sugarcane, cotton, etc. which are extremely resource-exhaustive, be it in terms of natural, financial or human resources. The most common crop rotation (ricewheat) in the irrigated agro-ecosystem in Punjab, Haryana and adjoining states is over exploiting the water resources as a result the water table has been receding at an average rate of over 42 cm per year (Aulakh, 2005). In the coming years, the tree-based direct needs will exclusively be met from farm forestry or agroforestry, and poplar (Populus deltoides) based agroforestry systems, adopted extensively by the farmers on a commercial scale, will play a significant role to meet the economic, social and environmental concerns of the people. Poplar has become the most preferred cash crop in north-western states (Chandra, 1986). Almost any crop (cereals, pulses, vegetables, forage, fruit/vegetable crops, etc.) can be grown with it (Sharma, 1996; Chauhan and Mangat, 2006). It is one of the world’s fastest-growing industrial soft woods, which can be harvested within a reasonably short period of 5-8 yrs. Poplar intercropping is a highly profitable venture as much as poplar growing is a highly lucrative business since market for its products are readily available because of established processing industries in the region (approximately 1,200 units of all category in Punjab, Haryana, Delhi, Uttarakhand, Uttar Pradesh, etc). The deciduous nature of the tree with slender crown and straight clean stem, permits culture of a variety of seasonal and annual agricultural crops, depending on their age, geometry of planting, season, etc. Poplars being sensitive to waterlogged conditions can check the vicious cycle of wheat-paddy rotation, which is responsible for the lowering of water table and becoming unsustainable for crop production in this region. For intercropping, the spacing for poplar plantation is generally kept at 5 m x 4 m, which allows mechanical ploughing and other operations without any difficulty. It is planted either on field bunds/along irrigation channels in single rows (boundary planting) or in the field as pure block planting. Kharif crops do not remain profitable during older age (3rd year onwards) of plantations, nevertheless, rabi crops can be grown till the harvesting, as they get sufficient sun light due to complete leaflessness of poplar. Further with the meager area under forests that too of degraded condition coupled with the restriction on felling puts poplar in price driving position. Being a major raw material available to plywood industry of the region, it has sustained demand and market. With intensive management of poplar based ENVIS agroforestry models, presently, the farmers are getting better financial returns than from other cropping rotations. It has not only benefited farmers but also helped the wood based industry and employment of various kinds. The number of agricultural crops (wheat, mustard, turmeric, ginger, colocasia, cabbage, potato, spinach, garlic, etc.) including fruit crops (citrus, guava, mango, etc.) can be profitably raised with poplar (Sharma, 1996). While few crops like sugarcane, sorghum, soybean, mentha, etc., can be grown only during initial two years. The scanty information available, reflects the positive response in some crops and inverse trend with others when raised under varied tree canopies (Gandhi and Joshi, 2002; Chauhan et al., 2005, 2007; Chauhan and Mangat, 2006). Poplar based agroforestry models whether block or boundary are popular in the irrigated agro-ecosystem throughout the north-western states in India, with some region-wise variations in the inter-crops (Dogra et al., 2007; Chandra, 2011). Trees for industrial use are catching the attention of farmers to grow economically and poplar based agroforestry systems have proven worth in north-western states of India (Newman, 1997; Chauhan and Mangat, 2006; Chandra, 2011). Dhiman (2012) identified intercrops grown in poplar based agroforestry and reported that around 98 per cent of the poplar block plantations grow intercrops and only a few absentee land owners or casual growers avoid intercrops. Success stories of poplar plantations have not only been reported in India but world over (Ranasinghe and Mayhead, 1990; Burgess et al., 2000; Chaudhry et al., 2003; Ball et al., 2005; Gautam and Thapa, 2007; Nouman et al., 2008; Rivest et al., 2009; Christersson, 2010; Henderson and Jose, 2010; Pearson et al., 2010). Around one million people in Siyang county in China are benefiting from poplar plantations. China is presently world’s biggest poplar growing country (8 million ha) followed by France, thus engaging farmers in income generating activities, development of wood based industries, job creation, etc. for economic development of rural as well as urban residents (www.fao.org/news/story/en/item/44518). Silvo-arable Forestry in Europe Project (www.montpellier.inra.fr/safe) has emphasized the importance of the species in different European countries for timber production, renewable energy and scope for economically viable intercropping. Some of the potential benefits and services provided by poplar based agroforestry technologies that virtually contribute towards achievement of sustainable development and ensure food security in Northwestern states of India without depleting the natural resource base have briefly been Forestry Bulletin, 12(1), 2012 reviewed in this paper. Cautiously, the studies reported in the country report (India) of National Poplar Commission, (2008-2012) have been avoided (NPC, 2012). Lot of work on varied aspects of tree-crop interaction (need based and site specific); i.e., productivity, geometry of planting, pruning, nutritional; requirements, socio-economic aspects, above and below- ground interaction, carbon sequestration, etc. have been reported on poplar based systems and it was little difficult to comprehend vast literature and include in this paper, therefore, authors restricted to their own data with supportive latest references. Poplar and Wheat Crop Intercropping There has been much emphasis to diversify the traditional crop rotation of rice-wheat and more specifically rice, to capture better financial returns and sustainable management of natural resources. On system basis, the trees and crops can generate higher returns on unit area. The silvo-arable agroforestry for Europe has shown that one hectare planted with alternate strips of poplars and wheat, produced the same output as 0.9 ha of wheat and 0.4 ha of poplar (Brelivet, 2006). Though, intercropping is complex but winter crops in poplar based system have been found successful due to the leafless nature of the poplar trees during winters. Tree based mixed systems are reported more productive than monocultures, especially when trees obtain resources that would, otherwise, be unavailable to the crops. However, some adverse effects due to allelopathy have also been reported by various scientists (Kaur and Rao, 1988; Kohli et al., 1997; Singh et al., 1998, 2001; Sharma et al., 2000; Kaushal et al., 2003; Nandal and Dhillon, 2007). Poplar being deciduous in nature is more favourable for winter crops when shading is not a problem and sunlight is available to the under storey crops. By the time poplar develops their foliage, the under storey wheat crops have virtually completed vegetative growth and enter into reproductive phase. Wheat-poplar intercropping has been extensively studied and it started very early (Tiwari, 1968) but focused emphasis was given in eighties and it is continuing till date with variation on different need based aspects of investigation; i.e., geometry, crop varieties/tree clones, fertility, tending, crop quality, productivity, carbon sequestration, economics, etc. Wheat is one of the main crop of poplar growing region and therefore farmers are usually reluctant to leave it. Further, adoption of poplar-wheat model is common because of extensive research on model, food requirements and minimum support price attached with the crop for ensured marketing. Though, Tiwari (1968) reported drastic reduction in wheat crop yield but Sheikh et al. (1983) and Sharma et al. 51 (2001) did not observe significant influence of poplar tree competition for resources on wheat crop. Instead, Dhadwal and Narain (1984) observed increase in crop yield with poplar trees on the boundary instead of block plantation. Shading has significant influence on crop productivity. Pendleton and Weibel (1965) reported 37, 70 and 99 per cent decrease in crop yield at 30, 60 and 90 per cent shading, respectively from early spring to harvesting. Increase in distance between the tree rows minimizes the competition for growth resources (Chauhan and Dhiman, 2002). Spacing of 5x5 m is appropriate for crop yield and tree productivity but 5x4m is preferred to accommodate more number of trees for better overall economics with insignificant loss to crop and trees (Gandhi and Dhiman, 2010). There is direct relation of crop and tree productivity with increase in row spacing (Chauhan and Dhiman, 2002), which governs the light for the under storey crops. Pruning of lower branches second year onwards not only benefits the trees but intercultivated crops as well through increased value of large clear bole and penetration of more relative illumination, respectively. There is strong relationship between stem volume/basal area and crown surface area (Mishra and Gupta, 1993). Topping to discourage height growth in favour of diameter growth itself is not successful in poplar because it leads to forking due to apical dominance with no additional benefit in diameter. Age of poplar (P. deltoides) trees is recorded as the most important factor influencing grain yield of intercropped wheat (Chauhan et al., 2009a). On an average, reduction in grain yield (var. PBW 343) was 20.10 per cent under 1-yr old poplar plantation, which increased to 54 per cent under 4-yr old plantation. While comparing the crop yield under block and boundary planting models, wheat and paddy yield (grain and straw) substantial reduction was recorded in poplar based system than the tree-less plots (Fig. 1). The grain yield of wheat crop was maximum under control plots; i.e., 4.55t per ha, which was higher than the crop grown under boundary G rain Yield & S traw yield (t/h (t/ha) B oundary plantation B lock plantation C ontrol 12 10 8 6 4 2 0 G rains y ield S traw y ield W heat (t/ha) G rains y ield S traw yield Ric e (t/ha) Fig. 1. Grain and straw yield under different planting methods. 52 plantation (3.28 t per ha) and lowest at block plantation (2.03 t per ha). During summer season, rice is grown in control and boundary plantation, whereas, no crop is grown in block plantation (poplar does not tolerate stagnating water). The higher grain yield of rice was attained in treeless area (7.42 t per ha) than in the boundary plantation (4.74 t per ha). Similarly, trend was recorded for straw yield in wheat and rice (Chauhan et al., 2012a). The reduction in boundary plantations, however was variable on different row directions due to more shading effect on south-western rows than north-east rows. In the changing climatic conditions, varietal evaluation has been taken up for their suitability under tree canopy. Singh et al. (1993) recorded yield reduction in the order of PBW34 (57.71 per cent)> PBW-222 (19.14 per cent)> HD 2329 (15.3 per cent). Pannu and Dhillon (1999) recorded maximum yield of PBW-226 variety of wheat under poplar, while CPAN 3004 performed very poor under the tree canopy. Among the six newly developed wheat varieties, PBW 502 out performed in terms of yield and nutrient uptake. Date of sowing itself influence the crop yield, which is governed by the leaf shedding period (Zomer et al., 2007). First week of November was found more suitable for the sowing of crops because by this time leaf shedding is complete, otherwise, the leaf shedding affect the germination of crop if sown before November (Gill et al., 2009) and germination/growth itself is affected if sown late due to lower temperature during December-January. Singh et al. (1999) and Kumar et al. (2001) observed that fallen leaves are one of the factors that adversely affect the growth of wheat crop. Similarly clonal differences for influence on wheat crop have also been recorded (Puri and Sharma, 2002; Mishra et al., 2006). Poplar planted in rows in any direction has no significant effect on yields of crops upto 4th year of planting (Calstellono and Prevoster, 1961), but Chauhan et al. (2007) recorded significant directional effect on wheat/paddy crops and north-south row orientation is recommended for more insulation to the under storey crops. Crop yield, declines as the poplar tree age increases (Ralhan et al., 1992). Wheat yield reduction from 10 to 50-60 per cent has been reported by Puri and Bangarwa (1992) and Chauhan et al. (2009a, 2012a). The increase in age of poplar trees is associated with root and canopy development, which causes intense competition for light/nutrients/water, etc. thus reduces crop yield with increase in age than open condition. However, yield reduction is not only due to the competition between inter-cultivated components but also due to allocation of approx. 10 cent land to poplar trees. Studies have inferred competition between poplar tree and crop roots for soil resources due to ENVIS shallow tree roots, thus, leading to yield depression (Puri et al., 1994). A study was conducted to standardize the appropriate planting technology for better plant growth with minimum root competition with inter-cultivated crops. The poplar plants were uprooted after one year of planting to study the rooting behaviour. It was observed (Table 1) that the planting of poplar ETPs in 1m3 pit had better above as well as below ground growth in comparison to traditional auger hole planting (1m deep, 15cm diameter). On physical observation, it was noticed that the polythene sheet did not allow the roots to extend beyond the polythene lining and the root fibrosity was more in comparison to the pits without polythene lining, where roots extended horizontally on the top layer (Fig. 2). But during second year, it was observed that the roots have extended beyond the polythene lining, which indicates that we need to apply polythene lining with different thickness around the plants or create some other barrier to avoid the tree-crop competition. Digging trench around the trees would not be a viable alternative since it would lead to wastage of productive land and hinder crop cultivation as well. The conservation of natural resources is an area of concern for sustainable productivity and micro-environmental conditions are also modified under the canopy (Fig. 3). It has been observed that air as well as soil temperature is low while the humidity remains higher under tree canopy, which itself has generated the interest for future research for adaptation to changing climate (Rani, 2009; Dhillon et al., 2010, 2011; Rani et al., 2011; Chauhan et al., 2012b). Gupta et al. (2005) recorded no significant depletion of ground water level in poplar growing areas in Uttar Pradesh State. The deciduous phenology of poplar minimizes the evapo-transpiration, which contributes considerably to its low water impact on water use rather improves water productivity with a dormancy period that corresponds with the peak growth of winter crops (Zomer et al., 2007). Earlier Burgess et al.(1996) also reported little competition for moisture between poplar and wheat crop. Rani (2009) recored better crop productivity on raised beds than normal sowing, thus saving significant amount of water. Poplar litter serves as a potential source of organic inputs where the biogeochemical nutrient cycling is dominated by litter production and decomposition. Singh and Sharma (2007); Gupta and Pandey (2008); Gupta et al. (2009); Chauhan et al. (2010a, b) observed significant increase in organic carbon in older plantations than young Table 1. Planting technology for reduced root competition with the intercrops (ICAR, 2010) Pit size Plant height (m) Collar girth (cm) Root spread (m2) Total root fresh weight (kg) Lateral root fresh weight (kg) Root number Total stem dry weight (kg) Auger hole 1m (15cm diameter) 5.5 16.7 4.4 1.4 0.70 35.7 1.4 45cm pit + auger hole 55cm 5.9 18.0 4.5 1.7 0.81 24.8 2.1 1m 3 pit 6.0 24.0 6.7 2.8 1.42 32.3 4.9 45cm pit with polythene lining +55 cm auger hole 5.0 19.7 5.4 2.5 1.07 38.7 2.5 1m 3 pit with polythene lining 5.8 21.0 6.1 2.2 0.94 31.5 2.6 CD 5% NS NS 1.5 NS NS NS 1.73 1 m3 pit without polythene lining 1 m3 pit with polythene lining Fig. 2. Rooting behavior of poplar roots. Forestry Bulletin, 12(1), 2012 53 PAR-open T air-canopy PAR-canopy RH-canopy T air-open Rh-open 80 1600 75 65 PAR (umol/m2/s) 60 55 50 1200 45 40 1000 35 RH(%)/Air Temperature(° C) 70 1400 30 25 800 20 45 52 59 66 73 80 87 94 101 108 115 122 130 Days Daysafter afterSowing showing Fig. 3. Micro-environmental parameters in open and under poplar tree canopy (Dhilllon et al., 2007). during June-August increases the decomposition rate and their availability to the under storey crops. Das and Chaturvedi (2005) recorded a range of 37.3-146.2 kg N, 5.617.9 kg P and 25.0-66.3 kg K per hectare in 3 and 9-yr old plantations, respectively. However, there is also removal of nutrients from the system on harvesting of poplar trees. Tandon et al. (1991) calculated 533, 15, 627, 545 and 229 kg/ ha removal of N, P, K, Ca and Mg, respectively. Durai et al. (2009) also recorded removal of substantial amount of nutrients from the system through pruning (46.32 kg N, 6.92 kg P and 19.93 kg K per hectare) and timber harvest (652.8 kg N, 75.84 kg P and 719.84 kg K per hectare). Since, the nutrient removal exceeds annual return, therefore, additional doses of fertilizers are recommended to maintain the soil fertility and sustainability in land productivity. Poplar and Other Agricultural Crops Intercropping ones. Micro as well as macro-nutrients also increase under plantations than intensive crop cultivated area, Fig. 4 shows substantial increase in nutrients on the top layer (Sharma et al., 1998; Dhillon et al., 2012). Poplar leaves decompose fully in 20 and 17 months in surface and subsurface layer, respectively (Kaushal et al., 2005). The higher calcium concentration in poplar leaf litter is one reason for slow decomposition rate. The release of nutrients from decomposition of poplar litter during winter months is quite less but increase of ambient temperature and moisture The diversification of crops under poplar canopy itself is essential to harness higher income than poplar-wheat model. It is important to explore the possibilities of low volume high value crops for the economic betterment. Because, low prices of poplar wood during 2002-2005 in India have not only affected the profits of the intercropping system but confidence as well, thus, forcing the farmers to wait for additional years to harvest/ go for distress felling, or look for alternative options. Therefore, crops other than wheat have equally been advocated excepting rice to ensure regular/enhanced income and indirect Fig. 4. Availability of various nutrients in different trials at different depths of the soil (Dhillon et al., 2012). 54 ENVIS benefit to the poplar trees for nutrients, water, weeds control, root aeration, etc. As mentioned earlier, usually crops like sugarcane, cereals, pulses, oilseed, vegetable, fodder, fruit crops, etc. are intercropped with poplar. Chaturevdi (1983); Mathur and Sharma (1983a, b); Jones and Lal (1989); Singh et al. (1990) highlighted the cultivation of diverse crops under poplar by the farmers though at that stage much research inputs on different crops were not available and farmers have been raising traditional crops as per their suitability, which became the basis for further refinement. Due to deciduous nature of the tree, winter crops are grown through out the rotation period but third year onwards during summer; only fodder/leafy/rhizomatous crops are grown. Poplar though does not tolerate stagnating water, therefore is an option to replace rice cultivation. Still the farmers are reluctant to leave rice cultivation and rice can be cultivated with refined cultivation (direct seeded rice) and planting technology (bund plantingboundary/block). As diversification option, Chauhan (2000); Raj et al. (2010) reported very successful cultivation of lemon grass under poplar. Chandra (2001) recorded 27.5t per ha and 15t per ha yields of lettuce and beet root, respectively under poplar. Pitcholi and Tagetes also yielded sizable quantities of oil per unit area under young poplar trees. Gandhi and Joshi (2002) earned Rs 0.4 million from the inter-cultivation of strawberry per annum. Gill et al. (2008) observed substantial reduction in Mentha arvensis (64.9 per cent), M. spicata (65 per cent), coriander (26.7 per cent) but reduction in other medicinal and aromatic crops (fennel, Tagetes, lemongrass, dillseed, turmeric and fenugreek) was not substantial. Dhiman and Gandhi (2010) recorded significantly comparable yield of G50 variety of garlic under poplar than open conditions. Similar observations have been presented in Fig. 5 (ICAR, 2010). The influence on crop have been due to the ecological interaction of both the integrating components, which could be positive or negative. Tree canopy modifies Fig. 5. Yield attributes of garlic and onion as influenced by poplar canopy (ICAR, 2010). Forestry Bulletin, 12(1), 2012 the microclimate and influences the physiological processes of understorey crops. Under tree canopy, the photosynthetic active radiations (PAR) and temperature decreases while humidity increases (Chauhan and Dhiman, 2007; Rani et al., 2011; Chauhan et al., 2012a). PAR under the canopy is crucial in producing grains, however, some rhizomatous crops; i.e., turmeric (Curcuma domestica) and colocasia (Colocasia esculenta) have been found more suitable under tree canopy (Lal, 1991; Jaswal et al., 1993; Dhillon et al., 2009; Pant et al., 2010; Chauhan et al., 2011a, 2012c). These crops have successfully been grown and adopted by the farmers. To minimize resource competition and improve physiological processes of crops, such as turmeric, colocasia, ginger, etc. canopy management is essential to ensure better yield under poplar-based agri-silvicutural system. In turmeric and colocasia, photosynthesis rate under poplar canopy was observed to be maximum during noon, whereas, the rate of photosynthesis in the open was maximum at 9:00AM. Under the canopy, the photosynthesis rate was proportional to available PAR (Table 2). The same was not observed in open as the minimum stomatal conductance was observed during noon (Dhillon et al., 2009; Chauhan et al., 2011a), which means that photosynthesis occurs more during noon than morning and evening under tree canopy. However, the yield under the canopy, though reduced but was not drastic. Yield was proportionately related to micro-environmental changes in light, temperature, humidity, etc. under canopy (ICAR, 2010). Fruit trees (mango, citrus, litchi, ber, pear, guava, etc.) based agroforestry models are also becoming popular, as the forest tree component will be harvested by the time fruit trees start commercial bearing. There was not much change in fruit development under canopy than open condition (Fig.6), such behaviour was observed in pear and plum as well (ICAR, 2010). It has caught the attention of the farmers not only in Punjab, but also in other adjoining states of Haryana, lower areas of Himachal and terai area of Uttarakhand. Some progressive farmers have earned handsome income through the adoption of horti-silvicultural interventions. The economics of such systems is better than the traditional crops in agroforestry (cereal/pulses/oilseed based agroforestry models). Flower seed production during winter months have been found quite remunerative (Chauhan et al., 2010c; Rani et al., 2011). Additionally, some complex models including apiculture and pisciculture components have also been advocated and practically adopted as well to enhance the financial gains. 55 Table 2. Diurnal variation in eco-physiological parameters of turmeric and colocasia crops (Dhillon et al., 2009; Chauhan et al., 2011a) Time PAR (μmolm-2s-1) Photosynthesis rate (μmolm-2s-1) Transpiration rate (mmolm-2s-1) Stomatal conductance (mmolm-2s-1) Temp. air (oC) Temp. leaf (oC) Internal CO2 (ppm) Turmeric under canopy 9AM 240.27 12 Noon 487.06 4PM 119.40 3.30 5.20 2.02 0.91 2.71 1.54 112.92 239.16 149.48 31.10 33.20 32.27 32.00 35.17 33.00 373.23 321.27 404.77 Turmeric without canopy 9AM 648.38 12Noon 1005.77 4PM 554.63 11.19 3.69 1.61 1.19 3.69 1.69 154.21 220.25 27.71 36.42 34.70 38.57 39.76 39.40 44.60 264.90 313.67 372.13 Colocasia under canopy 9AM 276.78 12 Noon 529.34 4PM 125.83 0.75 2.12 1.61 0.53 2.73 1.04 156.87 277.14 124.03 31.30 35.16 33.00 32.18 36.96 35.75 374.85 368.03 335.70 Colocasia without canopy 9AM 676.20 12 Noon 1110.80 4PM 538.13 12.82 5.12 9.44 3.52 4.26 2.80 161.27 82.27 181.88 34.23 39.57 35.43 38.63 43.67 38.60 341.97 190.33 374.07 1 2 3 4 Fig. 6. Fruit development in guava under open (1 and 2), and under poplar canopy (3 and 4). Performance of Poplar and Biomass/Volume Estimation Intercropping of agricultural crops with poplar generally has no adverse effect on tree growth rather intercropping enhances tree growth. Poplar plantations associated with 56 agricultural crops show better productivity and economics than the pure plantations (Table 3). Dalal and Trigotra (1983); Mathur and Sharma (1983a); Singh et al. (1988); Jha and Gupta (1991); Ranasinghe and Mayhead (1990); Chaturvedi (1992); Chaudhry et al. (2003); Verma (2008) observed that there was high production of wood in poplar when cultivated with ENVIS Table 3. Growth and biomass of three-year old poplar under agroforestry and sole plantation Tree height (m) DBH (cm) Crown diameter (m) Crow n height (m) Fresh timber weight (kg/tree) Total fresh biomass (kg/tree) Agroforestry plantation 15.7 16.1 4.1 9.1 80.1 178.4 Sole irrigated poplar plantation 13.5 14.7 3.8 7.7 73.3 163.3 seasonal agricultural crops due to the benefit drawn by the poplar plantations from various agricultural inputs like fertilizers, irrigation and proper management of soil. Dickman and Stuart (1983) observed that poplar trees were benefited from the intensive site preparation and fertilization required to grow agricultural crops and, in their turn, provide some protection for seasonal crops. Trees grown under forest conditions could not receive proper tillage and manurial requirements, thereby, resulting in poor performance. Furthermore, trees planted in and around the edges of fields were regularly ploughed and planted with agricultural crops and hence develop vigorous roots, attain more height, diameter and timber. The higher returns in poplar with intercropping are mainly due to higher productivity of poplar than without intercropping (Dhillon et al., 2001, Chauhan and Mahey, 2008). Better tree growth is recorded at wider spacing than 20m2 per tree recommended space (Chauhan et al. 2008; Gandhi and Dhiman, 2010) but Khan and Chaudhry (2007); Chauhan et al. (2010a, b, 2011b) reported more biomass on unit area basis at lower spacing than recommended one though per tree biomass was less. However, Burgess et al. (2004) recorded adverse effect on tree growth by the arable treatments due to competition for water/nutrients and damage to the trees during cultivation. Poplar grows rapidly during initial three to four years and any stress during this period is difficult to cover up. Poplar shows marked effect of irrigation and intercropping. The growth of poplar in different regions presented in Table 4 was found almost the same over the rotation period in all the different regions excepting in semi-arid region (Dogra et al., 2007). The increment in height as well as DBH starts declining third year onwards. Chauhan et al. (2012a) reported increase in biomass MAI up to 4-4.5 yrs and, thereafter, it decreased (Fig. 7), which is the suitable time for its harvesting. Biomass distribution in different tree components at different ages has been presented in Table 5 to workout economics and carbon sequestration potential of the species. Poplar wood is sold on fresh weight basis and therefore, it is important to know the standing fresh weight of the trees/stands to ascertain their market value. Number of volume/biomass estimating tables have recently been developed (Singh and Upadhyay, 2001; Rizvi and Khare, 2006; Zabek and Prescott, 2006; Gautam and Thapa, 2007; Sharma et al., 2007; Rizvi et al., 2008a, b, 2010; Dhillon et al., 2011; Ajit et al., 2011) but their area of applicability and the range of trees dimensions are limited thus creating problem in assessing periodic economic values as well as carbon sequestration potential. Since, the clonal differences are evident in different growth and quality parameters (Chauhan et al., 2008; Pal et al., 2009; Pande, CAI (Total dry biomass) 80.00 70.00 Dry biomass (kg/tree) Environments MAI (Total dry biomass) 60.00 50.00 40.00 30.00 20.00 10.00 0.00 1 2 3 4 5 Poplar age (years) Fig. 7. Current and mean annual increment in dry biomass in poplar trees of different ages (Chauhan et al., 2012a). Table 4. Poplar growth in different regions in Punjab (Dogra et al., 2007) Tree age (yrs) 1 2 3 4 5 6 Ludhiana (flood plain-bet area) H eight (m) DBH (cm) 6.64 5.83 9.90 11.64 18.04 17.51 20.04 21.00 21.80 21.37 21.98 22.00 Forestry Bulletin, 12(1), 2012 SBS Nagar (Shiwalik foothills-irrigated) H eight (m) DBH (cm) 4.93 5.36 11.98 11.29 15.44 14.37 18.12 18.26 20.30 19.20 22.58 21.75 Amritsar (North central) Height (m) DBH (cm) * * 11.80 10.56 14.66 15.92 16.37 18.27 17.57 21.53 20.96 22.60 Bathinda (semi-arid) Height (m) DBH (cm) 4.81 5.42 9.48 10.17 11.59 12.40 15.43 14.56 * * * * 57 Table 5. Growth and biomass partitioning of poplar trees of different ages 1 2 3 4 5 C D 5% T r ee h eig h t (m ) D B H (cm ) 6 .6 9 .9 1 8 .0 2 0 .0 2 1 .8 0 .5 5 .8 1 1 .6 1 7 .5 2 1 .0 2 1 .4 0 .6 C lear bo le (m ) C ro w n sp rea d (m 2 ) T im b er 2 .9 2 .9 3 .8 4 .4 6 .5 0 .4 8 .0 2 2.8 3 8.0 4 5.3 5 6.6 3 .1 3 .8 2 1.5 6 8.2 1 07 .3 1 15 .3 1 3.4 2011; Pande and Dhiman, 2011), therefore, comprehensive clone-wise volume/biomass tables with broader practical applicability are still required. It would be more appropriate to develop biomass table on the basis of basal area at collar region instead of breast height for easy measurements by the illiterate farmers. Diameter at breast height was standardized (1.37 m above ground level) to avoid inconvenience for measurements in forests, which is not the situation in agroforestry plantations. Poplar Based Agroforestry Farms as Carbon Sinks The practice of agroforestry is not only the way for addressing poverty, hunger, malnutrition, etc. but also the deteriorating environment. Fast growing trees including poplars have an important role for capturing atmospheric carbon dioxide to ameliorate environment. The emerging carbon market may provide a new viable option for land owners provided that carbon prices are high enough to make growing trees a worthwhile investment than existing land uses and the procedures, for trading of carbon sequestered in trees on small farms in fragmented holdings, are simplified for easy documentation and trade. Several studies have shown that the inclusion of trees in the agricultural landscapes often improves the productivity of systems while providing opportunities to create carbon sinks (Schoreder, 1994; Pandey, 2002; Montagnini and Nair, 2004; Chauhan et al., 2007; Newaj and Dhyani, 2008; Jose, 2009; Schoeneberger, 2009; Nair et al., 2010; Sharma and Sharma, 2011). The amount of carbon sequestered largely depends on the agroforestry put in places, the structure and function, which to a great extent are determined by environmental and socio-economic factors. The carbon sequestration potential for agroforestry practices is more variable, depending on the planting density, production objective, components in system, productivity, etc. Actually, the carbon storage in plant biomass is better feasible in the perennial agroforestry systems (perennial-crop combinations, agroforestry, windbreaks, hedgerow 58 D ry bio m a ss (kg /tree) B ra n ch w o o d S m a ll w oo d (lo ps a n d to p s) 0 .6 1 .2 3 .5 4 .5 8 .4 6 .9 1 3.1 9 .7 1 3.3 9 .4 4 .0 1 .8 L a teral roo ts 0 .1 1 .0 5 .8 1 0.9 1 2.5 2 .2 intercropping, horti-silvicultural system, etc.), which allow full time tree growth where the wood component represents an important part of the total biomass. However, the cost of carbon sequestered through agroforestry appears to be much lower than other CO2 mitigation options. The area under the poplar is increasing every year because of huge demand for its wood from industry. Dhiman (2009); Singh and Lodhiyal (2009); Rizvi et al. (2010); Yadav (2010); Zang et al. (2010); Sharma and Sharma (2011); Benbi et al. (2012) also suggested great potential of poplar based intercropping systems in reducing the atmospheric CO 2 concentration compared to sole cropping systems. However, data is insufficient, and an understanding of plant/climate relationships is essentially required to guide the future policies. Some studies have been conducted to explore carbon sequestration potential in poplar-wheat based system. Total CO 2 assimilation by the biomass in the poplar-wheat based agroforestry system and monocropping of poplar and wheat was estimated at 28.6, 17.2 and 17.8t per ha per yr, respectively (Fig. 8). Therefore, even when only the accumulation of biomass carbon is considered, an agri-silvicultural system is very efficient in terms of carbon sequestration (Chauhan and Chauhan, 2009). However, these figures hold true if harvested products are transformed into durable products. Litter (leaves, branches and bark) and roots are added and 250 Sole wheat Wheat under poplar 200 CO2 fixation (tonnes/ha) T ree a g e (y rs) Poplar Poplar + wheat 150 100 50 0 1 year 2 year 3 year 4 year 5 year 6 year 7 year Age of plantation Fig. 8. Total CO2 assimilation (t ha-1) by poplar-wheat (above- and below-ground biomass) in agroforestry system and sole wheat cultivation (Chauhan and Chauhan, 2009). ENVIS allowed to decompose in the soil to sequester carbon. Gera et al. (2006, 2011) reported 66 and 37 t per ha carbon sequestration potential (2.20 and 1.37t C per ha per yr, respectively) under poplar block and poplar boundary plantations, respectively. Chauhan et al. (2010a) after seven years of poplar growth, estimated timber carbon content of 23.57t per ha, whereas, carbon content of the roots, leaves, and bark was 23.9t per ha and branches 15.01t per ha. Hence, total biomass carbon storage after seven years was equivalent to 62.48t per ha (8.92t per ha per yr). The combined contribution of poplar and wheat was substantially high within the intercropping system. This may be due to the additional carbon pool in the trees and the increased soil carbon pool resulting from litter fall and fine root turnover. The high carbon storage may also be due to the increased growth and assimilation rates of intercropped components as compared to monocropping systems. Moreover, poplar timber locks up carbon in its wood products for longer periods, thereby making it the major carbon assimilator of this type of agroforestry system. Poplar-wheat based agroforestry system, thus fare better than traditional agricultural systems, providing the best land use option for increased carbon sequestration. Clonal variation in carbon sequestering has been recorded in poplar clones by Pal et al. (2009). The WIMCO22 clone was the best in terms of sequestering carbon stock, while WIMCO-42 was the poorest one in this respect. The carbon content in different components estimated by Chauhan and Chauhan (2009) were found to range from 44.08 to 47.82 (stem, branches, root, leaves and bark values were 45.67, 46.56, 47.82, 44.08 and 46.93 per cent, respectively). Rizvi et al. (2011) estimated 27-32t/ha and 66-83t/ha carbon storage in boundary and block poplar plantations, respectively at a rotation of seven years. Dhiman (2009) estimated that only 1.04 mt C out of 2.5 mt C from poplar production system in India is locked in wood based products for different durations and the remaining is released back in the form of fuel and only a marginal fraction of 0.3 mt C is added to soil through leaf litter every year but Benbi et al. (2012) reported that poplar based agroforestry system contains higher concentration and greater stock of soil organic carbon than maize-wheat and rice-wheat system but majority of organic carbon (56-60 per cent) is in an easily oxidizable form, which could be easily lost with change in landuse. Gupta et al. (2009) found that the average soil organic carbon increased from 0.36 in sole crop to 0.66 per cent in P. deltoides (poplar) based agroforestry soils. The soil organic carbon increased with increase in tree age. The soils under agroforestry had 2.9-4.8 t per ha higher soil organic carbon than in sole crop. The poplar trees could sequester higher soil organic carbon in 0-30 cm profile during the first year of their plantation (6.07 t per ha per yr) than the subsequent years (1.95-2.63 t per ha per yr). The sandy clay soil sequesteresd higher carbon (2.85 t per ha per yr) than in loamy sand (2.32 t per ha per yr). The carbon proportion in system is also enhanced through exerting check on soil erodibility by tree roots. Top layer, which contains higher proportion of organic matter, is protected (Gupta et al., 2006). The dispersion ratio, erosion ratio and water stable aggregates increased with increase in age of poplar plantations. However, it is important to mention that less than 50 per cent of the total timber is locked for longer period and remaining biomass is used as fuel to meet the energy requirements and replaces fossil fuel. Therefore, an estimate of carbon sequestration for wood used for energy as well, was calculated (Table 6) and it was found that poplar block and boundary plantation sequester substantial amount of carbon in long lived biomass and replace fossil fuel (5.45 and 1.84t per ha per yr in poplar based system with block and boundary plantations, respectively). Realization of carbon sequestration payments will encourage landholders to adopt less intensive practices. However, the price of carbon must be high enough to encourage farmers to invest in growing trees than continue practicing traditional land use. At present, poplar based Table 6. Carbon sequestration in poplar based agroforestry models Treatments* Total biomass** (t/ha) Block plantation Long lived timber C storage (ton C/ha) Heat from biomass combustion (x109 ) Trees + wheat straw 154.3 18.7 2041.4 Trees without wheat 125.7 18.7 1525.7 straw Boundary Trees +wheat 101.8 4.4 1657.4 plantation + rice straw Trees + rice straw 72.8 4.4 1135.8 Trees without 30.1 4.4 367.9 rice and wheat straw * calculations made with the presumption that wheat straw is used as fodder, whereas rice straw is used as fuel ** tree and crop (grain + straw) biomass *** includes soil as well as long lived carbon storage in timber Forestry Bulletin, 12(1), 2012 Carbon storage from coal substitute (ton C/ha) Total C sequestration*** (t C/ha) Total C sequestration (t C/ha/yr) 34.3 25.6 55.4 46.8 9.2 7.8 27.8 32.7 5.5 19.1 6.2 23.9 11.0 4.0 1.8 59 agroforestry systems are becoming very popular amongst farmers due to substantially higher economic returns from timber than the traditional crop rotation of rice and wheat, the environmental benefits are yet to be realized. Preliminary studies by Gera et al. (2011) observed better IRR with carbon benefits than without carbon benefits in poplar based system (block and boundary plantations) but there are certain reservations on the part of farmers (continuity in adoption of tree-crop interface, transaction costs in developing agroforestry carbon project, technical/ marketing/legal guidance, etc.) in CDM projects. Policy initiatives can benefit the farmers to earn from carbon market and mitigate the green house gases to ameliorate the environment. Economics Studies in Poplar Based Agroforestry Models The success of agroforestry system/model depends upon its adoption by the farmers who are concerned about its ultimate economic viability. New interventions are only adopted if they are economically remunerative than the old ones. Farmers are planting poplar on their land (bunds or block depending on their resources) for additional income from trees. However, to raise trees on agricultural land, the interspaces between tree rows are not compromised and crops are raised to meet their livelihood requirements and also for maintenance of trees. Inter-cultivation also supports the poplar trees for their better growth due to the various inputs to agricultural crops like fertilizers, irrigation and other management practices. The higher returns in poplar based intercropping are mainly due to higher productivity of poplar than without intercropping (Dhillon et al., 2001; Chauhan and Mahey, 2008; Bangarwa and Wuehlisch, 2009). Substantial lower poplar growth in uncultivated land than with crop cultivation have been recorded by Verma (2008) and Gill et al. (2008). Poplar based agroforestry can supply inexhaustible raw material. On an average 20m3 per ha per yr wood is produced and with suitable crop combinations, the profitability has gone very high, thus, encouraging farmers for its adoption. Poplar has played a significant role in enhancing the income of the farmers and average economic returns per hectare of poplar based agroforestry is two to five times more than traditional crop rotation (Joshi, 1996; Dwivedi et al., 2007). Rani et al. (2011) recorded cost-benefit ratio as high as 5.51 with annual flower (Petunia hybrida) seed production under poplar. Jain and Singh (2000); Kumar et al. (2004) estimated the economic profitability of poplar 60 based agroforestry interventions higher than many other major crop rotations and stressed that better economics in agroforestry is due to the higher timber market value, which will always remain high due to huge gap of demand and supply for industrial wood. However, the slump in market during 2003-2005 was a setback to the poplar growers and now they remain vigilant for any such uncertainity (Saxena, 2004). Gupta et al. (2005) has analyzed the poplar market price trend, which was lowest during 2003 and recovered back during 2005 and recently touched the maximum of Rs. 12,000/- per ton, which has again attracted the attention of farmers. It is important to mention that the profitability of poplar based agroforestry is only accountable after the harvesting of poplar trees (5-8 yrs). Otherwise, the reduced yield of the crops under the tree canopy, lowers down the profitability margin than sole crop cultivation but the overall profitability on system basis after tree harvesting is substantially high than traditional crop cultivation (Gupta et al., 2005; Singh and Dhaliwal, 2005; Thind, 2005; Chauhan et al., 2010d; Chandra, 2011), thus, encourages the framers to invest in this sector and consider it a best performing low risk asset in near future (Sharma and Kumar, 2000b). Profitability analysis has been presented in different perspectives (farmers’ approach on the basis of available resources) by Chauhan et al. (2010b) and different practical models have been explained for their adoption by the respective farmers. The minimum support price for poplar timber declared by Haryana Forest Development Corporation (HFDC) is an encouraging incentive for the farmers and other adjoining states should also follow the same. Though the farmers are getting better prices in the open market but such policy initiatives in addition to permission for free harvesting, free interstate movement of timber, etc. boost the farmers for adoption of such remunerative venture. In near future, the carbon market can add to the profitability. Conclusion Poplar has become life line not only for the growers in the northwestern states but also the dependent industry. Poplar has very specifically been recommended as an option to diversify from the rice cultivation in northwestern states, which is resulting in lowering of water table in this region. In spite of best performing on-farm asset, not all the farmers could understand the long term profits well to invest in it. Today, certainly it is a low risk investment and farmers will continue growing till the prices are better than other agricultural options. Over the years, the interest of the farmers have increased the pressure on the research institutions to develop/import new clones, test new crop combination in ENVIS different geometry/land holdings/year of cultivation, replicate the success stories of the poplar growing pockets in other areas, etc. Resultantly, new clones have been recommended to replace the old ones (G3, D121, L34, G48, etc.), different crop combinations are under investigation and poplar has extended to new areas of Bihar state with a hope to transform economy of the farmers and the industry in that part of the country (Dhiman, 2010). However, it could not be extended southwards because it did not enter into dormancy during mild winters, thus, affected intercropping. Leaf shedding in poplar during winter is an added advantage for its integration with crops with minimum shade effect during vegetative growth phase of winter crops. Innovation and imaginations are certainly helpful in designing new systems. For achieving the full potential of poplar based agroforestry, still, there is need for fundamental understanding of how and why farmers are interested to make long term land use decisions. To make the agriculture in general and poplar based agroforestry systems in particular a profitable venture, it needs to align with the market/industry requirements. Standardization of the cultivation of clones most sought after by the industry is the key for keeping these systems alive, profitable and viable in future. Thus, by projecting the future scenario from the present perspective with respect to shade loving species, the intercropping of high value crops; i.e., flowers, vegetables, aromatic and medicinal plants, etc. with poplars are inevitable. There is immense possibility of extending poplar cultivation in the North-western states of the country to uplift the socio-economic status of the farmers besides meeting the industrial requirements. The system as such establishes synergy in sharing the vital resources; i.e., light, water and nutrients besides fixing significant carbon quantities both in wood and soil. Adequate care and proper management of plantations are essential to harness appropriate productivity of the poplar trees. The complete package of practices in terms of poplar cultivation have been developed for optimum income from the trees at the end of rotation period (Chandra, 1986; Jones and Lal, 1989; Lal, 1991), additionally other public-private organizations involved in research and extension are supporting the farmers with similar gesture. Still, there is ample gap as regards biophysical and socioeconomic processes in the system and needs extensive focused research. The agroforestry research, extension, human resource and infrastructure need to be strengthened, so that the benefits of resource conservation and environmental amelioration besides timber requirements are realized. The financial resources to strengthen the intensive research in the system through national and international collaboration will certainly meet the growing aspirations of the farmers in meeting the objectives of Forestry Bulletin, 12(1), 2012 diversification in traditional unsustainable crop rotations through agroforestry interventions. References Ajit; Das, D.K.; Chaturvedi, O.P.; Jabeen, N. and Dhyani, S.K. 2011. Predictive models for dry weight estimation of above and below ground biomass components of Populus deltoides in India: Development and comparative diagnosis. Biomass and Bioenergy, 35(3): 1145-1152. Aulakh, K.S. 2005. Crop diversification is a necessity: Paddy a drain on Punjab water resources. The Tribune, 25 February 2005. Ball, J.; Carle, J. and Lungo, A.D. 2005. Contribution of poplars and willows to sustainable forestry and rural development. Unasylva, 221: 3-9. Bangarwa, K.S. and Wuehlisch, G.V. 2009. Using exotic poplar in northern India for higher returns in agroforestry. Asia-Pacific Agroforestry News, 35: 3-5. Benbi, D.K.; Kiranbir Kaur; Toor, A.S.; Singh, Pritpal; Singh, Hargopal. 2012. Soil carbon pools under poplarbased agroforestry, rice-wheat, and maize-wheat cropping systems in semi-arid India. Nutrient Cycling and Agroecosystem, 92: 107-118. Brelivet, S. 2006. Wheat under the trees. South East NSW Private Forestry Newsletter, 4p. Burgess, P.J.; Incoll, L.D.; Corry, D.T.; Beaton, A. and Hart, B.J. 2004. Poplar (Populus spp) growth and crop yields in a silvoarable experiment at three lowland sites in England. Agroforestry Systems, 63(2): 157169. Burgess, P.J.; Seymour, I.; Incoll, L.D.; Corry, D.T.; Hart, B. and Beaton, A. 2000. The application of silvoarable agroforestry in the UK. Aspects of Applied Biology, 62: 269-276. Burgess, P.J.; Stephens, W.; Anderson, G. and Durston, J. 1996. Water use by a poplar wheat agroforestry system. Aspects of Applied Biology, 44: 1-8. Calstelloni, E. and Prevoster, V. 1961. Experimental contribution to the study concerning the relation between poplars grown on field borders and some agricultural crops. In: Congress of the International Union of Forestry Research Organization, 13th Vienna, 10-16 Septermber 1961. Papers. Rome, FAO. Chandra, J.P. 1986. Poplar - A cash crop for north Indian farmers. Indian Forester, 112: 698-710. Chandra, J.P. 2001. Scope of poplar cultivation. Indian Forester, 127(1): 51-60. 61 Chandra, J.P. 2011. Development of poplar based agroforestry system. Indian Journal of Ecology, 38: 11-14. Chaudhry, A.Q.; Khan, G.S.; Siddiqui, M.T.; Akhtar, M. and Aslam, Z. 2003. Effect of arable crops on the growth of poplar (Populus deltoides) tree in agroforestry systems. Pakistan Journal of Agricultural Sciences, 40(1-2): 82-85. Chauhan, H.S. 2000. Performance of poplar (Populus deltoides) based agroforestry system using aromatic crops. Indian Journal of Agroforestry, 2: 17-21. Chauhan, S.K. and Chauhan, R. 2009. Exploring carbon sequestration in poplar-wheat based integrated cropping system. Asia-Pacific Agroforestry News, 35: 9-10. Chauhan, S.K. and Mahey, R.K. 2008. Poplar cultivation. Ludhiana, PAU. 36p. Chauhan, S.K. and Mangat, P.S. 2006. Poplar based agroforestry is ideal for Punjab, India. Asia-Pacific Agroforestry News, 28: 7-8. Chauhan, S.K.; Beri, V. and Sharma, S.C. 2007. Studies on carbon sequestration under different farm/ agroforestry interventions. Final report of Adhoc Research Project submitted to ICAR New Delhi. Ludhiana, Department of Forestry and Natural Resources, PAU. 131p. Chauhan, S.K.; Brar, M.S. and Sharma, R. 2012a. Performance of poplar (Populus deltoides Bartr.) and its effect on wheat yield under agroforestry system in irrigated agro-ecosystem, India. Caspian Journal of Environmental Sciences, 10: 53-60. Chauhan, S.K.; Chauhan, R. and Saralch, H.S. 2008. Diversity of poplar (Populus deltoides) clones in India. In: Kundu, S.S.; Chaturvedi, O.P.; Dagar, J.C. and Sirohi, S.K. Eds. Environment, agroforestry and livestock management. Lucknow, International Book Distributors. pp. 175-188. Chauhan, S.K.; Dhillon, W.S. and Nighat Jabeen. 2011a. Analyzing the performance of Colocasia esculenta in poplar based agroforestry system. Asia-Pacific Agroforestry News, 39: 9-10. Chauhan, S.K.; Dhillon, W.S.; Singh, N.; Sharma, R. 2012c. Physiological behaviour and yield evaluation of agronomic crops under agri-horti-silviculture system. International Journal of Plant Research. [Accepted] Chauhan, S.K.; Dhiman, R.C.; Nangole, E.; Lamond, Genevieve; Dubas, J.; Matela, R.; Niedzielski, M. and Lewis, T. 2010d. Profitability of short rotation forestry from the 62 farmer’s perspective. Report submitted to European Commission. 122p. Chauhan, S.K.; Gupta, N.; Ritu; Yadav, S. and Chauhan, R. 2009b. Biomass and carbon allocation in different parts of agroforestry tree species. Indian Forester, 135(7): 981-993. Chauhan, S.K.; Gupta, N.; Walia, R.; Yadav, S.; Chauhan, R. and Mangat, P.S. 2011b. Biomass and carbon sequestration potential of poplar-wheat intercropping system in irrigated agro-ecosystem in India. Journal of Agricultural Science and Technology A, 1(4): 575-586. Chauhan, S.K.; Nanda, R.K. and Brar, M.S. 2009a. Adoption of poplar based agroforestry as an approach for diversified agriculture in Punjab. Indian Forester, 135(5): 671-677. Chauhan, S.K.; Nanda, R.K. and Gill, S.S. 2005. Diversification of traditional agricultural rotation through poplar based agroforestry in Indian Punjab. In: Commonwealth Forestry Congress on Forestry’s Contribution to Poverty Reduction, 17th, Colombo, 28 February-5 March 2005. Proceedings. p. 15. Chauhan, S.K.; Rani, S. and Kumar, R. 2010c. Asessing the economic viability of flower seed production under poplar trees. Asia-Pacific Agroforestry News, 37: 6-7. Chauhan, S.K.; Sharma, S.C.; Beri, V.; Ritu; Yadav, S. and Gupta, N. 2010b. Yield and carbon sequestration potential of wheat (Triticum aestivum) and poplar (Populus deltoides) based agri-silvicultural system. Indian Journal of Agricultural Sciences, 80(2): 129-135. Chauhan, S.K.; Sharma, S.C.; Chauhan, R.; Gupta, N. and Ritu. 2010a. Accounting poplar and wheat productivity for carbon sequestration agri-silvicultural system. Indian Forester, 136(9): 1174-1182. Chauhan, S.K.; Sharma, S.C.; Sharma, R.; Gupta, N. and Ritu. 2012b. Evaluation of poplar (Populus deltoides Bartr.) boundary plantation based agri-silvicultural system for paddy-wheat yield and carbon storage. International Journal of Agriculture and Forestery. [Accepted]. Chauhan, V.K. and Dhiman, R.C. 2002. Evaluation of wheat (Triticum aestivum) under different spacing of poplar (Populus deltoides) in lower western Himalayas. Indian Journal of Agricultural Sciences, 72: 470473. Chauhan, V.K. and Dhiman, R.C. 2007. Atmospheric humidity and air temperature studies in wheat-poplar based agroforestry system. Indian Forester, 133(1): 73-78. ENVIS Chauhan, V.K.; Joshi, A.K. and Dholta, V.K. 2008. Performance of maize (Zea mays L.) varieties under different spacing of poplar (Populus deltoides Marsh.) in lower western Himalayas. Indian Forester, 134(12): 1603-1611. Chaturvedi, A.N. 1983. Poplar for farm forestry in Uttar Pradesh. Indian Forester, 109: 661-664. Chaturvedi, A.N. 1992. Optimum rotation of harvest for poplars in farmlands under agroforestry. Indian Forester, 118(2): 81-88. Christersson, L. 2010 Wood production potential in poplar plantations in Sweden. Biomass and Bioenergy, 34(9): 1289-1299. Current, D.; Lutz, E. and Scherr, S. 1995. Costs, benefits and farmers adoption of agroforestry. Project experience in central America and the Carribbean. Enviornmental Paper No. 14. Washington, DC, The World Bank. Dalal, S.S. and Trigotra, R.C. 1983. Experience in poplar cultivation outside forests. Indian Forester, 109(10): 726-736. Das, D.K. and Chaturvedi, O.P. 2005. Structure and function of Populus deltoides agroforestry systems in eastern India. 2. Nutrient dynamics. Agroforestry Systems, 65(3): 223-230. Dhadwal, K.S. and Narain, P. 1988. Agroforestry for soil productivity and conservation - A review. Indian Journal of Soil Conservation, 16: 38-48. Dhillon, A.; Sangwan, V.; Malik, D.P. and Lubach, M.S. 2001. An economic analysis of poplar cultivation. Indian Forester, 127(1): 86-90. Dhillon, G.P.S.; Dhanda, R.S.; Gill, R.I.S. and Singh, Pritpal. 2011. Estimation of over-and under-size merchantable timber volume of Populus deltoides Bartr. Indian Forester, 137(3): 356-362. Dhillon, W.S.; Chauhan, S.K. and Jabeen, N. 2011. Microclimatic amelioration and yield potential in hortisilvicultural system. Indian Journal of Ecology, 38: 124-128. Dhillon, W.S.; Chauhan, S.K. and Singh, N. 2009. Physiology and yield of turmeric under poplar canopy. Asia-Pacific Agroforestry News, 35: 5-6. Dhillon, W.S.; Chauhan, S.K.; Jabeen, N.; Singh, C. and Singh, N. 2012. Growth performance of inter-cropping system components and nutrient status of soil under horti-silvicultural system. Accepted in International Journal of Environmental Resourcse Research. Dhillon, W.S.; Srinidhi, H.V. and Chauhan, S.K. 2007. Ecophysiology of crops grown under poplar tree Forestry Bulletin, 12(1), 2012 canopy. Asia-Pacific Agroforestry News, 30: 1112. Dhillon, W.S.; Srinidhi, H.V.; Chauhan, S.K.; Singh, C.; Singh, N. and Jabeen, N. 2010. Micro-envoriment and physiology of turmeric cultivated under poplar tree canopy. Indian Journal of Agroforestery, 12(2): 2337. Dhiman, R.C. 2009. Carbon footprint of planted poplar in India 2009. ENVIS Forestry Bulletin, 9(2): 70-81. Dhiman, R.C. 2010. Growing poplar in Bihar: A new hope for farmers and the wood based industry. Ply Gazette. pp. 87-91. Dhiman, R.C. 2012. Diagnosis of intercrops in poplar based agroforestry in India. Indian Forester, (Accepted) Dhiman, R.C. and Gandhi, J.N. 2010. Varietal differences in onion and garlic yield when grown with and without mulch in three years old poplar plantation. Indian Journal of Agroforestry, 12(1): 40-45. Dickman, D.I. and Stuart, W.K. 1983. The culture of poplars in Eastern North America. Michigan, Department of Forestry, Michigan State University. Dogra, A.S.; Upadhayay, A.; Sharma, S.C. and Chauhan, S.K. 2007. Potential of agroforestry as a land use option in Punjab, India. Indian Forester, 133(11): 14371448. Durai, M.V.; Ralhan, P.K.; Sharma, R.; Singh, A. and Chauhan, S. 2009. Nutrient harvest through pruned material and whole tree in Populus deltoides based agrisilviculture systems in central Punjab. Indian Forester, 135(12): 1716-1723. Dwivedi, R.P.; Kareemulla, K.; Singh, R.; Rizvi, R.H. and Chauhan, J. 2007. Socio-economic analysis of agroforestry system in western Uttar Pradesh. Indian Research Journal of Extension Education, 7: 18-22. Gandhi, J.N. and Dhiman, R.C. 2010. Performance of wheat intercropped under different tree spacings of poplar (Populus deltoides Marsh) plantation. Indian Journal of Agroforestry, 12(2): 28-31. Gandhi, J.N. and Joshi, B.C. 2002. Poplar based agroforestry and planting stock availability. In: Sanjeev, K.; Chauhan, R. and Gill, S.S. Eds. Tree-crop interface. Ludhiana, Department of Forestry and Natural Resources, PAU. pp. 157-161. Gautam, S.K. and Thapa, H.B. 2007. Volume equation of Populus deltoides plantation in western Terai of Nepal. Banko Janakari, 17: 70-73. Gera, M.; Mohan, G.; Bisht, N.S. and Gera, N. 2006. Carbon sequestration potential under agroforestry in 63 Roopnagar district of Punjab. Indian Forester, 132(5): 543-555. Gera, M.; Mohan, G.; Bisht, N.S. and Gera, N. 2011. Carbon sequestration potential of agroforestry under CDM in Punjab state of India. Indian Journal of Forestry, 34(1): 1-10. Gill, B.S.; Singh, A.; Singh, D. and Gandhi, N. 2008. Studies on intercropping of medicinal, aromatic and spice crops in poplar plantation. Indian Journal of Agronomy, 53: 295-298. Gill, R.I.S.; Singh, B. and Kaur, N. 2009. Productivity and nutrient uptake of newly released wheat varieties at different sowing times under poplar plantation in north-western India. Agroforestry Systems, 76(3): 579-590. Gupta, D.C.; Zomer, R.J. and Bossio, D.A. 2005. Poplar agroforestry in India: Trends and impacts. IWMI Project Report. Colombo, International Water Management Institute. 57p. Gupta, M.K. and Pandey, R. 2008. Soil organic carbon pool under different plantations in some districts of Uttrakhand and Haryana. Indian Journal of Forestry, 31(3): 369-374. Gupta, N.; Kukal, S.S. and Singh, P. 2006. Soil erodibility in relation to poplar based agroforestry system in north western India. International Journal of Agriculture and Biology, 8: 859-861. Gupta, N.; Kukal, S.S.; Bawa, S.S. and Dhaliwal, G.S. 2009. Soil organic carbon and aggregation under poplar based agroforestry system in relation to tree age and soil type. Agroforestry Systems, 76(1): 27-35. Henderson, D.E. and Jose, S. 2010. Biomass production potential of three short rotation woody crop species under varing nitrogen and water availability. Agroforestry Systems, 80(2): 259-273. Hymavathi, H.N.; Kandya, A.K. and Patel, L.P. 2010. Beneficial effects of multiple plantation pattern in agroforestry systems. Indian Forester, 136(4): 465-475. ICAR (Indian Council of Agricultural Research). 2010. Diversification in traditional agriculture through horti-silvicultural system. Adhoc Project Report. New Delhi, ICAR. 85p. ICFRE (Indian Council of Forestry Educaton and Research). 2012. Country report on poplars and willows 20082012. Dehradun, ICFRE. 61p. Jain, S.K. and Singh, P. 2000. Economic analysis of industrial agroforestr: Poplar (Populus deltoides) in Uttar Pradesh (India). Agroforestry Systems, 49(3): 255273. 64 Jaswal, S.C.; Mishra, V.K. and Verma, K.S. 1993. Intercropping ginger and turmeric with poplar (Populus deltoides ‘G-3’ March). Agroforestry Systems, 22(2): 111-117. Jha, K.K. and Gupta, C. 1991. Intercropping of medicinal plants with poplar and their phenology. Indian Forester, 117(7): 535-544. Jones, N. and Lal, P. 1989. Commercial poplar planting in India under agroforestry system. Commonwealth Forestry Review, 68: 19-26. Jose, S. 2009. Agroforestry for ecosystem services and environmental benefits: An overview. Agroforestry Systems, 76(1): 1-15. Joshi, B.C. 1996. Poplar cultivation under agroforestry. In: Session of the International Poplar Commission, 20th, Budapest, 1-4 October 1996. Environmental and social issues in poplar and willow cultivation and utilization: Proceedings. pp. 409-423. Kaur, A. and Rao, P.B. 1998. Effect of tree leaf leachates on germination of certain varieties of wheat. Indian Journal of Environmental Sciences, 2: 29-34. Kaushal, R.; Verma, K.S. and Singh, K.N. 2003. Effect of Grewia optiva and Populus deltoides leachates on field crops. Allelopathy Journal, 11: 229-234. Kaushal, R.; Verma, K.S. and Singh, K.N. 2005. Seasonal dynamics and role of substrate quality in leaf litter decomposition of different agroforestry tree species. Indian Journal of Agroforestry, 7(1): 44-50. Khan, G.S. and Chaudhry, A.Q. 2007. Effect of spacing and plant density on the growth of poplar (Populus deltoides) trees under agroforestry system. Pakistan Journal of Agricultural Sciences, 44(2): 321-327. Kohli, R.K.; Singh, H.P. and Batish, D.R. 1997. Phytotoxicity potential of Populus deltoides Bartr. ex Marsh I. Comparative contribution of different parts. Indian Journal of Forestry, 20(3): 300-304. Kumar, D.; Kumar, P. and Kumar, P. 2001. Leaf fall in poplar and its impact on wheat intercrop. Indian Forester, 127(2): 187-190. Kumar, R.; Gupta, P.K. and Gulati, A. 2004. Viable agroforestry models and their economics in Yamunanagar district of Haryana and Haridwar district of Uttranchal. Indian Forester, 130(2): 131-148. Lal, P. 1991. Improved package of practices for poplar under agroforestry. Indian Forester, 117(3): 168-177. Lal, R. 2004. Soil carbon sequestration impacts on global climate change and food security. Science, 304: 16231627. ENVIS Mathur, R.S. and Sharma, K.K. 1983a. Poplar in agroforestry. In: National Workshop on Agroforestry, Karnal, 2123 July 1983. Proceedings. Mathur, R.S. and Sharma, K.K. 1983b. Poplars in India. Indian Forester, 109: 591-605. Mishra, A.; Agrawal, R. and Swamy, S.L. 2006. Productivity of soybean and wheat under five promising clones of Populus deltoides in agrisilviculture system. Plant Archives, 6(2): 567-571. Mishra, V.K. and Gupta, N.K. 1993. Effect of spacing on stem and crown development in cottonwood (Populus deltoides Bartr.). Indian Forester, 119(9): 732-737. Montagnini, F. and Nair, P.K.R. 2004. Carbon sequestration: An underexploited environmental benefit of agroforestry systems. Agroforestry Systems, 61-62(1): 281-295. Nair, P.K.R. 1991. State-of -the-art of agroforestry systems. Forest Ecology and Management, 45(1-4): 5-29. Nair, P.K.R.; Nair, V.D.; Mohan, B.K. and Showalter, J.M. 2010. Carbon sequestration in agroforestry systems. Advances in Agronomy 108:237-307. Nandal, D.P.S. and Dhillon, A. 2007. Allelopathic effect of poplar (Populus deltoides Bartr. ex Marsh): An assessment on the response of wheat varieties under laboratory and field conditions. Indian Journal of Agroforestry, 9(2): 125-127. Newaj, R. and Dhyani, S.K. 2008. Agroforestry systems for carbon sequestration: Present status and scope. Indian Journal of Agroforestry, 10(1): 1-9. Newman, S.M. 1997. Poplar agroforestry in India. Forest Ecology and Management, 90(1): 13- 17. Nouman, W.; Khan, G.S.; Siddiqui, M.T. and Riaz, A. 2008. Farmer’s attitude towards agroforestry in District Faislabad. Pakistan Journal of Agricultural Sciences, 45(1): 60-64. Pal, R.; Melkania, U. and Dhiman, R.C. 2009. Inter-clonal variation in carbon pool of Populus deltoides Bartr. Indian Forester, 135(9): 1209-1216. Pande, P.K. 2011. Variation in wood properties and growth in some clones of Populus deltoides Bartr. ex Marsh. American Journal of Plant Sciences, 2(5): 644-649. Pande, P.K. and Dhiman, R.C. 2011. Performance and variability patterns in wood properties and growth traits in the parents, F1 and F2 generation hybrid clones of Populus deltoides. Journal of Forestry Research, 22(3): 379-385. Pandey, D.N. 2002. Carbon sequestration in agroforestry systems. Climate Policy, 2(4): 367-377. Pandey, D.N. 2007. Multifunctional agroforestry systems in India. Current Science, 92: 455-463. Forestry Bulletin, 12(1), 2012 Pannu, N.S. and Dhillon, M.S. 1999. Production potential of poplar-wheat based agroforestry system in relation to wheat varieties and their dates of sowing. Indian Journal of Forestry, 22(3): 257-262. Pant, K.S.; Mishra, V.K.; Sanwal, C.S. and Dinssa, K.U. 2010. Effect of nitrogen and poplar spacing on yield and nutrient nutrients of taro (Colocasia esculenta L.). Indian Journal of Agroforestry, 12: 18-22. Pearson, C.H.; Halvorson, A.D.; Moench, R.D. and Hammon, R.W. 2010. Production of hybrid poplar under shortterm, intensive culture in Western Colorado. Industrial Crops and Products, 31: 492-498. Pendleton, J.W. and Weibel, R.O. 1965. Shading studies on winter wheat. Agronomy Journal, 57(3): 292293. Puri, S. and Bangarwa, K.S. 1992. Effects of trees on the yield of irrigated wheat crop in semi arid regions. Agroforestry Systems, 20(3): 217-227. Puri, S. and Sharma, A. 2002. Productivity of wheat under a Populus deltoides agroforestry system in the southeast of central India. Indian Forester, 128(12): 13191326. Puri, S.; Singh, V.; Bhushan, B. and Singh, S. 1994. Biomass production and distribution of roots in three stands of Populus deltoides. Forest Ecology and Management, 65(2-3): 135-147. Raj, A.J.; Lal, S.B.; Daniel, S. and Gowda, V. 2010. Intercropping of lemon grass with poplar (Populus deltoides Bartr ex Marsh) in eastern Uttar Pradesh. Indian Journal of Agroforestry, 12(1): 13-17. Ralhan, P.K.; Singh, A. and Dhanda, R.S. 1992. Performance of wheat as inter- crop under poplar (Populus deltoides Bartr.) plantation in Punjab. Agroforestry Systems, 19(3): 217-222. Ranasinghe, O.M.S.H.K. and Mayhead, G.J. 1990. The effect of intercropping Populus ‘RAP’ with beans. Forestry, 63(3): 271-277. Rani, S. 2009. valuation of winter flowering annuals for seed production under poplar based agroforestry system. M.Sc. thesis. PAU, Ludhiana. 69p. Rani, S.; Chauhan, S.K.; Kumar, R. and Dhatt, K.K. 2011. Bioeconomic appraisal of flowering annuals for seed production under poplar (Populus deltoides) based agroforestry system. Tropical Agricultural Research, 22: 125-133. Rivest, D.; Cogliastro, A.; Vanasse, A. and Olivier, A. 2009. Production of soybean associated with different hybrid poplar clones in a tree-based intercropping system in southwestern Quebec, Canada. 65 Agriculture, Ecosystems and Environment, 131: 5160. Rizvi, R.H.; Dhyani, S.K.; Yadav, R.S.; Singh, Ramesh. 2011. Biomass production and carbon stock of poplar agroforestry systems in Yamunanagar and Saharanpur districts of northwestern India. Current Science, 100: 736-742. Rizvi, R.H. and Khare, D. 2006. Prediction models for timber weight of Populus deltoides planted on farmlands in Haryana. Indian Journal of Agroforestry, 8(1): 77-85. Rizvi, R.H.; Khare, D. and Dhillon, R.S. 2008a. Heightdiameter model for poplar (Populus deltoides) grown in agroforestry systems in Haryana. Range Management and Agroforestry, 29: 1922. Rizvi, R.H.; Khare, D. and Dhillon, R.S. 2008b. Statistical models for aboveground biomass of Populus deltoides planted in agroforestry in Haryana. Tropical Ecology, 49(1): 35-42. Rizvi, R.H.; Khare, D. and Handa, A.K. 2010. Construction and validation of models for timber volume of poplar (Populus deltoides) planted in agroforestry in Haryana. Indian Journal of Agricultural Sciences, 80(9): 841-844. Sanchez, P.A. 1995. Science in agroforestry. Agroforestry Systems, 30(1-2): 5-55 Saxena, V. 2004. Greening the Indian state of Haryana with trees. Asia-Pacific Agroforestry News, 23: 910. Schoeneberger, M.M. 2009. Agroforestry: Working trees for sequestering carbon on agricultural lands. Agroforestry Systems, 75(1): 27-37. Schoreder, P. 1994. Carbon storage benefits of agroforestry system. Agroforestry Systems, 27(1): 89-97. Sharma, K.K. 1996. Agroforestry in farming systems development. Indian Forester, 122(7): 547-559. Sharma, N.K.; Samra, J.S. and Singh, H.P. 2000. Effect of aqueous extract of Populus deltoides M. on germination and seedling growth of wheat. Alleopathy Journal, 7(1): 56-68. Sharma, N.K.; Samra, J.S. and Singh, H.P. 2001. Influence of boundary plantation of poplar (Populus deltoides M.) on soil-water use and water use efficiency of wheat. Agricultural Water Management, 51(3): 173185. Sharma, S.C.; Dogra, A.S.; Upadhayay, A. and Chahal, G.S. 2007. Carbon stock and productivity assessment of 66 Populus deltoides Bartr. ex Marsh in Punjab. Indian Forester, 133: 8-16. Sharma, S.K.; Chauhan, S.K. and Handa, A.K. 1998. Wheat based agroforestry system under rainfed ecosystem. Range Management and Agroforestry, 19: 43-48. Sharma, U. and Sharma, V. 2011. Soil as a sink for carbon sequestration: how agroforestry can help? Indian Journal of Agroforestry, 13(1): 65-77. Sharma, V.P. and Kumar, A. 2000a. Effects and financial performance of poplar-based agroforestry systems in the north-western region of India. Agricultural Economics Research Review, 13(2): 123-137. Sharma, V.P. and Kumar, A. 2000b. Factors influencing adoption of agroforestry programme: A case study from North-West India. Indian Journal of Agricultural Economics, 55(3): 500-510. Sheikh, M.I.; Cheema, A. and Raza-Ul-Haq. 1983. Effect of poplars on the yield of wheat at Changa Manga irrigated plantation. Pakistan Journal of Forestry, 33: 201-207. Singh, A.; Dhanda, R.S. and Ralhan, P.K. 1993. Performance of wheat varieties under poplar (Populus deltoides) plantations in Punjab (India). Agroforestry Systems, 22(1): 83-86. Singh, B. and Sharma, K.N. 2007. Tree growth and nutrient status of soil in a poplar (Populus deltoides Bartr.) based agroforestry system in Punjab, India. Agroforestry Systems, 70(2): 125-134. Singh, G.B. 1999. Agroforestry research in India – issues and strategies. Indian Journal of Agroforestry, 1(1): 114. Singh, H.P.; Kohli, R.K. and Batish, D.R. 1998. Effect of poplar (Populus deltoides) shelterbelt on the growth and yield of wheat in Punjab, India. Agroforestry Systems, 40(2): 207-213. Singh, H.P.; Kohli, R.K. and Batish, D.R. 1999. Impact of Populus deltoides and Dalbergia sissoo shelterbelts on wheat-a comparative study. International Tree Crops Journal, 10: 51-60. Singh, H.P.; Kohli, R.K. and Batish, D.R. 2001. Allelopathic interference of Populus deltoides with some winter season crops. Agronomie, 21: 139-146. Singh, K.; Ram, P.; Singh, A.K. and Hussain, A. 1988. Poplar (Populus deltoides Bartram ex Marshall) in forest and agroforestry systems. Indian Forester, 114(11): 814-818. Singh, K.; Singh, V.; Hussain, A. and Kothari, S.K. 1990. Aromatic plants as efficient intercrops under poplars ENVIS (Populus deltoides Bartr. ex Marsh). Indian Forester, 116(3): 189-193. Singh, P. and Lodhiyal, L.S. 2009. Bioamss and carbon allocation in 8 year old poplar (Populus deltoides Marsh) plantation in Tarai agroforestry systems of central Himalaya, India. New York Science Journal, 2(6): 49-53. Singh, S. and Dhaliwal, H.S. 2005. An economic analysis of poplar based agroforestry systems in Punjab, India. Indian Journal of Forestry, 28: 381-388. Singh, V.N. and Upadhyay, A.K. 2001. Volume tables for G48 and D121 clones of Populus deltoides for the Tarai and Bhabhar regin of Uttaranchal. Indian Forester, 127(1): 21-29. Srinidhi, H.V.; Chauhan, S.K. and Sharma, S.C. 2007. SWOT analysis of Indian agroforestry. Indian Journal of Agroforestry, 9: 1-11. Tandon, V.N.; Pandey, M.C.; Rawat, H.S. and Sharma, D.C. 1991. Organic productivity and mineral cycling in plantations of Populus deltoides in Tarai region of Uttar Pradesh. Indian Forester, 117(8): 596-608. Thind, H.S. 2005. Poplar based agroforestry system: A sustainable alternative to rice wheat production system. In: Chauhan, S.K.; Gill, S.S.; Sharma, S.C. Forestry Bulletin, 12(1), 2012 and Chauhan, R. Eds. Agroforestry in 21st Century. Udaipur, Agrotech Publishing. pp. 56-62. Tiwari, K.M. 1968. Prospects of poplar plantation in Uttar Pradesh. Indian Forester, 94(2): 163-168. Verma, A. 2008. Evaluation of growth behavior of Populus deltoides Marsh. clones under farm forestry. M.Sc. thesis. PAU, Ludhiana. Yadav, A.K. 2010. Carbon sequestration: Unexploited environmental benefits of Tarai agroforestry systems. Report and Opinion, 2(11): 35-41. Zabek, L.M. and Prescott, C.E. 2006. Biomass equations and carbon content of above ground leafless biomass of hybrid poplar in coastal British Columbia. Forest Ecology and Management, 223(1-3): 291-302. Zeng De-Hui; Rong Mao; Scott X Chang; Lu-Jun Li; Dan Yang. 2010. Carbon mineralization of tree leaf litter and crop residues from poplar-based agroforestry systems in Northeast China: A laboratory study. Applied Soil Ecology, 44: 133-137. Zomer, R.J.; Bossio, D.A.; Trabucco, A.; Yuanjie, L.; Gupta, D.C. and Singh, V.P. 2007. Trees and water: Small holder agroforestry on irrigated lands in Northern India. IWMI Research Report No.122. Colombo, International Water Management Institute. 47p. z 67 Poplar Culture on Farmland: Farmer’s Experience from Uttar Pradesh Nikki Pilania Chaudhary and Gaurav Chaudhary Chaudhary Farm, Pilibhit, Uttar Pradesh - 262 305 Introduction T Poplar based agroforestry is not only economically very attractive but also beneficial to environment 68 he increasing pressure of growing population and demand for food and wood had resulted in conversion of large areas of forests to agriculture, industrial and urban development. This further led to scarcity of fuel wood, timber for construction and wood for many commercial uses. In order to save forests and trees for an important role that they play in climate change mitigation, prevention of soil erosion, etc., measures have been taken by several countries to conserve them and this has further reduced the supply of wood. The shortage of supply of timber is likely to increase in India making it difficult for the country to meet its requirements from both domestic and international front. Hence, partial solution to the above problems could be to increase area under tree cover by either growing trees on farm boundaries or by integrating them with agricultural crops on farmland. In other words, there is a need for wide scale adoption of agroforestry as land use. Agroforestry is a land use system in which trees are grown with agricultural crops. The agroforestry, which has gained wide popularity in northwestern India, is cultivation of poplar trees for timber along with other crops like wheat, sugarcane, turmeric, etc. Poplar is a major agroforestry tree species grown in Punjab, Haryana, western Uttar Pradesh (U.P.) and Uttarakhand due to its fast growth, profitable returns and high industrial demand. Poplar is one of the world’s fastest growing industrial softwood and can be harvested at short rotations depending on the end use of its tree components. Its wood is light, homogenous, odorless and is excellent for manufacturing matches, pencils, plywood, light constructional timber, paper, and packaging cases. Poplar is deciduous in nature and therefore it adds leaf litter during winters thereby adding fertility to the soil. Its leaf shedding characteristic allows intercrops to be grown in winters. Wheat is the most preferred winter crop grown with poplar. According to Hara (2006), agroforestry has contributed immensely to society by way of providing good returns to farmers, supported wood industry thereby providing employment to millions, has given cheaper wood products to consumers and reduced India’s dependence on wood imports. ENVIS Poplar Based Agroforestry (PBA) in the Terai Plains of Western Uttar Pradesh and Uttarakhand As early as 1970s progressive farmers in the Terai region of U.P. started planting poplar with intercrops (Chandra, 2001). Since then there has been rapid adoption of poplar based agroforestry (PBA) in this region. The system adopted here is of taking sugarcane as intercrop for first two years followed by wheat as winter crop until the harvest of poplar trees. Wood based industry in the region has been depended on the state forest departments for raw material until the late 1970s. Later on, the green felling was banned in state forests which meant that wood based industry had to go to farmers for their raw material needs (Chandra, 2003). In 1976, an extensive publicity campaign was initiated by WIMCO to promote poplar cultivation. It decided to give farmers genetically superior quality poplar plants to grow, for them (Hara, 2006). WIMCO distributed 126,000 seedlings of poplar free of cost to farmers in the year 1983 in northwestern India. In 1984, WIMCO together with NABARD worked out a poplar refinance project. As per the project: 1. WIMCO supplied ETPs to the farmers. 2. It also transported the ETPs free of cost to the farmer’s field. 3. It provided technical know-how to farmers for the entire growth period of the trees. 4. Damaged ETPs were replaced by WIMCO in the farmers’ fields in the first two years. 5. Insurance cover for tree damage was arranged by the company. 6. WIMCO paid Rs. 500 or market price whichever was higher once the trees met the requisite parameters (during the first phase of the project period). Extensive work done by WIMCO led to emergence of poplar based agroforestry as a major farming practice in North India which has made great strides in India in the last three decades. Poplar Based Agroforestry at Our Farm Chaudhary Farm is one of the leading well managed farms of the locality. The farm has all ingredients of modern agriculture that include intensive and mechanized farming with heavy inputs, farm site for testing and growing latest varieties in association with the leading agricultural university of the locality, organic farming with vermicompost and farmyard Forestry Bulletin, 12(1), 2012 manure, diverse land use practices of horticultural crops like mango, litchi, guava; and agroforestry with poplar, eucalypts, teak, kadam, etc. The farm is located in Majhola belt of Pilibhit District of northern Uttar Pradesh. The locality falls in the Terai region with water table close to surface. The soils are loamy to clayey loam. It is one of the agriculturally productive belt of northern India known to grow wheat-paddy crop combination and sugarcane as annual crop. We at Chaudhary Farm have been planting poplar since 1987 and there is no denying that a well-managed farm gives economic returns much more than the conventional crops and this will be shown by comparison that we have made through our calculations. Our poplar plantations have been giving returns in excess of Rs. one hundred thousand per acre per annum consistently since last 3-4 yrs, whereas paddy-wheat rotation gives us a return of about Rs. 25,000 per acre per annum. Clearly, returns from poplar are four times higher than that of paddy-wheat rotation. This is studied in detail in later sections. There are other benefits of poplar based agroforestry over paddy-wheat rotation. We have found that the soil health improves under poplar plantations, whereas repeated practice of rice-wheat rotation depletes the soil health. The crop yields taken after the harvest of poplar have been much higher than those taken on plots where poplar was not planted. We have 12,000 poplar trees of high genetic quality planted at our farm. Spacing pattern of 4m x 5m, 4m x 4m and 7m x 3m are being followed and plantations are harvested in seven years yielding about 1,000 q of timber per acre on harvest. We first came to know of poplar from WIMCO. In the face of acute shortage of timber in late 1970s WIMCO took steps to promote poplar based agroforestry on commercial scale in the Terai districts of U.P., many of which are now part of Uttarakhand. High yielding clones of poplar were introduced and farmers were encouraged to plant them. Poplar was planted at our farm for the first time in the year 1987. We purchased 800 ETPs of D-121 clone from WIMCO at buy back arrangement and we were promised Rs. 500 per tree after 8 years provided certain parameters specified by WIMCO were met. The important parameter was that the trees should attain a girth size of 90 cm at a height of four and a half feet from ground level. The supervisors from WIMCO prescribed farmers the standard package of practices to be followed for the maintenance of poplar plantations and the farmers who didn’t comply with the right techniques and failed to achieve the expected girth size were not paid the full amount. 69 Once we purchased poplar seedlings from WIMCO, supervisors used to visit our farm every 15 days to see the progress of our poplar and tell us how and what can be done to grow poplar successfully. We were updated with all the latest techniques of managing these trees. Because of WIMCO’s support, timely guidance and advice we have been able to raise good plantations. Hence, WIMCO’s role has been immense in enabling us to earn remunerative returns from PBA. It has played a significant role in popularizing poplar among farmers and is largely responsible for the adoption of PBA in north-western India. D-121 was the first variety that we planted on our farm. This variety had a strong root system and lodging was little, however, its growth was slow. Then we shifted to G-3 clone. It gave very good volume of wood, grew fast and tapering was less. However, after few years the clone became susceptible to leaf spot disease (which caused premature defoliation in case of heavy attack) and this disease was difficult to control through chemical sprays, WIMCO stopped producing this variety and came up with new disease resistant clones. L-49 was another clone that we planted on our farm. It grew very fast and gave very good volume of timber in a shorter period but had a weak root system. Hence, damage due to winds was high. Once, 50 per cent trees of a block of L-49 clone were lodged in the winds and rains in September. This variety was also phased out from our farm. Then we shifted to clones like Kranti, G-48, S7C8 and S7C15. G-48 proved to be the most successful variety on our farm. Presently, we are planting new varieties developed by WIMCO seedlings - WIMCO-39, WIMCO-81 and WIMCO-110 and these are showing promising results in clay loam and clay type soil of our farm. Our Package of Practices Our raising of poplar plantations involves intensive investment and care in plant nutrition, plant protection, pruning, irrigation and other aspects of plant management to attain high rates of timber growth. We have been planting 200 to 250 trees per acre. High quality poplar ETPs purchased from WIMCO Ltd. are planted in January and sugarcane is sown as intercrop in first week of February. In first two years sugarcane is grown and after the ratoon has been harvested, wheat is taken in winter until the harvest of poplar. ETPs are lifted during the last week of December and on their receipt on the farm site these are immediately placed horizontally in pits filled with fresh water to prevent dehydration and then the transplanting begins in the first 70 week of January. We store ETPs in fresh water for a minimum of 3 days. ETPs can be safely stored under fresh water for 10 to 12 days before transplanting. Pretreatment of ETPs All thick long and damaged roots of ETPs are pruned. Those thick roots that are likely to interfere with normal placing of ETPs in the pits are trimmed. All small, fine roots are left untouched. ETPs are then treated with an insecticide and a systemic fungicide by dipping the roots in the solution containing chlorpyrifos 20 per cent EC (insecticide) and carbendazim 50 per cent WP (fungicide). For every 100 ETPs, a solution of 100 l of water mixed with 200 ml of chlorpyrifos and 200 g carbendazim is prepared. These ETPs are kept for about 10 minutes in this solution. Transplanting of ETPs into Pits About one meter deep pits are dug with augurs having a diameter of 15 cms. The ETP is then placed vertically into the pit which is then filled with the mixture of top soil, 5 kg. FYM, 25 g MOP, 200 g SSP, 25 g micronutrients (zinc, iron, copper, etc.) and Trichoderma. One month before transplanting, we mix farmyard manure with Trichoderma and keep it in shade in a way that the moisture is maintained in the mixture. In this one month, Trichoderma multiplies itself. The pits should not be filled completely and the top 15 cm is left unfilled to allow maximum availability of water to the plant for their better survival and soil should not be compacted at this stage. However, before second irrigation, we fill the pits and again water the filled soil. Post Transplanting After ETPs have been transplanted flood irrigation of the field is done. Sugarcane sowing is done in the first week of February. Water channels along the trees are maintained to ensure timely irrigation of trees without flooding the entire field. During first two years trees are prone to wind damage especially during monsoon and, therefore, a lot of care has to be taken to maintain right balance of branches along the main trunk and has to be assured that the top of the trees are light so that the wind damage is minimized. Tree roots are susceptible to fungal attack in the first two years, hence, are regularly treated with a systemic fungicide carbendazim and an insecticide chlorpyrifos. Irrigation and Fertilizers Regular irrigation (2-3 per month) during summer months is very important for optimal growth of poplar trees. During winters, irrigation is done once a month. ENVIS Our poplar trees are regularly provided with recommended doses of nitrogen, phosphorus, potash, zinc, iron, calcium and boron along with FYM and bone-meal. From third year different doses of fertilizers are given per acre per year (Table 1). Table 1. Nutrient application to poplar plantation (kg per acre) from third year onward Fertiliser/Month Single super phosphate MOP Urea Zinc sulphate Ferrous sulphate Calcium Boron Bone-meal April 500 50 25 2 May - June - July - August - September - - 50 10 10 50 - 50 - 50 - wheat is taken as intercrop during winter months as poplar shed their leaves and sunshine reaches the ground. During summer months the leaves of trees reduce sunshine and only shade tolerant crops can be grown. Where soils are sandy to sandy loam, turmeric and ginger are very remunerative shade bearing inter-crops. But, our soil being clay loam to clay it is not possible to plant them and we have been taking only wheat as intercrop. Recently, we have also started taking fodder oats and barseem as intercrops during winter months. Economics of Poplar Based Agroforestry 100 In late April, after intercropped wheat has been harvested, full doses of phosphorous, potash, calcium and boron are added and mixed in soil by harrowing at zero cut. Field is then irrigated followed by 2-3 irrigations per month until arrival of monsoon. To maintain soil health and fertility, we add sufficient quantities of dairy manure in our soil. Bonemeal has also been found to be very beneficial for overall growth of poplars. Pruning It is very important to judiciously follow the practice of pruning of branches along the main trunk of the tree to attain maximum volume and quality wood production. It is very important that timely pruning of branches is done. In the first year of growth debudding is carried out in the lowest one third part of the stem during June-July and leader training is simultaneously done. We prune all the competing branches of the leading shoot during winter. Our period of study is seven year period from 2004 to 2011. We maintained records of year wise cost of cultivation for paddy, wheat, sugarcane and poplar separately from the farm during the given period. Year wise yields of these crops and respective sale prices for the same have been used to calculate the yearly returns. Annual net returns from PBA, paddy-wheat rotation and sugarcane crop for seven years from 2004-05 to 2010-11 are adjusted at a discount rate of 12 per cent to get the net present value for each farming option. The intercrops grown with poplar plantation under study, their yields, cost of production and returns are given in Table 2. The total returns from intercrops for the full rotation of seven years of trees have been worked out to be Rs. 118,799 with approximately Rs. 17,000 per acre per year at discounted rate of 12 per cent. The details of wood yield and return, therefrom, are given in the following pages. Trees were harvested during January 2011 through a contractor and segregated to marketable lots of oversize logs, undersize logs, roots and firewood and sold to the local contractor at negotiated prices as per details given below. Intercropping Pattern For first two years, sugarcane is grown as intercrop. After the ratoon of sugarcane is harvested at the end of second year, wheat is sown. From beginning of third year onwards Wood Sale Proceeds Out of 250 saplings planted per acre, finally survived 238 trees were harvested. The girth of these trees varied between Table 2. Discounted returns from intercrops 2004-2010 for one acre Year Intercrop 2010-11 2009-10 2008-09 2007-08 2006-07 2005-06 2004-05 Wheat Wheat Wheat Wheat Wheat Sugarcane ratoon sugarcane Yield of intercrop (q) wheat/sugarcane 14 15 15 17 18 175 350 Forestry Bulletin, 12(1), 2012 straw 10 11 11 11 14 NA NA Price of intercrop (Rs.) 1,120 1,100 1,080 1,000 750 110 110 straw 2.5 2 2 1.5 1.5 NA NA Returns from intercrop (Rs.) straw 18,180 18,700 17,200 18,950 15,600 19,250 38,500 Cost of intercrop (Rs.) Net returns (Rs.) NPV taking 12% discount rate (Rs.) 10,722 9,501 8,639 8,193 7,453 7,500 19,550 7,458 9,199 8,561 10,757 8,147 11,750 18,950 7,458 10,303 10,701 15,060 12,791 20,680 37,142 114,135 71 75-90 cm at breast height. Trees yielded 940 q of timber (3.94 q per tree), out of which, 658 q was as oversize (>60 cm mid girth) and remaining 282 q as undersize (50-60 cm girth). We also got 58.6 q roots and 62 q firewood. Price that we received for oversize logs was Rs. 813 per q, Rs. 550 per q for undersize logs, Rs. 180 per q for roots and Rs. 200 per q for firewood. Total value realized was Rs. 713,000 out of which, Rs. 534,954 was for oversize logs, Rs. 155,100 for undersize logs, Rs. 10,546 for roots, and Rs. 12,400 for firewood. Based on money realized from the sale of wood logs, roots and firewood and that from the intercrops, Table 3 was drawn for the economical analysis for the PBA system for the full tree rotation period. Overall, the PBA gave us Rs. 700,455 per acre discounted value for seven years and a net returns of over Rs. one hundred thousand per acre per year. This realization is very high in comparison with other existing land use options from the similar fields and a motivational factor to continue with poplar based agroforestry. We also tried to compare these returns from sole sugarcane production (Table 4) and wheat-paddy rotation from the adjoining fields which are the common crops grown in the locality. Detailed economical analysis for sugarcane alone is given in Table 4, and for wheatpaddy rotation in Table 5 to Table 7. There have been fluctuations in crop yields, input prices, sale prices and, therefore, in returns from sugarcane and wheat production during the study period. In general, fresh sugarcane crop gives better returns as yields are higher than the ratoon. The total returns of sugarcane cultivation have been worked out to be Rs. 188,684 for seven years with average returns of approximately 27,000 per acre per year. In order to compare the economical analysis of PBA with the traditional paddy-wheat rotation separate costs and returns for these two crops were maintained and are presented in Table 6 and Table 7. Out of these two tables, Table 7 gives returns from paddy-wheat rotation. The returns from paddy crop which is grown in summer season only is worked out to be Rs. 68,387 for the seven years of study period. To these values returns from wheat growing for the corresponding years (Table 7) was added. The discounted benefits of paddy-wheat rotation at 12 per cent over 7 year period worked out to be Rs. 359,901 against the discounted costs of Rs. 187,863. Cost-benefit ratio turned out to be 1.92. The net returns from this crop production were Rs. 172,038 for seven years and approximately Rs. 24,500 per acre per year. Table 3. Net present value (NPV) of poplar based agroforestry (in Rs.) Year t Returns from intercrop Cost of intercrop Returns from poplar 713,000 Jan-11 2010-11 0 18,180 10,722 2009-10 1 18,700 9,501 2008-09 2 17,200 8,639 2007-08 3 18,950 8,193 2006-07 4 15,600 7,453 2005-06 5 19,250 7,500 2004-05 6 38,500 19,550 Total Hence, returns per acre per year comes out 900 700 390 Cost of poplar culture 61,170 7,300 5,442 7,864 7,066 6,970 3,588 9,108 Total returns poplar and intercrop = B 7,13,000 18,180 18,700 18,100 19,650 15,990 19,250 38,500 Total cost poplar and intercrop = C 61,170 18,022 14,943 16,503 15,259 14,423 11,088 28,658 Net returns B-C (1+r)t NPV (B-C) (1+r)t 651,830 158 3,757 1,597 4,391 1,567 8,162 9,842 1 1 1.12 1.25 1.4 1.57 1.76 1.96 651,830 158 4,208 1,996 6,147 2,460 14,365 19,290 7,00,455 to Rs. 100,065. Table 4. Cost of production (per acre, r=12%) for sugarcane crop during the study period Year Crop (type) 2004 2005 2006 2007 2008 2009 2010 Fresh Ratoon Fresh Ratoon Fresh Ratoon Fresh Total 72 Yield (q) Price (Rs./q) Returns (Rs.) Cultivation cost (Rs.) Net returns (Rs.) NPV (Rs.) 350 250 302 150 330 175 325 110 110 130 130 140 230 210 38,500 27,500 39,260 19,500 46,200 40,250 68,250 19,450 13,100 22,002 11,708 26,134 13,713 24,557 18,950 14,400 17,258 7,792 20,066 26,537 43,693 37,142 25,344 27,095 10,909 25,083 29,721 43,693 188,684 ENVIS Table 5. Cost of production (per acre, r=12%) for wheat crop during the study period Net Returns (Rs.), J NPV = J(1+r)t 10,722 15,048 15,048 9,501 15,399 17,247 23,200 8,639 14,561 18,201 1,200 21,200 8,193 13,007 18,210 1.5 1,200 15,450 7,453 7,997 12,555 8 1 800 13,150 7,323 5,827 10,256 8 1 800 12,800 6,609 6,191 12,134 Total value of produce (Rs.) Cost of production (Rs.) 2,250 25,770 1,800 24,900 1,600 1.5 8 12,350 12,000 Year t Wheat yield (Rs.) Price (Rs.) Value of produce (Rs.) Yield of straw (q) Net price of straw (Rs.)/kg 2010-11 0 21 1,120 23,520 9 2.5 2009-10 1 21 1,100 23,100 9 2 2008-09 2 20 1,080 21,600 8 2 2007-08 3 20 1,000 20,000 8 2006-07 4 19 750 14,250 2005-06 5 19 650 2004-05 6 20 600 Value of straw (Rs.) ΣJ(1+r)t 103,651 Jan-11 Table 6. Cost of production (per acre, r=12%) for paddy crop during the study period Year 2010-11 2009-10 2008-09 2007-08 2006-07 2005-06 2004-05 Jan-11 t 0 1 2 3 4 5 6 Yield of paddy (q) 25 24 23 25 23 22 23 Price (Rs.) 1,100 980 880 675 610 600 600 Value of produce (Rs.) 27,500 23,520 20,240 16,875 14,030 13,200 13,800 Total cost (Rs.) 13,489 12,149 11,262 10,527 10,042 9,728 9,127 Net Returns (Rs.), G 14,011 11,371 8,978 6,348 3,988 3,472 4,673 ΣG(1+r)t NPV = G(1+r)t 14,011 12,736 11,223 8,887 6,261 6,111 9,159 68,387 Table 7. Cost of production (per acre, r=12%) for wheat-paddy rotation Year 2010-11 2009-10 2008-09 2007-08 2006-07 2005-06 2004-05 Returns from wheat 25,770 24,900 23,200 21,200 15,450 13,150 12,800 Returns from paddy 27,500 23,520 20,240 16,875 14,030 13,200 13,800 Benefits paddy+wheat 53,270 48,420 43,440 38,075 29,480 26,350 26,600 Cost of wheat 10,722 9501 8,639 8,193 7,453 7,323 6,609 Cost of paddy 13,489 12,149 11,262 10,527 10,042 9,728 9,127 Total costs wheat+paddy 24,211 21,650 19,901 18,720 17,495 17,051 15,736 Table 8. Cost benefit ratio of wheat-paddy rotation Year t (1+r)t Costs = C paddy + wheat NPV of costs = Ct(1+r)t Benefits = B paddy+wheat NPV of benefits = Bt(1+r)t 2010-11 2009-10 2008-09 2007-08 2006-07 2005-06 2004-05 0 1 2 3 4 5 6 1 1.12 1.25 1.4 1.57 1.76 1.96 24,211 21,650 19,901 18,720 17,495 17,051 15,736 24,211 24,248 24,876 26,208 27,467 30,010 30,843 187,863 53,270 48,420 43,440 38,075 29,480 26,350 26,600 53,270 54,230 54,300 53,305 46,284 46,376 52,136 359,901 Conclusion From the above data the following conclusions are drawn. NPV of PBA for the seven years period turned out to be Rs. 700,455. Hence, returns are Rs. 100,065 per acre per year. Forestry Bulletin, 12(1), 2012 Sugarcane crop gave returns of Rs. 188,684 for the corresponding period with net returns of approximately Rs. 27,000 per acre per year whereas, paddy-wheat rotation gave total returns of Rs. 172,038 for the corresponding period and Rs. 24,500 per acre per year. Net present value of returns 73 for PBA including intercrops is 4.07 times higher than the wheat paddy rotation and 3.71 times higher than the sugarcane crop farming for the corresponding period. Costbenefit ratio for wheat-paddy rotation and for sugarcane are much below 3.96 for PBA for the corresponding period. Based on more than two decades of our experience with PBA, we can very confidently say that this farming practice is not only economically very attractive but also very beneficial to the environment. The wide adoption of PBA in north-west India is a positive development. This will not only save our forests but will also bridge the increasing gap in demand and supply of the wood. 74 References Chandra, J.P. 2001.Scope of poplar cultivation. Indian Forester, 127(1): 50-60. Chandra, J.P. 2003. Role of forest based industries/plantation companies in development of agroforestry. In: Pathak, P.S. and Newaj, R. Eds. Agroforestry: Potentials and opportunities. Jodhpur, Agrobios and Indian Society of Agroforestry. Hara, S.S. 2006. Agroforestry in north-western India: A unique success. In: International Congress on Cultivated Forests, Bilbao, 3-7 October 2006. Proceedings. z ENVIS Poplar Culture for Speedy Carbon Sequestration in India: A Case Study from Terai Region of Uttarakhand Mohit Gera Indira Gandhi National Forest Academy, Dehradun – 248 006 Introduction K The countries like India that has chosen the lower limit of 15 per cent as crown cover could potentially include more agroforestry systems into the REDD-plus mechanism Forestry Bulletin, 12(1), 2012 yoto Protocol recognizes forestry as an acceptable mean of carbon sequestration, and the sector offers possibilities for significant climate change mitigation. During the Seventh Meeting of Conference of Parties (CoP 7) held at Marrakesh (Morocco) in 2001, it was decided that only afforestation and reforestation (A and R) project activities would be eligible under LULUCF sector of the clean development mechanism (CDM). The A and R project activities eligible under CDM include agroforestry, farm forestry, plantations of mixed species, and orchards. There are enough evidences to show that individuals and communities can use tree plantations sustainably to support livelihoods besides carrying out agricultural and horticultural production. However, the studies on the amount of carbon stored and trading of this carbon in international markets to provide considerable income and overall sustainable development of area are lacking. Intensive field investigations are also required to assess the suitability of different plantation models, which the individuals and communities may like to plant on different lands under CDM forestry projects. Such studies would not only provide valuable information on the scope of CDM A and R projects for sustainable livelihoods, but also encourage the marginal communities to contribute to mitigate global carbon emissions and expanding forest and tree cover (Ravindranath and Murthy, 2003). The progress on preparation of A and R CDM projects in the recent past had been much below the expected levels as the methodologies and the procedures applicable to such forestry projects are seen as complex by the project developers. Limited demand for carbon credits emanating from forestry sector has further restricted the scope of forestry CDM projects. Despite these limitations, by now, ten large-scale, two consolidated, seven small-scale methodologies and a number of tools are available for this sector to assist in project development. Besides, 40 forestry projects have already been registered by the Executive Board of CDM (UNFCCC, 2012). The Kyoto Protocol’s continuation up to 2020 is likely to further benefit the development of CDM forestry projects in future. Populus deltoides, commonly called eastern cottonwood and referred as poplar hereafter is an important agroforestry tree species, especially in the northern alluvial belt of India. It is very commonly seen along with Eucalyptus spp. on 75 agricultural fields in Punjab, Haryana, Uttar Pradesh and Tarai region of Uttarakhand and Uttar Pradesh. The species is very popular among farmers, as it offers minimum interference with the agricultural crops due to its straight bole, limited crown, and silvicultural characteristics (Gera et al., 2006). Poplar was introduced in the country about six decades back and has received wide acceptance during the last three decades because of its compatibility with agricultural crops and high productivity. Although harvested at short rotation of 6-7 yrs, poplar can attain 90 cm girth and mean annual increment of 20 m3 per ha at 8 years rotation under good care (Lal, 1991). The wood obtained from poplar is eminently suitable for manufacture of match splints, veneering products, artificial limbs, interior panelling, cheap furniture and packing cases (Singh and Negi, 2001). With this background, the present study was undertaken to estimate carbon sequestration potential, costeffectiveness and carbon benefits of different A and R options as available to individuals and communities by planting of poplar on farmlands. Other aspects such as eligibility of poplar plantations under CDM, carbon sequestration potential at national level as well as opportunities under REDD-plus are also discussed. Methodology Poplar is planted in blocks, rows and on bunds of fields and intercrops such as wheat, paddy, sugarcane, maize, mustard, pulses and others are grown along with the trees. In blocks 500 trees per ha are planted at a spacing of 5×4 m with rotation age of 6 years, whereas in rows and bund planting is carried out at a distance of 2 m. After every rotation the trees are harvested and the stumps are uprooted to prepare for fresh planting. Poplar is planted only in irrigated lands as the water requirement is high owing to its being a fast growing species. Though the farmlands vary in size, but for the purpose of calculations, all values have been recorded on per hectare basis. a. Study Site The study was carried out in Ramnagar block of Nainital District of Uttarakhand (Fig. 1) during the period of 200607. The study site consisting of three villages, viz., Kanchanpur (gram panchayat-Choi), Nandpur (gram panchayat-Khempur) and Kyaribandobasti (gram panchayat-Kyari), is located on Bail Padav-Ramnagar road in Ramnagar block of Nainital District in south of Kumaon region. The area is representative of farmlands of Uttarakhand with almost 80 per cent area dedicated to agriculture. Though, the annual rainfall in the region varies between 900-1,000 mm with uneven distribution and spread over 40-45 rainy days, there are good facilities of irrigation and land productivity is high. Geographically, the area represents Bhabar and Tarai regions with in the altitude of 1,000 m. The location of the selected villages is presented in Table 1. Fig. 1. District map of Uttarakhand (map not to scale). 76 ENVIS Table 1. Location of selected villages Name of the village Kanchanpur Choi Nandpur Kyaribandobasti Gram panchayat Choi Khempur Kyari Latitude Longitude 29°21’46’’ 29°20’13’’ 29°21’59’’ 79°08’52’’ 79°11’30’’ 79°11’30’’ Altitude (m above msl) 369 314 361 Source: GPS readings. The tree species commonly grown with agricultural crops on farmlands are poplar, eucalypts and aonla, besides horticulture crops such as litchi, mango and some citrus varieties, are also planted. The agricultural crops include wheat, paddy, maize, sugarcane, mustard and pulses. b. Proposed A and R Interventions Rapid rural appraisal and group discussions with the community and the forest department staff revealed that poplar is the most desired tree species as a plantation intervention in the event of CDM forestry project. Growers expressed willingness to plant the species as a block, rows and on farm periphery as bund plantation. The silvicultural details of selected plantation interventions of poplar and the planting stock available are presented in Table. 2. c. Recording of Field Observations The field observations on growth of selected plantation interventions was taken as per the structured data sheets prepared for recording of data to estimate the eligible carbon pools under CDM, viz., above ground biomass (AGB), below ground biomass (BGB), woody litter and the soil carbon. Similar observations were also recorded for the selected areas where there would be no plantation, to act as a baseline data. In order to estimate the above ground biomass for the selected plantation interventions, the existing stands of three different ages of poplar blocks were selected from within the available plantations on farmlands, and data on girth and height was recorded for all the trees in randomly selected quadrates of 25 x 20 m size. For bund plantations, the data was recorded from boundary plantations as existing on the farmlands by laying out linear strips of 10 x 125 m. A minimum of 3 quadrates/strips for three different ages representing tree growth were taken for recording field observations for both the plantation interventions. For calculating the mean annual increment (MAI) on the farmlands under bund plantations, it was assumed that the farm size is 0.25 ha (50 x 50 m) and 96 trees are planted at a spacing of 2 m as commonly practiced in the selected villages. The data was used to estimate the MAI for both the plantation interventions, which was calculated through the already published volume equation by Dhanda and Verma (2001). Calculated stem volume was converted to biomass by multiplying it with biomass expansion factor and wood density as per good practices guidelines provided by Intergovernmental Panel on Climate Change (IPCC, 2003) to obtain above ground biomass (AGB). The below ground biomass (BGB) was calculated by multiplying the AGB with IPCC default value of 0.27 (IPCC, 2003). The carbon sequestered was calculated by multiplying the biomass by 0.45, which is again an IPCC default value. d. Estimation of Soil Organic Carbon Three soil samples were collected from each plantation site selected for estimation of above ground biomass at three different depths; i.e., 15, 30 and 45 cm for analysing the soil organic carbon (SOC), which was estimated as per Walkley and Black (1934) and Walkley (1947). e. Observations on Costs and Benefits Data on planting and silvicultural management costs involved in raising and maintenance, of the selected poplar plantation interventions, and on all costs related to harvest and marketing along with the benefits likely to be received at the end of the rotation period were also recorded so as to assess the cost effectiveness of these plantations, exclusive and inclusive of carbon benefits. f. Model approach The spreadsheet model PRO-COMAP, acronym ‘project based comprehensive mitigation assessment process’ was employed for analysis of data. The model is based on the description, instruction and explanations as given by Sathaye et al. (1995) and Makundi and Sathaye (1999). The excel spread sheet model has been designed specifically to undertake a Table 2. Brief silvicultural details of selected plantation interventions Plantation intervention Poplar block Spacing (m) 5×4 Trees/ha 500 Survival (%) 100* Rotation (yrs) 6 Poplar bund 2 384** 100* 6 Planting material Harvest and planting ETP of and other ETP of and other Uprooted and planted fresh on completion of every rotation during the CDM project period. Uprooted and planted fresh on completion of every rotation during the CDM project period. G3, G48 clones G3, G48 clones * Failed plants assumed to be fully replaced ** For bund plantation, a farm size of 0.25 ha was assumed Forestry Bulletin, 12(1), 2012 77 comprehensive assessment of the role of tree plantations in climate change mitigation. The model uses data on selected carbon pools as collected from the field, viz., above ground biomass, below ground biomass, soil carbon and woody litter along with data on costs and benefits throughout the life of the selected plantation interventions, as input. The costs include those incurred on initial planting, silvicultural operations, harvesting, marketing and other recurring costs on maintenance and protection, monitoring of biomass, soil carbon and the opportunity cost of the land. The benefits were calculated on the basis of prevailing market rates of wood products, viz., veneer log, chip log and the fuel wood, besides carbon benefits, which were estimated separately. The relevant data, provided as key input to the model is presented in Tables 3 and 4. The model estimates the carbon stock changes based on the rotation age and mean annual increment in biomass growth of species planted and decomposition rate of litter and accumulation time of carbon in soils. Since the study involved plantation intervention on farmlands, it was assumed that the baseline carbon stock would only be the soil carbon, and would remain static during the period of assessment. The static baselines are valid under CDM for projects where no changes in anthropogenic or natural activity are expected over the project period (Richards and Anderson, 2001) as is the case for plantation on farmlands. During the plantation period, the major changes in carbon stock accrue due to the changes in above ground and below ground biomass. The falling woody litter from time to time also contributes to the carbon pool, which though minimal, has been accounted for on annual basis, along with soil uptake, during accumulation period of 6 years. The analysis period selected for the study was 30 years (2008-2038) and the model was run for the selected period. The model carry out the analysis under two scenarios, viz., Baseline scenario, which is the carbon mitigation under the ‘business as usual’ scenario, where no deliberate effort is made to increase carbon sequestration, and the ‘Mitigation scenario’, where mitigation options, viz., tree plantation activities are undertaken for carbon mitigation over a defined period of time. Although carbon sequestration due to harvested wood products is not eligible for first commitment period; i.e., 2008-2012, the model was run to calculate output for both the cases; i.e., ‘with’ and ‘without wood products’. The output of the model consists of values with respect to annual incremental carbon sequestration, cost effectiveness indicator, viz., Internal rate of return (IRR) ‘with’ and ‘without carbon benefits’, and the likely carbon benefits under the selected carbon price scenarios for both the plantation interventions. Three different carbon price scenarios were assumed to assess whether the carbon benefits as estimated under these scenarios can provide significant incentives to the growers so that they get motivated to go for the selected plantation interventions. The three carbon price scenarios are Scenario I, where the carbon price remains fixed at $5 per t CO2, Scenario II, where the price begins at $5 per t CO2 and increases every year at the rate of 2 per cent and Scenario III, where the carbon price begins at $5 per t CO2 and increases at the rate of 5 per cent every year. A back stop price of $50 per t CO2 was assumed for Scenarios II and III. The cost effectiveness indicator, viz., IRRs were also calculated for the plantation interventions with carbon benefits under these three carbon price scenarios. Results The carbon sequestration potential and average annual incremental carbon stock along with estimated carbon benefits for the two plantation interventions is given in Table 5. A sequestration potential ‘without wood products’ for the analysis period of 30 years is observed to be 39.76t C per ha for block plantation which was substantially lower when compared with ‘with wood product’ case; i.e., 72.17t C per ha, whereas sequestration potential of 31.48t C per ha has been observed for bund plantation under ‘without wood products’ and 58.86t C per ha ‘with wood products’, respectively. The carbon benefits calculated on the basis of carbon price of $5 per tCO2 and at dollar rate of Rs. 55/- Table 3. Key input data on carbon pools to PRO-COMAP Plantation intervention Mean annual increment (t/ha/yr) Baseline AGB (t/ha) Baseline soil carbon (t/ha) Soil carbon uptake (t/ha/yr) Woody litter (t/ha) Poplar block 19.35 0 29.60 0.93 (6)* 0.26 (2.94)** Poplar bund 14.86 0 33.75 0.56 (6)* 0.21 (2.94)** * Accumulation period in years ** Decomposition period in years 78 ENVIS Discussion Table 4. Key input data on wood products to PRO-COMAP W ood product as per cent of M AI Plantation intervention Poplar block Poplar bund Chip logs 20 (30)* 20 (30)* Veneer logs 60 (30)* 60 (30)* F uel wood 18 (0)* 18 (0)* * Product life in years are Rs. 1,337 per ha per yr and Rs. 1,060 per ha per yr for poplar block and bund plantations respectively, in the absence of wood products. Higher benefits of Rs. 2,428 per ha per yr and Rs. 1,817 per ha per yr have been estimated with the inclusion of wood products under the poplar block and bund plantations, respectively. The data in Table 6 shows the IRRs ‘with’ and ‘without carbon benefits’ under the three carbon price scenarios. The poplar block plantation showed an increase in IRR from 61.20 per cent to 69.5 per cent, 70.9 per cent and 74.3 per cent for the three price scenarios respectively, ‘without wood products’ while, for the ‘with wood products’ case the increase recorded is to 69.8 per cent, 71.5 per cent and 75.4 per cent, respectively. The poplar bund plantation showed an IRR of 52.2 per cent ‘without carbon benefits’ which increases to 58.3 per cent, 59.6 per cent, and 62.7 per cent respectively, for the three price scenarios when wood products are not included. Under the ‘with wood products’, a similar trend was seen for this intervention, which showed an IRR increases to 58.6 per cent, 60.2 per cent and 63.9 per cent, respectively. a. Carbon Sequestration Potential The interventions on poplar block and bund plantations showed a sequestration potential of 1.33t C per ha per yr and 1.05t C per ha per yr respectively, when wood products are not included and 2.41t C per ha per yr and 1.80t C per ha per yr respectively, along ‘with wood products’. The sequestration potential depends on the MAI of tree growth; i.e., above and below ground biomass growth in terms of t/ ha/yr. Though, woody litter and soil carbon also have been taken into account for calculations, their contribution has been observed to be small and rather negligible as compared to wood growth. Higher the MAI, higher will be the sequestration potential, provided there is no harvest during the analysis period. In case of harvest during the analysis period, the carbon pools get adversely impacted due to IPCC default approach which says that, the moment trees are harvested, the equivalent CO2 is deemed to have been emitted in to the atmosphere (IPCC, 2003). The present model used for calculation of sequestration potential is programmed for IPCC default approach. Therefore, the plantation interventions on poplar, which is short rotation fast growing species, have given a low sequestration potential. The MAI, which is estimated in terms of t per ha per yr is also influenced by density of plantations, and for this reason, bund plantation are expected to show lesser sequestration potential as compared to block plantations of the same species. Table 5. Annual incremental carbon, total carbon sequestered, and likely annual carbon benefits Plantation intervention Initial cost^ (Rs/ha) Poplar block 13,700 Poplar bund 7,450 Incremental carbon Per unit-area Annual (tC/ha) (tC/ha/yr) 39.76 1.33 (72.17) (2.41) 31.48 1.05 (53.86) (1.80) Annual sequestration (tCO2/ha/yr)* Benefit @$5/t CO2 (Rs/ha/yr)** 4.86 (8.83) 3.85 (6.61) 1,337/(2,428/-) 1,060/(1,817/-) ^ Includes all costs incurred for establishment of plantations. * 1tC = 3.67tCO2 ** 1$ = Rs. 55/Figures in parenthesis refer to values for ‘with wood products’ case Table 6. Internal rates of returns under different carbon price scenarios Internal Rate of Return (IRR %) Plantation intervention Without carbon benefits Poplar block Poplar bund 61.20 52.20 Scenario I 69.5(69.8) 58.3 (58.6) With carbon benefits Scenario II Scenario III 70.9(71.5) 74.3(75.4) 59.6 (60.2) 62.7 (63.9) Scenario I - Carbon price $5, 1US $ = Rs. 55/Scenario II - Carbon price $5 + 2% annual increase (backstop price $50/tCO2) Scenario III - Carbon price $5 + 5% annual increase (backstop price $50/tCO2) Figures in parentheses show values for the ‘with wood products’ case. Forestry Bulletin, 12(1), 2012 79 These findings are supported by Hooda et al. (2007), who reported a sequestration potential of 1.98t C per ha per yr for poplar block plantations for similar area of Uttarakhand. A few other studies, viz. Gera et al. (2006) have reported a sequestration potential of 2.54 and 1.42t C per ha per yr for poplar block, and bund plantations, respectively for farmlands of Rupnagar, Punjab. Ravindranath et al. (2007) reported an average sequestration potential of 2.23t C per ha per yr for short rotation interventions involving fast growing species, such as Eucalyptus, Casuarina, Acacia and Gmelina arborea, planted for the purpose of fuel wood, industrial wood and poles. The sequestration potential in the same range with an average of 1.55t C per ha per yr has also been reported by Makundi and Sathaye (2004) for agroforestry species. Another study by Updegraff et al. (2004), from Minnesota, USA, reported that a short rotation plantation of hybrid poplar was estimated to yield sequestration levels of 1.8 to 3.1t C per ha per yr. It is observed in the present study that the selected plantation interventions have recorded substantially higher sequestration potential when the harvested wood products are included in the sequestered carbon pools. Poplar, which is harvested in six years, start giving wood products immediately after harvest and the harvested wood product carbon pool starts growing with every harvest, and adds to the total carbon sequestered pool. Therefore, a substantial increase in sequestration levels ‘with wood products’ as compared to the sequestration levels ‘without wood products’ is observed in the study. Several research findings support the increased sequestration levels when wood products are also accounted towards calculation of sequestration potential for a given analysis period. Hooda et al. (2007) reported a sequestration potential of 3.33t C per ha per yr for poplar block plantation ‘with wood products’, which was much higher as compared to 1.98t C per ha per yr reported ‘without wood products’. b. Carbon Benefits The carbon benefits on account of carbon sequestration directly depend on the sequestration rate per unit area per unit time. Though, farmers may not plant a particular intervention squarely for carbon benefits, significant economic returns on account of carbon benefits can be a motivating factor in these plantation interventions. It would be important to note here that unless the individual farmers and communities get sufficient monetary returns, besides being convinced of the carbon benefits, they would be unlikely to participate in the CDM like projects. Makundi and Sathaye (2004) have also highlighted the importance of agroforestry as a mitigation option and observed them to be more cost effective than afforestation and reforestation of degraded or wastelands. 80 Due to very high price of poplar wood in Indian timber markets presently, the economic returns from agroforestry and farm forestry poplar plantations are very high and are in the range of around Rs. 150,000 per ha per yr (ICFRE, 2012). These returns are huge compared to likely carbon benefits of around Rs.1,000-2,500 per ha annually, as estimated in the present study. This huge difference of comparative benefits may not motivate farmers to opt for forestry CDM projects involving fast growing species like poplar. These interventions could face another problem of addressing ‘additionality’, which is a must for CDM projects. The conditions of ‘additionality’ disallow financially most attractive plantation interventions on the basis that they would form a ‘business as usual’ scenario and hence not eligible to be considered under CDM. However, there are ways to address ‘additionality’ when small and marginal farmers are involved. A case of CDM forestry project namely ‘Reforestation of Severely Degraded Landmass in Khamman District of Andhra Pradesh under ITC Social Forestry Project’ will be appropriate to site here. The project deals with planting of eucalypts on four years rotation, which is also a fast growing tree species with handsome economic returns. The project proponents have addressed the requirement of ‘additionality’ by following ‘barrier analysis’ and have demonstrated that lack of investment, technological knowhow, institutional framework and prevailing market risks are the key barriers, which would be dealt with only, if there is a CDM forestry project involving eucalypts plantations. Therefore, CDM like forestry projects can be developed for the poplar based agroforestry systems also. c. Eligibility of Studied Plantation Interventions under CDM The eligibility of the plantations depends on the definition of ‘forest’ as accepted by the host country for forestry CDM projects. India’s definition of ‘forest’ is: A forest is a minimum area of land of 0.05 ha with tree crown cover (or equivalent stocking level) of more than 15 per cent having trees with the potential to reach a minimum height of 2 m at maturity in-situ (UNFCCC, 2008). This definition requires that any land devoid of adequate tree cover, say agriculture, wasteland or forest will have to be either afforested or reforested on a minimum area of 500 sq. m with such trees with a potential to reach a minimum height of 2 m at maturity and so densely planted that the crown cover reaches from less than 15 per cent before planting to more than 15 per cent during the maturity of the tree crop. Out of the three parameters of minimum area, crown cover and tree height on maturity, the requirement of tree ENVIS crown cover is crucial. Since, a lot of poplar plantations are preferred on bunds, it is necessary to ensure that such plantations qualify under CDM. A poplar tree achieves a crown diameter of 5.8 m on maturity (Dhiman, 2006). When the trees are planted on bunds the effective value of crown cover will gradually decrease as the farm size increases. Accordingly, it has been calculated that if poplar trees are planted on bund at a spacing of 2 m the crown cover achieved by the plantation on 0.5 ha of farmland would be 15.77 per cent which qualifies the requirement of CDM. As observed in the field, the farm sizes are seldom bigger than 0.5 ha in case of small or marginal farmers and we can easily say that most of these plantations are likely to be eligible under CDM. d. C-Sequestration Potential of Poplar Plantations at National Level Available literature on carbon sequestration potential of different poplar plantation models is limited. The carbonsequestration potential of the species as estimated by the recent studies is presented in Table 7. The variation in the sequestration potential as reported by the different studies may be attributed mainly to the mean annual increment which varies with site, density of plantation as well as quality of planting stock utilized for raising the plantations. Table 7. Carbon-sequestration potential as reported by different researchers S. no. Species Nature of plantation 1. Poplar 2. Poplar Block Bund Block C-sequestration potential tC/ha/yr 2.54 (4.42)* 1.42 (2.46) 1.98 (3.33) 3. Poplar Block 1.33 (2.41) Gera et al., 2011a 4. Poplar Block Bund Block Bund 2.20 (3.83) 1.23 (2.13) 2.01 (3.50) 1.33 (2.30) Gera et al., 2011b Average sequestration potential Reference Gera et al., 2006 Hooda et al., 2007 * Figures in parenthesis are for ‘with wood products’ case. Out of an area of 362,700 ha estimated to be under poplar plantations in India, an area under commonly planted with P. deltoides is 312,000 ha (ICFRE, 2012), which is mainly planted on farmlands as a cash crop in various combinations along with agricultural crops. It is further estimated that 60 per cent of this area is planted as block plantations and 40 per cent as bund plantations (ICFRE, 2012). Utilizing the above data on extent of plantation and average values of carbon-sequestration potential, it is estimated that at national level, planting of poplar as a block may lead to a sequestration of 376,272t C per yr ‘without wood products’ Forestry Bulletin, 12(1), 2012 and 655,200t C per yr ‘with wood products’. The sequestration potential in case of poplar bund plantation could be 165,984 tC per yr ‘without wood products’ and 287,040 tC per yr ‘with wood products’. Overall the existing carbon sequestration levels due to poplar plantations under agroforestry is 542,240t C per yr when wood products are not accounted for and 942,240t C per yr inclusive of wood products. These levels can however be raised multifold by bringing in more and more agricultural lands under agroforestry and farm forestry. e . Agroforestry in REDD-Plus: Opportunities and Challenges Reduced emissions from deforestation and degradation (REDD-plus) envisages a mechanism in which countries chose to reduce national level deforestation to below an agreed baseline or increase removals by conservation of forest carbon stocks, sustainable management of forests and enhancement of carbon stocks; and receive compensation or rewards. Agroforestry can be a part of REDD-plus depending on the definition of forest chosen by a given country. Agroforestry has not explicitly been mentioned as part of R EDD -plus or any current United Nations Framework Convention for Climate Change (UNFCCC) mechanism. However, considering the UNFCCC definition of forest, a great deal of existing agroforestry systems worldwide could qualify to be an integral part of a REDD-plus. Though the term ‘forest’ under REDD-plus is yet to be defined, the forest definition agreed to by UNFCCC in the context of the Kyoto Protocol define forest in terms of minimum area, crown cover and tree height on maturity. Taking India’s definition of forest into consideration, many agroforestry systems would automatically qualify for REDD-plus. Zomer et al. (2009) found that about 46 per cent of agricultural land globally has at least 10 per cent tree cover. The tree cover on 50 per cent of agricultural land in Southeast Asia and Central America is at least 30 per cent, while in SubSaharan Africa, it is about 30 per cent on 15 per cent of agricultural lands. This implies that most tree crop production and agroforestry systems meet the minimum requirements of forest. The countries like India that has chosen the lower limit of 15 per cent as crown cover could potentially include more agroforestry systems into the REDD-plus mechanism. Agroforestry can reduce emissions from forest degradation through increased production of on-farm timber and fuel wood especially in instances of restricted access to forests or limited supply in ‘open access’ forests (Minang et al., 2011). Fuel wood, charcoal and small timber have been documented as frontline drivers of forest degradation in several countries including India and to some extent a driver of deforestation 81 (Minang et al., 2011). Therefore, increasing on-farm timber and fuel wood production is likely to relieve forests of pressures from an increasing demand for timber and fuel wood. Agroforestry has strong implications for sustainable development because of the interconnection with food production, rural poverty, and environmental degradation. It may provide a viable combination of carbon storage with minimal impact on the food production. Policies that promote agroforestry will help to increase carbon sequestration in agro-ecosystems, thereby providing climate change mitigation benefits (Watson et al., 2000). Sudha et al. (2006) also reported that agroforestry systems provide significant sustainable development benefits such as food security and secure land tenure in developing countries, increasing farm income, restoring and maintaining aboveground and below ground biodiversity, maintaining of watershed hydrology, and social conservation. Agroforestry also mitigates the demand for wood and reduces pressure on natural forests (Pandey, 2002). Success of agroforestry, however, is based on an enabling legal and policy environment that guarantees tree rights and ownership, investments and a market infrastructure suited to agroforestry and tree-based systems. The focus on agroforestry must filter down to block and village level and forest department must cooperate and support by providing quality planting stock, technical guidance and enabling farmers to freely harvest, transport and sell their produce. The role of wide and effective network of extension services, availability of certified planting stock and buy back arrangements with wood based industries will also be crucial in success of agroforestry in the country. References Dhanda, R.S. and Verma, R.K. 2001. Timber volumes and weight tables of farm grown poplar (P. deltoides Bartr. ex Marsh) in Punjab. Indian Forester, 127(1): 115-125. Dhiman, R.C. 2006. Breaking barriers for A and R projects in agroforestry. In: Meeting of Stakeholders on Proposed Policy Reforms to Remove the Barriers to CD A&R Projects, Dehradun, 14-15 September 2006. Proceedings. Dehradun, ICFRE. Gera, M.; Mohan, G.; Bisht, N.S. and Gera, N. 2006. Carbon sequestration potential under agroforestry in Rupnagar district of Punjab. Indian Forester, 132(5): 543-555. Gera, M.; Gera, Mohit and Bisht, N.S. 2011a. Carbon sequestration potential of selected plantation interventions in terai region of Uttarakhand. Indian Forester, 137(3): 273-289. 82 Gera, M.; Mohan, G.; Bisht, N.S. and Gera, Neelu. 2011b. Carbon sequestration potential of agroforestry under CDM in Punjab state of India. Indian Journal of Forestry, 34(1): 1-10. Hooda, N.; Gera, M.; Andrasko, K.; Sathaye, J.; Gupta, M.K.; Vasistha, H.B.; Chandran, M.; and Rassaily, S.S. 2007. Community and farm forestry climate mitigation projects: Case studies from Uttaranchal, India. Mitigation and Adaptation Strategies for Global Change, 12(6): 1099-1130. ICFRE (Indian Council of Forestry Research and Education). 2012. Country report on poplars and willows. Dehradun, ICFRE. IPCC (Intergovernmental Panel on Climate Change). 2003. Good practice guidance for land use, land-use change and forestry. Japan, Institute for Global Environment Strategies. Lal, P. 1991. Improved package of practices for poplars under agroforestry. Indian Forester, 117(3): 168-76. Makundi, W.R. and Sathaye, J.A. 1999. COMAP: Description and instructions manual. Berkeley, Lawrence-Berkeley Laboratory, Environmental Energy Technologies Division. Makundi, W.R. and Sathaye, J.A. 2004. GHG mitigation potential and cost in tropical forestry – relative role for agroforestry. Environment, Development and Sustainability, 6(1-2): 235-260. Minang, P.A.; Bernard, F.; van Noordwijk, M. and Kahurani, E. 2011. Agroforestry in REDD +: Opportunities and challenges. ASB Policybriefs No. 26. Nairobi, ASB. Pandey, D.N. 2002. Carbon sequestration in agroforestry systems: A viewpoint. Climate Policy, 2(4): 367-377. Ravindranath, N.H. and Murthy, Indu K. 2003. Clean development mechanism and forestry projects: Strategy for operationalization in India. Indian Forester, 129(6): 691- 706. Ravindranath, N.H.; Murthy, Indu K.; Chaturvedi, R.K.; Andrasko, K. and Sathaye, J.A. 2007. Carbon forestry economic mitigation potential in India, by land classification. Mitigation and Adaptation Strategies for Global Change, 12(6): 1027-1050. Richards, K. and Anderson, K. 2001. The leaky sink: Persistent obstacles to a forest carbon sequestration program based on individual projects. Climate Policy, 1(1): 41-54. Sathaye, J.A.; Makundi, W. and Andrasko, K. 1995. A comprehensive mitigation assessment process (COMAP) for the evaluation of forestry mitigation options. Biomass and Bioenergy, 8(5): 345-356. ENVIS Singh, S.P and Negi, A. 2001. Utilisation of poplar for wood composites. Indian Forester, 127(2): 154-59 Sudha, P.; Ramprasad, V.; Nagendra, M.D.V.; Kulkarni, H.D. and Ravindranath, N.H. 2006. Development of an agroforestry sequestration project in Khammam district of India. Berkeley, Lawrwnce Berkeley National Laboratory. UNFCCC (United Nations Convention on Climate Change). 2008. Country’s submission of ‘forest’ definition. [Available at: www.http://search.unfccc.int/cdm/ query.html] UNFCCC (United Nations Convention on Climate Change). 2012. [Available at: www.http://search.unfccc.int/cdm] Updegraff, K.; Baughman, M.J. and Taff, S.J. 2004. Environmental benefits of cropland conversion to hybrid poplar: Economic and policy considerations. Biomass and Bioenergy, 27(5): 411-428. Forestry Bulletin, 12(1), 2012 Walkley, A. 1947. An examination of methods for determining organic carbon and nitrogen in soils. Journal of Agricultural Science, 25(4): 598-609. Walkley, A. and Black, I. A. 1934. An examination of degtjareff method for determining soil organic matter and a proposed modification of the chromic acid titration method. Soil Science, 37(1): 29-38. Watson, R.T.; Noble, I.R.; Bolin, B.; Ravindranath, N.H.; Verardo, D.J. and Dokken, D.J. 2000. Land use, land-use change, and forestry: A special report of the IPCC. Cambridge, Cambridge University Press. Zomer, R.J.; Trabucco, A; Coe, R. and Place, F. 2009. Trees on farm: Analysis of global extent and geographical patterns of agroforestry. Working Paper No. 89. Nairobi, World Agroforestry Centre. z 83 Status of Poplar Diseases in India Y.P. Singh, Kartik Uniyal, Archana Bagwari, Kavita, Santan Barthwal1, R.C. Dhiman2 and J.N. Gandhi2 Forest Pathology Division, Forest Research Institute, Dehradun - 248 006 1 Genetics and Tree Propagation Division, FRI, Dehradun - 248 006 2 WIMCO Seedlings Ltd., Kashipur Road, Rudrapur - 263 153 Introduction P regarding the overuse of oplars and willows are very important tree species for the ecology and economy of countries in temperate and subtropical zones of the world. Poplar species in their natural range occur interspersed throughout the forests of temperate regions of northern hemisphere between the southern limit of around latitude 300 N and northern limit of latitude 450 N (Tewari, 1993). They are easy to cultivate and form an important component of forestry and agroforestry systems, often for the livelihood of small-scale farmers and native communities (NPC, 2012). Six indigenous and three exotic species of poplars and 32 species of willows are reported in India. Populus deltoides has gained considerable importance in agroforestry plantations of Jammu and Kashmir (J. and K.), Punjab, Haryana, Uttarakhand (U.K.) and Uttar Pradesh (western part of U.P.) states of India, mainly due to its deciduous nature, fast growing habit and high industrial demand (Chandra et al., 2001). They are also known for their fast growth, easy vegetative propagation, enrichment of the soil with litter and high production (10 to 30m3ha-1yr-1) on a short rotation of eight to 12 years (Kishwan and Kumar, 2003). So, they occupy a unique and important position in rural economy of India. In natural forests, a biological balance is normally maintained between the vegetation and its diseases and insects which, generally, remain at an endemic level. Therefore, wherever feasible, natural forests should be maintained within the limits of economics and utility of the crop. The natural stocking may, however, be too slow growing to meet the requirements of intensive management seeking maximum financial gain. Since the latter half of 20th century, there has been a rapid expansion of forest based industries, which is particularly high for pulp and paper. To meet this changing pattern of demand and also to meet the deficit of wood throughout the world, plantations of quick growing species are being raised, particularly in developing countries. Diseases and insects assume considerable significance in plantations (Bakshi, 1976). single clones and use of Clonal Forestry and Forest Diseases Monocultures are widely believed to attract diseases and pests and to be more vulnerable than mixed stands, especially in the long term. Disease problems have, therefore, posed the question large monoclonal plantations 84 The importance of vegetative propagation in forestry is well understood, but not so well established particularly in India. The transfer of non-additive characteristic ENVIS is difficult through seed production approaches but is routinely possible through vegetative propagation (Zobel and Ikemori, 1983). Therefore, it is attractive for achieving gains which have low heritabilities such as growth and cellulose yields. It is especially useful for utilizing hybrids when mass production of hybrids is difficult. Vegetative propagation is an excellent approach for developing clonal forestry programmes. It can eliminate inbreds, provide adapted clones, mass produce valuable genotypes, control genetic diversity and, more importantly, helps in predicting yield in plantation programmes. Clonal forestry refers to the large scale deployment of relatively few (typically 10-50) known superior clones that have proven their superiority in their clonal test (Bjurden, 1989; Libby and Ahuja, 1993; Talbert et al., 1993). Three main purposes may be mentioned for the use of clones in forestry: to produce a more uniform product, to improve the forest by using a genetically superior planting stock and to offer customer-tailored improved material. Clonal forestry with poplars is common in countries with subtropical and temperate climates like Belgium, France, Italy, Spain, USA and Canada. Poplars are propagated vegetatively through cuttings in order to maintain their genetic purity. Many a times, single clone of poplars have been propagated extensively. Clones of P. deltoides have shown a great promise in U.K., U.P., Haryana and Punjab (Sharma, 2009). Several promising clones of G series, D, Sc and St series, L and WSL series have been identified and, subsequently, planted in farm/agroforestry systems throughout Punjab, Haryana, Tarai region of U.K., western part of U.P., some parts of Bihar, West Bengal (W.B.) and Assam (Mishra et al., 2010). A major concern with respect to clonal plantation forestry is the safeguarding of stand adaptability; i.e., the ability to face a catastrophic biotic or abiotic perturbation. The most widespread use of clonal plantings has been with the willow family (Salicaceae), involving willow (Salix) and poplar (Populus) species and hybrids (Hall, 2000). Does increased use of clonal planting stock contribute to a decrease in stand viability? Such questions were theoretically explored by considering simplified situations in which susceptibility to the unknown hazard is controlled by one single diallelic locus. Results varied according to: (i) the frequency of susceptible genotypes, and (ii) the level of acceptable stand mortality. If the former is higher than the latter, increasing the number of clones will result in greater susceptibility in the multiclonal variety. If the former is low, increasing clone numbers boosts the probability of success, usually up to 10 genotypes. To cover a wide range of situations, Bishir and Roberds (1999) recommend clonal mixtures of 30 to 40 genotypes. Forestry Bulletin, 12(1), 2012 Presently, around two dozen clones are commercially grown in the country. However, Clone G48 (36.2), WSL22 (18.8 per cent), Udai (11.9 per cent), WSL39 (9.1 per cent), WSL32 (2.9 per cent), Wimco81 (5.3 per cent) and S7C15 (5.8 per cent) together constitute over 90 percent of the total planted poplar in the Punjab, Haryana, U.K. and U.P. states of the country. Whereas, G48, WSL22, WSL39 have widespread acceptability, many others are restricted to a few locations. Similarly, S7C8, WSL A/49 and Bahar are mainly grown in the states of U.P. and U.K. and they are almost non-existent in the states of Punjab and Haryana. G3, once a dominate clone over the greater part of the poplar growing region, is now restricted to only Aligarh and Bulandshahar districts of U.P. and in semi- arid part of Haryana where it does not attract infection of Bipolaris sp., may be due to drier weather. Similarly, clone G48, the most preferred clone among the growers over the great part of region of intensive poplar culture (RIPC) (Dhiman, 2012), is not grown towards eastern limits especially eastward Bareilly (U.P.) because of its high susceptibility to sap sucking insects including red mite (Dhiman, 2007). Clone WSL22 is now becoming more acceptable in its place in many locations. The notion is widely accepted that the exclusive use of a single genotype (clone) over a large area entails an enormous risk: if the clone fails for any reasons, the failure could be total over the entire area, thus, causing almost insurmountable problems for the managemement of the forest and for the industries depending on it. Monocultures are widely believed to attract diseases and pests and to be more vulnerable than mixed stands, especially in the long term. Disease problems have, therefore, posed the question regarding the overuse of single clones and use of large monoclonal plantations (Stelzer and Goldfarb, 1997). It is unlikely that monoclonal cultures and the wide use of some clones are the only explanation to increased disease, but they act as contributing factors. The health hazards come in three forms: first they may constitute a large, undivided risk, and it may be better to spread risks; second, the concentration of a susceptible plants per se might increase the disease rate of the individual, while the interaction between neighbours of different susceptibility might reduce those rates; third, monoculture might stimulate the evolution of new, more virulent or aggressive form of the parasite. Because yields typically decline, crop monoculture is commonly considered as not sustainable. The focus has been to develop disease resistance within individual clones, but these clones have proved to be highly susceptible to new varieties of diseases. The diseases keep growing and have caused Germany to more or less abandon poplars. Nevertheless, these incidents have not provided poplar growers with sufficient incitement to focus on more diverse alternatives. 85 All programmes employing clonal forestry should have an underlying breeding programme of selection, breeding and testing to identify clones of ever-increasing genetic merits. However, when clonal forestry is the deployment option, at least some of the genetic tests must be established identified clones for the purpose of ranking clones and selecting which ones to propagate operationally. Growers that practice crop monoculture generally do so for economic reasons. The selected crop is the most profitable and any profitability loss from yield declines are less than that which occurs from any rotational options available. In these situations, the ability to minimize the losses associated with monoculture can provide the best option to increase productivity and profitability. Multiclonal varieties have been regarded as a means of deploying not-to-resistant clones (Schriner, 1965). Further, mixed stands may have the advantage of offering a more varied scenery and, under certain conditions, of giving a higher production (Heybroke, 1978). The various annual reports of WIMCO (from mid 80s to early 90s) refer to leaf blight and its presence in few clones, including G3. However, neither quantification of the disease in terms of prevalence/incidence nor its geographical distribution has been specified making the reporting empirical. Though, the repeated references of the blight in the annual reports underlined its seriousness and impact - as a highly productive and popular clone (G3) was withdrawn by the company in due course. For example, in Yamunanagar District of Haryana, G3 was raised as high as 90 per cent of the total poplar plantations during 1985 -1995. After that, G3 clone was completely withdrawn due to its high blight susceptibility. On the other hand, same clone is still grown in Aligarh district of U.P. as blight is absent owing to environmental conditions (moderate rainfall). The specificity of the pathogen (to G3 clone) at one hand and its wider presence on the other hand support the contention of Bishir and Roberds (1999) who recommended clonal mixtures of 30 to 40 genotypes to cover a wide range of situations. In spite of this fungal catastrophy in the recent past, the existing poplar plantations are still heavily dependent on limited number of clones, probably not more than half a dozen in a state (for example, G48, Udai, WSL22, WSL39, S7C8, etc. for Uttarakhand), if political demarcation defies the ecological one (Mishra, 2011). Poplar Diseases Distribution and Status Poplar suffers from a number of diseases as they are being raised as single clone monocultures and are, thus, prone to disease outbreaks. In agroforestry, the situation may further 86 aggravates, where pathogens often diverse their activity from the common host range and cause extensive damage to either of the intercrop species. An account of principal diseases of poplars occurring on indigenous and exotic poplars in India is presented in Table1 to 3. Work on poplar diseases started almost at the same time when exotic poplars were introduced in India; i.e., late 50s. It was pioneered by Dr. K.D. Bagchee who is also known as Father of Forest Pathology in India (Table 2). The surveys on indigenous poplars were confined to two northern states namely, J. and K. and H.P. Other Himalayan states, especially north-eastern ones, where the indigenous poplars have substantial presence were not covered. P. ciliata seems to be most susceptible among indigenous poplars as it is affected by maximum numbers of pathogens (11). No disease has been reported on P. glauca and P. rotundifolia. M. ciliate was the only disease that affected all the species of indigenous poplars showing its wide host range. Among exotic poplars, the surveys were predominantly taken up in nurseries of U.P. especially the western part followed by H.P. Besides, Haryana, Punjab and J. and K. were also surveyed. Further, maximum number of fungal pathogens were recorded on P. deltoides (32) followed by P. x euramicana (18) and P. nigra (10). Whereas, in plantations, highest number of surveys were conducted in U.P. followed by J. and K. and diseases were recorded on three exotics, P. deltoides, P. x euamericana and P. nigra. Out of these hosts, P. x euramicana had maximum fungal infections (8) followed by P. deltoides (7). One of the defining facets of the disease is its economic value (Agrios, 1978). However, the assessment of losses in term of economic values is singularly missing in all the studies on poplar diseases, though, it is critical in terms of cost benefit assessment of the poplar culture. Percent mortality of seedlings due to incidence of different diseases in the nursery of WIMCO Research and Development Centre, Rudrapur is shown in Table 4 that ranged from 0.14 to 29.25 per cent. The large scale mortality due to Alternaria species was observed in Bazpur nursery and it struck down 29.25 per cent seedlings numbering 24,350 in one season. The cost of these seedlings was Rs. 535,700 (US $10,714 if Rs. 22.0 is considered as cost of one seedling) that being very substantial may discourage the grower to venture into the of poplar cultivation. So, disease management becomes imperative to prove economic viability of poplar cultivation. Disease is quantified in terms of prevalence, incidence and severity to assess the impact of the pathogen on the host. Limited reports of this nature are available in literature. They primarily measure either incidence or ENVIS Table 1. Major diseases in nurseries and plantations of indigenous species of poplars in India Host Fungus Distribution Reference Nursery P. alba Melampsora populina Uncinula salicis Uncinula adunca (Wallr) M. rostrupii; U. salicis (DC)Wint Cladosporium humile Davis Melampsora ciliata Barclay M. ciliata P. ciliata Venturia populina M. ciliata Botryodiplodia (Lasiodiplodia) palmarum M. ciliata C. humile M. ciliata Rhizotonia solani B.(Lasiodiplodia) palmarum P. gamblei Asteroma frondicola; C. humilie A. frondicola, Phyllosticta adjuncta Bub and Serebrianikow, U. salicis Septoria populi (Sacc.) Pollaccia elegans M. ciliata Alternaria alternata (Fr) Keissler Rosellinia necatrix Taphrina aurea M. ciliata P. suaveolens M. ciliata P. ciliata P. sauveolens, P. ciliata P. elegans Cytospora chrysosperma H.P. nursery Srinagar Social Forestry Division, (J. and K.) - Bakshi and Singh, 1967; Singh et al., 1983; Khan, 1988; Rehill et al., 1988 H.P. Singh and Singh, 1975 Kashmir Valley, Kamraj Forest Division, J. and K. Singh and Khan, 1981; Singh et al., 1983; Singh and Singh, 1986; Rehill et al., 1988; Sharma and Sharma, 2000 Singh and Singh, 1986 Ranikhet, Paharpani, U.P. and Solan and Shimla, H.P. H.P. nursery, Kashmir Valley Kashmir Valley, Palmpur and Bazaura nurseries, H.P. H.P. nursery J. and K. Kashmir Valley Kehmel Forest Division and Srinagar Social Forestry Division Gaja Nursery, U. P. and Jabalpur, Madhya Pradesh Kurukshetra Forest Division, Haryana and Sanjay Van, Tarai Central Forest Division, U.P. H.P. nursery Khan, 1988; Rehill et al., 1988 ; Khan, 1999; Sharma and Sharma, 2000 Kaul et al., 1989 Bakshi and Singh, 1967; Singh et al., 1983; Rehill et al., 1988; Khan, 1994, 99; Sharma et al., 2005 Bakshi et al., 1972; Singh et al., 1983; Khan, 1988 Singh and Singh, 1975 Singh et al.,1983; Rehill et al., 1988; Sharma and Sharma, 2000 Rehill et al., 1988 Singh and Singh, 1986; Mehrotra, 1992 Singh and Singh, 1986 Khan, 1988 H.P. nursery Khan, 1988 Kashmir Valley Kashmir Valley H.P. nursery - Rehill et al., 1988 Rehill et al., 1988; Kaul et al., 1989 Khan, 1988 Sharma et al., 1999 H. P. and U.P. H. P. North-eastern Himalaya nursery Plantation Kashmir Valley Kashmir Valley Khan, 1999 Sharma and Sharma, 2000 Viart, 1982 severity and that too in nurseries (Singh et al., 1983; Khan and Mishra, 1989; Singh et al., 1991; Sharma et al., 1999; Sharma and Sharma, 2000) with exception of plantations (Singh and Singh, 1986; Rehill et al., 1988). Singh et al. Forestry Bulletin, 12(1), 2012 Bakshi et al., 1972 Singh et al., 1983 Khan, 1999 Khan, 1999 (1983) recorded incidence of M. ciliata on different poplars in U.P. and H.P. nurseries and natural forest. In nursery, disease incidence ranged from 50 to 100 per cent on different clones while in forest it was 100 per cent on P. ciliata in U.P. 87 Table 2. Major diseases in nurseries of exotic species of poplars in India Host P. balsemifera P. deltoides Fungus U. adunca Schizophyllum commune Fr Phellinus pachyphleous (Pat.) Ganoderma lucidum Cortcium salmonicolor Berk & Br. Phaeoramularia maculicola (Rom. & Sacc.) B. palmarum Alternaria stage of Pleospora infectoria C. salmonicolor Alternaria sp., M. cilaiata, P. adjunct, B. palmarum, R. necatrix Cercospora populina M. ciliata Distribution J. and K. Western U.P. Tarai area of U.P. Phillaur, Punjab; East Dehradun Forest Division U.P. Reference Bakshi et al.,1972 Bagchee, 1960 Bakshi, 1971 Bakshi et al.,1972; Singh and Khan, 1981; Singh and Singh, 1986 Bakshi et al.,1972 Kashmir Valley Qasba et al., 1981 Haryana and U.P.; Lalkua Forest Research Nursery, U.P.; H.P. Central nursery Anantnag, Forest Division, J. and K. Garhwal Hills, U.P. H.P. Nursery Singh et al.,1983; Harsh and Kumar, 1997; Singh et al., 1983 Singh and Singh, 1986 Singh and Singh, 1986 Khan, 1988 Dreschlera maydis V. populina U.P. Kehmel Forest Division and Srinagar Social Forestry Division, H.P., U.P., J. and K.; Nauni, H.P. India Kashmir Valley Udit Narain, 1988 Rehill et al., 1988; Singh et al.,1983; Khan, 1994 Jones and Lal, 1989 Koul et al.,1989 Phoma macrostroma - Chuahan and Pandey, 1991 P. adjuncta - Singh et al., 1991 Bipolaris maydis U.P., Punjab and Haryana Chauhan and Pandey, 1992 M. larici-populina Kleb. Dun Valley Pandey, 1992 R. solani U.P. Singh and Singh, 1986 R. nectarix U.P., H.P. Khan, 1999 D. maydis Khan, 1999 A. alternata Payal, Haryana; Central Forest Tarai Division, U.P. H.P. Sclerotium rolfsii - Khan, 1999 M. roridum Dehradun, U.P. Khan, 1999 R. necatrix Shilli nursery Solan, H.P. Singh and Singh, 1986 Sun scald canker Singh and Singh, 1986 Curvularia lunata Tanda and Pipalparao Ranges of Tarai Central Forest Division, U.P. Punjab Ceratocystis sp. Doon Valley Pandey et al., 2002 Alternaria alternata (Fr.) Keissler (WSL39) B. setariae Shoemaker (1959) (Wimco A/49 x G3) B. specifera (Bainier) Subraman. 1971 (G48 x G3) Curvularia sp. (WSL22) Rudrapur, U.K. Singh et al., 2011 Rudrapur, U.K. Mishra, 2011 Rudrapur, U.K. Mishra, 2011 Rudrapur, U.K. Singh et al., 2011 Daldinia sp. close to D. eschscholzii (G48) Fusarium incarnatumequiseti complex (WSL39) Udam Singh Nagar, U.K. Singh et al., 2011 Rudrapur, U.K. Singh et al., 2011 Sharma et al., 1999 Gupta et al., 2001 Contd. on next page… 88 ENVIS ... Contd. from previous page Rudrapur, U.K. Singh et al., 2011 Rudrapur, U.K. Singh et al., 2011 Rudrapur, U.K. Singh et al., 2011 Rudrapur, U.K. Singh et al., 2011 Cercospora populina U.P. Bakshi et al, 1972 S. populi J. and K. Bakshi et al., 1972 U. adunca Sharma, 1985 U. populina J. and K. Kashmir Valley Kashmir Valley R. necatrix Gaja Nursery, U.P. Singh and Singh, 1986; Khan, 1988 C. humile H.P. Khan,1988 M. ciliata H.P. Khan,1988 P. eleagans Kashmir Valley Kaul et al.,1989 P. elegans J. and K. Khan and Mishra,1989 V. populina Kashmir Valley Koul et al.,1989 C. humile J. and K. Khan et al.,1990 P. regenerata U. adunca Kashmir Valley, J. and K. Bakshi et al., 1972 P. trichocarpa M. cilaiata H.P. Khan, 1988 P. x eumericana P. adjuncta H.P.; Dehradun, U.P. P. pachyphleous (Pat.) Tarai area of U.P. Sohi and Nayar, 1969; Rehill and Puri, 1980 Bakshi, 1971 Myrothecium roridum Tode ex Fr. S. populi Dehradun, U.P. B. palmarum U.P.; Kurukshetra Forest Division, Haryana; Sanjay Van, Tarai Central Forest Division U.P. Phillaur, Punjab; Tarai Cental Forest Division and Dehradun East Forest Division, U.P. U.P.; Dehradun East Forest Division, U.P. - Fusarium semitactum Berk. and Rav. (WSL39) Fusarium solani (Mart.) Sacc.(Wimco81) Nigrospora state of Khuskiya oryzae H. J. Huds ( G48) Rhizoctonia sp. (W22) P. nigra Ganoderma lucidum Cortcium salmonicolor Berk and Br. Phomopsis sp. Dehradun, U.P. Sharma, 1985 Bakshi et al., 1972; Rehill and Puri, 1980; Singh et al., 1991 Bakshi et al.,1972; Singh et al., 1991 Bakshi et al.,1972; Singh and Singh, 1986 Bakshi et al.,1972; Singh and Singh, 1986 Bakshi et al.,1972; Rawat, 1981; Singh and Singh, 1986 Bakshi et al.,1972 Bakshi et al.,1972 M. roridum Cooch Bihar and Kurseong Forest Division, West Bengal; New Forest , Dehradun Dehradun, U.P. G. lucidum Dehradun, U.P. Singh and Khan, 1981 Sphaceloma populi India Rehill and Puri, 1980 B. palmarum U.P.; H.P. Singh et al., 1983; Khan,1999 Macrophoma bengalensis Bakshi et al.,1972 Contd. on next page… Forestry Bulletin, 12(1), 2012 89 ... Contd. from previous page Sun scald canker P. yunnanensis M. cilaiata Tanda and Pipalparao Ranges of Tarai Central Forest Division, U.P. H.P. Singh and Singh, 1986 Khan, 1988; Sharma and Sharma, 2000 P. adjuncta H.P. Khan, 1988; Singh et al., 1991 Cercospora populina U.P. Chauhan and Pandey, 1991 Schizophyllum commune Fr Fomes (Phellinus) fomentarius (L.ex.Fr.) B. palmarum Western U.P. U.P. Hills Bagchee, 1960 Singh and Singh, 1986 R. nectarix Sanjay Van, Tarai Central Forest Division U.P. Gaja Nursery, U.P. M. ciliata H.P. Khan, 1988 Singh and Singh, 1986 Table 3. Major fungal diseases in plantations of exotic species of poplars in India Host Fungus Distribution Reference P. deltoides G. lucidum India B. palmarum Peepal Padav and Gangapur Patia plantations, U.P.; Haryana East Dehradun Forest Division, U.P. Kehmel Forest Division and Srinagar Social Forestry Division, J. and K. U.P. Kashmir Valley Kamraj and Baramulla Forest Division Kamraj, Langate and J.V. Forest Division Kashmir Valley East Dehradun Forest Division, U.P.; Pipal Padav, Belachaur and Gangapur Patia plantations, U.P.; Tanda block, Tarai and Bhabar Plantation Division, U.P. Bakshi et al., 1972; Singh and Khan, 1981 Rehill and Puri, 1980; Singh et al., 1983 Singh and Singh, 1986 Rehill et al.,1988 C. salmonicolar M. ciliata P. nigra P. x eumericana, P. noxius P. elegans, S. populi P. elegans S. populi P. elegans, S. populi C. salmonicolor B. palmarum, C. populina, Phomopsis sp., Poria vincta Tramotes corrugata M. bengalensis P. pachyphloecus H. P.; U.P. Khan, 1999 Khan, 1999 Rehill et al.,1988 Rehill et al.,1988 Khan, 1999 Singh and Singh, 1986 Rehill and Puri, 1980 Khan, 1999 Table 4. Incidence of different diseases in the poplar nursery in WIMCO R. and D. Centre, Rudrapur S. no. Disease Time of incidence Clone 1. 2. 3. 4. 5. 6. 7. Blister blight Blister blight Blister blight Blister blight Sclerotium leaf spot Sclerotium leaf spot Alternaria sp.* October 2009 October 2009 September 2010 September 2010 September 2010 September 2010 May 2012 Wimco32 Wimco81 Wimco81 Wimco83 G48 Wimco81 G48 Total no. of plants No. of plants died 17,758 5,604 980 3,920 536 980 83,250 165 8 17 192 6 12 24,350 Mortality (%) 0.93 0.14 1.73 4.90 1.12 1.22 29.25 *Alternaria appeared during extreme summer in June just after field planting of containerized plantlets in Bajpur nursery in District Udham Singh Nagar, Uttarakhand. only. Further, the disease severity was light to heavy in both nursery and stand (light = <30 per cent of foliage infected, moderate = 30-50 per cent and heavy = >50 per cent). Singh et al. (1991) reported foliar pathogens, P. adjuncta and M. roridum incidence on clones of P. deltoides and P. x eumericana in nursery of New Forest, Forest Research Institute, Dehradun. The incidence of the 90 disease was more in old nursery as compared to new nursery site. Sharma and Sharma (2000) conducted a survey on the disease status and distribution of foliar diseases of poplar in 1997-98 in polar growing areas under different agroclimatic zones of Himachal Pradesh. Seven fungal diseases were observed, viz., rust, M. ciliata; leaf spot, C. humile, A. alternate, S. populi, Sphaceloma populi; powdery ENVIS mildew, U. salicis and leaf blister, T. aures. The severity of diseases varied with place of survey which may be attributed to varying climatic conditions. Rust had highest mean disease severity of 34.36 per cent, Cladosporium leaf spot 16.60 per cent and powdery mildew with 14.80 per cent. Singh and Singh (1986) reported C. salmonicolor attack on various clones of P. deltoides and P. x eumericana (3.3 to 5.7 per cent) in five - and eleven-yr old plantations in east Dehradun Forest Division of U.P. Symptomatology The symptoms of 22 different diseases, (viz., Botryodiplodia palmarum, Alternaria sp., Cladosporium humili, Dreschlera maydis, Macrophoma sp. Phomopsis sp., Phyllosticta adjucnta, Pollaccia elegans, Septoria populi, Melampsora ciliata, Myreothecium roridum Rhizoctonia solani, Rosellina nectarix, Sclerotium rolfsii, etc.) have been described on exotics species namely, P. balsemifera, P. nigra, P. deltoides, P. x eumericana, P. regenerate, P. trichocharpa and P. yunnanensis. However, these symptoms lack matching photographic back up that becomes a critical limitation under two situations, one, the complex situation of symptoms of mixed infections under field conditions and two, access to discrete symptoms of the same disease on time scale leading to misconception about the complete sympotmatology of a particular disease. The Bipolaris blight has been used as an example to address these issues. The disease usually appears after onset of monsoon in late July. Pink to brown, pin head size spots develop on leaves (Fig. 1.Stage-1). Gradually, these enlarge into dark brown, irregular spots, often surrounded by a chlorotic margin (Fig.1. Stage-2). In rainy or humid weather, the irregular spots coalesce to cover the leaf blade that gave blighted appearance to the entire foliage (Fig. 4.2.1. Stage-3). Sometimes, the chlorotic spots were marginalized through midrib and veins giving a defined pattern of disease spread (Fig.1. Stage-4). Severely infected leaves crumble in dry weather and ultimately fall off prematurely (Fig. 2. Stage-5). Necrotic lesions, sometimes developing into sunken, black spot also appear on green pedicles and shoots (Fig. 4.2.2. Stage-6). Premature defoliation of the seedlings took place in short span of 3-4days. In case of nursery, the susceptible plants collectively provided burning appearance and in case of single plant, it stood conspicuously out of its green neighbours (Fig. 2.A). The symptoms were exclusively noticed on G3 clone of P. deltoides or generation having one of the parents as G3 (Fig. 2.B). The Causal Organism Practically, all the fungal pathogens belong to higher group of fungi irrespective of the origin of the host. They fall in Forestry Bulletin, 12(1), 2012 different categories, for example, most of them infect foliage (Alternaria sp., C. populina, P. adjuncta, M. roridum, S. populi, etc.) and some heart/root (G. lucidum); some cause leaf spot (A. alternata), blight (D. maydis), canker (C. salmonicolor), rust (M. ciliata); while some are wood rotter (F. fomentarius, P. pachyphleous), etc. Few new pathogens of P. deltoides were also reported namely, B. setariae, B. specifera, Daldinia sp., Fusarium incarnatumequiseti complex, Fusarium semitactum, Nigrospora state of Khuskiya oryzae, etc. (Mishra and Singh, 2011; Singh et al., 2011). Multiple species of the same genus, Bipolaris have been isolated from the G3 clone and its offsprings from the field. Few of them have been identified while some are still in the process. For example, based on r-DNA sequence analysis, isolate no. B58 and B29 had 99 and 96 per cent similarity with B. spicifera and B. setariae, respectively. Isolate no. B3 and B12 seem similar to B. spicifera while isolate no. B9, B18 and B48 were close to B. seteriae on the basis of morphological features namely, colony type and colour, conidiophore, conidum size and germination. Rest of the eight isolates appeared neither close to B. spicifera nor to B. setariae. It signifies that the initial pathogen, B. maydis of poplar has been completely replaced with these new species. Still, this observation needs further confirmation based on more extensive collection of isolates, culturing and identification at both morphological and molecular level (Mishra, 2011). One more issue of significance is that B. setariae and B. spicifera has wheat and grasses, respectively as hosts which, otherwise, are also a component of agroforestry systems. This line of observation reaffirms the old belief that B. maydis was transferred from maize to poplar as explained by Leonard (1987) that both P. deltoides and Zea mays have got the same gene centre- North America, regardless of their different botanical descriptions. This suggests that there is a co-evolution of host parasite interaction which are undetectable state under the natural ecosystems. However, when humans interfere the natural systems, epidemic appears due to strong selection pressure on the pathogen populations. In the present case, genetically susceptible male poplar cultivar G3 (Texas provenance) was vegetatively multiplied (uniform cytoplasm) in agroforestry systems in India which imposed strong pressure on the pathogen populations -B. maydis race T- which led to the development of devastative epidemics in the country. The new pathogen-host combinations require fresh explanation, though, physical closeness between the duos, survival option of the pathogen (new hosts), the shrinking distribution base of the susceptible clone, G3 and specificity 91 are some of the issues that may help in explaining the replacement of causal agent of blight with new but related species of Bipolaris. For example, as G3 clone was withdrawn from the cultivation during late 90s, it is probable that populations of B. maydis may have be replaced with other pathogens including species of Bipolaris due to lack of favourable food base (G3) of a pathogen that was already present in epidemic proportions. That is why, the isolations in the present study could not capture the original pathogen of blight, B. maydis. It is also important to go for molecular characterization of remaining unidentified isolates, so that, the complete structure of the pathogenic population of Bipolaris species can be elucidated as it will be important for resistance screening and development of promising poplar genotypes (Mishra, 2011). . Besides understanding the diversity of pathogens, it is also important to know the variations among the pathogenic populations from the point of view of breeding disease resistance. To capture this variability of potential pathogens, surveys of poplar nurseries in various states were conducted since 2006 (Singh et al., 2011). Table 5 reveals the status of pathogenic isolates collected from commercial clones of P. deltoides. During field trips, it was observed that A. alternata and Curvularia sp. are commonly present on practically all commercial clones, underlying their wide presence. These fungi are, otherwise, known to be weak pathogens but their universal appearance on all the clones may add to the widely believed fact that the climate change may affect the population structure of the pathogens under field conditions. Chakraborty et al. (2008) observed that changes in temperature and other climatic factors may activate some sleeper pathogen species while others may cease to be economically important. This may apply equally to endemic and exotic pathogens. Often minor changes in climatic factors such as temperature can tip the balance in favour of an exotic species for gaining a bridgehead following its inadvertent introduction. Unusual disease outbreaks could also occur from sporadic weather events. Variations among isolates of the pathogens (A. alternata, Bipolaris spp., Curvularia spp., Fusarium solani, Rhizoctonia spp., and Sclerotium rolfsii) were captured on various cultural and morphological parameters namely, colony type, pigmentation, rate of fungal growth, sporulation, spore size, colour and germination on different growth media (PDA, CDA, MEA, SPA, etc.; Bagwari, 2009; Swati, 2009; Bagwari et al., 2010; Panwar, 2010; Geetanjali, 2010; Geetanjali et al., 2011; Gupta, 2011, Gupta et al.,2011; Panwar et al.,2011, Mishra, 2011; Vadeo, 2012; Upadhyay, 2012 ). Moreover, fungicidal and biogenic (fungi, bacteria and amongst isolates) sensitivity was also quantified. The growth of different isolates of pathogens showed differential trends over time. The matrix between growth media vis-à-vis cultural and morphological characters help in resolving the differences among the isolates of a pathogen. The disease development under field condition must be an outcome of various factors- the inherent capacity of the pathogen for causing disease (virulence/aggressiveness, inoculum potential, etc.) besides competition from the other contemporary pathogens, etc. Two experiments were carried out under laboratory conditions to understand the interactions between Bipolaris spp. and A. alternata (that occupies same time and space (foliage) as pathogen) and within population of Bipolaris spp. isolates. These isolates had differential interactions with isolates of another pathogen, A. alternata (as antagonist). Minimum efficacy of A. alternata had been against isolate no. B29 (-5.8 per cent) and maximum against isolate no. B48 (32.2 per cent). This indicates the presence of mutual antagonism between the two fungi. The interaction among isolates of Bipolaris spp. registered different trends with changing isolate in the Table 5. Isolates of fungal species collected from clones of P. deltoides from different states of India Fungus Bipolaris spp. Alternaria alternata Clone G3 and off springs G3, G48, WSL22, WSL39, Udai Phoma/ Phyllosticta sp. WSL22, Udai 30 Curvularia spp. G48, WSL22, Udai 70 Sclerotium rolfsii WSL31, WSL39 Rhizoctonia sp. Fusarium solani WSL22 Wimco81, Wimco83 92 No. of isolate 130 >100 >100 20 15 Place Rudrapur (U.K.) Thana Chappar (Haryana), Paniyala and Maheshwari (Roorkee) and Rudrapur (U.K.) Rudrapur and Paniyala (Roorkee; U.K.) Thana Chappar (Haryana), Paniyala and Maheshwari (Roorkee) and Rudrapur (U.K.), Sharanpur (U.P.) Jawahar Nagar, Rudrapur and Maheshwari (U.K.) Rudrapur (U.K.) Rudrapur (U.K.) Year of collection 2006-12 2007-12 2008-2009 2008-12 2008-11 2011 2011 ENVIS interaction. For example, isolate no. B29 could suppress isolate no. B40 (38.1 per cent) and isolate no. B48 (38.4 per cent) establishing its better competitiveness (Mishra, 2011). Pathogen Survival According to Dickinson and Lucas (1982) whenever pathogens are not sheltered by a host they face problems of survival in a hostile environment. The extent of this problem for any particular pathogens depends on the length of the period between hosts and the relative hostility of the environment. At one extreme, dispersal during epidemic spread may involve only brief periods when spore or other propagules are away from their hosts. On the other, pathogens survive between annual crops planted in successive growing seasons or in rotations when suitable hosts are available only every third, fourth or even fifth year. In the intervening periods, environmental extremes jeopardize the pathogen’s chances of survival. Drought, water logging and extremes of temperature can all reduce the viability of dormant pathogen’s future inocula; these surviving structures are also subject to microbial antagonism which can severely debilitate or even destroy them. Mishra and Khan (1991) discussed the disease development and pathogen survival of Sclerotium leaf spot of poplars. The source of infection was attributed to sclerotia produced on the infected plants of the previous year and leaf litter. Such information for other pathogens are conspicuously missing in literature. Management of Diseases The chemical management of poplar diseases was generally tried in the nurseries. In vitro testing of the chemicals has also been attempted. Biological management of the diseases is rare like that of cultural. Similarly, breeding for disease resistance is also an exception than rule. Singh and Singh (1986) recommended several cultural practices to manage Ganoderma root rot, for example, mix planting of deciduous species like semul (Bombax ceiba) and kanju (Pongamia pinnata) with poplar in order to break the continuity of Ganoderma infection in the event of the diseases outbreak in plantations. Further, disease in poplar plantations can be managed by removing roots and stumps of previous crop from the site before raising poplar plantations. Spread of the disease in lines can be checked by increasing spacing in between plants in lines, isolating the disease patches by digging 0.7m deep and 0.3m wide trenches from the healthy plants. They also suggested the management of Rosellinia root rot- the affected plants should be uprooted and destroyed, the infected area of the nursery should not be Forestry Bulletin, 12(1), 2012 replanted for one season, the disease from the soil can be eradicated by treatments of the soil with carbon disulphide or 5 per cent solutions of carbolic acid and drenching of soil around affected plants with 0.1 per cent Bavistin was also found effective to check the disease. Sharma and Bhardwaj (1989) suggested pruning out of weak, dead and canker affected branches, and sweeping of the nursery floor and burning of the leaves after leaf fall to manage the canker disease. Khan (1999) also recommended sanitation of planting site, proper spacing and isolation trenches for the management of diseases in poplar plantations. Experiments were conducted in the nursery (20062008) on effect of time of planting and of weeding on the growth and disease status of poplar clone like G-48. Growth as well as disease was quite low in June transplanted G-48 clone of time of planting experiment. However, in 2008 experiment of similar nature, the trends were not so discrete especially with regards to disease. The rains in tarai region of Uttarakhand were started in late June and had a persistent trend over the entire monsoon period. It must have helped the disease initiation at a very early stage of the monsoon. However, due to consistently heavy rains over a long period (June to September 2008), the spread of the disease and its sustenance was affected reflecting a dip in the second stage of observation and, there after, an increase owing to receding rains and high atmospheric moisture (Singh et al., 2011). Further, impact of the cultural practice, weeding on growth and disease development was also attempted. It can be concluded that moderate weeding to the tune of 15 days may match with the frequent weeding of five days gap both in terms of growth as well as foliar infection. Such information are vital for cutting the cost of nursery operations affecting cost-benefit ratio for a commercial crop like poplar which may be offered as a alternative model of agri-silviculture to agriculture. Different group of fungicides (systemic and nonsystemic) were screened in the laboratory against varied poplar pathogens (Curvularia sp., Drechslera spp., F. solani, Rhizoctonia sp., etc.). The systemic fungicides, Benomyl and Propiconazole were found very effective against the isolates of S. rolfsii species. The isolate sensitivity to Benomyl was quite apparent at the lower dose of 10 ppm while in case of Propiconazole, no growth was recorded even at the lowest concentration of 5 ppm (Gupta, 2011). Chemical management of poplar diseases is more attempted for two pathogens; i.e., rust (M. ciliata) and set rot (B. palmarum; Table 6). The former has wider presence on the indigenous poplars (Table1) leading to more attention for its management. The set is the basic unit for the vegetative 93 Table 6. Chemical management of poplar diseases Pathogen C. salmonicolor M. ciliata Chemical/ Dose/ Interval 0.2% Dithane-M-45 + 0.1% Bavistin (spray) Copper oxychloride (0.2%)/ fort night; Bavistin (0.1%) or combinations of calixin (0.075%) + Dithane-M-45 (0.15%) /three sprays/20 days intervals; 0.1% Bavistin; Nurseries/ six sprays/ fort night/ Bavistin 0.1% spray at fortnightly interval Cyproconazole(0.03%) or Triadimefon (0.05%) at two weeks intervals; Penconazole best (35.48% disease). Reference Singh and Singh, 1986 Singh et al., 1983; Khan 1988 & 99; Rehill et al., 1988 Khan,1994; Sharma et al., 2005 R. solani Blitox, Captan and Thiram @ 20-50g/m2 (drenching) Singh and Singh, 1986 C. humile 0.4% Dithane-M-45 (spray); 0.25% Dithane-M-45 + Bavistin 0.5% of mercury fungicide (dip for 15 min.) 0.35% DithaneM-45; 0.03% DithaneM-45; 0.05% Benomyl 0.2% Dithane-M-45 or any copper oxychloride fortnightly spray Dithane-M-45 or Dithane- Z-78( 100 g/m2/drenching) Singh and Singh, 1986; Khan, 1988 B. palmarum U. salicis R. necatrix M. ciliata, S. populi D. maydis 0.2% DithaneM-45 Dithane -M-45 and Bayleton propagation of poplar and any health problem may draw immediate attention for its management. The biological control of plant pathogens is gaining importance owing to the non- targeted effects of pesticides, environmental pollution due to indiscriminate use of agro chemicals and development of resistance in pathogens to the pesticides, etc. There are few reports regarding use of antagonist (bio-control agent) against poplar pathogens (Bipolaris spp., Curvularia sp., etc.). In case of Curvularia sp., it was observed that only one isolate (no.7) exhibited suppression in the presence of antagonist (12.3) while other isolates of fungi remained unaffected (Pooja, 2010; Pooja et al., 2011). The antagonist (Pseudomonas sp.) failed to suppress the pathogen due to presence of haloperoxidase of the pathogen that adversely affected the former. Further, it may also be attributed to the different niche occupied by the fungal isolates (foliage-borne) and antagonist (soil-borne) leading to lack of real life interactions. Trichoderma sp was also tested against isolates of Fusarium sp., Rhizoctotia solani, and S. rolfsii. The antagonistic interactions between Trichoderma species and S. rolfsii revealed one interesting fact that antagonist was able to suppress all the isolates within a close range of 48 to 57 per cent barring isolate no. 2 (79.0 per cent) which had a suppression significantly more than other nine isolates of Sclerotium species (Gupta, 2011). Different studies were conducted to screen poplar genotypes against various diseases (Harsh and Kumar, 1997; Sharma et al., 1999; Mishra, 2011). Nineteen clones of 94 Singh and Singh, 1986 ; Rehill et al., 1988; Khan et al., 1990 Sharma and Sharma, 1997 Singh and Singh, 1986 Khan,1988 Rehill et al., 1988 Khan, 1999 P. deltoides were screened against set rot (B. palmarum). The study revealed that S7C8 clone was most resistant followed by TRI- T-19, S7C15, PDA/1945, S7C20 and L188:89. On the other hand, most susceptible clone was L52/88 followed by PD-3201 (Harsh and Kumar, 1997). An experiment was conducted to assess resistance of poplar germplasm against A. alternata in Nauni nursery, H.P. and reported 5 per cent incidence of disease on three clones (Delcnat-4, Narkanda and Chamba) and two hybrids (165M2 and 2M2) of P. ciliata. Also, five clones of UHF selections (P2/92, P6/92, P9/92, 96-1, 2PC); four clones of Lalkuan selections (1L-3B, 1L-4B, 1L- 8, 3L-2B) and two hybrids (HybB and Hyb3) showed disease symptoms (Sharma et al., 1999). Mishra (2011) screened seven commercial clones of P. deltoides, namely, G3, WSL 22, WSL39, G48, Udai, S7C8 and S7C15 against B. spicifera. Barring WSL-39, all the clones exhibited symptoms of blight. Besides screening of genotypes, the crude toxin of Bipolaris species were tested against shoot juveniles and root cuttings of G3 clone of P. deltoides (Fig. 3). It was observed that out of the sixty isolates tested, six isolates (B2, B4, B19, B31, B32, and B34) were more aggressive in comparison to others as they initiated blight symptoms earliest after 3hrs on shoot juveniles. While, isolate B16 and B18 could produce blight after 6h. Most of the aggressive isolates (B2, B19, B31 and B32) exhibited 100 per cent foliage blight. While, isolates like B18 and B45 exhibited wilting symptom within 3h. Blighted symptom was also expressed ENVIS Fig. 2. Various stages of blight development on the poplar foliage (Stage 5) and shoot (Stage 6) in nursery. Fig.1. Various stages of blight development on the poplar foliage in nursery. Fig. 3. Stage I: Symptoms produced by crude toxin on shoot juveniles of G-3 clone. AB) Initial to mild flecking on leaf, C) blightening of leaf blade with prominent blackening of veins, D) inter-veinal blight, E) blightening of leaf from margin in wards, F) completely blighted shoot juvenile and G) shoot blight. Forestry Bulletin, 12(1), 2012 Fig. 4. Steps of in-vitro testing of the fungal toxin. A. Leaf of G-3 control (with drop of sterilized distilled water) and B. Toxin treated leaf (with drop of toxin at the centre. 95 within the same observation period by isolates like B43 and B50. Similar symptoms were observed with leaf bioassay of pure toxin (Fig. 4). Similarly, Chauhan and Pandey in 1995 carried out physiological identification of B. maydis race T pathogenic to P. deltoides. Toxin metabolites were isolated by chloroform extraction. Presence of toxin in the solution was detected by using a leaf disc bioassay leaf discs floated 500 to 1,000 ppm concentrations exhibited about cent per cent necrosis within 12 to 15 hour of incubation. At 100 ppm, necrosis was very slow but at 10 ppm only flacking was recorded. Toxin is known to be produced by race T but not by race O. In this study, only P isolate produced the toxin in the culture medium which was detected by host sensitivity test in which susceptible poplar cultivars-G3 and 111101 exibited necrosis. All the isolates of Bipolaris spp. could initiate pathogenic reaction in G3 clone but to varying degrees. Pathogenic reactions were more prominent and swift in shoot juvenile in comparison to stem cutting probably due to direct sucking of the cultural filtrate in the vascular tissues in the former. While in case of stem cutting, the uptake of the filtrate was through roots that took longer route to reach the leaves. Moreover, the hardening of the tissue in cuttings may be another impediment of early expression of the severity of the symptoms. During night, the appearance of pathogenic reaction was quite slow as transpiration rate is less due to low night temperature. In absence of a strong pull the uptake of liquid (water and filtrate) through vascular tissues is also slow that, in turn, may slow down the distribution of the toxin in the foliar part and accordingly its effect in symptom expression like wilting and blightening. Poplars occupy a unique and important position in the rural economy of India. Users including farmers have fully appreciated the benefits of poplar cultivation and consider poplar tree as assets for the future needs. It is only possible when they get constant supply of the healthy planting material through assured quality control including disease free seedlings. High cost and even impossibility of direct chemical control and the uncertainty of biological management indicate the necessity for developing pest resistant forest trees. It is possible only through the screening of the promising germplasm for disease resistance. The field evaluation of important diseases, understanding of the biology of the pathogens especially their disease cycle, development of quick methods for the resistance screening (toxin bioassay, etc.) are some of the approaches that will contribute towards the culture of poplar. 96 References Bagchee, K. 1960. Pathology of Kashmir Forest - A survey and review of the problems and methods of protection. Dehradun, FRI and C. 85p. Bagwari, A. 2009. Morphological and cultural variations among isolates of Drechslera sp.of poplar. M.Sc. thesis. Gurukul Kangri University, Haridwar. 43p. Bagwari, A.; Singh, Y.P.; Mishra, S.; Singh, R. and N. Singh. 2010. Morphological and cultural variations among isolates of Drechslera sp. of poplar. In: International Conference on Mountain Diversity and Sustainable Development, Dehradun, 13-15 March 2010. Abstracts. Dehradun, Doon University. p.40 Bakshi, B.K. 1976. Forest pathology: Principles and practice in forestry. Delhi, Controller of publications. 400p. Bakshi, B.K. 1971. Indian Polyporaceae on trees and timber. New Delhi, Indian Council of Agriculture Research. 46p. Bakshi, B.K. and Singh, S. 1967. Rust on Indian forest trees. Indian Forster Records (NS), 2(8): 139-204. Bakshi, B.K.; Reddy, M.A.R.; Puri, Y.N. and Singh, S. 1972. Disease survey (final technical report). Forest Pathology Branch, FRI, Dehradun. 117p. Bishir, J. and Roberds, J.H. 1999. The numbers of clones needed for managing risk in clonal forestry. Forest Genetics, 6(3): 149-155. Chakraborty, S.; Luck, J.; Hollaway, G.; Freeman, A.; Norton, R.; Garrett, K.A.; Percy, K.; Hopkins A.; Davis, C. and David Karnosky, F. 2008. Impacts of global change on diseases of agricultural crops and forest trees. CAB Reviews: Perspectives in Agriculture, Veterinary Science, Nutrition and Natural Resources, (3) No. 054. [Available at: http://www.cababstractsplus.org/ cabreviews]. Chandra, J. P.; Gandhi, J.N. and Joshi, B.C. 2001. Clonal trail on Populus deltoides in Tarai region of Uttaranchal. Indian Forester, 127 (2): 257-259. Chauhan, S. and Pandey, B.N. 1991. Cercospora populina and Phoma macrostroma causing foliage diseases of Populus deltoides. Indian Phytopathology, 44(4): 549-551. Chauhan, S. and Pandey, B.N. 1992. A new leaf blight of Populus deltoides caused by Bipolaris maydis. Indian Phytopathology, 45: 130-33. Chauhan. S. and Pandey, B.N. 1995. Identification of Bipolaris maydis race T-pathogenic to Populus deltoides. Indian Phytopathology, 48(1): 55-60. ENVIS Dhiman, R.C. 2007. Infestation of leaf curl mite (Tetranychs urticae Koch) in poplar nurseries. ENVIS Forestry Bulletin , 7(2): 132-138. Dhiman, R.C. 2012. Diagnosis of intercrops in poplar based agroforestry. Indian Forester (Accepted). Dickinson, C.H. and Lucas, J.A. 1982. Plant pathology and plant pathogens. 2nd ed. Oxford, Blackwell Scientific Publications. pp. 51-53. Geetanjali. 2010. Biological control properties of fluorescent pseudomonads of G-48 clone of Populus deltoides. M.Sc. thesis. Gurukul Kangri University, Haridwar. 50p. Geetanjali; Singh, Y.P.; Singh, P. and Das, S. 2011. Fluorescent pseudomonads of Populus deltoides: Potential tree health agents. In: National Seminar on Forest Health Management, Coimbatore, 21-22 March 2012. Abstracts. Coimbatore, IFGTB. p.126. Gupta, A. 2011. Morphological and cultural variations among isolates of Sclerotium sp. of poplar. M.Sc. thesis. Dolphin (P.G.) Institute of Bio-Medical and Natural Sciences, Dehradun. 51p. Gupta, A.; Panwar, P.; Bagwari, A.; Uniyal, K.; Kavita; Singh, Y.P.; Dhiman, R.C. and Gandhi, J.N. 2011. Morphological and cultural variations among isolates of Sclerotium rolfsil of poplar. In: National Seminar on Forest Health Management, Coimbatore, 21-22 March 2012. Abstracts. Coimbatore, IFGTB. 105 p. Gupta, A.K.; Khera, H.S. and Singh, S. 2001. Incidence of leaf spots of poplar in three agro-climatic zones of Punjab. Plant Disease Research, 16: 134-136. Harsh, N.S.K. and Kumar, P. 1997. Screening for resistance against set-rot and mortality in poplar cuttings. Indian Forester, 123(3): 262-63. Heybroek, H.M. 1978. Primary considerations: Multiplication and genetic diversity. Unasylva, 30(119-120): 27-33. Hull, R.B., and Gobster, P.H. 2000. Restoring forest ecosystems: The human dimension. Journal of Forestry, 98(8): 32-36. Jones, N. and Lal, P. 1989. Commercial poplar planting in India under agroforestry system. Commmonwealth Forestry Review, 68: 19-26. Kaul, A.K.; Ghani, M.Y. and Kaul, R.N. 1989. A new scab disease of poplar from India. Plant Disease Research, 4(2): 187-188. Khan, S.N. 1988. Diseases of poplars in nurseries of Himachal Pradesh. In: Meeting of FRI Scientists with H.P. Forest Officers, Shimla, September 1988. Proceedings. Forestry Bulletin, 12(1), 2012 Khan, S.N. 1999. Principal diseases of poplars in India and their management. In: National Seminar on Poplar, Dehradun, 25-27 November 1999. Proceedings. Dehradun, Forest Research Institute. pp. 1-9. Khan, S.N. and Misra. B.M. 1989. Pollaccia blight of poplars in India. Europian Journal of Forest Pathology, 19: 379-81. Khan, S.N.; Rehill, P.S.; Tiwari, R.K. Rawat, D.S. and Mishra, B.M. 1988. Control of poplar rust, Melampsora ciliate in nurseries. Indian Forester, 11(3): 253-255. Khan, S.N.; Tiwari, R.K. and Misra, B.M. 1990. A calendar for foliage diseases of poplars in Himachal Pradesh nurseries and their management. Indian Journal of Forestry, 13(1): 41-42. Khan, Y. 1994. Studies on Melampsora leaf rust of Populus species. M.Sc. thesis, Dr. Y.S. Parmar University of Horticulture and Forestry, Nauni. Kishwan, J. and Kumar, D. 2003. Future of poplar in India. In: First International Conference on Future of Poplar Culture, Rome, 13-15 November 2003. Papers. Rome, National Poplar Commission of Italy and FAO. Leonard, K. J. 1987. The host population as a selective factor. In: Wolf, M.S. and Caten, C.E. Eds. Populations of plant pathogens: Their dynamics and genetics. Oxford, Blackwell Scientific Publications. pp. 163179. Libby, W.J. and Ahuja, M.R.1993. Micropropagation and clonal optios in foressty. In: Ahuja, M.R., Ed. Micropropagation of woody plants. Dordrecht, Kluwer Academic Publisher. pp. 425-442. Mishra, A.; Swamy, S.L.; Bargali, S.S. and Singh, A.K. 2010. Tree growth, biomass and productivity of wheat under five promising clones of Populus deltoides in agri-silviculture system. International Journal of Ecology and Environmental Sciences, 36(2-3): 167-174. Mishra, S. 2011. Disease status and their management of poplar nurseries in Northern India. Ph.D. thesis. Forest Research Institute Deemed University, Dehradun. 148p. Misra, B.M. and Khan, S.N. 1991. Sclerotium leaf spot and stem rot of poplars. Indian Forester, 117 (8): 618-20. Naraina, U. 1988. Some additions to Indian Cerosporaea. Farm Science, 1(3): 36-39. NPC (India. National Poplar Commission). 2012. Country report on poplars and willows. Dehradun, Indian Council of Forestry Research and Education. 61p. [Available at: http://ipc2012.icfre.gov.in/ c_p_report.php]. 97 Pandey, A. 2002. Studies on disease resistance of newly introduced germplasm (progenies of Populus deltoides). Final project report submitted to Forest Research Institute, Dehradun. 40p. Pandey, P.C. and Khan, S.N 1992. Disease status of poplars in India. In: 19th Session of the International Poplar Commission, Zaragoza, 22-25 September 1992. Proceedings. IPC. pp. l- 7. Panwar, P. 2010. Studies on leaf spot disease (Curvularia sp.) of poplar. M.Sc. thesis. H.N.B. Garhwal University, Srinagar. 59p. Panwar, P.; Singh, Y.P.; Mishra, S.; Uniyal, K. and Singh, R. 2011. Antagonist efficacy of Pseudomonas sp. against Curvularia sp. of poplar. In: National Seminar on Recent Advances in Fungal Biotechnology, Dehradun, 22-23 September 2011. Abstracts. Dehradun, Forest Research Institute, Dehradun. p. 65. Qasba, G.N.; Dar, G.N. and Shah, A.M. 1981. Two unrecorded plant disease in India. Indian Phytopathology, 34: 390-392. Rawat, B.S. 1981. Pest and disease of poplar plantations in U.P. Tarai. In: Symposium on Silviculture, Management and Utilisation of Poplars, Srinagar, 15-18 October 1979. Proccedings, edited by R.V. Singh. Delhi, Controller of Publications. pp. 126-129. Rehill, P.S. and Puri, S.N. 1980. Some important diseases of poplars. Indian Journal of Forestry, 2: 176-83. Rehill, P.S.; Khan, S.N.; Tiwari, R.K.; Rawat D.S. and Misra, B.M. 1988. Control of poplar rust Melampsora ciliata in nurseries. Indian Journal of Forestry, 2(1): 77-79. Rehill, P.S.; Khan, S.N; Tiwari, R.K. and Mishra, B.M., 1988. Potentially important foliage diseases of poplars in Kashmir Valley. Indian Journal of Forestry, 11(4): 316-318. Schreiner, E.J. 1965. Maximun genectics improvement of forest trees through synthetic multiclonal hybrid verities. NE Forest Tree Improvement Conference, 1965. Proccedings. pp. 7-13. Sharma, A.K. 1985. A new species of Uncinula (erysiphaceae) from Kashmir. Current Science, 54:237-239. Sharma, R.C. 2009. Poplar diseases in India and their management. ENVIS Forestry Bulletin, 9(1): 87-99. Sharma, R.C. and Sharma, S. 2000. Status and distribution of foliar disease of poplar in Himachal Pradesh. Indian Phytopathology, 53 (1): 57-60. Sharma, R.C.; Sharma, S. and Gupta, A.K. 2005. Effect of preventive fungicides sprays on Melampsora rust of poplar in nurseries. In: Pei, M.H. and McCracken, 98 A.R. Eds. Rust disease of willow and poplar. London, CAB Publishing. pp. 209-212. Sharma, R.C.; Sharma, S. and Khurana, D.K. 1999. Assessment of poplar germplasm for resistance against Alterneria alternata causing leaf spot of poplar in Himachal Pradesh. Indian Forester, 125: 784-787. Sharma, R.C.; Sharma, S. and Khurana, D.K. 1999. Assesment of poplar germplasm for resistance against Alternaria alternata causing leaf-spots of poplar in Himachal Pradesh. Indian Forester, 125: 784-787. Singh, P. and Singh, S. 1975. Inscet pest and diseases of poplars in developing countries. In: Second World Technical Consultations on Forest Diseases and Insects, New Delhi, 7-12 April 1975. Proceedings. Singh, P. and Singh, S. 1986. Insect-pests and diseases of poplars. Dehradun, Forest Research Institute. 74p. Singh, S. and Khan, S.N. 1981. Impact of diseases on success of poplar plantations in India. In: Symposium on Silviculture, Management and Utilization of Poplar, Srinagar, 15-18 October 1979. Proceedings, edited by R.V. Singh. Delhi, Controller of Publications. pp. 139- 141. Singh, S., Pandey, P.C., Singh, A., Bahadur, R. and Mukharji, S.N. 1991. Studies on foliage diseases of poplar. Indian Forester, 117: (2): 135-142. Singh, S.; Khan, S.N. and Mishra, B.M. 1983. Some new and noteworthy disease of poplar in India. Indian Forester, 109(9): 636-644. Singh, S; Pandey, P.C.; Singh, A.; Bahadur, R. and Mukherjee, S.N. 1991. Studies on foliage disease of poplars. Indian Forester, 117: 135-142. Singh, Y.P.; Kumar, A.; Singh, N. and Mishra, S. 2011. Identification and evaluation of disease resistance in different genotypes of poplar. Project completion report submitted to Indian Council of Forestry Research and Education, Dehradun.190p. Sohi, H.S.; Nayar, S.K. 1969. New records of fungi from Himachal Pradesh-III. Indian Phytopathology, 22: 462-465. Stelzer, H.E. and Goldfarb, B. 1997. Implementing clonal forestry in south eastern United States. Canadian Journal of Forest Research, 27: 442-446. Swati. 2009. Studies on leaf spot disease (Phoma/Phyllosticta sp.) of poplar. M.Sc. thesis. Ch. C.S. University, Meerut.70p. Talbert, C.B.; Ritchie, G.A. and Gupta, P. 1993. Conifer vegetative propagation: An overview from commercial persepective. In: Ahuja, M.R. and Libby, W.J. Eds. Clonal forestry I. Genetics ENVIS and biotechnology. Berlin, Springer-Verlag. pp. 145-181. Tewari, J.P. 1983. Cellular alterations in the blackspot of rapeseed caused by Alternaria brassicae. Phytopathology, 73: 831. Upadhyay, S. 2012. Studies on variability among isolates of Rhizoctonia sp. of poplar. M.Sc. thesis. Doon (P.G.) College of Agriculture Science and Technology, Selakui, Dehradun. 70p. Vadeo, D.A. 2012. Studies on diversity among isolates of Fusarium solani causing stem canker diseases of Forestry Bulletin, 12(1), 2012 poplar. M.Sc. thesis. Baba Farid Institute of Technology and Science, Dehradun. 65p. Viart, M. 1982. Usefullness of forest genectics to extension of poplar farming in India. Journal of Forest Science, 1(1-2): 8-16. Zobel, B.J. and Ikemori, Y.K. 1983. Vegetative propagation in eucalypts. In: 19 th Meeting Canadian Tree Improvement Association, Toronto, 1983. Clonal forestry: Its impact on tree improvement and our future forests - Proceedings, edited by L. Zsuffa, R.M. Rauter and C.W. Yeatman. The author. pp. 136-144. z 99 Fungal Decay in Poplar Trees and Wood N.S.K. Harsh Forest Pathology Division, Forest Research Institute, Dehradun - 248 006 Introduction P The poplar wood has oplar (Populus deltoides) is an ideal tree for agroforestry and farm forestry in North India. Indigenous poplars grow in the Himalayas whereas P. deltoides have been introduced on the farm land in the plains of Punjab, Haryana, Uttarakhand and Uttar Pradesh. The tree has become an integral part of the agri-ecosystem and play an important role in local, state and national economy. Initially, poplar farming was introduced to meet the demand of match industry but now poplar wood is extensively used in making plywood and many other products. Presently, the plywood industry is the main consumer of poplar wood. Yamunanagar in Haryana is the main poplar wood trading and processing centre in the country, where demand of about 300 plywood industrial units exceeds the supply. Farmers are the main growers of poplar to meet this demand. Poplars have changed the landscape of this region and also contributed in tree cover of the country. Besides plywood, poplar wood has uses in making packing cases, matchsticks, ice cream spoons, etc. Poplar wood is not used for making furniture and doors and windows because of the mindset that it is soft and not durable. However, studies have revealed that the poplar wood has varying durability and natural decay resistance and therefore, can be safely used for furniture and doors and windows making (Harsh et al., 2009). Poplar trees and wood are attacked by wood decaying fungi in field and during storage. An account of fungal decay in poplar (P. deltoides) and natural decay resistance is being given below. Fungal Decay in Living Trees varying durability and natural decay resistance, however, poplar trees and wood are attacked by wood decaying fungi in field and during storage 100 Root Rot Root rot in poplar trees is caused by Ganoderma lucidum (Curtis:Fr.) P. Karst. (Fig. 1a) The affected trees exhibit drying of branch tips when the root system is decayed by the fungus. Young trees of 2-3 years die fast from top downwards. The older trees may uproot during storms and heavy rains due to rotting of anchoring roots. The fruiting bodies develop during the rainy season at the base of the trees which are with a dark brown shiny stipe and ENVIS reddish brown laccate cap. G. lucidum has been reported to cause 100 per cent mortality in poplar plantations in Phillaur, Punjab. Heart Rot and Canker Rot Phellinus pachyphloeus (Pat.) Pat. (=Fomes pachyphloeus (Pat.) Bres.) causes heart rot in older poplar trees (Fig. 1b). The trees become hollow within and the decay extends into sapwood making the trees vulnerable to wind breakage. The fungus enters the trees through wounds caused due to tractor movement and sunscald injuries on the stem. The heartwood development seldom takes place in young poplar which is harvested early. However, when poplars are retained longer especially in avenues and for breeding programmes, P. pachyphloeus infection may take place. Singh and Singh (1986) have reported this infection in Tarai region of Uttarakhand (in erstwhile Uttar Pradesh). Fomes fomentarius (L.: Fr.) Fr. causes heart rot of P. nigra trees on roadside in Kashmir (personal observation during 2012 visit; Fig. 1c). The heart rotted trees snap during storms. Singh and Singh (1986) have reported F. fomentarius in Populus yunnanensis and P. ciliata trees in Kumaun Hills of Uttarakhand. Singh and Singh (1986) reported Earliella scabrosa (Pers.) Gilb. & Ryv. (=Trametes corrugata (Pers.) Bres.) causing heart rot in 10-yr old trees of P. x euramericana in Tarai region of Uttarakhand. Harsh (2008) reported it from Lalkua (Nainital), Uttarakhand in P. deltoides (L-series; Fig. 1d). Wood Decay in Storage Poplar wood decays fast by wood decaying fungi while in storage. Mostly it is attacked by white rot fungi. The common white rot fungi reported by Harsh (2008) on stored poplar wood are: Daldinia concentrica (Bolt.) Ces. & De Not. (Fig. 1e), Lenzites acuta Berk., Pycnoporus sanguineus (L.: Fr.) Murr. (Fig. 1f) and Pleurotus spp. Singh and Singh (1986) have reported Oxyporus populinus (Fr.) Donk (=Fomes connatus (Weinm.) Gill. on stumps and roots of Populus spp. in Chakrata and Mussoorie in erstwhile Uttar Pradesh (now in Uttarakhand) and Polyporus squamosus Fr. on dead stem of Populus spp. in Manali, Himachal Pradesh. Natural Decay Resistance of Poplar Wood The information regarding the natural decay resistance in commercially grown poplar clones was first time brought out Forestry Bulletin, 12(1), 2012 in India by Harsh (2008). It is a misconception that poplar wood is not durable, however, the study conducted at Forest Research Institute, Dehradun revealed otherwise. The study revealed that there is definite variation among the clones/ source material of poplar for decay resistance; even within same clone of different locations and some clone exhibited natural decay resistance. Thirty-nine samples of 16 clones of P. deltoides were collected from the states of Haryana, Punjab, Uttar Pradesh and Uttarakhand and subjected to accelerated laboratory tests (Bakshi et al., 1967) to assess natural decay resistance in them using one white rot test fungus Pycnoporus sanguineus and one brown rot test fungus Gloeophyllum striatum. The wood blocks were categorized on the basis of weight loss in four resistant classes; i.e., highly resistant (010 per cent wt. loss), resistant (11- 25 per cent wt. loss), moderately resistant (26-44 per cent wt. loss) and non-resistant (above 45 per cent wt. loss; Table 1). Most of the tested poplar clones showed resistance against brown rot fungus. Brown rot fungi are more confined to higher altitude temperate regions and from the findings, it can be suggested that poplar (P. deltoides) wood can be safely used for construction and furniture making at high altitudes. It was also revealed that unlike most traditional timber species, heartwood of poplar is more susceptible to decay fungi than sapwood. This quality can be used while peelings are made for plywood manufacturing. Leaving a central core of inner-wood would give a decay resistant material. The materials assessed for natural decay resistance were obtained from trees of different age groups starting from 4.5 years to 16 years, but age of trees was not found to show any relation to decay resistance as the wood from 4.5 years of tree was found in the same resistant class as from the tree of 16 years of age. Similarly, wood samples from the trees of 5-7 yrs of age showed wide variation in decay resistance from Class I (highly-resistant) to Class IV (nonresistant). Study showed that there were clear cut variations in natural decay resistance among different clones as well between the same clones. While G-48 clone from Pind Khakli, Hoshiarpur (Punjab) showed Class I (highly resistant) resistance, G-48 clone from Haryana Bungha, Hoshiarpur and Tajowal Mand, Kathgarh, Hoshiarpur were in Class IV (nonresistant). Similarly, G-3 clone from Brahman Majra, Jagadhri Tehsil, Yamunanagar (Haryana) showed Class II resistance against decay but G-3 from Haryana Bungha, Hoshiarpur and Pind Khakli, Hoshiarpu showed Class IV resistance (Table 1). Clone G-48 from Pind Khakli, Hoshiarpur and S7C15 from WIMCO, Rudrapur were found to be highly resistant 101 d. Heart rot in poplar a. Ganoderma lucidum e. Daldinia concentrica b. Phellinus pachyphloeus f. Pycnoporus sanguineus c. Fomes fomentarius g. Accelerated laboratory test for natural decay resistance in poplar wood Fig. 1. Fungal decay in poplar trees and wood, a.-d. decay fungi of tree, e.-f. wood decay fungi of storage and g. test for natural decay resistance in poplar wood. 102 ENVIS Table 1. Per cent weight loss in wood blocks of different clones of poplar S. no. Clone/ material 1. 2. 3. 4. S7C4 S7C15 G-48 WSL-39 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34. 35. 36. 37. 38. 39. Locality Sitapur, U.P. Bahraich, U.P. Mohali, Punjab W imco Seedlings, Rudrapur L-34 (TC) - do G-3 (Female) - do Uday - do WSL-42 - do S7C8 - do WSL A-26 - do G-48 - do S7C4 - do L-49 - do WIMCO-81 - do G-48 Pavan Poplar Ltd., Rudrapur S7C5 - do Uday - do S7C15 - do L Pandori Mindom ind, Punjab PD-124 - do G-48 - do G-3 Pind Khakli, Punjab G-48 - do G-48 Garhdewal, Punjab G-3 Hariana, Punjab G-3 Hariana Bungha, Punjab G-48 - do G-48 Bela Tajowal, Kathgarh, Hoshiyarpur G-48 Tajowal Mand, Kathgarh, Hoshiyarpur G-48 Santemajra, Hoshiyarpur G-48 Khadri Village, Jagadhri Tehsil, Yamunanagar G-48 - do G-48 Brahm an Majra, Jagadhri Tehsil, Yamunanagar G-3 - do G-48 Dakwala Village, Near Darpur, Yamunanagar G-48 Panjeto Village, near Chacharauli, Yamunanagar G-3 Aligarh, U.P. WIMCO-22 W IMCO Seedlings Ltd., Rudrapur, U.K. G-48 - do CD at 5% Forestry Bulletin, 12(1), 2012 Age (yrs) Percent weight loss (Resistance class) Sapwood (outer) Inner-wood (heartwood) W hite rot 39.09±1.89 (III) 29.41±3.29 (III) 31.22±4.80 (III) 16.99±3.08 (II) Brown rot 7.61±1.89 (I) 2.82±0.55 (I) 2.52±0.40 (I) 4.13±0.97 (I) W hite rot 23.69±1.69 (II) 32.03±2.99 (III) 25.59±3.86 (III) 41.39±5.25 (III) Brown rot 8.29±0.67 (I) 1.75±0.52 (I) 2.44±0.15 (I) 2.82±0.19 (I) 19.57±1.31 (II) 22.84±2.99 (II) 12.17±0.30 (II) 21.46±1.40 (II) 45.16±1.59 (IV) 26.72±1.53 (III) 24.93±1.51 (II) 31.80±2.72 (III) 38.34±7.92 (III) 27.68±3.49 (III) 35.40±2.26 (III) 3.37±0.43 (I) 3.82±0.96 (I) 8.18±0.33 (I) 10.59±0.70 (II) 9.74±0.40 (I) 3.77±0.91 (I) 2.29±0.30 (I) 14.66±1.05 (II) 2.80±0.33 (I) 3.99±0.94 (I) 9.87±1.71 (I) 25.88±2.82 (III) 21.75±6.32 (II) 39.03±4.99 (III) 34.25±3.14 (III) NA 34.05±7.95 (III) 37.05±6.47 (III) 36.65±5.11 (III) 59.01±4.98 (IV) 43.33±4.80 (III) 22.71±14.95 (II) 3.33±0.27 (I) 3.26±0.36 (I) 10.47±0.52 (I) 9.82±0.39 (I) NA 6.13±2.61 (I) 3.44±0.46 (I) 1.99±0.70 (I) 2.67±0.24 (I) 3.66±0.95 (I) 2.49±3.15 (I) 16 27.70±3.36 (III) 19.39±2.40 (II) 7.36±0.33 (I) 41.63± 3.80(III) 10.02±2.07 (I) 7.16±1.67 (I) 3.32±0.88 (I) 4.01±1.29 (I) 18.80±2.90 (II) 27.55±2.90 (III) 24.62±2.20 (II) 41.86±3.56 (III) 13.40±2.42 (II) 14.80±1.10 (II) 7.71±0.90 (I) 3.58±0.45 (I) 16 16 5-6 5-6 5-6 5-6 5-6 44.12±1.95 (IV) 34.80±1.06 (III) 45.06±3.36 (IV) 5.35±0.14 (I) 27.97±2.20 (III) 31.84±2.21 (III) 48.28±6.74 (IV) 3.57±1.51 7.60±0.44 5.61±1.09 3.04±0.49 4.50±0.19 6.09±1.23 6.51±0.21 (I) (I) (I) (I) (I) (I) (I) 41.75±4.51 (III) 43.23±2.09 (III) 43.93±3.26 (III) 43.85±3.65 (III) 49.36±2.15 (IV) 23.14±3.18 (II) 44.74±3.14 (IV) 3.73±0.98 2.83±0.62 3.83±0.36 2.81±0.55 4.13±0.28 2.62±0.65 4.84±0.79 5-6 5-6 50.09±1.13 (IV) 42.69±4.10 (III) 4.82±1.09 (I) 3.44±0.79 (I) 38.97±2.12 (III) 39.75±4.69 (III) 3.17±0.43 (I) 2.55±1.01 (I) 5 45.66±1.18 (IV) 4.41±0.96 (I) 55.19±4.58 (IV) 3.30±0.70 (I) 7 36.74±1.89 (III) 2.92±0.77 (I) 41.43±3.77 (III) 3.74±2.29 7 25.66±2.92 (III) 5.50±0.98 (I) - 5.68±0.91 (I) 4.5 6 43.21±3.17 (III) 23.04±3.38 (II) 6.23±1.03 (I) 5.22±0.41 (I) 41.80±4.33 (III) 16.61±0.28 (II) 10.06±0.57 (I) 4.16±0.36 (I) 8 7 16.37±0.84 (II) 35.78±3.53 (III) 5.18±0.58 (I) 4.72±0.67 (I) 18.38±1.09 (II) 37.93±2.38 (III) 2.33±0.41 (I) 4.39±0.49 (I) 7 39.02±1.68 (III) 4.16±0.34 (I) 40.74±5.13 (III) 3.90±0.60 (I) 23.18±2.83 (II) 29.95±5.89 (III) 3.06±0.32 (I) 3.36±0.36 (I) 32.60±2.18 (III) 15.25±1.26 (II) 2.85±0.28 (I) 3.54±1.56 (I) 27.66±1.86 (III) 4.28 1.32±0.66 (I) 1.07 44.71±5.11 (III) 4.13 2.38±0.35 1.21 6-7 6-7 6-7 6-7 6-7 6-7 6-7 6-7 6-7 6-7 6-7 (I) (I) (I) (I) (I) (I) (I) 103 clones against decay. These materials can be used for making decay resistant plywood as well as for construction and furniture making. Decay resistance was found to vary within a tree from base to top, maximum resistance was observed at 2.5 m height, above and below, it decreased considerably (Table 2). Resistance was more at the base than at the top of the tree. This quality can be used for selecting logs one meter above and below 2.5 meter from the base for selecting material for manufacturing decay resistant plywood and panels. Clones/source material showing resistance against decay will have potential for other uses, such as furniture making, construction, panelling, and will fetch good price to the growers. Management interventions could help poplar culture in delaying the decay of the wood. The field observations recorded over the poplar growing region indicates that the slow growing poplar especially planted on forest land gets more decay than that actively growing on farm fields. The decay further appears to be accelerated with termite infected fields when some trees may be totally hollow from bottom to top, though they may show some foliage on the crown. Wood decay in storage accelerates when logs get alternate wetting and drying during rains which causes conducive environmental condition for fungus to multiply and infestation. Poplar has largely developed a mechanism of fresh wood usage where it on harvest and conversion, is quickly transported to the marketing/ processing sites and immediately used. The problem of wood decay in storage is more common in government harvest and supplies which take a lot of time in harvesting, storage in depots before the logs are auctioned and, finally, used. Table 2. Natural decay resistance pattern within a tree (clone G-3, WSL-22 and G-48) at different heights H eig h t P er cen t w eig h t lo ss S a p w o o d (o u ter) W h ite ro t B row n rot In n er-w o o d ( h ea rtw o o d ) W h ite ro t B r ow n ro t G -3 B ase 1 .2 5 m 2 .5 0 m 3 .7 5 m 5 .0 0 m 6 .2 5 m Top 3 8 .2 7 ± 4 .41 3 0 .2 6 ± 1 .08 2 3 .1 8 ± 2 .83 4 1 .3 1 ± 1 .61 4 2 .6 5 ± 5 .69 4 8 .7 4 ± 4 .09 4 9 .2 8 ± 1 .15 4 .60 ± 0 .9 6 6 .05 ± 0 .8 1 3 .06 ± 0 .3 2 1 2 .5 0 ± 1 .29 1 0 .8 5 ± 0 .35 1 1 .9 0 ± 0 .43 1 2 .7 7 ± 1 .03 5 1 .7 7 ± 5 .49 3 7 .4 6 ± 2 .64 3 2 .6 0 ± 2 .18 3 3 .8 7 ± 2 .65 NM NM NM 8 .2 7 ± 1 .0 6 6 .7 3 ± 0 .7 7 2 .8 5 ± 0 .2 8 7 .3 8 ± 0 .8 0 NM NM NM W S L -2 2 B ase 1 .2 5 m 2 .5 0 m 3 .7 5 m 5 .0 0 m 6 .2 5 m Top 1 6 .0 7 ± 2 .65 9 .4 6 ± 2 .7 0 3 .4 8 ± 0 .4 8 4 .4 9 ± 1 .1 1 2 9 .9 5 ± 5 .89 3 1 .0 6 ± 3 .59 3 1 .3 4 ± 1 .62 1 .78 ± 0 .4 4 2 .07 ± 0 .2 2 1 .02 ± 0 .2 8 2 .31 ± 0 .4 2 3 .36 ± 0 .3 6 4 .99 ± 0 .9 4 5 .18 ± 0 .3 6 4 5 .7 3 ± 2 .99 2 9 .7 9 ± 1 1 .0 0 3 .0 2 ± 1 .0 6 1 4 .0 5 ± 2 .08 1 5 .2 5 ± 1 .26 3 1 .9 3 ± 2 .27 NM 3 .1 4 ± 0 .8 1 3 .1 1 ± 0 .5 7 3 .3 1 ± 0 .7 4 2 .0 7 ± 0 .6 7 3 .5 4 ± 1 .5 6 5 .6 1 ± 0 .5 3 NM G -4 8 B ase 1 .2 5 m 2 .5 0 m 3 .7 5 m 5 .0 0 m 6 .2 5 m Top 3 3 .7 2 ± 4 .42 2 9 .1 1 ± 6 .89 2 8 .1 8 ± 1 .85 3 4 .7 5 ± 6 .77 3 5 .4 7 ± 2 .77 3 8 .1 7 ± 1 .85 3 9 .2 2 ± 1 .33 1 .31 ± 0 .2 9 1 .28 ± 0 .1 7 1 .19 ± 0 .4 1 1 .57 ± 0 .2 5 2 .77 ± 0 .1 9 4 .49 ± 0 .2 2 4 .75 ± 0 .1 7 4 1 .7 3 ± 5 .78 4 0 .9 6 ± 6 .46 4 2 .3 3 ± 3 .48 4 7 .0 9 ± 4 .12 NM NM NM 2 .4 7 ± 0 .1 7 3 .0 7 ± 0 .2 0 2 .3 8 ± 0 .3 5 2 .7 4 ± 0 .2 0 NM NM NM *Not measurable (heartwood). References Bakshi, B.K.; Puri, Y.N. and Singh, S. 1967. Natural decay resistance of Indian timbers. I. Introduction and methods. II. Decay resistance of sal and teak. Indian Forester, 93: 305-328. Harsh, N.S.K. 2008. Researches on natural decay resistance of juvenile timbers like poplars. Project Completion 104 Report submitted to Department of Science and Technology, Government of India. 25p. Harsh, N.S.K.; Chandra, S.; Kumar, V. and Dhiman, R.C. 2009. Natural decay resistance of poplar wood in north India. In: National Forestry Conference, 4 th, Dehradun, 9-11November 2009. Abstracts. p. 148. Singh, P. and Singh, S. 1986. Insect pests and diseases of poplars. Dehradun, Forest Research Institute. p.74. z ENVIS Status of Insect Pests of Poplar in India with Special Reference to Clostera spp. Mukhtar Ahmad and Mohammad Faisal Forest Entomology Division, Forest Research Institute, Dehradun – 248 006 Introduction M As many as 133 insect species so far have been recorded by different workers at various locations infesting different poplar species in India Forestry Bulletin, 12(1), 2012 ost of the exotic poplars, especially Populus deltoides have been suffering multiple insect injuries since their introduction in India. Infestation by different insect species to poplar has been reported from time to time by many workers, including Pruthi and Batra (1960); Chatterjee and Thapa (1964); Seth (1969); Lohani (1976); Chatterjee and Chaturvedi (1981); Singh et al. (1983); Singh and Prasad (1985); Singh and Singh (1986); Sohi (1989), etc. Such reports provide specific information of insect incidences. Large scale defoliation of P. deltoides trial plantations (Clones G-3 and G-48, IC-100, 3-4 yrs of age) by Clostera cupreta (Butler) and C. fulgurita (Walker) was reported from time to time from the Central Tarai region of Uttar Pradesh (Seth, 1969; Lohani, 1976; Chaturvedi, 1981; Singh et al., 1983) . By 1980s, the defoliation outbreak spread over an area of 1,100 ha and became alarming. It had to be supressed by aerial spraying of carbaryl (Sevin) insecticide (Singh et al., 1983; Singh, 1998). This defoliator has now spread through out the region of P. deltoides growing. Large scale defoliation by Clostera spp. is known to significantly decrease the growth increment of poplar trees (Gao et al., 1985). Severe and repeated defoliation in young plants results in mortality (Singh and Singh, 1986). Severe attack by Apriona cinerea Chevrolat (poplar stem borer) was reported in 2-3 yrs old P. deltoides plantations, from Paonta Valley in Himachal Pradesh (Verma and Khurana, 1985); Jammu region (Sharma and Bhatia, 1996) and also from other parts of Uttar Pradesh and Haryana (Singh et al., 1987). Attack by this borer into the tree bole renders its timber unsuitable for any commercial use, as the entry of fungus and pathogens in the bored galleries also causes discolouration of its wood. It becomes weak, offering little resistance to wind and gets broken by a modest gust. Repeated attacks result in forking of the bole or mortality of tree (Singh and Prasad, 1985). In view of involvement of large number of insect species in different incidences on poplar trees, there was a need to have complete information of various insect species involved in causing multiple injuries to poplars. Few attempts were made in the past to glean information on poplar insects. Mathur and Singh (1960) were the first to list 42 insect species mostly indigenous to India and adjacent countries that caused damage to poplar and its timber in India. Later, Singh and 105 Singh (1975) listed 17 species as important pests of poplars. Sen-Sarma and Gupta (1979) have reported 33 poplar pests and highlighted the importance of Apriona cinerea Chevrolat, C. cupreta and C. fulguritia in causing major problems. Rishi (1979) identified 32 insect pests from Kashmir Valley pointing out that Lymantria obfuscate (Indian gypsy moth) and Aeolesthes sarta (Quetta borer – a xylophagous insect) as serious pests of hill poplars. Verma et al. (1983) reported 55 insects feeding on poplars in Himachal Pradesh along with information on their nature, extent of damage and control measures. Verma et al. (1983) considered 16 species as major or minor pests in various parts of India based on earlier reports Rawat, 1979; Rishi, 1979; Sen-Sarma and Gupta,1979; Singh and Singh,1986, identified 16 insects as important poplar pests from economic point of view in nurseries, plantation and natural stands. From Punjab, Sohi and Mann (1986) reported a species of leaf hopper, Kusala salicis (Cicadelidae) as a new pest of poplars. Sohi et al. (1987) had also identified poplar hairy caterpillar, Clostera restitura as a major defoliator of poplar in Punjab. Later, Sohi (1989) had listed 26 insects feeding on poplars from northwestern India. Singh (1991) had reported a polyphagous defoliator, Orgyia postica as new species defoliating P. deltoides in Uttarakhand. Recently, Ahmad and Faisal (2004) have reported caterpilars of Eupterote undata (Blanchard) causing defoliation to P. deltoides in nursery and plantation in parts of Uttarakhand. Most of such reports are based on limited information involving incidences of attack on poplar of particular location or region or state. In the present report a systematic account of infestation of all insect species on different poplar species reported so far in India is presented. Insect Pest Spectrum on Poplar As many as 133 insect species so far have been recorded by different workers at various locations infesting different poplar species in India. Although indigenous poplars are relatively safe from insect attack, exotic species have become soft target for insect infestation. These insects are represented by 42 families belonging to nine orders (Table 1). It includes all categories of pests including stem and shoot borers, defoliators, sap suckers, pests of felled trees and converted timber and termites, etc. Various insect species infesting poplars are systematically arranged order wise to which they belong with the record of infestation on different poplar species. Information is updated with recent findings so as to make a ready reckoner for the use of researchers and field workers. 106 Coleoptera Coleoptera forms a potential group of poplar pests as 36 insect species belonging to 8 families including Anthribidae, Buprestidae, Cerambycidae Chrysomelidae, Curculionidae, Lyctidae, Platypodidae and Scarabaeidae, etc. are reported to cause multiple injuries to different poplar species. Most of the species are borers but some are defoliators and also nursery pests. Anthribidae Family Anthribidae is represented by Tropiderinus muneeri (Bedel) whose larvae bore into the dead wood of P. euphratica (Beeson, 1941) causing infestation of moderate intensity. Buprestidae There are five buprestid borers recorded infesting poplar especially P. euphratica. Among these Capnodis kashmirensis Fairmaire and Chrysobothris femorata Oliv. are capable of causing considerable injury. Larvae mostly attack poplar which are damaged by wind, sun scaled or by breakage of branches. Larvae cause maximum infestation between the bark and wood, cutting off the flow of sap which results in girdling of the tree (Rishi, 1981). Capnodis miliaris klug was first recorded by Mathur and Singh (1960) on P. euphratica. It has also been observed infesting P. alba and P. nigra (Browne, 1968). It is a large black beetle 30 to 40 mm long with a covering of white, powdery deposit. Mathur and Singh (1960) reported infestation on dead wood of poplar by the larvae of unidentified species of Chrysobothris sp. Another buprestid beetle Melanophila picta indica infests dead wood of P. euphratica especially in the month of June (Beeson, 1941). Cerambycidae Eleven insect species belonging to family Cerambycidae have so far been found infesting on different species of poplar. While two species are defoliators, remaining nine cause infestation into growing shoots. Aeolesthes sarta Solsky: It is popularly known as ‘Quetta borer’ is a serious pest. Larvae feed on bark and sapwood and bore in to the stem and branches and make deep tunnels leaving packed dust. Its attack was first recorded by Mathur and Singh (1960) on P. alba, P. euphratica and P. nigra. Attack by this borer recurs for several years in successions, often killing the host by girdling (Browne, 1968). Heavily infested trees dry up in 3-4 yrs. Grub is difficult to control. Poisoning of tunnel gives protection only upto 40 per cent as the tunnel are kept packed with wood dust. Trees weakened either by defoliators’ attack or by repeated lopping of ENVIS Table 1. Insect pests of poplar infesting different parts of the tree Order Coleoptera Diptera Heteroptera Homoptera Family Anthribidae Species 1. Tropiderinus muneeri Status Borer of Dead wood Buprestidae 2. Capnodis kashmirensis 3. Chrysobothris femorata 4. Chrysobothris sp. 5. Capnodis miliaris 6. Melanophila picta indica Wood borer Wood borer Dead wood borer Wood borer Dead wood borer Cerambycidae 7. Aeolesthes sarta 8. Apriona cineria 9. Batocera rubus 10. B. rufomaculata 11. Glenea maculata 12. G. spilota 13. Purpuricenus indus 14. P. wachanrui 15. Saperda calcerata 16. Stromatium barbatum 17. Macrotoma crenata Bark and Sap wood borer Stem and root borer Stem borer Wood borer Defoliator Defoliator Dead wood borer Wood borer Wood borer Wood borer Stem borer Chrysomelidae 18. Crysomela populi 19. Plagiodera versicolora 20. Phyllodecta abdominalis 21. Nodostoma watehousei Defoliator Defoliator Defoliator Defoliator Curculionidae 22. Myllocerus cardoni 23. M. Pastulatus 24. M. discolor 25. M. discolor uniformis Defoliator Defoliator Defoliator Defoliator Lyctiidae 26. Lyctus africanus Sap wood borer Platypodidae 27. Crossatarsus wilmot Sap wood borer Scarabaeidae 28. Cotinus nitida 29. Hilyotugus holosericeus 30. Melolontha melolontha 31. Oryctus nasicornis 32. Protaetia impavida 33. Oxycetonia versicolor 34. Granida albosparsa 35. Holotrichia longispennis 36. Melolontha furicauda 37. Phtomyza sp. 38. Chrysocoris purpurpeus 39. Agnoscelis nubila 40. Kusala salicis 41. Aphis populi 42. Chaitophorus populi 43. C. kapuri Defoliator Defoliator Defoliator Defoliator Defoliator Defoliator Defoliator Defoliator Defoliator Leap minor Sap sucker Sap sucker Sap sucker Defoliator Defoliator Defoliator 44. Doraphis populi 45. Pemphigus immunis 46. P. bursarius 47. P. imaicus 48. Epipemphigus imaicus 49. Thecobius sp. 50. Pterocomma sp. 51. Chaitophorus dorocola 52. C. indica 53. C. populeti 54. Eriosoma lanuginosum Forms black galls Forms twig galls Forms twig galls Forms leaf galls Forms twig galls Defoliator Defoliator Defoliator Defoliator Defoliator Defoliator Agromizidae Scutelleriadae Pentatomidae Cicadellidae Aphidae Coccidae Contd. on next page… Forestry Bulletin, 12(1), 2012 107 ... Contd. from previous page 55. Pemphigus kashmiricus 56. P. mordwilkoi 57. P. nainitalensis 58. P. napaeus 59. P. spirothecae 60. Doraphis populi 61. Pterocomma populifoliae 62. P. populeum 63. Tuberolachnus salignus 64. Tuberolachnus sp. 65. Pseudococucus sp. 66. Pulvinaria vitis 67. Quadraspidiotus perniciosus Forms woody galls on twigs and branches Forms woody galls on twigs and branches Forms woody galls on twigs and branches Forms globose unilocular galls on the twigs Sap feeder, forms red, yellow or green spiral gall Infests arial portion of host Forms black galls Margarodidae 68. Drosicha stebbingi 69. Perisopneumon tamarinda Sap sucker Psyllidae 70. Megatrioza hirsuta 71. Pauracephala speciosa Sap sucker Forms open pit galls on leafs Sap sucker Sap sucker Sap sucker on stem, branches and twigs 72. Phylloplecta sp. 73. Phylloplecta gardeneri 74. Trioza gardneri Forms flattened, unicellular galls on leafs Sap sucker on leaf causing galls 75. Phyllocnistis populella 76. Tetraneara sp. 77. Pterocomma populeum 78. P. populifoliae 79. Messa populifiella 80. Xylocopa sp. Leaf miner Leaf miner Borer of felled trees 81. Coptotermes heimi 82 .C. kishori 83. Heterotermes indicola 84. Odontotermes distans 85. O. obesus 86. Microtermes unicolor 87. Phalanta (Atella) phalanta Defoliator Cossidae 88. Zeuzera coffeae 89. Z. oescelli Stem borer Stem borer Eupterotidae 90. Eupterote undata Defoliator Gelechiidae 91. Stenolechia sp. Skeletoniser and defoliator Geometridae 92. Ascotis selenaria 93. A. infixaria 94. A. selena ria reciprocaria Defoliator Defoliator Defoliator Lasiocampidae 95. Malacosoma indica 96. M. kashmirica Defoliator Defoliator Limacodidae 97. Cheromettia apicata 98. Thosea cana Defoliator Defoliator Lymantriidae 99. Lymantria dispar 100. L. obfuscata 101. Dasychira dalbergiae 102. Euproctis signata 103. Orgyia postica Defoliator Defoliator Defoliator Defoliator Defoliator Hymenoptera Tenthredinidae Xylocopidae Isoptera Rhinotermitidae Termitidae Lepidoptera Nymphalidae Contd. on next page… 108 ENVIS ... Contd. from previous page Orthoptera Thysanoptera Metarbelidae 104. Indarbela quardinotata Defoliator Noctuidae 105. Agrotis sp. 106. Helicoverpa armigera 107. Nycteola reuayana 108. Spodoptera litura Defoliator Defoliator Defoliator Defoliator Notodontidae 109. Clostera cupreata 110. C. fulgurita 111. C. retitura 112. Pygaera restitura 113. Neocerura liturata Defoliator Defoliator Defoliator Defoliator Defoliator Psychidae 114.Cryptothelia crameri Defoliator Pyralidae 115. Pyralis pictalis 116. Pyrausta dinasalis 117. Sylepta sp. Defoliator Defoliator Defoliator Sesiidae 118. Aegeria ommatiaeformis 119. Paranthrene tabaniformis 120. P. tabaniformis var. rhingaeformis Wood borer Wood borer Wood borer Sphingidae 121. Clanidopsis exusta 122. Hyloisus luscitiosa 123. Laothoe (Amorpha) populi 124. Smerinthus ocellatus 125. Pachysphinx modesta Defoliator Defoliator Defoliator Defoliator Defoliator Tortricidae 126. Eucosma glaciata 127. E. xerophloea 128. Gypsonoma hapalosarca 129. G. riparia 130. Gypsonoma sp. Shoot borer Defoliator Defoliator Defoliator Shoot borer Arctiidae 131. Diacrisia indica Acrididae Thirpidae 132. Schistocera gregaria 133. Scirtothrips dorsalis branches by local people fall an easy prey to this pest (Bhatt and Qadri, 1981) while, healthy trees have been found free from the attack by this pest (Stebbing, 1914). Dark brown or black beetle measures 2.5 to 4 cm in length while full grown larva measures up to 7.5 cm (Bhatt and Qadri, 1981). Apriona cineria: The stem and root borer is the most common and important species amongst xylophagous insects of poplar specially in north-west India. It attacks wide range of poplar clones and hybrids including Populus ‘Casale’, P. ‘Robusta’, P. nigra, P. x-euramericana, P. ‘regenerata’ and P. yunnanensis (Sen-Sarma and Gupta, 1979). Beetles feed on bark and young shoots while young larva after hatching enters the central pith region of stem and starts tunneling downwards, periodically ejecting the frass outside which is accumulated at the base of the stem. Larva continues tunneling from the stem in to the root and finally adult Forestry Bulletin, 12(1), 2012 Defoliator Sap sucker emerges from a circular hole above the ground level. Life cycle is completed in two years (Chatterjee and Sen-Sarma, 1968). Young plants up to the age of 3 years are more susceptible for its attack while large trees are almost free from Apriona attack. Up to 5 per cent young trees were reported severely attacked by this beetle in poplar plantations in sub montane track in Punjab (Sohi, 1990). Attacked trees become weak and are prone to breaking off by wind. Beetle has collateral host plants which include apple, mulberry, fig and willow (Chatterjee et al., 1969). Batocera rubus Linnaeus: It is commonly known as mango stem borer. It is a polyphagous pest infesting mango, jack fruit, rubber and fig trees. Larvae of B. rubus have been reported causing considerable damage to P. x-euramericana (Choudhary et al., 1970). Female lays eggs under the loose or wounded bark of stem or branches. Newly hatched grub 109 with its strong mandibles immediately starts boring into sapwood. Later the developing grubs make galleries in the stem as well as in thinner branches. Beetle emerge through the wide flattened holes in the bark (Choudhary et al., 1970). Although wood dust and excrement are ejected out from the entrance hole, symptoms of the attack are not always very clear. Attacked trees start shedding of the leaves and suddenly collapse due to severe hollowing. Batocera rufomaculata De Geer: It is a polyphagous pest widely distributed in the Oriental and Madagascar region, the Near East and in Caribbean islands. In Indian subcontinent it has been reported from wide range of dicotyledonous host trees including Acacia spp., Adina cordifolia, Albizia lebbek, Artocarpus hirsuta, A. integra, Bombax malabaricum, Dalbergia sissoo, Ficus spp., Morus alba, Shorea robusta, etc. Its infestation to P. x- euramericana was documented in a review on poplar insects (Thakur, 1999). Glenea maculata and G. spilota: These are two cerambycid defoliators of poplars. While G. maculata defoliates new flush of poplars in March, G. spilota feeds on the foliage of Populus ‘casale’, P. deltoides, P. nigra and P. ‘Robusta’ (Sen-Sarma and Gupta, 1979). Purpuricenus indus Semenov: It is a pest of dead wood. Larvae are reported to bore into heartwood of P. ciliata (Mathur and Singh, 1960). Another species Purpuricenus wachanrui Levrat (syn. P. haussknechti Witte) is reported to breed in P. ciliata in Pakistan and is considered to be an important pest. The long horn borer is also distributed in the Near East including Cyprus and eastward to India (Browne, 1968). Saperda calcerata (Col.: Cerambycidae) is reported to infest old trees of P. deltoides in certain areas of Kashmir Valley (Rishi, 1981). Sapoozing and frass at the base of the tree are indications of the attack. sometimes to trunk, making zigzag tunnels, which are packed with compact mass of fibres and excreta. Emergences of adults take place in July. Chrysomelidae There are four species of chrysomelid beetles reported infesting various species of poplar. All the four species are defoliators. Chrysomela populi: It is one of the major defoliator of poplar and Salix in the valley of Kashmir. Its infestation on P. ciliata was first reported in India by Beeson (1919). The beetle is prevalent in the forest nurseries in Kashmir where it attacks Populus ‘Casale’, P. deltoides, P. ciliata, P. nigra ‘Italica’, P. ‘Robusta’, P. Reinebeck’, P. ‘Regenerta’ and P. alba (Ahmad and Ashraf, 1981). It defoliates P. yunnanensis in Kumaon region. Severe defoliation causes die-back in shoots and serious loss in increment. Plagiodera versicolora: It is commonly called as willow leaf beetle infests foliage of poplars and willows from April to June. A brilliant, bluish green beetle spends winter in adult stage under the bark or in debris near the base of trees. The beetles swarm on the trees in April or May and feed for a short period, skeletonizing the leaves. Female lays irregular masses of eggs on leaves, which hatch in about a week. Larvae feed gregariously on both the surfaces of the leaf. There are at least two generations in a year. Heavily infested trees become entirely brown by September end (Singh and Singh, 1986). Phyllodecta abdominalis Baly is reported to cause defoliation to P. ciliata and P. nigra (Sen-Sarma and Gupta, 1979). Defoliation to P. ciliata, P. casale, P. deltoides, P. nigra and P. ‘Robusta’ by Nodostoma watehousei was reported by Mathur and Singh (1960). Stromatium barbatum Fab.: It is a polyphagous pest of timber especially in furniture, wood work in houses, packing cases, doors and windows, etc. About 350 different kinds of wood are attacked by this species (Beeson and Bhatia, 1939). Its infestation to the wood of P. ciliata and P. tremula has been reported by Mathur and Singh (1960). In majority of cases, its damage is manifested after a long time of its infestation due to long larval life. Curculionidae Four curculionid weevils have so far been reported to cause infestation to poplars by way of defoliation. Myllocerus cardoni and M. pastulatus were observed feeding on the foliage of various clones of P. deltoides with light to moderate intensity in poplar nurseries in Mala and Campiergang, (U.P.) (Thakur, 1981). Myllocerus discolor Boheman, a polyphagous defoliator was reported feeding on poplar leaves by Beeson (1941). Defoliation by its sub species M. discolor uniformis Marshall, was reported by Mathur and Singh (1960). Macrotoma crenata: It is a polyphagous species infesting Populus spp. in India upto 2,000 m in the Himalaya (Singh and Singh, 1986). The beetle is dark brown measuring 28 to 58 mm in length and has rough pitted surface. The grubs bore into the stem and Lyctiidae and platypodidae Lyctus africanus Lense, and Crossatarsus Wilmot are the only members of Lyctiidae and Platypodidae, respectively infesting poplars. Beetle and larvae of L. africanus bore in the sapwood and (Table 1) damage wood of P. euphratica 110 ENVIS while adults and larvae make small numerous tunnels into the wood of P. ciliata (Mathur and Singh, 1960). summer. Affected plants show light defoliation and stunting growth of shoots. Scarabaeidae Scarabaeidae beetles are polyphagous and form a strong group of nursery pests. While adult beetles defoliate the plants, the larvae which are commonly called chafer grubs, live inside the soil and feed on the roots and its bark. So far, nine species of scarabaeid beetles have been reported infesting different species of poplar in the nurseries. Cotinus nitida, Hilyotrugus holosericeus Redtenbacher, Melolontha melolontha L., Oryctus nasicornis Linnaeus and Protaetia impavida have been reported infesting poplar nurseries in Kashmir Valley (Rishi, 1981). Oxycetonia versicolor Fab. has been reported by Mathur and Singh (1960) as the pest of poplar nurseries. Remaining three species including Granida albosparsa Moser, Holotrichia longipennis Blanchard and Melolontha furicauda Ancey have been reported as the pest of poplar nurseries by Singh and Singh (1986). The chaffer grubs of late have also been recorded attacking young nursery plants during March-April and damage of around 10 per cent plants have been recorded in some nurseries in Uttar Pradesh and Uttarakahnd. Homoptera Diptera Agromizidae The order Diptera is represented by only one species of leaf miner, Phytomyza sp. larvae mines into the upper surface of the leaf. Its infestation was first recorded on different clones of poplar in Dhubri and Calcutta (Vijay Veer and Chandra, 1984). Infestation results in deformation, curling and premature leaf fall. Heteroptera Order Heteroptera is represented by its three members including Chrysocoris purpurpeus Westwood (Scutelleridae), Agnoscelis nubila Fabr. (Pentatomidae) and Kusala salicis (Ahmed) (Cicadellidae) (Sohi and Mann, 1986; Tewari, 1993; Roychoudhury et al., 1994). Chrycosocoris purpurpeus: It is a sap sucking bug which has been recorded infesting poplar in a nursery at Jabalpur (M.P.) Agonoscelis nubila is widely distributed in many countries including China, Japan, Myanmar, Sri Lanka, etc. Its infestation to poplar has been reported in Karnataka, Kashmir, Arunachal Pradesh, Maharashtra, Tamil Nadu and West Bengal (Tewari, 1993). It passes five generations in a year. Insects suck the sap from foliage and green tender shoots which is harmful especially during dry period in Forestry Bulletin, 12(1), 2012 About 40 homopteran species so far have been recorded infesting on different poplar plants. Majority of them are aphids while others include membracids, coccids and margarodids. Aphis populi (Aphidae): Aphis populi along with Chaitophorus populi was recorded infesting P. alba in nurseries and plantation in Kashmir (Rishi, 1981) although A. populi was first reported on P. alba by Mathur and Singh (1960). Other aphid species C. kapuri and Tetraneara spp. were reported infesting the stem of P. ciliata in Kashmir (Rishi, 1981) while Maity and Chakrabarti (1981) reported C. kapuri infesting in cluster on lower and upper surface of poplar leaves in Shimla (H.P.). This species is known from north-west Himalayas. Cocccid type aphid Doraphis populi forms coccid black galls on P. aurea (Rishi, 1981). At high elevations Pemphigus immunis Buckton, P. bursarius Linnaeus and Epipemphigus imaicus Cholodovsky were reported forming twig galls on P. nigra var. Italica, P. ciliata and P. caspica (Rishi, 1981). Formation of leaf gall by Pemphigus imaicus Buckton on Populus ciliata and on P. tremula, P. nigra, P. ‘Italica’ and P. caspica by Pemphigus immunis was first reported by Mani (1955) and Mathur and Singh (1960). Infestation of Thecobius sp. and Pterocomma sp. have also been recorded on poplar at high elevations of Kashmir (Rishi, 1981). Chaitophorus dorocola Matsumura was collected from north-east India on poplar (Maity and Chakrabarti, 1981). This species is known to infest P. maximowiezii and P. sieboldi in Japan (Higuchi, 1972). Chaitophorus indica Ghosh has been reported from northeast Himalaya (Maity and Chakrabarti, 1981). It is found in cluster on the undersurface of both young and mature leaves. It has been collected from Darjeeling, Kalimpong, Tashing Durbin and Kamsi (West Bengal) (Chakrabarti, 1977). Chaitophorus populeti (Panzer) (syn. Aphis populeti) is reported to infest P. alba in Kashmir (Maity and Chakrabarti, 1981). Eriosoma (Schizoneura) lanuginosum (Hartig) (syn. Eriosoma taskhiri): This is another aphid reported to infest poplar in Kashmir (Maity and Chakrabarti, 1981). It is distributed in India (Kashmir), Pakistan and Afghanistan (Mani, 1973). Pemphigus kashmiricus Rishi: It was reported infesting poplar in Kashmir (Rishi, 1979). Pemphigus mordwilkoi Cholodovsky and P. nainitalensis Cholodovsky are common 111 aphids in Himalayan zone, where they form woody galls on the twigs and branches of P. ciliata (Beeson, 1941; Mani, 1955). Pemphigus napaeus Buckton: This forms globose, unilocular galls on the twigs of P. ciliata and P. euphratica in Himalayas upto an altitude of 3,000 m or more (Mani, 1955). Pemphigus spirothecae Passerini: It is a spiral gall aphid, widely distributed in northern India and also in Britain. It feeds on the sap of leaf petioles of P. nigra and P. nigra var. italica. Its feeding causes the formation of red, yellow or green spiral gall on the infected petiole during the summer months. Infestation of this aphid on P. nigra was first recorded by Mathur and Singh (1960). Infestation by Doraphis populi (Maskell) to poplar was reported by David et al. (1971), (Rishi, 1979) and Maity and Chakrabarti (1981). Pterocomma populifoliae (Fitch) has been reported to infest Populus sp. in north-east India and also from north-west (Maity and Chakrabarti, 1981). Richards (1967) reported that the species usually infest the aerial portions of its hosts. Pterocomma populeum (Kaltenbach) was reported from Kumaon Himalaya (van der Goot, 1916). Tuberolachnus salignus Gmelin (syns: Cinara saligna, Pteroclorus salignus, Tuberolachnus viminalis): It is commonly called as gaint willow aphid; widely distributed in temperate regions of Africa, America, Asia and Europe. A large brown aphid, easily recognized by the presence of a prominent, dark mid-dorsal abdominal tubercle and by a rich pink stain, which is yielded when crushed. It occurs in large colonies, feeding on the sap of stems, branches and twigs. It has been recorded infesting on P. maximowiezii and P. nigra and some species of Salix. Vijay Veer and Chandra (1984) recorded another species of Tuberolachnus infesting on some clones P. deltoides in Dhubri (Assam). Aphids were found sucking the sap from tender shoots of saplings and plants, which results in die-back of twigs. Aphids infested twigs or shoots become black due to the growth of fungus on honeydew of aphids. Pseudococcus spp. (Coccidae): This was reported sucking the sap of foliage and branches of P. euphratica (Mathur and Singh, 1960). Another coccid Pulvinaria vitis (L.) was recorded to infest P. ciliata (Sharma and Sharma, 1993) Quadraspidiotus perniciosus Comstock is one of the most important polyphagous pests widely distributed throughout India especially in Kashmir infesting poplars and other fruit trees (Singh, 1963; Browne, 1968; Rishi, 1981). Shoots, stem and twigs of young trees are attacked resulting in withering and death of the tree. Its host range encompass about 2,000 hosts plant (Rishi, 1977). Drosicha stebbingi Green 112 (Homoptera : Margarodidae) a large scale insect, which is principally a pest of Magnifera indica and Shorea robusta, but also infests numerous other dicotyledons and occasionally conifers. Its infestation to poplar has been noticed in nurseries (Tewari, 1993). Perisopneumon tamarinda Green (Margarodidae) (syn: Drosichiella tamarinda): It is a polyphagous mealy bug which feeds on the sap of various dicotyledonous trees including Populus sp. Female lays eggs in silken egg-sacs in September, at a depth of about 5 to 15 cm in soil, and hatch following April only. Young nymphs climb on to the host plant to feed. Life cycle is annual (Browne, 1968). Megatrioza hirsuta (Crawford) (Homoptera: Psyllidae): It is a jumping plant louse which is widely distributed in India. It feeds on the sap of Terminalia tomentosa causing distortion to the leaves (Browne, 1968). Tewari (1993) has reported its infestation to poplar. There are two generations in a year. Females of one generation lay eggs in the bark cavities in November which over winter. They hatch in April and nymphs move to young leaves where they feed gregariously and complete the development in June. The adults lay eggs on shoots and leaves and nymphs of this generation feed on the sap of the foliage, becoming adults in November. Feeding causes leaf margins to roll upwards and inwards until they meet at the mid rib and the rolled part become swollen. Incidence of attack on young plants is relatively higher. Pauracephala speciosa (Homoptera: Psyllidae): It is reported to attack P. ciliata in Shimla (H.P.). It forms open pit galls on the leaves which results in curling in case of heavy infestation (Kaul and Sharma, 1982). Phylloplecta gardeneri (Laing) (Homoptera: Psyllidae): It makes flattened, unicellular galls on the leaves of P. euphratica, which are usually separate, yellowish to dark green , smooth and about 5x4 mm in size. A leaf may carry up to 18 galls on both the surfaces. The adults appear with the advent of new foliage in January-February and gall formation starts immediately. One nymph inhabits each gall. Last moulting takes place inside the gall (Beeson, 1941). Another species of Phylloplecta makes large globular galls on the twigs of P. euphratica, which vary in size up to 12 mm and are formed on the youngest shoot and remain for several years (Beeson, 1941). Trioza gardneri Laing is a jumping plant louse which occurs as the minor pest of P. euphratica. The adults get active early in the year when new foliage is unfolding (Browne, 1968). Nymphs feed on the sap of leaf causing formation of galls. Family Lithocolletidae is represented by only one insect, Phyllocnistis populella ENVIS Chambers. It mines the under surface of the poplar leaves causing browning (Rishi, 1981). Hymenoptera The order is represented by only two insects. Messa populifiella (Tenthredinidae) mine the under surface of poplar leaves causing browning and finally drying while Xylocopa sp.(Xylocopidae) bore into the felled trees of poplar (Rishi, 1981). Isoptera Six species of termites, five belonging to family Rhinotermitidae and one to family Termitidae represent Isoptera. Coptotermes heimi (Rhinotermitidae): It is one of the most serious pest, largely responsible for die-back and mortality in some clones of P. deltoides, especially 65/27 which was ultimately discarded for planting in Tarai region of Uttar Pradesh (Thakur, 1981). Other rhinotermitid species implicated with the damage in poplars include Heterotermes indicola, Odontotermes distans and O. obesus (Thakur, 1981). Termites gain entry either through the roots or injured portion of the stem near the ground level. After gaining entry, they start infesting upward and radially in the main bole resulting in hollowing of the tree. Another rhinotermitid, Coptotermes kishori Roonwal and Chhotani was recorded infesting poplars in Assam (Berivara) (Vijay Veer and Chandra, 1984). Main root of over 10 per cent plants was found damaged by this species. Microtermes unicolor Snyder (Termitidae): It was observed to cause extensive damage to IC clone of P. deltoides plantation at Bahalpur (Assam) (Vijay Veer and Chandra, 1984). Lepidoptera Lepidopterans make an important group of poplar pests. So far 45 lepidopteran insect species have been recorded infesting different species of poplars. Most of them are defoliators, while some are borers, sapsuckers, skeletonisers and nursery pests. Nymphalidae Phalanta (Atella) phalanta: It is the common butterfly occurring in fast growing species of poplar especially in Tarai region of Uttarakhand although its infestation was first reported by Rawat (1981). Larvae feed on poplar leaves along with other defoliators. Cossidae Family Cossidae is represented by two species including Zeuzera coffeae Nietner and Z. oescelli. Both the species are Forestry Bulletin, 12(1), 2012 borers of poplar trees. The larvae bore into the stem and branches of saplings. The portion of branches above the point of entrance gets dry. Eupterotidae Family Eupterotidae is represented by Eupterote undata. Larvae are reported infesting the foliage of P. deltoides in nursery and plantations (Ahmad and Faisal, 2004) Gelechiidae Family Gelechiidae is represented by Stenolechia sp. Young larvae are reported to skeletonise and later defoliate P. euphratica (Mathur and Singh, 1960). Geometridae Family Geometridae is represented by two species and one subspecies. Ascotis selenaria Deris and Seliff and A. infixaria were reported to cause defoliation to P. deltoides, P. ‘Casale’ and P. ‘Robusta’. Subspecies, A. selena ria reciprocaria Walker was also reported defoliating same species of poplar (Tewari, 1993). Lasiocampidae Two species of family Lasiocampidae were reported infesting some species of poplar. Malacosoma indica Walker defoliates P. ciliata in hilly areas of Uttarakhand and Himachal Pradesh (Singh and Singh, 1986). It is highly polyphagous. Besides poplar, larvae frequently attack Quercus dilatata, Q. leucotrichophora, Pyrus pashia, Prunus padam, apple, almond, apricot, cherry, gooseberry, peach, pear, walnut, etc. The caterpillars web a tent like nest at the forking of twigs and hide in the nest while resting. The young larvae- feed on expanding buds while advanced stage larvae congregate on the leaf lamina and feed voraciously. Another species of Malacosoma; i.e., M. kashmirica was recorded on poplars in the hilly region of Kashmir valley (Rishi, 1981). The larvae are voracious feeders on the foliage leaving behind only mid rib. Its damage on poplar was more pronounced in nursery. Main infestation period was April to June. Limacodidae Two defoliating species including Cheromettia apicata Moore and Thosea cana Walker attack poplars. Caterpillars of these two moths were reported defoliating Populus ‘Casale’, P. deltoides and P. ‘Robusta’ (Mathur and Singh, 1960). Lymantriidae Larvae of five species belonging to family Lymantriidae were reported to defoliate different species of poplar in India. Lymantria dispar Linnaeus (syn. Protheria dispar) is commonly known as Gypsy moth. The larvae are 113 polyphagous on the foliage of many broad-leaved plants and also to some extent to conifers. Larvae have been recorded causing defoliation to P. tremuloides and Salix spp. among other tree species (Browne, 1968). Larvae of Lymantria obfuscata Walker have been reported as defoliators of the poplar (Mathur and Singh, 1960). The clusters of larvae of this pest could be seen during daytime on the trunk of poplar during June-July in Kashmir (Rishi, 1981). Maximum consumption of the foliage by the larvae was observed during dawn and dusk. Dasychira dalbergiae was reported as an important defoliator of Populus ‘Casale’, P. deltoides, P. nigra, P. trichocarpa and P. ‘Robusta’ (SenSarma and Gupta, 1979). Euproctis signata, commonly called as brown tail moth, has been recorded on poplars as a minor pest in Kashmir Valley (Rishi, 1981) although it is primarily a pest of the fruit trees. Larvae feed on tender foliage and buds in May and , continue to skeletonize leaves until late summer. Caterpillars of another lymantriid, Orgyia postica were found defoliating poplar specially P. deltoides in poplar growing areas in Uttar Pradesh and Uttarakhand (Singh, 1991). defoliation in poplar has been regularly reported in Tarai region of Uttarakhand since 1966 (Seth, 1969), but involvement of C. cupreata in large scale infestation was first reported. It defoliates many species of poplars. P. deltoides is the most attacked species, which experiences epidemic defoliation almost every year in some locations. It defoliates P. ciliata in Jammu and Kashmir (Singh and Singh, 1986). Its attack starts in the month of March-April. The eggs are laid on the leaf surface in-groups of 200-300. It completes its life cycle within 19-20 days. There are 8-9 generations in a year in plains. Metarbelidae Two species belonging to family Metarbelidae were reported to infest poplar. These cause substantial damage to poplars. Indarbela quardinotata Walker, a polyphagous species, has been reported attacking branches and shoots of many clones of P. deltoides in Dhubri (Assam) and Calcutta (Vijay Veer and Chandra, 1984). Larvae get entry into the branches through snags. Attack reduces the plant vigour. Rawat (1981) reported defoliation to certain clones of P. deltoides by Inderbela spp. in Tarai region of Uttarakhand. C. (syn. Pygaera) restitura Walker: It was reported as the pest of S. babylonica (Mathur and Singh, 1960). It has also been reported as the pest of Populus sp. and Salix sp. in Pakistan (Browne, 1968). Mann (1981) had reported P. restitura as the pest of poplar in India. Another two notodontid species including Neocerura liturata Walker and N. wisei Swinhoe were reported to cause defoliation of P. ciliata. Noctuidae Family Noctuidae is represented by four species which are mostly defoliators, however, large scale damage by any noctuid has not so far been reported. Agrotis sp. has been reported as minor pest of poplar especially at nursery stage (Rishi, 1981). Mathur and Singh (1960) have reported defoliation of P. euphratica and P. ciliata by the larvae of Helicoverpa armigera and Nycteola reuayana Scopuli, respectively. Larvae of Spodoptera litura have also been reported defoliating poplar. Notodontidae Family Notodontidae is represented by five species. Some representatives are potential pests causing considerable damage to poplar. Clostera cupreata (syn. Pygaera cupreata) and C. fulgurita: These are the major defoliators of poplars. Although epidemic 114 C. fulgurita: It attacks several species of poplars including P. ciliata, P. deltoides, P. nigra and P. alba and some species of willows; i.e., S. alba, S. babylonica and S. tetrasperma. C. cupreata along with C. fulgurita have caused epidemic defoliation to poplar in Tarai region of Uttarakhand, several times since 1966 (Seth, 1969; Lohani, 1976; Singh et al., 1983). Moth starts laying eggs in the month of March - April on the under surface of the leaf. One female deposits 500-700 eggs. There are about 10-12 generations in a year in the plains of North India. Psychidae Only one species Cryptothelia crameri was reported to defoliate P. deltoides and P. ‘Robusta’ (Kaul and Sharma, 1982). Pyralidae Three species belonging to this family have been reported as defoliators of poplars. Pyralis pictalis Curtis was found defoliating P. alba (Mathur and Singh, 1960) while Pyrausta dinasalis Walk. defoliates P. ciliata and P. deltoides (Beeson, 1941; Vijay Veer and Chandra,1984). Another pyralid Sylepta sp. has been reported as the defoliator of P. deltoides and P. ‘Robusta’ (Kaul and Sharma, 1982). Sesiidae Family Sesiidae is represented by three species. All of them are borers to poplar. Aegeria ommatiaeformis Moore bores P. euphratica and some other species of poplar (Mathur and Singh, 1960). Paranthrene tabaniformis Rottenburg: It is a pest of some ENVIS poplar and Salix species. Recorded hosts include P. alba, P. deltoides, P. nigra and P. tremula (Browne, 1968). The adults emerge during mid summer. Eggs are laid singly in the cracks in bark of the tree. The larvae make tunnel in the bark and wood. Heavily infested trees are weakened and rendered liable to wind break. Subspecies, Paranthrene tabaniformis var. rhingaeformis Hubner has been reported as borer of P. alba (Mathur and Singh, 1960). the plants. Its infestation has been recorded on P. nigra (Mathur and Singh, 1960). Sphingidae It is represented by five insect species including Clanidopsis exusta Butler, Hyloisus luscitiosa Clemens, Laothoe (Amorpha) populi Linn; Smerinthus ocellatus Linn. and Pachysphinx modesta Harris. Larvae of these species were reported to defoliate poplar species (Mathur and Singh, 1960). Larvae of L. populi are solitary feeders, attain a length of about 6.5 cm and become yellowish green when fully grown. The adults usually have a wingspan of about 10 cm (Browne, 1968). Management of Poplar Defoliators, Clostera spp. Tortricidae Five insect species belonging to this family have been recorded infesting poplars. Eucosma glaciata Meyrick is commonly called as poplar shoot borer. Mathur and Singh (1960) first recorded its infestation to poplar. It is one of the destructive insects of young poplars particularly in nurseries. Larvae feeding on terminal tissues prevent normal growth and may kill the growing tip, which results in forking. Another species of Eucosma; i.e., E. xerophloea Meyrick was reported to be the pest of P. euphratica. Larvae skeletonise the foliage (Mathur and Singh, 1960). Defoliation of P. euphratica by Gypsonoma (=Eucosma) hapalosarca Meyrick in Punjab was reported by Beeson (1941). Larva of Gypsonoma riparia skeletonises and webs together the leaves of P. euphratica during July to September (Beeson, 1941). An unidentified species of Gypsonoma sp. was reported to make tunnel in shoots and branches of P. deltoides (Rishi, 1981). The larvae tunnel in the pith of terminal buds, stunting and distorting the growth and often kill them. Terminal growth is slowed and the trees become forked with heavy branching. Arctiidae Larvae of Diacrisia indica were reported to defoliate Populus ‘Casale’, P. deltoides and P. ‘Robusta’ (Sen-Sarma and Gupta, 1979). Orthoptera Nymphs and adult grass hoppers of Schistocera gregaria Forskal (Acrididae) feed on the foliage of lower portion of Forestry Bulletin, 12(1), 2012 Thysanoptera Scirtothrips dorsalis Hood (Thirpidae): It sucks sap resulting in curling and deformation of leaves. It is a minute, yellow colour thrip which attacks young leaves or half-open buds (Vijay Veer and Chandra, 1984). Although over 133 insect species of varying nature of damage have so far been recorded causing infestation to the poplar of different dimensions (Batra, 1960; Chatterji and Thapa, 1964; Singh and Prasad, 1985; Singh and Singh, 1986; Sohi and Mann, 1986; Pruthi and Sohi, 1989; Tewari, 1993). Poplar defoliators, C. cupreata and C. fulgurita are the two major pests which have often caused severe defoliation to the poplar in main planting areas of northern India (Seth, 1969; Lohani, 1976). Such defoliation in large areas on regular basis adversely affect the growth increment and also reduce the quality of the timber. On few occasions, epidemic defoliation by these insects was suppressed by aerial spraying of insecticides (Singh et al., 1983). Keeping in view the exorbitant expenditure involved in aerial spraying and the quantity of environmental dis-harmony caused by large scale application of chemical insecticides, it was mandatory to explore the avenues other than pesticides’ application for effective management of the primary defoliators, C. cupreata and C. fulgurita. Realizing the gravity of problem, many workers have attempted to evolve alternate environment friendly methods to contain the problem of defoliation. During present attempt, efforts are made to review all such trials to formulate an integrated approach to contain the problem of insect defoliation in poplar nurseries and plantation. Surveillance of the Pest Problem The importance of understanding the extent of insect activity in an area to make decisions in insect pest management cannot be overstated. Indeed, this knowledge is indispensable to the paramount principle of pest management: to take no action against a pest unless that pest is known to be present and posing an actual or potential threat. Such insect activities as forest invasion, long-range migration, local movement, feeding and reproduction are 115 detected and documented through pest surveillance. Pest surveillance is the watch, kept on a pest for the purpose of decision making. Depending on the kind of pest (native, newly introduced, potential invader), surveillance programmes attempt to estimate the numbers in a population and their distribution, and to assess how these factors change over time. More succinctly stated, the major objectives of surveillance are detection of species presence and determination of population density, dispersion, and dynamics. Besides institutes of ICFRE, forest departments, farmers raising poplar plantations, NGOs involved in research on poplars and other institutions/companies promoting poplar planting are the agencies conducting surveillance of such nature. An insect pest survey is a detailed collection of insect population information at a particular time in a given area. The survey programme may be carried out for an entire growing season or at certain critical period in the insect life cycle. Surveys may be classified as ‘qualitative’ or ‘quantitative’. Qualitative surveys are the least complex and are generally aimed at pest detection. Usually, qualitative surveys yield lists of pests species discovered, along with a subjective reference to density, for example, abundant, common, rare, etc. Quantitative surveys are the most common type employed in insect pest management. The quantitative survey attempts to define numerically the abundance of an insect population in time and space. Such information is used to predict future population trends and to assess potentialities of the pest population. To collect information in the quantitative survey, a count of insects or a measure of their presence is required. Because of the great number and/or secretive nature of many insects, it is not feasible or even desirable to take a census to count every individual in the population. Instead, it is usually more efficient to estimate population density by sampling. Success of any pest management programme is largely dependent upon proper and regular surveillance and monitoring the pest situation. It is necessary to monitor the pest problem and record the population trends of pest as well as its natural enemies. Changes in pest distribution and its abundance and the influence of biotic and abiotic factors on pest population would greatly help in adopting proper control strategy. Regular surveillance of the pest situation would further help to evaluate the pest and parasitoid composition in the field which in turn provides suitable data for forecasting the future level of pest population besides marking the appropriate time for field release, etc. 116 Utilisation of Relative Natural Insect Resistance in Poplar Host plant resistance refers to the heritable qualities of a cultivar to counteract the activities of insects so as to cause minimum per cent reduction in yield as compared to other cultivars of same species under similar conditions (Dhaliwal et al., 1993). Snelling (1941) defined plant resistance as those characters that enable a plant to avoid, tolerate or recover from attacks of insects under conditions that would cause greater injury to other plants of the same species. Resistance to insect is the inheritable property as perceived by Kogan (1982) that enables a plant to inhibit the growth of insect populations. ‘Relative insect resistance’ can be assessed by the following characters: 1. It is heritable and controlled by one or more major genes. 2. It is relative and can be measured by comparing with other cultivars of the same species. 3. It is measurable quantitatively as well as qualitatively. 4. It is variable and can be modified by abiotic and biotic factors. Ahmad (1993) had tested 109 clones of P. deltoides belonging to Europe, America, Australia, United Kingdom and Turkey for determining the presence of relative resistance to the primary defoliator of poplar, C. cupreata. Critical difference in mean leaf area of different clones consumed by the larvae was made the basis for evaluation. Resistant clones were grouped as ‘most resistant’ (R1) ‘resistant’ (R2), and ‘moderately resistant’ (R3), while susceptible clones as Sl, S2 and S3 on the basis of weightage percentage of resistance/ susceptibility. Clone 67 of USA/Alabama (33o N lat.) was found to be most resistant clone with weightage percentage of resistance as 100 followed by A 37 T 100 of FGR / Alabama (USA) and S1’92 of USA (Stoneville). 109 clones were placed into six homogenous groups of 13, 26, 19, 24, 14, and 13 in different categories as R1, R2, R3, Sl, S2 and S3, respectively. Clone 100 of USA (34oN lat.) was judged as most susceptible followed by 2498 of Netherlands/Illinois and S7C20 Stoneville, USA. Plant resistance has many advantages as a primary tactic in insect pest management strategies. Among all the important parameters or factors are effectiveness, selectivity against the pest, relatively long stability, compatibility with other tactics, and human and environmental safety. In addition, resistant varieties can be adopted into tree protection schemes easily and economically, resulting in both ENVIS short-term and long-term gains. Although, the gains of developing and using resistant plants far outweigh the disadvantages, the most important limitations of the approach include time required for development and problems with biotypes. Biotypes are sure to develop over a period of time. To avoid/cope with this, vertical resistance should be avoided and polygenic resistance must be encouraged. Regular testing is therefore necessary to introduce/replace the resistant variety with the latest highest resistant variety at an appropriate time. Resistance or susceptibility of plants to the insect is the result of a series of interactions between plants and insects which influence the ultimate degree of establishment of insect populations on plants (Saxena and Pathak, 1979; Saxena, 1986). The factors which determine insect establishment on plants can be categorised into two groups: (1) Insect responses to plants, and (2) Plant characters influencing insect responses. The insect responses include orientations, feeding, metabolic utilisation of ingested food, growth of larvae to adult stage, adult longevity, egg production, oviposition and hatching of eggs. Unfavourable biophysical or biochemical plant characters may interrupt one or more of these insect respnoses inhibiting establishment of an insect population on a plant and rendering it resistant to infestation and injury. This is a field which may be worked out separately for each plant species to ascertain the definite factors responsible for relative insect resistance. Use of Biopesticides/Antifeedants Much before the advent of synthetic organic insecticides various botanical pesticides including neem, bakain, pyrethrum, rotenone, nicotine, etc. were being used to suppress the pests of agriculture in different parts of the world. It is estimated that there are about 500,000 different plant species present globally. Most of these plants contain bioactive organic chemicals. However, only 10 per cent of these plants have so far been examined for their pesticidal property (Benner, 1993). Since the realization of remarkable insecticidal properties of plant species like Chrysanthemum sp. (Family: Compositae), a new era was opened and Pyrethrum was used extensively for the control of various insect pests in different parts of the world (Russell and Knipe, 1941; Senior White, 1945; Muirhead-Thomson, 1948). Other prominent plant species and their products which were in use include Tephrosia sp. (Barnes and Freyre, 1966), Derris sp., Nicotiana sp., Citronella oil, Eucalyptus oil, etc. (Curtis, 1990). Forestry Bulletin, 12(1), 2012 Insecticidal properties of root and bark extracts of Dalbergia stipulacea in acetone and in alcohol and n- butanol soluble portion of alcohol extract of Adina cordifolia leaves were tested against poplar defoliator, C. cupreata. N-butanol soluble fraction of leaves extracts of A. cordifolia was found to be most effective against the larvae as it gave 19.99, 18.56 and 10.60 average mortality out of 20 larvae at 2.0, 1.0 and 0.5 per cent concentrations, respectively. It is closely followed by bark and root extracts of D. stipulacea in acetone proved to be least effective among the five extractives tested. Alcohol seems to be better solvent in extracting active ingredient from root and bark of D. stipulacea as in both cases alcohol extract was remarkably more effective than that of acetone extractives (Ahmad et al., 1996a). A number of plant species have also been evaluated for their antifeedant properties against poplar defoliators. Acetone and alcohol extracts of bark and roots of D. stipulacea, leaves of Eucalyptus hybrid and Adina cordifolia along with ursolic acid and bryonolic acid were evaluated for their antifeedant potential against C. cuperata. Ursolic acid (separated from Eucalyptus hybrid leaves extract) has shown maximum antifeedant activity and gave over ninety two per cent protection of poplar leaves from its pests (Ahmad et al., 1997b). Bhandari et al. (1988) tested neem seed extractives on poplar defoliator, C.cupreata in laboratory. Neem seed extraction in various solvents such as acetone, chloroform, ethanol and methanol was attempted and the crude extracts thus obtained, were tried against larvae of poplar defoliator, C. cupreata Butler. Of all the extractives, the one obtained in methanol was found to exhibit a very high degree of antifeedant property at 0.125 and 0.025 per cent dilution, respectively. Seed extractives of bhekal (Prinsepia utilis) were also tested against poplar defoliator, C. cupreata for antifeedant properties. The extractive showed good biological activity at 0.25 per cent dilution against the third instar larvae of C. cupreata. Use of botanical pesticides is flourishing rapidly but with certain limitations. Limited commercial availability, comparatively higher cost and fast deactivation under field conditions are some of the constraints for their large scale use on long term basis. Biological Control Biological control of an insect pest is the device to suppress its population by employing its own natural enemies which may be parasitoides, predators or disease causing organisms, including bacteria, viruses, fungal pathogens or nematodes. 117 Parasitoids Use of parasitoids is gaining immense importance in biological control programme. They provide cost effective, environment friendly and biodiversity promotive way of controlling pests on sustainable basis. In a biocontrol programme of defoliators, a strategy can be formulated to explore the possibility of utilization of some exotic parasitoid species as well as to find out if natural enemy complex indigenously associated with the poplar defoliators are compatible to tackle the massive defoliation problem. In an effort to evaluate the efficiency of exotic parasitoids, seven species of egg parasitoids, Trichogramma, viz., T. achaeae, T. confusum, T. chilonis, T. exiguun, T. japonicum, T. perkensi and T. pretiosum were evaluated for parasitization against the eggs of poplar defoliator, Clostera cupreata. All Trichogramma species except T. confusum and T. japonicum were found to cause appreciable degree of parasitization to the eggs of C. cupreata. Higher parasitisation of 64.80 and 64.40 per cent was produced by T. perkensi and T. achaeae respectively, closely followed by T. chilonis, T. pretiosum and T. exiguum with 58.40, 54.20 and 52.40 per cent parasitization, respectively. However, T. japonicum did not accept the eggs of poplar defoliators even after repeated efforts with many pairs of parasitoids. Biology of the parasitoids was also studied in their new host. Effect of varying temperatures was seen on their life cycle and parasitization capability. The studies showed that all the six species of Trichogramma successfully completed their life cycle in the eggs of C. cupreata taking a period of 8 to 10 days. T. achaeae took comparatively less time (8.2 days) followed by 8.40, 8.60, 8.80 and 9.20 days taken by T. exiguum, T. chilonis, T. pretiosum, and T. perkensi, respectively. Low temperature conditions considerably extended the time period of parasitoids’ development but does not affect their reproductive potential. Fresh eggs of the host were found most suitable for the acceptance by the parasitoids (Ahmad, 1992). Efforts have been made to explore the natural enemy complex indigenously associated with the poplar defoliators. Extensive regular surveys were conducted over the years to the main poplar growing area in northern India including Tarai region of Uttarakhand, Uttar Pradesh and Haryana to collect regular monthly samples. These surveys yielded rich parasitoids and predator fauna associated with the defoliators. Four egg parasitoids; i.e., Telenomus colemani, Trichogramma chilonis, Ooencyrtus Iucina and Pediobius sp.; three larval parasitoids, AIeiodes percurrens, EupIemus sp. and one unidentified Ichmeumonid and two pupal parasitoids; i.e., Brachymeria euploeae and Brachymeria sp. were recorded parasitising on C. cupreata. Six parasitoid 118 species including Teienomus colemani, Trichogramma chilonis, Pediobius sp., Aleiodes percurrens, Eupelmus sp. and Brachymeria sp. were recorded for the first time (Ahmad et al., 1997a). While parasitising capability of Pediobius is yet to be confirmed, T. colemani seems to be a promising parasitoid species. Presence of T. colemani in the field was relatively common and has also been reared in the laboratory on its natural host. Among three larval parasitoids, A. percurrens was common on both defoliating species; i.e., C. cupreata and C. fulgurita although in low percentage ranging 2-9 per cent. The species was successfully reared in the laboratory on both the host larvae. A. percurrens presents sufficient scope for its exploitation as a biocontrol agent for the control of poplar defoliators. Other two larval parasitoid species were very scanty and require detail study before arriving at any conclusion regarding their status as the biocontrol agents. Two chalcidid species, Brachymeria euploeae and Brachymeria sp. were recorded as pupal parasitoids. Their presence in the field was very rare and insufficient for conducting laboratory experiments. The parasitoids might prove promising for exploitation as biocontrol agents in view of their capability of parasitizing last stage of the larva and also pupa. The parasitized pupae are easy to handle and also to transport. The above findings indicate sufficient scope for detail study in respect of a number of parasitoids as promising bio-control agents which later can be attempted for mass rearing. Predators Canthecona furcellata, although a polyphagous species, has frequently been observed in poplar nurseries and plantations throughout growing season along with the presence of defoliator’s larvae. Although population of the bug is much lower than the Clostera larvae, but it is higher than other predators including some species of preying mantids present in the poplar nurseries and plantation. Bug has often been observed preying on the Clostera larvae in the field despite the presence of other defoliating larvae including pyralids, geometrids, lymantrids, etc. This indicates its predatory preference towards Clostera larvae. Detailed study was conducted on preying potential of different nymphal instars, as well as adult, against the larvae of C. cupreata. Except first instar nymphs all remaining nymphal instars and adult are predaceous on C. cupreata larvae. A bug during its whole development and adult period ENVIS consume on an average number of 159.98 second instar larvae or 115.74, 89.68 or 86.535 larvae belonging to third, fourth or fifth instar, respectively (Ahmad et al., 1996b). Bug can easily be reared in the laboratory on the larvae of Clostera spp. as well as on other insects. Sycanus collaris Fabr. (Hemi: Reduviidae) was also recorded preying on Clostera spp. (Singh, 1998). Pathogenic Micro-Organisms Use of micro-organisms for the suppression of pest problem is gaining prominence in view of adverse impact of pesticides to the environment. Natural epizootic occurs among the immature stages of C. fulgurita and the pathogen has also been isolated from the diseased larvae (Sen Sarma and Ahmad, 1984). Disease pathogen was found to be NPV of sub group A of the genus Baculovirus which is claimed to be host specific. The disease was characterised by colour change and rapid disintegration of the infected larvae. The number of polyhedral inclusion bodies (PIBs) per larva ranged from 0.37 x 109 to 2.92 x 109. Artificial infection of the disease to the healthy larvae could be achieved by feeding them with poplar leaves sprayed with crude suspension of NPV. Cross infectivity tests confirmed the host specificity of the pathogen. The natural incidence of the disease among the laboratory breed larvae was 42.7 ± 7.7 per cent (Ahmad and Sen Sarma, 1983). NPV has also been observed infecting the larvae of prime defoliator of poplar, C. cupreata in the field as well as in the laboratory culture of the insect (Ahmad et al., 1998). It indicates variable infecting behaviour of the virus causing concern to its host specificity. Studies on various aspects of NPV from its infectivity to host range, intensity of infection and variability of conditioning are important areas which need further investigations to confirm its host range and to develop techniques for culture preservation and field application. Integrated Insect Pest Management IPM programme is a comprehensive system that utilises all suitable techniques and methods of pest prevention and suppression to maintain pest population below economic injury level. Thus, an IPM programme must be planned along with the establishment of the plantation and to continue till the felling. Mathur (1977) had emphasised the integrated approach of various control methods to contain the insect problems in various tree species and summarised a few examples including management of sal heart wood borer, Hoplocerambyx spinicornis, teak skeletoniser, Eutectona Forestry Bulletin, 12(1), 2012 machaeralis, teak defoliator, Hyblaea puera and deodar defoliator, Ectropis deodare. His main emphasis was to integrate mechanical approach with the use of pesticides. He also advocated the introduction of parasitoids and predator species. Epidemics of the major insect species of important tree species are still occurring periodically. Such incidences are suggestive of some gap in the adoption of integrated approach and necessitate alternate methods and combination of devices. In spite of our knowledge of various effective approaches of pest control, epidemic insect outbreak is dependently controlled by the large scale application of insecticides in the name of modern fourth generation pesticides. Epidemics of teak and deodar defoliators were controlled by aerial spraying of insecticides (Singh, 1980; Singh et al., 1989). Sal heartwood borer has caused phenomenal epidemic in recent past in Madhya Pradesh contributing to a national loss which runs in millions of rupees. Such instances might not be interpreted as failure of IPM programme. In fact, it should be attributed to the negligence, ignorance, poor planning and lack of perception. Non toxic approaches as has been detailed above are of sufficient potentiality to contain any pest outbreak. IPM is required to be perceived in its true sense. It emphasizes the need to have complete knowledge of the pests’ bio-ecology as has been lettered with surveillance, and the complexity of the situation which warrant adoption of specific measure. Such strategy, if followed on sustainable basis, would not allow the pest to rise beyond the economic threshold level. References Ahmad, D. and Ashraf, M. 1981. Notes on biology and habits of Chrysomela populi L (Col.: Chrysomelidae) in the forest of Kashmir. In: Symposium on Silviculture, Management. and Utilization of Poplars, Srinagar, 15-18 October 1979. Proceedings. Simla, Government of India Press. pp 142-143. Ahmad, M. 1992. Bio-efficacy of egg parasites, Trichogramma spp. against poplar defoliator, Clostera cupreata. Indian Journal of Forestry, 15(3): 198-202. Ahmad, M. 1993. Relative resistance in different clones of Populus deltoides to poplar defoliator, Clostera cupreata (Lepidoptera : Notodontidae). Annals of Forestry, 1(1): 1-12. Ahmad, M. and Faisal, M. 2004. First record of Eupterote undata (Lepidoptera: Eupterotidae) infesting Populus deltoides. Annals of Forestry, 12(2): 285-286. 119 Ahmad, M.; Ahmad, M.J. and Mishra, R.K. 1997a. Indigenous microhymenopteran parasitoid species associated with poplar defoliator, Clostera cupreata (Lepidoptera: Notodontidae). Annals of Forestry, 5(1): 26-34. Ahmad, M.; Dayal, R. and Borai, P. 1996a. Evaluation of insecticidal properties of Dalbergia stipulacea against poplar defoliator, Clostera cupreata (Lepidoptera: Notodontidae). Annals of Forestry, 4(1): 47-51. Ahmad, M.; Dayal, R.; Mishra, R.K. and Dobhal, P.C. 1997b. Antifeedant potency of some plants produce against defoliating pest of poplar, Clostera cupreata. Indian Forester, 123(9): 821-826. Ahmad, M.; Mishra, R.K.; Ahmad, M.J. and Manoj Kumar. 1999. Suppression of NPV infection in the laboratory culture of poplar defoliator, Clostera Cupreata (Lepi.: Notodontidae). Indian Journal of Forestry, 22(1-2): 53-56. Ahmad, M.; Singh, A.P.; Sharma, S.; Mishra, R.K. and Jamal, M. J. 1996b. Potential estimation of predatory bug, Canthecona furcellata Wolff (Hemiptera : Pentatomidae) against poplar defoliator, Clostera cupreata (Lepidoptera: Notoqontidae). Annals of Forestry, 4(2): 133-138. Ahmad, S.I. and Sen-Sarma, P.K. 1983. Investigation on a newly recorded nuclear polyhedrosis virus of Pygaera fulgurita Wlk. (Notodontidae: Lepidoptera). I. Nature of disease and insect-virus interactions. Journal of Entomological Research, 7(2): 150-153. Barnes, D.K. and Freyre, R.H. 1966. Recovery of natural insecticide from Tephrosia vogelii. I. efficiency of rotenoid extraction from fresh and oven dried leaves. Economic Botany, 20(3): 279-289. Beeson, C.F.C. 1919. The food plants of Indian insects. Part III. Indian Forester, 45: 212-323. Beeson, C.F.C. and Bhatia, B.M. 1939. On the biology of the Cerambycidae (Coleopt). Indian Forest Records (New Series) Entomology. Delhi, Manager of Publication. pp. 174-176. Beeson, C.F.C 1941. The ecology and control of the forest insects of India, and the neighbouring countries. Dehradun, Vasant Press. 1107p. Benner, J.P. 1993. Pesticidal compounds from higher plants. Pesticide Science, 39(2): 95-102. Bhandari, R.S.; Lal, J.; Ayyar, K.S. and Singh, P. 1988. Effect of neem seed extractives on poplar defoliator Pygaera cupreata Butler (Lepidoptera: Notodontidae) in laboratory. Indian Forester, 114(11): 790-795. 120 Bhatt, A.A. and Qadri, S.T. 1981. Significant insect pests of poplars in nurseries and avenue plantations. In: Symposium on Silviculture, Management and Utilization of Poplars, Srinagar, 15-18 October 1979. Proceedings. Simla, Government of India Press. pp. 144-150. Browne, F.G. 1968. Pests and diseases of forest plantation trees. Oxford, Clarendon Press. 1330p. Chakrabarti, S. 1977. Chaitophorinae (Aphididae; Homoptera) of India with descriptions of three new species from North West India. Oriental Insects, 11(2): 205-224. Chatterjee, P.N. and Sen-Sarma, P.K. 1968. Important current problems of forest entomology in India. Indian Forester, 94(1): 112-117. Chatterjee, P.N. and Thapa, R.S. 1964. Insect pests of fast growing tree species 1. Preliminary investigations on poplar stem and root borer, Apriona cinerea Chev. (Coleoptera: Lamiidae) in New Forest. Indian Forester, 90(10): 681-687. Chatterjee, P.N.; Singh, P. and Prasad, G. 1969. Insect pests of fast growing tree species. II-Effect of various fumigants on Poplar stem borer, Apriona cinerea Chevrolet (Lamiidae) in New Forest plantations. Indian Forester, 95(5): 369-371. Chaturvedi, A.N. 1981. Poplar farming in Uttar Pradesh. U.P. Forest Bulletin No. 45. 42p. Choudhary, G.U.; Choudhary, M.L. and Malik, N.K. 1970. Survey of insect fauna of forests on Pakistan, Vol. 2. Peshawar, Biological Sciences Research Division, Pakistan Forest Institute. 205p. Curtis, C.F. 1990. Appropriate technology in vector control. Boca Raton, CRC Press. David, S.K.; Narayanan, K. and Rajasingh, S.G. 1971. Records of aphids in India. Madras Agricultural Journal, 53(5): 372-374. Dhaliwal, G.S.; Dilawari, V.K. and Saini, R.S. 1993. Host plant resistance to insects: Basic concepts. In: Dhaliwal, G.S. and Dilawari, V.K. Eds. Advances in host plant resistance to insects. New Delhi, Kalyani Publishers. pp. 393-422. Gao, R.T.; Qin, X.X.; Li, J.Z.; Hao, W.Q. and Wang, X.Z. 1985. A preliminary study on the relationship between artificial defoliation of poplar trees and their growth. Scientia Silvae Sinicae, 21: 199205. Higuchi, M. 1972. A taxonomic study of the subfamily Callipterinae in Japan (Homoptera: Aphididae). Insecta Matsumurana, 35(2): 19-21. ENVIS Kaul, R.N. and Sharma, K.K. 1982. Status report on poplar. In: Workshop on Poplars, Haldwani, 23-24 January. Proceedings. pp. 21-55. Kogan, M. 1982. Plant resistance in pest management. In: Metcalf, R.L. and Luckman, W.H. Eds. Introduction to pest management. New York, John Willey. pp. 93134. Lohani, D.N. 1976. Current status of poplar trials in Uttar Pradesh. U.P. Forestry Bulletin No. 34. Mani, M.S. 1955. Plant galls from the Himalayas. Marcellia, 30 (Suppl.): 23-48. Mani, M.S. 1973. Plant galls of India. Macmillan, India. 354p. Maity, S.P. and Chakrabarti, S. 1981. On the poplar inhabiting aphids (Homoptera: Aphididae) of India and adjoining countries with notes on some species. Entomon, 6(4): 297-305. Mann, G.S. 1981. New record of Pygaera restitura Walker (Notodontidae: Lepidoptera) on poplar. Journal of the Bombay Natural History Society, 78(2): 413. Mathur, R.N. and Singh, B. 1960. A list of insect pests of forest plants in India and adjacent countries. Indian Forest Bulletin (New Series) Entomology, 171(7): 1-130. Muirhead-Thomson, R.C. 1948. The effect of house spraying with pyrethrum and DDT on Anopheles gambiae and A. meles in West Africa. Bulletin of Entomological Research, 38: 313-314. Pruthi, H.S. and Batra, H.N. 1960. Important fruit pests of north-west India. ICAR Bulletin No. 80. New Delhi, ICAR. 113p. Rawat, B.S. 1979. Pests and diseases of poplars in U.P. tarai. In: Symposium on Silviculture, Management and Utilization of Poplars, Srinagar, 15-18 October 1979. Proceedings. Simla, Government of India Press. pp. 126-129. Richards, W.R. 1967. The Peterocomma of Canada and Greenland with notes on the phylectic position of Pterocommatin (Homoptera: Aphididae). Canadian Entomologist, 99(10): 1015-1040. Rishi, N.D. 1977. Survey and studies on the pests of silvicultural importance in Kashmir. In: Oriental Entomology Symposium, 2nd, Madras, 23-27 March 1977. Proceedings. pp. 21-22. Rishi, N.D. 1979. Additional records of aphid fauna (Homoptera: Aphididae) from J&K (India). In: Symposium on Recent Trends in Aphidological Studies, Bhubaneswar, 9-12 June. Proceedings. Bhubaneswar, Zoological Society of Orissa. Rishi, N.D. 1981. Insect pests of poplars in Kashmir Valley. In: Symposium on Silviculture, Management and Forestry Bulletin, 12(1), 2012 Utilization of Poplars, Srinagar, 15-18 October 1979. Proceedings. Simla, Government of India Press. pp. 123-125 Roychoudhury, N.; Joshi, K.C. and Rawat, P.S. 1994. A new record of Chrysocoris purpureus Westwoood (Heteroptera: Scutelleridae) on poplar, Populus deltoides Bartr. ex Marsh. Indian Forester, 120(12): 1126-1128. Russel, P.F. and Knipe, F.W. 1941. Malaria control by spray killing adult mosquitoes. Third session’s results. Journal of the Malaria Institute of India, 4: 181197. Saxena, R.C. 1986. Biochemical basis of insect resistance in rice varieties. In: Maurice, G.B. and Paul, A.H. Eds. Natural resistance of plants to pests. Washington, American Chemical Society. Saxena, R.C. and Pathak, M.D. 1979. Factors affecting resistance of rice varieties to the brown plant hopper, N. lugena. In: Annual Conference of Pest Control Council of Phillipines, 8th, Bacold, 18-20 May 1977. Proceedings. Laguna, International Rice Research Institute. pp. 304-317. Sen-Sarma, P.K. and Ahmad, S.I. 1984. A polyhedral virus infecting poplar defoliator Pygaera fulgurita (Walk.) (Noctuidae: Lepidoptera). Indian Journal of Entomology, 46(1): 112-114. Sen-Sarma, P.K. and Gupta, B.K. 1979. Insect pests of poplars. In: Symposium on Silviculture, Management. and Utilization of Poplars, Srinagar, 15-18 October 1979. Proceedings. Simla, Government of India Press. pp. 121-122. Senior White, R. 1945. House spraying with DOT and Pyrethrum extract compared first. Journal of the Malaria Institute of India, 6: 83-87. Seth, S.K. 1969. Poplar trials in Uttar Pradesh. U.P. Forestry Bulletin No. 34. 106 p. Sharma, B. and Bhatia, S. 1996. Management and control of Apriona cinerea Chev. (Coleoptera: Cerambycidae): A stem borer of poplar in Jammu Forests. Indian Forester, 122: 383-385. Sharma, G.C. and Sharma, K.C. 1993 Pulvinaria vitis L., a new record of scale insect on poplar (Populus ciliata) in India. Journal of Entomological Research, 17(3): 227. Singh, A.P. 1991. Orgiya postica (Lepidoptera: Lymantriidae), a new pest of Populus deltoides. Indian Forester, 117(12): 1083-1084. Singh, A.P. 1998. Sycanus collaris Fabr. (Reduviidae: Hemiptera), A new predator of Clostera spp. on Populus deltoides. Indian Forester, 124(2): 172. 121 Singh, N.P.; Prakash, O. and Singh, R.P. 1987. Present status of poplars in Tarai belt of U.P. In: Khosla, P.K. and Kohli, T.K. Eds. Social forestry for rural development. Solan, ISTS. pp. 165-166. Singh, P. 1963. San Jose scale menace to hill orchards. Indian Horticulture, 716: 780. Singh, P. 1980. Aerial spraying of chemicals to control teak defoliators. In: Forestry Conference, 2nd, Dehradun, 6 -19 January 1980. Proceedings. Delhi, Controller of Publications. Singh, P. and Prasad, G. 1985. Poplar stem borer Apriona cinerea Chev. (Coleoptera: Cerambycidae), its biology, ecology and control. Indian Forester, 111(7): 517-524. Singh, P. and Singh, S. 1975. Insect pests and diseases of poplars in developing countries. In: World Technical Consultation on Disease and Insects, 2nd, New Delhi, 7 April 1975. Proceedings Rome, FAO. Singh, P. and Singh, S. 1986. Insect pests and diseases of poplars. Dehradun, FRI. 74p. Singh, P.; Bhandari, R.S.; Fasih, M.; Ganga Prasad; Tyagi, B.D.S.; Misra, B.M. and Mishra, R.K. 1989. Epidemic deodar defoliator Ectropis deodarae Prout (Lepidoptera: Geometridae) in Kamraj Forest Division J.K. and its control by aerial spraying of fenitrothion. Indian Forester, 115(7): 459-474. Singh, P.; Rawat, D.S.; Misra, R.M.; Fasih, M.; Prasad, G. and Tyagi, B.D.S. 1983. Epidemic defoliation of poplars and its control in Tarai Central Forest Division, Uttar Pradesh. Indian Forester, 109(9): 675-693. Snelling, P.O. 1941. Resistance of plants to insect attack. Botanical Review, 7: 543-586. Sohi, A.S. 1989. Insect pests of poplar. In: Seminar on Forest Protection, Dehradun, 29-30 June 1989. Proceedings. Sohi, A.S. 1990. Insect pests of poplar and their management. Key insect pests of India, their bioecology with special references to integrated pest management. New Delhi, I.C.A.R. pp. 295-306. 122 Sohi, A.S. and Mann, J.S. 1986. Kusala salicis (Ahmed), (Cicadellidae : Typhlocybinae) - A new pest of Populus in the Punjab, India. Annals of Biology., 2 (2) : 202. Sohi, A.S.; Singh, H. and Sandhu, G.S. 1987. Closterarestitura (Walker) (Lepidoptera: Notodontidae), a defoliator of poplar (Populus sp.) in the Punjab and its chemical control. Journal of Tree Sciences, 6(1): 3033. Stebbing, E.P. 1914. Indian forest insects of economic importance. Coleoptera. London, Eyre and Spottiswoode. Tewari, D.N. 1993. Poplar. Dehradun, Surya Publications. 321p. Thakur, M.L. 1981. New and little known insect pest of exotic poplars and their enemy complex in the Bhabar-Tarai Region, Uttar Pradesh. In: Symposium on Silviculture, Management and Utilization of Poplars, Srinagar, 15-18 October 1979. Proceedings. Simla, Government of India Press. pp. 130-136. Thakur, M.L. 1999. Insect pest status of poplars in India Indian Forester, 125(9): 866-872. van der Goot, P. 1916. On some undescribed aphids from the collection of the Indian museum. Records of the Indian Museum, 12: 1-4. Verma, T.D.; Dhaliwal, H.S. and Verma, A.K. 1983. Insect-pestcomplex of poplars in India and its management. In: Symposium on Improvement of Forest Biomass, Nauni. Proceedings. Solan, ISTS. pp. 463-468. Verma, T.D. and Khurana, D.K. 1985. Bionomics and control of poplar stem borer, Apriona cinerea Chevrolat (Lamiidae: Coleoptera) in agroforestry plantations. In : Khosla, P.K.; Puri, S. and Khurana, D.K. Eds. Agroforestry systems: A new challenge. Solan, Indian Society of Tree Sciences. pp. 237-240. Vijay Veer and Chandra, A. 1984. Insect pests in nurseries and plantations of Populus deltoides in Assam and Bengal. Indian Forester, 110(7): 640-643. z ENVIS Studies on Wood Quality of Poplar Vimal Kothiyal Research Planning Division, Indian Council of Forestry Research and Education, Dehradun - 248 006 Introduction P oplar (Populus deltoides) is an extensively planted agroforestry tree species in northern India. Its wood for industrial and domestic use is available from Jammu and Kashmir, Himachal Pradesh, Punjab, Haryana, Uttarakhand and Uttar Pradesh. After eucalypts, poplar is the major source of woody raw material from plantations. Research organisations in India have been working on its utilisation aspects and have generated voluminous data, ranging from strength properties to seasoning behaviour, preservation, ammonia fumigation, wood working and finishing qualities in addition to peeling characteristics and manufacture of panel products. The species is the main source of raw material from trees outside forests in northern India. P. ciliata is found and mainly grown in hilly tracts of Jammu and Kashmir, Himachal Pradesh and Uttarakhand. Physical and Mechanical Properties Poplar has been explored for its material characteristics and utilisation aspects for various end use suitability Forestry Bulletin, 12(1), 2012 The first ever article on strength properties of three Populus species was published by Shukla and Sangal (1986). Preliminary strength data generated on three logs of P. deltoides; 2 logs each of P. casale and P. heidmij were reported in this paper. Shukla et al. (1989) reported physical and mechanical properties of P. ciliata timber obtained from Theog Division, Himachal Pradesh. Later on, as more and more material became available for commercial exploitation, a need was felt to generate more information on its properties and end utilization. Timber testing work started on a larger scale to assess the wood quality of material from various sources including clones. Series of research articles were published by various researchers on P. deltoides: Shukla et al. (1990) on strength properties of 16-yr old IC clone; density and strength properties variation from pith to periphery in 15-yr old by Shukla et al. (1991); bottom to top variation of strength properties in 10-yr old G3 clones by Shukla et al. (1995-96); Shukla and Singh (1995) tested 10-yr and 15-yr old P. deltoides from Dehradun and Haryana. Shukla et al. (1996) studied the effect of different preservative formulations/retention on strength properties of P. deltoides. Rajput (1996) brought out a comprehensive review on the work carried out on the utilisation aspects of P. deltoides timber till 1996. Dubey et al. 123 (1997) utilised non-destructive vibration test method for estimating modulus of elasticity of P. deltoides timber. Tree improvement by way of clone development and assessing their quality for utilization was seriously taken up at FRI laboratory. Era after 1997 was marked with the studies devoted to characterisation of poplar clones. In this series Rajput et al. (1997) published on specific gravity and compressive strength variation in 7 1/2-yr old 20 clones developed by M/s Wimco Seedling Ltd., Rudrapur and Shukla et al. (2000) published strength data on the same clones; Jain and Khanduri (2003) reported strength data on six clones of 10-yr old and subsequently Kothiyal et al. (2005) reported strength data on 10-yr old 12 clones. As on today strength data on 20 clones (two tree each) of 71/2 -yr old (G-48, G-3, S7C13, St-63, St-240, S7C3, 111412, St-121, 3650, St-288, St-153, St-100, St-71, 110610, 111234, 112107, St-163, 6238, 110412); five logs of 16-yr old IC clone; six clones (two tree each) of 10-yr old (D121, G3, G48, S7 C4, S7 C15, S7 C20); 12 clones (one tree each) of 10yr age (L12/82, L13/82, L34/82, L49/82, L52/82, L62/84, L71/ 84, L75/84, L188/84, L200/84, L247/84, L290/84) have been generated. Clones G3 and G48 have been studied in two age groups; i.e., 7 and 10 years, Table 1 depicts the range (maximum and minimum) of values of strength properties obtained for all the material studies in India both in green and air-dry conditions. It is quite evident that there is wide variation in strength properties, which can be gainfully utilized. Physical and mechanical properties of some of the best performing and worst performing clones (in terms of strength properties) in green condition is also given in Table 1. From the strength data, it is evident that strength properties of material grown at Rudrapur are better than the one from Haldwani (e.g. Clone G3 and G48). Overall, at Haldwani, S7C4 has performed better followed by G48 and L 290/84 whereas L75/84 and IC are worst performing in terms of strength properties. Overall taking poplar from both the locations together, it is clear that clone S7C3 from Rudrapur has given the best properties, highest specific gravity and low FSP. This is followed by S7C4, which is having low specific gravity but higher strength. These two clones are followed by St-63, G3 and G48. L75/84 and IC are poorest in strength. Among the clones studied, further multiplication trials of S7C3, S7C4, St-63, G3 and G 48 along with assessment of wood quality need to be done. Table 1. Physical and mechanical properties of P. deltoides Property Place Age (Yr) No of logs/tree Specific gravity Weight (kg/mm3) Shrinkage (%) Radial Tangential End FS Point (% mc) Static bending FS at EL (kg/cm2) MOR (kg/cm2) MOE (103kg/cm2) Impact bending: FS at EL (kg/cm2) MOE (103kg/cm2) Compression// to grain CS at EL (kg/cm2) MCS (kg/cm2) Compression ⊥ to grain CS at EL (kg/cm2) Hardness, kg Radial Tangential End Shear // to grain Radial, (kg/cm2) Tangential, (kg/cm2) Tension // to grain TS at EL (kg/cm2) MTS (kg/cm2) MOE (kg/cm2) Tension ⊥ to grain Radial (kg/cm2) Tangential(kg/cm2) Cleavage Radial (kg/cm) Tangential (kg/cm) Green condition 0.355-0.511 697-976 Air-dry condition 0.381-0.528 427-605 3.4-5.9 7.3-10.3 11.9-12.9 24.3-33.4 S7C3 St 63 R 7 2 0.511 929 R 7 2 0.448 955 R 7 2 0.433 952 5.3 9.1 4.7 9.8 3.6 8.6 4.8 10.3 29.9 30.0 26.8 G3 G48 H 10 2 0.362 853 R 7 2 0.442 914 H 10 2 0.405 814 S7C4 L290/84 L71/84 L13/82 St-240 L75/84 IC H 10 2 0.410 828 H 10 1 0.422 834 H 10 1 0.392 766 H 10 1 0.397 940 R 7 2 0.408 829 H 10 1 0.355 848 H 16 5 0.398 976 - 4.2 9.7 5.0 7.8 32.3 26.8 132-346 249-636 17.1-98.9 162-439 257-859 44.0-112.8 315 636 98.3 296 537 71.7 260 448 59.9 132 297 54.1 268 460 67.1 219 389 62.9 295 406 90.7 249 437 63.5 198 370 30.0 181 331 33.6 228 386 49.7 140 249 17.1 220 341 46.0 287-701 26.9-111.4 295-932 39.6-138 744 98.5 636 74.1 557 58.2 484 47.4 596 74.1 596 71.7 701 73.0 464 37.2 447 51.2 445 32 503 61.8 349 26.9 390 34.4 38-214 62-297 94-219 164-458 201 297 145 251 113 179 84 134 140 205 131 198 155 219 55 94 153 189 81 120 153 193 38 62 171 15-48 28-79 37 48 38 20 41 31 35 29 25 32 28 20 15 195-372 183-382 175-393 150-460 172-524 182-552 310 325 351 372 382 393 302 341 299 214 221 238 286 323 299 274 280 280 259 277 284 203 199 231 242 253 251 228 217 175 260 264 270 199 207 203 195 183 182 25.1-74.4 25-1.8.06 39.9-110.3 52.0-99.0 74.4 84.8 65.7 68.5 57.5 60.1 44.5 44.7 63.5 67.3 62.6 70.8 64.5 66.9 29.4 32.0 48.8 60.5 28 28.1 50.1 59.8 25.1 25.1 52.5 54.8 179-411 512-685 45.3-57 679 730 80.1 - 13.0-36-9 13.3-42.1 16.7-45.8 20.4-55.7 26.1 34.3 27.5 32.4 25.1 32.8 18.0 20.7 36.9 42.1 20.8 23.1 20.8 23.1 19.2 19.5 15.6 19.2 13.5 17.5 15.2 15.9 14.1 18.0 25.5-48 29.4-43 43.6-72.5 42.9-87.0 49.9 52.8 48 43 46.0 43.5 44.4 46.2 41.8 46.2 46.2 42.6 46.2 42.6 37.9 40.6 40.6 41.8 37.8 41.7 39.5 45.0 27.8 35.7 282 512 55.3 16.3 15.4 FSP- Fibre saturation point; H- Haldwani, R- Rudrapur. 124 ENVIS Wood Working and Carving Quality of Poplar of stresses a large proportion of this material is prone to severe distortion coupled with warping during seasoning due to low resistance of planks to drying stresses. When logs are sawn by conventional Cant method to get the desired size of planks, growth stresses cause crook to occur at the headrig. Further, additional crook develops in drying because of non-uniform longitudinal shrinkage and the inherent low resistance of planks to the drying stresses. Studies on air and kiln drying behaviour of P. deltoides revealed that though it is not difficult to dry the material, and is prone to severe distortion. The major defects observed in all seasoning are bow, crook, honeycombing. In conventional kiln seasoning also, as per the usual schedule, the species has shown severe bow, spring and twist. Hardly any plank was free from warping degrade of one kind or the other. In addition, several planks developed moderate to severe collapse. Planks free from collapse or having slight collapse belonged to outer positions in the log. However, a reconditioning treatment for 6 hr showed appreciable recovery in the collapse. The values of degrade observed in one of the kiln drying experiments were recorded and are presented here in Table 4 along with permissible values to demonstrate the ineffectiveness of conventional seasoning method for this species (Pandey and Kambo, 1991). The study was undertaken to estimate the distortion due to growth strains in logs of this species based on diametric slabs sawn out of the log. The maximum values of peripheral tension and compression strains recorded on diametric slabs (Sharma et al., 1990) taken from three consecutive bolts of a single log of P. deltoides are given in Table 5. Corresponding values recorded for eucalypts hybrid in the earlier study are also detailed for comparison. The strains are larger in magnitude both in tension and compression than in eucalypts hybrid. The wood is much weaker than eucalypts hybrid and a given stress in it is expected to be associated with larger strains. There is no indication Working and carving qualities play a vital role in the judicious utilisation of timbers which vary in anatomical features, physical and mechanical properties, durability, seasoning behaviour and other characteristics for furniture, joinery, turning, handicraft, etc. FRI has evaluated the working and carving qualities (Table 2 and 3) for P. deltoides and P. ciliata (Shukla et al., 1991). The working qualities are reviewed under six major wood working operations namely planning, boring, mortising, shaping, turning and sanding. Carving behaviour of wood is evaluated under punching, chiselling, fret saw work and scooping. Staining Poplar (P. deltoides) Using Ammonia Fumigation and Bark Extract Work has been carried out on wood staining trials conducted on pre-finished surface of plain looking P. deltoides timber using aqueous bark extract of Terminalia alata as staining material (Badoni et al., 1990). It was observed that dip treatments (0.5 to 120 hr) stain the pre-finished surface of P. deltoides in reddish brown shades in varying degree with prominent surface figure. Ammonia fuming of stained specimens further darkens the wood to blackish brown shades. Out of the various combinations tried, pre-ammonia fuming (12 hr) followed by swabbing/spraying/short interval dipping in the bark extract was found very effective in achieving golden brown shades and prominent surface figure near to the natural look of teak (Tectona grandis). Gupta et al. (2007) conducted some experiments on gloss and ammonia fumigation film forming and penetrating types of finishes on poplar surface. Timber Drying One of the major problems encountered in utilization of plantation grown poplar is that during sawing, with release Table 2. Working qualities of some Indian timbers Species Tectona grandis P. deltoides P. ciliata Specific gravity Best cutting angle in planning (o) 0.57 0.55 0.40 25 20 15 Overall performance (CRF) 100 39 42 Ease of working (ease factor) 100 119 117 Working quality index 100 94 92 Grouping based on overall performance I II III Comparative performance (turning) 100 10 52 Table 3. Data on carving quality of some timbers taking teak as hundred S p ecific g ra vity O verall co m p a ra tive p erform a n ce u n d er co m b in ed w o o d w o rkin g o pera tio n s O ve r all co m p a r a tive p erform a nce u n d er ca rv ing o p era tio n s C a rving q u ality in d ex T . g ran d is 0 .5 5 6 1 00 1 00 1 00 P . d elto id e s 0 .5 5 0 39 39 52 P . cilia ta 0 .4 0 0 42 39 52 S p ecies Forestry Bulletin, 12(1), 2012 125 Table 4. Observed vs permissible degrade of different kinds over length of 215 cm *during kiln drying Type of degrade Extent of degrade and (No. of planks) Permissible In sawing After kiln drying 8 mm 16 mm (2) Bow 7-8 mm (2) 8-11 mm (6) 3-5 mm (5) 3 mm and below (4) Nil (5) 10 mm Spring Not recorded 15-18 mm (3) 10-11 mm (4) 3 mm and below (5) Twist Nil (12) 20 mm (1) 63 mm 10-12 mm (5) 4-6 mm (2) 4 mm and below (4) 2.54 mm Cup Nil (12) 4-5 mm (3) 2-5 mm (2) Nil (7) * Estimated on proportional basis from permissible norms for 300 cm length Table 5. Maximum peripheral tensile strains and interior µE) in diametral slabs cut out compressive strains (µ of 3 consecutive bolts from a log of P. deltoides Bolt no. Mode of sawing of strips 1. Serially cut First radial half of slab Second radial half of slab Serially cut First radial half of slab Second radial half of slab Balanced tangentially sawn First radial half of slab Second radial half of slab Eucalyptus hybrid Serially cut First radial half of 3 slab Balanced tangentially cut 2. 3 Max. strains (μE = 10 -6 m/m) Peripheral Interior tensile compressive 388 290 610 312 406 810 260 432 652 652 100-296 298-328 272-316 116-186 from this preliminary test that balanced tangential sawing would reduce the level of strains in compression or in tension compared to the strains obtained in serial cutting of strips. This is at variance with the observations made on eucalypts hybrid in which balanced tangential sawing appreciably reduced compressive strains compared to serial cutting. This preliminary investigation suggests that radial or balanced tangential sawing as adopted for eucalypts hybrid can not be of utility in case of P. deltoides and modified sawing and drying techniques need to be evolved for this species to minimize growth stress induced warping problems. To overcome this problem, the Forest Research Institute, Dehradun has now developed a system of sawn wood manufacturing process known as saw dry rip (SDR). The saw-dry-rip (SDR) system for sawn wood manufacture was developed at Forest Products Laboratory, USA in 1978, for use with hardwoods, which generally have longitudinal growth stress problems. The technique aimed to control excessive warping in sawn timbers, which had to a great extent restricted low and medium density hardwoods from being used in the manufacture of structural lumber on commercial scale. In India saw-dry-rip technique was 126 successfully applied to Eucalyptus logs and the same was used in P. deltoides (Pandey and Kambo, 1993). In this study comparison of four sawing and drying treatments were made by evaluating warp (crook, bow and twist) based on the permissible limit at 12 per cent moisture content. The combination of SDR high temperature drying treatment produced the best result as the per cent of rejects of scantlings was found to be 5-8 per cent in comparison to other treatments where rejection ranged from 20-57 per cent. In this method first the logs are sawn in thick section slabs keeping the thickness of slabs equal to the width of desired ultimate planks. These slabs are then rough edged and are dried under high temperature as per schedule given below (Table 6). The slabs thus dried are ripped into planks of desired width (Pandey and Kambo, 1993). Pandey (1995) carried out studies on bulk flow and diffusion of moisture in Eucalyptus tereticornis and P. deltoides for predicting drying rate. Kishan Kumar et al. (2008) conducted vacuum press drying studies on P. deltoides and concluded that the timber can be successfully dried with considerable reduction in drying time. When the material is dried at high temperature, it is theorised that the lignin, which naturally bonds fibers together is plasticized and the stressed fibers slip to a neutral or unstressed position. The lignin then rehardens and wood is stress free. Table 7 gives the comparison of different drying schedule. The SDR and high temperature combination is much better suited for the processing of P. deltoides as the percentages of rejects were minimum due to warping. The possible reasons could be: 1. Stress balanced by slab sawing. 2. Wide planks restrain warp. 3. Drying stresses offset growth stresses. 4. Lignin plasticized at high temperature. Table 6. High temperature drying schedule Initial moisture content Dry bulb temperature Wet bulb temperature Duration Followed by reconditioning Dry bulb temperature Wet bulb temperature Duration Final moisture content More than 50% 102oC 90oC 96 hr 90oC 86oC 6 hr 12-15% Table 7. The comparative performance of drying by different methods Air seasoning 25 mm thick planks, 40-45 days Prone to severe distortion Kiln seasoning 25 mm thick planks, 6-7 days 28-57% rejection due to warp and honeycombing High temperature drying 100 mm thick slabs, 4 days 5-8% rejection due to warp ENVIS Storage of Poplar Logs End Utilization of Poplar Wood One of the major problems faced during storage of logs of poplar in the timber yard is discolouration and decay in wood due to fungal attack. Staining fungi cause mostly discolouration of the sapwood. The progress of staining fungi is very rapid and the entire poplar sapwood may become stained in course of one to a few weeks. Though strength properties of stained wood mostly remain unaffected, such wood is not liked because of its appearance. To avoid this problem, prophylactic treatment of the logs should be undertaken as soon as they reach the storage yard or at the felling site itself when transportation of logs from felling site to storage yard is not done immediately. The bark must first be removed completely for protective treatment before spraying thoroughly the entire surface with a 2.5 per cent water solution of sodium pentachlorophenate, boric acid and borax mixed in the ratio of 0.5: 1.1. The logs are, then, stacked on the ground under hygienic conditions. It must be remembered that this treatment is effective only if it is undertaken immediately after felling and cross cutting into logs. Once infection occurs, it is difficult to control it through prophylactic treatment. Beri et al. (1979) studied effect of preservatives on chemical constituents and pulping quality of P. deltoides logs during open storage. A number of studies have been conducted at FRI for finding various end uses of P. deltoides e.g pencil making (Rao et al., 1994; Rao, 1996), wood poles (Jain et al., 1990), packing cases (Shukla 1979). The study on lateral bearing strength in double and quardruple shear joints has also been conducted (Pruthi and Mamgain, 1994). Poplar has been recommended for doors and window shutters (Shukla, 1997), light furniture, packing cases, crates, sports goods, artificial limbs, pencil making and poles. Natural Durability and Preservative Treatment For rational utilization of any wood species, its natural durability and treatability should be known in advance. Experiments at FRI have been conducted to determine natural durability of poplar heartwood in Indian condition and treatability of the timber (Dev and Kainth, 1989; Kumar and Dobriyal, 1993, 1995; Dobriyal and Kumar, 1999: Dobriyal et al., 2001). Page and Gnanaharan (1999) studied the influence of wood moisture on the preservative treatment of New Zealand grown poplar. P. deltoides has been classified as non durable timber and is easily treatable and falls under treatability class ‘a’. Field experiments at FRI test yard have been conducted on treated samples with coal tar creosote- fuel oil mixture (50:50) at three levels of absorptions and Ascu/CCA/As2O3, 2H2O: CuSO4, 5H2O; Na2Cr2O7, 2H 2O (in the ratio of 1:3:4) at three retention levels. No uniform trend has been observed on the effect of different preservative formulations/retentions on strength properties although at lowest retention of 4 kg/ m3 has given maximum values of strength properties (Shukla et al., 1996). Forestry Bulletin, 12(1), 2012 Reconstituted Wood Products from Poplar A brief review of the research carried by FRI, Dehradun has been compiled by Singh and Negi (2001) and the same is reproduced here in addition to work carried out by Indian Plywood Industry Research and Training Institute (IPIRTI), Bangalore. The current research is focused on combining plywood with other plantation species such as Eucalyptus and Paulownia and utilising lops and tops of poplar. Veneer, Plywood and Blockboard Optimum conditions for peeling: Uniformity of thickness in veneer is of great importance for its subsequent use in plywood, laminated wood,etc. Lack of uniformity in thickness of veneer may result in poor bonding with adhesives. Keeping in view the above, optimum conditions for peeling poplar into veneer having uniformity in thickness, tightness and strength were studied (Shukla et al., 1992). IPIRTI, Bangalore also studied the peeling drying and drying characteristics of poplar (Indian Plywood Industry Research and Training Institute, [n.d.]). Considering the results obtained during peeling of two species viz., P. deltoides and P. ciliata the optimum conditions of peeling are given in Table 8. Table 8. Optimum conditions of peeling Veneer thickness (mm) Temperature of log conditioning (oC) Speed of peeling (m/min) Knife angle P. ciliata 1.61 55 39.62 91.2o P. deltoides 1.61 55 45.72 90o Plywood and allied products: P. deltoides obtained from Lalkuan, Haldwani (Uttaranchal) and P. ciliata from Kothani Range, Shimla (H.P.) were studied for its suitability for making various grades of plywood and blockboards. Both the species did not offer any gluing problem and satisfactory glue bond could be obtained with common commercial adhesives like, PF and UF for making plywood. Experiments on 3 and 5 ply 127 indicated that the species is easy to treat with water borne preservatives and fire retardant chemicals and adequate loading of the chemicals can be obtained. Treatment with preservative (copper-chrome-arstenate) and fire retardant-cum antiseptic chemical (ammonium phosphate, copper sulphate and sodium dichromate) did not adversely affect the glue bond. The species is suitable for making, (a) plywood for general purposes, (b) marine plywood, (c) plywood for concrete shuttering work, (d) preservative treated plywood, (e) fire retardant plywood and also for (f) blockboards (Shukla et al., 1986; Rajawat et al., 1989; Dimri et al.,1990, 1993 ). The service life of plywood from P. deltoides can be increased by adopting glue line poisoning using arsenic tri-oxide mixed in PF glue. The glue shear strength of treated as well as untreated plywood with three different thickness of veneers; i.e., 0.8 mm, 1.6 mm and 3.2 mm was studied. Statistical analysis showed that the glue line treatment does not adversely affect the glue bond in plywood, while resists the termite attack considerably (Dimri et al., 1995). Khali et al. (2005) found in his study that combination of ply comprising of P. deltoides, eucalypts hybrid and Paulownia fortunei can be successfully made for overcoming the material shortage and inferior quality of plywood made from individual species. Laminated Veneer Lumber (LVL) Laminated veneer lumber (LVL), a high strength engineered material can be used as a substitute for solid wood as they retain structural properties of wood. Veneers and strips obtained from small diameter logs are glued in parallel laminates or laminated veneer lumber (LVL) which has all the properties of thick wooden planks. LVL can be manufactured in varying sizes and thicknesses, being dimensionally stable and having more uniform strength properties, it is more versatile than sawn timber. Suitability of plantation grown P. deltoides was evaluated for laminated veneer lumber (LVL) and suitability for door/window shutters (Shukla and Negi, 1998). Specific gravity of LVL is affected by pressure, pressing period and also the thickness of the veneer used. With decrease in veneer thickness, specific gravity in general increases (Shukla et al., 1996). Compressed Wood Compressed wood has improved strength and elastic properties and high resistance to wear. These properties make it suitable for use in textile industry/auxiliaries, door handles, bearing, rollers, etc. Suitability of P. deltoides and P. ciliata was evaluated for compressed wood shuttle blocks. The 128 density of poplars after compression varied within the range of 1.05 to 1.20 g/cm 3. The strength properties of the compressed wood from these two species meet the requirements specified for shuttle blocks and were comparable with imported Cornus spp., Carpinus used for making shuttle blocks (Shukla and Bhatnagar, 1989) Reconstituted Wood Reconstituted wood product developed from lignocellulosic material has highly directional properties suitable for structural purposes (Coleman, 1981). Reconstituted wood developed from lops and tops of poplar have the strength properties comparable with teak (Shukla, 1992) as reflected in Table 9. Thickness swelling somewhat higher than teak could be reduced by incorporating suitable sizing agents as in case of particle board. The product has solid edge and can be bored, shaped, moulded, nailed and screwed with machine and hand tools. It can be painted and polished with case as in case of solid wood. Table 9. Physical and mechanical properties of structural wood from poplar and compared with solid wood of poplar and teak Property Specific gravity Volumetric shrinkage AD to OD (%) Modulus of rupture (kg/cm 2) Compressive strength (kg/cm 2) Shear strength (kg/cm 2) Structural wood Poplar 0.68 4.95 1147 445 101 Solid wood Poplar Teak 0.465 0.59 11.9 4.05 780 959 381 532 90 102 Laminated Doors and Windows In solid wood the growth defects like knots are often localized and form the weakest part of the structure. The problem with poplar for its utilization for doors and windows is that it is a light timber and the presence of knots in the whole length of wood. The physical and mechanical properties of short rotation poplar wood could be considerably improved by applying the technique of laminations and simultaneous compression (Shukla, 1997; Shukla and Negi, 1998). The construction of laminated wood may be either all veneer construction or solid wood core laminated with veneer. Since poplar is not a durable timber, finished panels may be given pressure treatment with CCA preservative and dried before polishing. Plywood manufacturing units in the country using poplars can easily undertake the manufacture of laminated doors without any additional investment. Plywood Using Lignin Adhesives For reducing the cost of synthetic resin, black liquor lignin based phenolic adhesives for plywood have been developed in which the phenol is replaced with black liquor for making ENVIS adhesives. An attempt was made to develop exterior grade plywood from P. deltoides using lignin based phenolic adhesives. The result showed that 30 per cent replacement of phenol with black liquor from pine needles, the plywood meet the BWP grade and up to 50 per cent for BWR grade requirements (Singh and Singh, 1994). Fibre Board Suitability of 1 and 2-yr old P. deltoides (G3 clone) without debarking was evaluated for hardboard manufacture (Shukla et al., 1986), with a view to utilize whole tree stem. Bark/wood ratio worked out on oven dry basis for some selected stem is given in Table 10 below. The hardboards were prepared from 1 and 2-yr old plants containing 30 and 21 per cent bark respectively. One per cent emulsion was used to reduce the water absorption of the boards. Both 1 and 2-yr old P. deltoides were found suitable for hardwood manufacture. However, 2-yr old plant gave better board properties than 1-yr old. This may be due to higher percentage of bark in 1-yr old plants. The effect of mixing P. deltoides, bark and wood on the physical Table 10. Moisture content and wood/bark ratio in 1 and 2 years old P. deltoides stems Plant age (yr) Middle dia (mm) 1 2 7.26 8.30 Moisture Overall 12.5 11.0 Wood 13.8 11.2 Bark 9.5 10.2 Wood (%) Bark (%) 70 79 30 21 and mechanical properties of hardboards was also studied (Shukla, 1997). It was observed that individually poplar wood is suitable for hardboard but not the bark. However, certain quantities of bark could be mixed with wood producing satisfactory board. Bark to the extent of 20 per cent (OD) helps in improving the physical and mechanical properties of the board as compared to the boards prepared from wood alone. In standard hardboards, the bark content can be safely increased up to 50 per cent. P. ciliata without bark was evaluated for making hardboards (Shukla et al., 1985, 1986; Shukla, 1987). It was found to be a very suitable species for the purpose. Suitability of P. ciliata for hard boards was also studied by Shukla et al. (1985). Utilization of Bark A large quantity of bark constituting 10 to 20 per cent of total timber is accumulated at mill site, which is not properly utilized. The investigations carried out on utilization of bark from P. deltoides show that satisfactory plain and veneered particleboard meeting the requirements of specification are obtained (Singh et al., 1995-96). Forestry Bulletin, 12(1), 2012 Utilization for Particleboard Suitability of lops and tops of P. deltoides with and without bark as a raw material for particleboard manufacture was evaluated. The data indicated that P. deltoides wood alone and with bark (about 19 per cent) is suitable for making particleboard. Satisfactory boards meeting the requirements are made using 10 per cent phenol formaldehyde resin and 1 per cent was emulsion as sizing agent in both the cases. However, the strength properties of the board without bark are slightly better than the board with bark (Singh et al., 1995). References Badoni, S.P.; Gupta, S.; Shukla, K.S. and Sharma, S.N. 1990. A note on staining poplar (Populus deltoides) using ammonia fumigation and aqueous Terminalia alata bark extract. Journal of the Timber Development Association of India, 36(3): 20-25. Beri, R.M.; Kumar, K. and Kambo, A.S. 1979. Outside storage of wood logs II Studies on the effect of preservatives on chemical constituents and pulping quality of poplar (P. deltoides) logs during outside storage. Indian Pulp and Paper, 34(3): 3-7. Coleman, J.D. 1981. Reconstituted wood products, 1-US Patent 4232067 (7th Nov., 1980), 2- Australian Patent S1084S (9th Jan., 1981). Dev, I. and Kainth, P.S. 1989. A short note on the treatability of Acacia tortilis and Populus deltoides. In: Seminar on Social Forestry and Agroforestry, Dehradun, 19-21 December 1989. Proceedings. Dehradun, FRI. Dimri, M.P.; Shukla, K.S.; Mishra, S.C. and Kumar, S. 1995. Effect of glue line treatment on the termite resistance of plywood. Journal of the Timber Development Association of India, 41(4): 22-28. Dimri, M.P.; Rajawat, M.S. and Shukla, K.S. 1990. Plywood from Populus ciliata: Studies on pressing conditions. Indian Forester, 116(8): 631-635. Dimri, M.P.; Rajawat, M.S. and Shukla, K.S. 1993. Compression loss in plywood: Experiments on Populus ciliata. Indian Forester, 119(6): 489-497. Dobriyal, P.B.; Chauhan, K.S. and Dev, I. 2001. The durability and treatability of Populus deltoides Marsh. Indian Forester, 127(2): 207-212. Dobriyal, P.B. and Kumar, S. 1999. Treatability classification of five hardwoods based on penetration indices. Journal of the Timber Development Association of India, 45(1-2): 44-47. 129 Dubey, Y.M.; Gupta, S. and Shukla, N.K. 1997. Estimation of modulus of elasticity of Populus deltoides by vibration test method. Journal of the Timber Development Association of India, 43 (4): 5-9. Gupta, S.; Chandra, P.; Mishra, B.B. and Kishan Kumar, V.S. 2007. Gloss and ammonia fumigation studies with film forming and penetrating types of finishes on poplar surface. Journal of the Indian Academy of Wood Science, (N.S.), 4(1-2): 53-59. Indian Plywood Industries Research and Training Institute. [n.d.]. Studies on peeling, slicing, drying and gluing of Eucalyptus wood and other lesser known Indian hardwoods for the manufacture of different grades of plywood. Research Report 66. Jain, J.D.; Sanyal, S.N. and Dangwal, M.N. 1990. A note on wood poles of Populus deltoides from Haldwani (Uttar Pradesh). Journal of the Timber Development Association of India, 36(1): 25-29. Jain, V.K. and Khanduri, A.K. 2003. Interclonal variation in strength properties of Populus deltoides from Haldwani (Uttaranchal). Indian Forester, 129(9): 1069-1075. Khali, D.P.; Negi, A. and Singh, J.P. 2005. Combi plywood for general purpose (interior grade) of plantation species – Eucalyptus hybrid, Populus deltoides and Paulownia fortunei. Journal of the Timber Development Association of India, 51(1-2): 43-50. Kishan Kumar, V.S.; Gupta, S. and Sharma, C.M. 2008. Studies on vacuum press drying of Populus deltoides. Indian Forester, 134(6): 835-42. Kothiyal, V.; Khanduri, A.K. and Jain, V.K. 2005. Wood quality assessment of Populus deltoides from Haldwani (Uttaranchal). Indian Forester, 131(1): 14-24. Kumar, S. and Dobriyal, P.B. 1993. Penetration indices of hardwoods: A quantitative approach to define treatability. Wood and Fibre Science, 25(2): 192-197. Kumar, S. and Dobriyal, P.B. 1995. Treatability classification of some plantation grown wood species in India. Journal of the Timber Development Association of India, 41(1): 5-9. Page, D. and Gnanaharan, R. 1999. Influence of wood moisture on the preservative treatment of New Zealand grown poplar. Journal of Tropical Forest Products, 5(2): 154-158 Pandey, C.N. 1995. Studies on bulk flow and diffusion of moisture in Eucalyptus tereticornis and Populus deltoides for predicting drying rate. Ph.D. thesis, Forest Research Institute Deemed University, Dehradun. 130 Pandey, C.N. and Kambo, A.S. 1991. Kiln drying schedule for Populus deltoides based on diffusion theory of drying. Van Vigyan, 29(4): 208-213. Pandey, C.N. and Kambo, A.S. 1993. Sawing and seasoning of Populus deltoides by saw dry rip (SDR) process. Wood News, 3(1): 21-37. Pruthi, K.S. and Mamgain, A.K. 1994. A study on the lateral bearing strength in double and quadruple sheer joints of Populus deltoides. Indian Forester, 120(8): 101-106. Rajawat, M.S.; Shukla, K.S. and Sharma, R.C. 1989. Suitability of Indian timber for plywood: Populus ciliata (Poplar). Journal of the Timber Development Association of India, 35(1): 49-55. Rajput, S.S. 1996. Evaluation and utilisation of Populus deltoides wood – A review. Wood News, 6(3): 28-31. Rajput, S.S.; Shukla, N.K. and Khanduri, A.K. 1997. Some studies on variation of specific gravity and compressive strength of different clones of Populus deltoides. Van Vigyan, 35 (3-4): 165-171. Rao, P.V.K. 1996. Simplified process of treatments cum seasoning of slabs in pencil making. Wood News, 6(1): 11-14. Rao, P.V.K.; Jain, V.K. and Pandey, C.N. 1994. Studies on the suitability of Populus deltoides for pencil making. Wood News, 4(2): 33-37. Sharma, S.N.; Pandey, C.N. and Kambo, A.S. 1990. Residual growth strains in green sawn dimetral slabs of Populus deltoides. In: Forest Products Conference, 3 rd, Dehradun, 26-28 May 1990. Proceedings. Dehradun, FRI. Shukla, K.S. 1987. The influence of Poplus deltoides bark in wood as raw materials for hardboard. Indian Forester, 113(6): 409-417. Shukla, K.S. 1992. Reconstituted wood from poplar (Populus deltoides). Journal of the Indian Academy of Wood Science, 23(1): 17-21. Shukla, K.S. 1997. Door/window shutters from laminated poplar wood. ICFRE Brochure. Shukla, K.S. and Bhatnagar, R.C. 1989. A note on effect of compression on strength properties of Populus deltoides and Populus ciliata. Journal of the Timber Development Association of India, 35(1): 17-20. Shukla, K.S. and Negi, A. 1998. Laminated veneer lumber (LVL) from poplar for door/window shutter. ICFRE Brochure. Shukla, K.S.; Negi, A. and Shukla, L.N. 1992. Peeling characteristics of Indian timbers. Part 21. Poplar species. Van Vigyan, 31(1): 18-22. ENVIS Shukla, K.S.; Negi, A.; Singh, R. 1996. Laminated veneer lumber (LVL) from Populus deltoides. Journal of the Timber Development Association of India, 42(3): 30-35. Shukla, K.S.; Rajawat, M.S. and Shukla, L.N. 1986. Plywood from Indian timbers Populus deltoides. Journal of the Timber Development Association of India, 32(3): 13-23. Shukla, K.S.; Shah, R.S. and Bagga, J.K. 1985. Suitability of Poplus ciliata (poplar) for hard boards. Indian Forester, 3(4): 225-229. Shukla, K.S.; Sharma, Y.K. and Chandra, R. 1986. Harvesting young Populus deltoides plant for hard board manufacture. Journal of the Timber Development Association of India, 32(4): 32-37. Shukla, N.K. 1979. Poplar wood for packing cases. In: Symposium on Silviculture, Management and Utilization of Poplars, Srinagar, 15-18 October 1979. Proceedings. Simla, The Manager Government of India Press. pp. 154-156. Shukla, N.K. and Sangal, S.K. 1986. Preliminary studies on strength properties of some exotic, Indian Forester, 112(5): 459-465. Shukla, N.K. and Singh, K.R. 1995. Physical and mechanical properties of Populus deltoides, from U. P. and Haryana. Journal of the Timber Development Association of India, 41(2): 14-25. Shukla, N.K.; Dev, I.; Lal, M. and Bagga, J.K. 1996. Some studies on the effect of different preservative formulations/retentions on strength properties of Populus deltoides. Journal of the Timber Development Association of India, 42(3): 36-39. Forestry Bulletin, 12(1), 2012 Shukla, N.K.; Khanduri, A.K. and Dangwal, M.N. 2000. Physical and mechanical properties of different clones of Populus deltoides- an assessment. Indian Forester, 126(1): 31-56. Shukla, N.K.; Khanduri, A.K. and Lal, M. 1990. Physical and mechanical properties of Populus deltoides “IC” from Haldwani (UP). Van Vigyan, 28(1-2): 26-33. Shukla, N.K.; Negi, Y.S. and Guru, R.D. 1989. Physical and mechanical properties of Populus ciliata from Theog Division, Himachal Pradesh. Van Vigyan, 27(2): 102111. Shukla, N.K.; Rajput, S.S. and Lal, M. 1995-96. Strength variation in Populus deltoides- study on bottom to top variation. Journal of the Indian Academy of Wood Science, 26-27(1-2): 66-69. Shukla, N.K.; Rajput, S.S. and Singh, K.R. 1991. A note on variation of density and strength properties from pith to periphery in Populus deltoides. Journal of the Indian Academy of Wood Science, 22(1): 1-6. Singh, S.P. and Negi, A. 2001. Utilization of poplar for wood composite. Indian Forester, 127(2): 154-159. Singh, S.P. and Singh, J.P. 1994. Plywood from Populus deltoides using lignin based adhesives. Journal of the Timber Development Association of India, 25(12): 63-66. Singh, S.P.; Singh, J.P. and Rawat, S.S. 1995. Particleboard from Populus deltoides. Journal of the Timber Development Association of India, 41(4): 17-21. Singh, S.P.; Singh, J.P. and Rawat, S.S. 1995-96. Utilization of bark from Populus deltoides for particleboard. Journal of the Indian Academy of Wood Science, 26-27(1-2): 15-19. z 131 Status of Anatomy and Physical Properties of Wood in Poplars P.K. Pande Wood Anatomy Discipline, Forest Research Institute, Dehradun - 248 006 Introduction P The variability in anatomical characteristics has profound influence on properties of wood and features of interest in this connection include cell size, proportion and arrangements of different elements and specific gravity 132 oplars are among the world’s fastest growing industrial wood, which is grown in pure or mixed plantations as well as in association with agricultural crops. Poplars are also widely cultivated on the field boundaries, roads, canals, riverbanks as multipurpose tree species. Their wood is in much demand for pulp, plywood, match wood, packing cases and light constructional timber (Mathur and Sharma, 1983). In India, many species of Populus were introduced among which P. deltoides did very well and has now occupied large chunk of forests, farmland, road and canal-sides in Haryana, Jammu and Kashmir, North Bengal, Punjab, Uttarakhand and Uttar Pradesh (Chaturvedi, 1982; Dalal and Trigotra, 1983; Jha and Gupta, 1991). Wood is highly variable material and the aim of tree improvement program is to reduce these variations to obtain quality wood for the products. The variation of wood elements within a species/clone is also affected by climate and the system under which they are grown. Studies made on mature-juvenile wood characteristics have indicated that parent with high or low wood density produce progeny with juvenile wood similar to that of the parent (Zobel, 1964, 1973; Nicholls, 1967). Wood properties of mature age tree can also be predicted on the basis of wood properties evaluated at younger age (Zobel, 1965). The variability in anatomical characteristics has profound influence on properties of wood (Dadswell, 1957; Burley and Palmer, 1979). Features of interest, in this connection, include cell size, proportion and arrangements of different elements and specific gravity. The general pattern of variation in wood element dimensions is found not only within a species but also observed within a tree (Dinowoodie, 1961; Zobel, 1965; Rao and Rao, 1978; Pande et al., 1995). The important endogenous species of Populus are P. alba, P. ciliata, P. euphratica and P. nigra. They all are medium density wood. Specific gravity of these species ranges from 0. 37 (P. alba) – 0.54 (P. euphratica) (Raturi et al., 2001). Wood quality has become a major concern in the forest product industry only very recently due to the steady increase in intensively managed plantations and the move in forest management towards short rotations (Vargas-Hernandez and Adams, 1991; Zhang, 1995). Tree breeders have realized that wood quantity (volume ENVIS growth) and quality cannot be treated as independent traits and that wood quality improvement should form an integral part of tree breeding programs (Keith and Kellog, 1986; Van Buijtenen, 1986; Magnussen and Keith, 1990). A good quantum of the work was carried out world over on wood properties of poplars. Some of the studies on the different aspects of wood anatomy and physical properties of poplar’s wood were also carried out in India (Gamble, 1922; Pearson and Brown, 1932; Metcalf and Chalk, 1950; Chauhan et al., 1999, 2001; Raturi et al., 2001; Venkiah et al., 2007; Aziz and Pande, 2008, 2009, 2010; Gautam and Pande, 2008, 2009, 2010, 2011; Gautam, 2010; Pande and Dhiman, 2010, 2011; 2012; Pande, 2011, 2011a; Pande et al., 2012). Wood anatomical studies can be classified into two categories; first, structure related qualitative and second, wood variation related quantitative studies. The paper presents a detailed account of both of the dimension of the research on anatomical and physical aspects of the wood of Populus and an attempt was also made to compare it with other species. Structure Related Studies In India, anatomical studies were conducted in different Indian species of Populus by Gamble (1922), Pearson and Brown (1932), Metcalf and Chalk (1950), Raturi et al. (2001), Gautam (2010). Gamble (1922) described a small account of wood structure of P. ciliata, P. euphratica and P. alba in his classical work ‘A manual of Indian timbers’. The common features of the wood of all three species were: wood was soft, even grained, annual rings marked by smaller and fewer pores, pores small, very numerous often subdivided or in short radial multiples, rays fine to very fine, numerous and regular. The colour differentiation in wood was: grey or brownish grey in P. ciliata;, sapwood white and heartwood red coloured and black near the pith in P. euphratica whereas wood white often with red or yellowish tinge in P. alba. Metcalf and Chalk (1950) describe rays as uniseriate sometimes biseriate with less than 1 mm in height and homogeneous. Pearson and Brown (1932) and, thereafter, Raturi et al. (2001) made a complete anatomical description of these species. There not much difference was observed in wood structure of these three species. However, the colour of wood of P. euphratica was red to reddish brown with dark lines forming tortoise shell figure in flat sown board. Gautam (2010) described the structure of micro- and macro-propagated wood of L34 clone of P. deltoides as per IAWA feature list of microscopic features (IAWA, 1989) (Fig. 1). Forestry Bulletin, 12(1), 2012 Coded Description on the Basis of IAWA List Microscopic Features of P. deltoides 1. Growth ring boundaries distinct; 4. Wood semi-ringporous; 5. Wood diffuse-porous; 7. Vessels in diagonal and/ or radial pattern; 13. Simple perforation plates; 22. Intervessel pits alternate; 23. Shape of alternate pits polygonal; 24. Minute-d” 4 μm; 31. Vessel-ray pits with much reduced borders to apparently simple: pits rounded or angular; 35. Vessel-ray pits restricted to marginal rows; Mean tangential diameter of vessel lumina, 40. d” 50 μm; 61. Fibers with simple to minutely bordered pits; 66. Non-septate fibres present; 68. Fibres very thin-walled; 75. Axial parenchyma absent or extremely rare; 89. Axial parenchyma in marginal or in seemingly marginal bands; 92. Four (3-4) cells per parenchyma strand; 93. Eight (5-8) cells per parenchyma strand; 96. Rays exclusively uniseriate; 104. All ray cells procumbent; Rays per millimeter, 115. 4-12/mm (Table 1). Table 1. Coded description on the basis of IAWA List microscopic features of L-34 clone of P. deltoides Species P. deltoides Clone L34 (macro) IAWA List of microscopic coded features 1, 4, 5, 7, 13, 22, 23, 24, 31, 35, 40, 61, 66, 68, 75, 89, 92, 93, 96, 104, 115. P. deltoides L34 (micro) 1, 4, 5, 7, 13, 22, 23, 24, 31, 35, 40, 61, 66, 68, 75, 89, 92, 93, 96, 104, 115. Wood Variations Of the various wood quality parameters, specific gravity is the most widely studied. This easily assessable wood property is of key importance in forest product manufacture because it has a major effect on both yield and quality of fibrous and solid wood products (Davis, 1961; Barefoot et al., 1970; Lewark, 1979) and because it can be changed by silvicultural (Williams and Hamilton, 1961) and genetic manipulations (Zobel, 1961; Van Buijtenen, 1962). Variation in wood parameters offers possibility for selection of breeding stock with desirable wood quality. Length of cells also has a marked effect on product quality. It is generally the cell dimension next in importance to wall thickness in determining the final product value (McGraw, 1985). Although all characteristics of the cell have some effect on the quality of a manufactured product, most are minor in comparison to cell length (Zobel and Buijtenen, 1989). These include cell wall thickness, width of cell, ray characteristics, cell dimension ratios and grain characteristics, microfibril angle, etc. Other wood properties such as juvenile wood content, fiber quality, compressed wood, heartwood content, chemical properties, etc. should also be considered in future tree improvement programs (Zhang and Chui, 1996). 133 1 2 3 4 Fig. 1. 1-x, 2-r, 3-t and 4-showing fiber and vessel element in macerated material of P. deltoides L-34 clone. Within Tree Variation in Poplars Radial variation Fiber dimensions: Kaeiser (1956) reported average fiber length increased successively with the number of rings from the pith to outwards. Kaubaa et al. (1998) found similar results in the hybrids of poplars. Anatomical variations in P. deltoides were examined in 8-yr old trees of six different clones by Chauhan et al. (1999). The variation in fiber length was significant and showed an increase with the age. Radial variation with an increase from pith to outwards was reported by Chauhan et al. (2001). Variation of fiber length and fiber width for seven poplar clones was reported by Yang and Zuo (2003). The pattern of increase in fiber length and width from pith to bark was noticed. Radial variation in fiber morphology of five different poplar clones grown in Tiancchang, Anhui 134 Provenance, China, were studied for fiber length, fiber width, lumen diameter, double cell wall thickness, the ratio of fiber length to width. Result showed that from pith to outward, the fiber length, width and the ratio of fiber length to fiber width of five poplar clones all increase with the increase of growth rings; reach a maximum in a certain year and then decrease or level off (Zha et al., 2005). The radial variation in fiber length was significant for parents, individual female and male hybrid clones except Udai. Variations were also significant for fiber lumen diameter and fiber wall thickness differently in different F1 hybrids. Both significant and non-significant variations were observed for fiber length from pith to periphery with the different patterns of variations in different parents and F1 hybrid clones of P. deltoides. Further, the trend from pith to outwards was more or less increasing (Pande, 2011). Cheng ENVIS and Bensend (1979) reported fiber length increased uniformly throughout the successive growth rings from the pith in six Populus clones, they also concluded that the variation in fiber length was mainly a result of physiological and environmental factors rather than a genetic factor. Yanchuk et al. (1983) reported radial variation of fiber length in 15 genetically distinct clones of trembling aspen (P. tremuloides) from natural stands in central Alberta, Canada. Fiber length patterns of change across the radius were all very similar foremost of the clones. The increasing trend for fiber length from pith to outwards in some clones were also reported by Pande and Dhiman (2010, 2011); Pande (2011, 2011a), Pande and Dhiman (2012) and Pande et al. (2012). Comparison with other species: The studies on radial variation in different species/clones of Populus were more or less similar with the studies conducted in other tree species by different workers. Significant differences in the fiber length were observed between the core and outer wood of Paraserianthes falcatraria trees planted in Indonesia (Ishiguri et al., 2007). In radial variation of wood elements of major Korean ash species, fiber length increased from pith for 10 to 15 years and, then, stabilized (Joong and Joong, 2002). Pith to periphery variation in fiber length was reported by Purkayastha et al. (1979-80) in woods of 8-10 yrs old seedling seed raised Eucalyptus tereticornis plantations at different localities. In the same way, significant pith to periphery variations in fiber length was reported by Jorge et al. (2000) in E. globulus. Carvallo (1962), Tomazello and Variacano (1987) and Bhat (1990) in seedling seed raised progenies of different species of Eucalyptus. Fiber length increased 63 per cent from the pith to the bark in the branches of European black alder as reported by Vurdu and Bensend (1979). There was no significant difference in fiber length between lower and upper sides of branches. Anatomical characters were investigated in stems of rotan semambu (Calamus scipionum), 6-12 yrs old, from a plantation in Sarawak, Malaysia. Fiber outer- and lumen-diameter slightly increased from the centre to periphery (Roszaini, 2000). Most reports on radial pattern of variation in hardwoods and species; Acacia in particular deal with fiber length and most agree that fibres near the centre of the tree are shorter. Radial variation in the morphology of axial elements of Acacia mangium was studied by Honjo et al. (2002); radial variation in fiber length by Wu and Wang (1988), Sining (1989), Lim and Gan (2000), Susilawati et al.(2002) and by Rao and Sujatha (2004). They reported varying patterns of change in fiber length in this species. Fiber length ranged from 958 to 1,200 μm and tended to increase from the centre to the intermediate regions before decreasing slightly towards the outer regions Forestry Bulletin, 12(1), 2012 in most cases in 14-yr old Acacia mangium (Lim and Gan, 2000). Within-tree radial variation in fiber morphology was studied by Pande et al. (2008) in 12-yr old tree of Leucanea leucocephala. They observed that the variations were nonsignificant except for fiber-diameter, increased from pith to outwards. Pith to periphery variation in anatomical properties such as fiber outer diameter, fiber lumen diameter, fiber wallthickness were studied in tropical broad leaved species such as Broussonetia papyrifera, Poinciana regia, Pittosporum tetraspermu, Grevillea robusta and Tamarindus indicus by Rao et al. (1996). Fiber length increased radially from pith to bark in natural and plantation trees of the species of Hyeronima and Vochysia; ranging from 1.92 to 2.98 mm (natural) and 1.45 to 2.71 mm (plantation) for Hyeronima; and from 0.63 to 1.75 mm (natural) and 0.69 to 1.47 mm (plantation) for Vochysia. Neither species had a clearly defined juvenile wood zone. Fiber length continued to increase with distance from pith (Butterfield et al., 1993). Knigge and Koltzenburg (1965) found a rapid increase in cell length during the first 10-20 yrs in hardwoods, followed by a leveling off. This pattern was also present in poplars (Jayme et al., 1943; Scaramuzzi, 1955; Boyce and Kaiser, 1961). In contrary, Veenin et al. (2005) reported nonsignificant radial variations in fiber length in Eucalyptus camaldulensis; in Dalbergia sissoo by Pande and Singh (2005) and in Eucalyptus tereticornis by Pande and Singh (2009). The cambial age does not influenced the fiber dimension in case of clonal plantation wood of these species resulted less formation of juvenile wood as shown by nonsignificant radial variation in fiber dimensions. Vessel element’s dimensions: The increasing trend from pith to outward was reported on different clones of P. deltoides by Chauhan et al. (1999, 2001). Within-ramet radial variations in vessel element length and diameter were significant for female parent and F1 hybrids of both the sexes differently in different clones, however, non-significant for male parents. It showed differential trend of radial variation for male and female parents and F1 hybrid clones of P. deltoides for vessel element dimensions (Pande, 2011). Within-ramet radial variation in vessel element length in micro-propagated wood was significant in L-34 clone of P. deltoides, however, these variation was non-significant for macro-propagated wood (Gautam, 2010). Non-significant radial variations in vessel element dimensions were noticed in micro- and macro-propagated plantation wood of the age of 6 years with no definite trend (Pande and Dhiman, 2010). Significant variation in vessel element diameter with pith to outwards increasing trend and non-significant variation of 135 vessel element length was reported by Pande and Dhiman (2011) in some P. deltoides clones. Female (G48) clone also showed significant variation in vessel element dimensions with increasing trend from pith to outwards while male (G3) clone showed non-significant difference (Pande et al., 2012). Further, radial variations between micro- and macropropagated plantation wood were also significant for vessel element length in P. deltoides clones (Pande and Dhiman, 2010). Anatomical variations in Populus deltoides were examined in 8-yr old trees of six different clones by Chauhan et al. (1999). Significant intra-clonal variation in vessel element length, vessel element diameter and vessel frequency was observed. In general, the trend from pith to outwards was increasing for vessel dimensions as in fiber dimensions in different clones of P. deltoides. Comparison with other species: Pith to periphery variation in vessel element length was investigated in Artocarpus heterophyllus, Albizia lebbek, Casuarina equisetifolia, Glericidia spp. and Syzgium gardnerii. Results indicated that trends vary from pith to periphery depending upon the species and anatomical features (Rao et al., 2003). The length of vessel elements increased from pith outwards following a second degree curve. This dependence is the least distinct for vessel elements. In mature zone, anatomical elements are on average, 10 to 20 per cent longer than juvenile wood. With deteriorating conditions of tree growth, the length of the anatomical elements tends to increase. The most of the studies discussed above, shows increasing trend from pith to outwards for vessel element dimensions. Non-significant variations were also reported by Veenin et al. (2005) in E. camaldulensis; by Purkayastha et al. (1974) in E. tereticornis; Mamit (1986) in A. mangium; Pande and Singh (2005) in Dalbergia sissoo and Pande and Singh (2009) in E. tereticornis for vessel element dimensions. These studies mostly pertain to clonal plantations so shown less impact of juvenile wood on the wood properties. Specific gravity: Within-ramet radial variation in specific gravity were significant for female parents and nonsignificant for male parents and in most of the F1 female and male hybrids. It showed that this trait was stable in most of the hybrid clones and male parents (Pande, 2011). Non-significant radial variation in specific gravity was reported by Pande and Dhiman (2011) in parent and F1 and F2 generation clones of P. deltoides. Pande (2011a) reported significant radial variation in specific gravity of P. deltoides clones. Significant pith to periphery variations for this trait was reported by Gautam (2010) in L34 clone of P. deltoides. 136 In general, the pith to outwards trend was increasing for specific gravity. Comparison with other species: All possible patterns of wood density variations were reported in hardwoods. Medium density diffuse porous hardwoods such as the Acacia follow the general pattern of low density near the pith and then an increase, followed by a slower increase or leveling off toward the bark (Zobel and van Buijtenen, 1989). Ani and Lim (1993) studied wood density of four trees of 5-yr old A. mangium trees and also found an increase in this property in the radial direction from the centre to the outer region near the bark. Such an increasing pattern was observed in A. auriculiformis also by Kholik and Marsoem (2002). Mamit (1986) however, did not find any significant variation in wood density from pith outwards in this species while different pattern of variation in A. mangium was reported by Lim and Gan (2000) wherein density tended to increase from pith to the intermediate region before decreasing towards the bark. Within-tree, variation in the specific gravity due to direction (N, SE and SW) and pith to periphery locations were non-significant while significant due to height and its component like main bole, twig1 and twig2.in Leucanea leucocephala by Pande et al. (2008). Further, non-significant radial and vertical variations in clones of D. sissoo by Pande and Singh (2005); in E. tereticornis by Pande and Singh (2009); in E. camaldulensis by Veenin et al. (2005) and some of the hybrid clones of P. deltoides by Pande (2011). Vertical variations Fiber dimensions: Venkaiah et al. (2007) reported an increase in fiber length from base to top. Fiber length was low at the bottom and higher in mid of the tree (Kauubaa et al., 1998). Fiber length in young Populus stems, relation to clone, age, growth rate and pruning was studied by Debell et al. (2002) and reported that averaged over all disks at 1.5 m, clones differed significantly in ring width, and fiber length in contrary to the study conducted by Pande (2011) where vertical variations were non-significant for fiber length in most of the F1 male hybrids. Within-clone correlations between ring width and fiber length or between wood properties were low and generally non-significant. This pattern was also present in poplars (Jayme et al., 1943; Scaramuzzi, 1955; Boyce and Kaiser, 1961). Murphy et al. (1979) studied the selected wood properties of young Populus hybrids. Within clones, fiber length increased each year for all three clones and hybrid NE-388 had significantly greater fiber length among clones for each of the 2, 3, 4 yr. Variation of fiber length and fiber width for seven poplar clones was reported by Yang and Zuo (2003). They observed a pattern of increased fiber length ENVIS from base to top. The investigation carried out by Gautam (2010) had shown the same pattern particularly for micropropagated ramets of L-34 clone of P. deltoides and is in agreement with the studies carried by Yang and Zuo (2003). This pattern was also present in other poplars (Jayme et al., 1943; Scaramuzzi, 1955; Boyce and Kaiser, 1961). Within-ramet vertical variations in female parent (G48) were significant for fiber outer diameter, fiber lumen diameter and fiber wall thickness differently in different clones. The variation in male parent (G3) was significant for fiber length and fiber wall thickness and the pooled data was significant for all the wood traits except fiber wall thickness. Fiber length gradually increased from base to certain height and finally decreased at the top (Pande and Dhiman, 2012). The increasing trend in fiber length from bottom to top was also reported. Within-ramet vertical variations in female parent (G48) were only significant for fiber outer diameter, fiber lumen diameter and fiber wall thickness. The fiber wall thickness follow a definite trend as thick walled cells were present at the base of female parent which gradually decreased from bottom to top. The significant variations were also observed in female hybrids differently in different cases (Pande, 2011). In contrary, Inokuma et al. (1956) reported that fiber length showed a constant decrease in upward direction of Populus japanogigas. Non-significant within-ramet vertical variation in macro-propagated ramet of L-34 clone of P. deltoides for all the wood traits were reported by Gautam (2010). Further, she reported non-significant variation due to the interaction of height*direction*position. Non-significant within-ramet vertical variation was observed in G48, G3, and other F1 hybrid clones for most of the wood traits. Moreover, variations in parents and offspring for pooled data were nonsignificant for all wood traits except fiber wall thickness (Pande, 2011). Both the studies indicated that the homogeneous wood properties could be achieved at a particular height and also from the bole of individual ramet. Comparison with other species: Tajima (1967) reported that variation within a tree is often greater than that of between the trees of the same species grown under the same conditions. As stated by Larson (1967), more variability in wood characteristics exists within a single tree than among trees growing on the same site or between trees growing on different sites. McGraw (1985) for loblolly pine and Koch (1985) for hardwoods clearly illustrated some of the many within-tree patterns of wood variations. Wood varies tree to tree but also within a tree from pith outward and from the base of the tree to its top. The magnitude of within-tree differences can be very large and are important. Nonsignificant vertical variation in fiber length while significant Forestry Bulletin, 12(1), 2012 variation in fiber diameter and lumen diameter in 28-yr old Daniellia oliveria was reported by Idu and Ijomah (2000). Yang and Zuo (2003) reported a pattern of increased fiber length from base to top. In contrary, non-significant vertical variation in fiber dimensions in clones of D. sissoo by Pande and Singh (2005); in E. tereticornis Pande and Singh (2009); in E. camaldulensis by Veenin et al. (2005); in 12-yr old tree of L. leucocephala by Pande et al. (2008) and some of the hybrid clones of P. deltoides by Pande (2011). Vessel element dimensions: Significant axial differences in vessel element length of some clones of P. deltoides was reported by Chauhan et al. (2001) with irregularly increasing trend. Gautam (2010) reported significant axial variation in vessel element length while non-significant variation for vessel element diameter in L-34 clone of P. deltoides with irregular trend for vessel element length while increasing bottom to top trend for vessel element diameter. Nonsignificant axial variation was reported in most of the F1 hybrids and parents of Populus deltoides with irregular trend by Pande (2011). The more or less similar results were also obtained in micro- and macro-propagated plantation wood of Populus deltoides (Pande and Dhiman, 2010). Significant variations in vessel element length in G48 clone whereas nonsignificant variations in vessel element dimensions in G48 and G3 (vessel element diameter) of P. deltoides with increasing trend from bottom to top were reported by Pande et al. (2012). The above studies indicated that pattern in axial variations in vessel element length is variable from clone to clone in P. deltoids, however, general bottom to top trend was increasing. Comparison with other species: Dimensional variation was investigated in vessel characters along vertical and horizontal axes of a 40-yr old tree of Afzelia africana in Gerei forest, Nigeria. Mean dimensional values were: vessel element diameter 233.46 μm and F/V length ratio 2.25. Other traits analyzed showed considerable variation but were not significantly related to distance along either axis (Idu and Ijomah, 1996). Variation in dimensions from stem base to the top in trees of ‘aroeira’ Myracrodruon urundeuva was reported (Florsheim et al., 1999). Discs were removed from each tree at the base, breast height and 50 per cent and 100 per cent of commercial height. Samples were taken from each disc at 0 per cent, 50 per cent and 100 per cent of the radius. In the longitudinal direction, the lowest value of vessel element length and diameter were found at the base, while the highest were found at 50 per cent of commercial height. The pattern of axial variation of vessel 137 dimensions in Populus is more or less similar as in the other tree species. In contrary, non-significant vertical variations in vessel element dimensions in clones of D. sissoo by Pande and Singh (2005); in E. tereticornis by Pande and Singh (2009); in E. camaldulensis by Veenin et al. (2005); in 12-yr old tree of L. leucocephala by Pande et al. (2008) and some of the hybrid clones of P. deltoides by Pande (2011). Specific gravity: Significant differences with decreasing trend bottom to top in specific gravity of some clones of P. deltoides was reported by Chauhan et al. (2001). Gautam (2010) also reported significant axial variations in specific gravity in L-34 clone of P. deltoides with increasing trend from bottom to top. Significant axial variation was reported in most of the hybrids of P. deltoides by Pande (2011). Non-significant axial variation in specific gravity was obtained in micro- and macropropagated plantation wood of P. deltoides (Pande and Dhiman, 2010) while significant variation in specific gravity in G48 and G3 clones of P. deltoides with increasing trend from bottom to top was reported by Pande et al. (2012). Radial and inter-progeny variations in the dimensions of the wood elements and specific gravity of 21 half sib progenies of P. deltoides was reported by Pande and Dhiman (2012). Significant radial variation was reported for specific gravity. In general, it was concluded that axial variations in specific gravity in different clones was shown different patterns however the trend from bottom to top was increasing. Intra and Inter-Clonal Variations Intra- and inter-clonal variations in wood traits in the genus Populus were studied by many a worker (Phelps et al., 1982; Kauba et al., 1998; Chauhan et al., 1999; Chauhan et al., 2001; Aziz and Pande, 2008, 2009, 2010; Gautam and Pande, 2008, 2009, 2010;; Gautam, 2010; Pande, 2011, 2011a; Pande and Dhiman, 2011, 2012). Fiber dimensions: Fiber length in young Populus stems, relation to clone, age, growth rate and pruning was studied by Debell et al. (2002). They found variations among the clones. Murphy et al. (1979) studied the selected wood properties of young Populus hybrids and observed interclonal variation. Variation of fiber length and fiber width for seven poplar clones was reported by Yang and Zuo (2003) and found significant variations among the clones for fiber length. Clone to clone variations in some parent and hybrid clones for wood traits were also reported by (Pande 2011, 2011a; Pande and Dhiman, 2011). Further, inter-clonal variations were also recorded in the hybrids of the different parental combinations (Pande, 2011). Anatomical properties 138 of selected Populus clones under intensive culture were studied (Cheng and Bensend, 1979). The within-tree and among-clone variations were evaluated for anatomical properties and fiber quality, particularly the amount of tension wood. Significant intra- and inter-clonal differences in fiber dimensions of some clones of P. deltoides was reported by Chauhan et al. (1999, 2001). Inter-clonal variation was reported by Venkaiah et al. (2007). The longest fibers were found in the clone ‘IC’ (1.236 mm), closely followed by ‘A-238’ (1.222 mm) and shortest fibers in ‘6-17’ (0.952 mm). Gautam (2010) also reported significant intra-clonal variations and variations due to different sites in fiber dimensions in L-34 clone of P. deltoides. Significant intra- and inter-clonal variations were reported in most of the hybrids of P. deltoides by Pande (2011). Significant intra- and inter-clonal variations in fiber dimensions were obtained in micro- and macro-propagated plantation wood of Populus deltoides (Pande and Dhiman, 2010) and also in G3 and G48 clones of P. deltoides by Pande et al. (2012). Inter-progeny variation in 21 half sib families of P. deltoides was reported by Pande and Dhiman (2012). Vessel element dimensions: Anatomical properties of selected Populus clones under intensive culture were studied and inter-clonal variation was reported (Cheng and Bensend, 1979). Significant intra- and inter-clonal differences in vessel element dimensions of some clones of P. deltoides were reported by Chauhan et al. (1999, 2001). Gautam (2010) also reported significant intra-clonal variations and variations due to different sites in vessel element dimensions in L-34 clone of P. deltoides. Significant intra- and inter-clonal variations were reported in most of the F1 hybrid clones of P. deltoides by Pande (2011). Significant intra- and inter-clonal variations in vessel element dimensions were obtained in micro- and macro-propagated plantation wood of P. deltoides (Pande and Dhiman, 2010) and also in G48 and G3 clones of P. deltoides were reported (Pande et al., 2012). Specific gravity: Wood density in 9-yr old Populus clones were studied in relation to clone age, growth rate and pruning and inter-clonal variation was noticed (Debell et al., 2002). Song et al. (1997) noticed significant difference in wood density of trembling aspen among four locations in China. Clone × environment interaction was significant. Natural variation in P. tremuloides was reported. The variation within clone was environmentally caused. The variation between clones is caused by differences in environment as well as in genetic constitution. Diameter, volume and specific gravity showed wide differences in one and the same clone as compared to between-clone differences, whereas fiber length ENVIS showed less pronounced within-clone variation (Van Buijtenen et al., 1962). Variation in P. deltoides was examined in 8-yr old trees of six different clones. Significant inter- clonal variation was observed in specific gravity, fiber length, vessel element length, fiber diameter, lumen diameter, vessel frequency and vessel diameter. (Chauhan et al., 1999). Interclonal variation in P. deltoides in specific gravity and wood parameters of 18 clones in 10-yr old trees was observed. The inter-clonal differences were significant in anatomical parameters and specific gravity while within clones showed no significant effect (Chauhan et al., 2001). Gautam (2010) reported significant intra-clonal variation in specific gravity in L-34 clone of P. deltoides. Significant intra- and inter-clonal variations were reported in most of the F1 hybrid clones of P. deltoides (Pande, 2011). Significant intra- and inter-clonal variations in specific gravity were obtained in micro- and macro-propagated plantation wood of P. deltoides (Pande and Dhiman, 2010) and also in G48 and G3 clones of P. deltoides (Pande et al., 2012). Inter-progeny variation was reported in 21 half sib progenies of P. deltoides (Pande and Dhiman, 2012). Genetic variation in wood properties among and within three provenances of balsam poplar was investigated. Thirty clones from each provenance, with four ramets per clone were measured for growth characteristics, and specimen disks were cut at tree base. The result showed significant difference among the three provenances in growth rate and cell length. Growth rate, relative density and fiber length as dependent variable showed differences between the southern and northern provenance with the local source in an intermediate position. Both genetic and environmental variances for a certain trait differed from provenance to provenance (Ivkovich, 1996). Wood characteristics of twenty poplar clones grown under short rotation intensive culture in Himalchal Pradesh at the end of 9th year was studied by Venkaiah et al. (2007). Inter-clonal variation was significant for specific gravity. Clone ‘5-18’ (0.427) showed maximum specific gravity and minimum by clone ‘C-181’ (0.333). Variation within tree of wood anatomical properties and basic density of I-214 poplar in Beijing and their relationship modeling equations was reported by (Jiang et al., 2003). This includes the length and width, fiber wall thickness, tissue ratio, fiber wall ratio, basic density and width of growth rings. Different studies on intra- and inter-clonal variations in different clones of P. deltoides indicated that most of the clones were different from each other for specific gravity. Comparison with other species: Significant differences among the different clones of different species in average fiber-length were also reported by many workers (Murphey Forestry Bulletin, 12(1), 2012 et al., 1979; Phelps et al., 1982; Chauhan et al,. 1999; Chauhan et al., 2001; Rao et al., 2002). Einspahar et al. (1963); Kennedy (1970); Cheng and Bensend (1979) and Peszlen (1994) reported that fiber-length was under genetic control. Such types of results were also obtained by Pande and Singh (2005) for D. sissoo. Clone to clone variation was also reported in vessel element and fiber dimensions and specific gravity in Tectona grandis for wood properties (Rao et al., 2003); in D. sissoo by Pande and Singh (2005) and in E. tereticornis by Pande and Singh (2009). The view is also in consonance with Chauhan et al. (1999, 2001) and Pande (2011, 2011a). Wood Anatomical Properties and Density The dimensions of wood elements and specific gravity in different species and clones of Populus reported in Indian literature are given in Table 2. The average fiber length for different species/ clones of Populus ranged from 550 (P. euphratica) to 1,700 μm (P. ciliata); fiber diameter ranged from 21.91 (Micro L-34) to 34 μm (P. ciliata); wall thickness from 2.69 to 5.50 μm (G3) and specific gravity ranged from 0.326 (66, M, F1) to 0.518 (S7C3). Average vessel element length ranged from 108.56 (14) to 935 μm (P. ciliata) and vessel element diameter from 58.30 (L12/82) to 150 μm (P. euphratica). Table 3 shows the wood properties of some commercially grown clones of P. deltoides grown in India. W-34, Bahar and G48 clone showed higher fiber length, specific gravity; G48, G3, Kranti and Udai showed higher fiber diameter and wall thickness and vessel element dimensions. In general, fiber length was higher in female while wall thickness in male clones. Specific gravity showed mixed trend. Variation in Proportion of Tissues Inter-ramet and variation due to site in proportion of tissue and vessel frequency (mm-2) was non-significant. Radial variation was non-significant for fiber (per cent), vessel (per cent) and parenchyma (per cent) whereas significant for ray (per cent). Further, the variations in proportion of tissue between macro- and micro-propagated plantation’s wood and within and inter-ramet variations were non-significant for all the wood traits in L-34 clone of P. deltoides (Gautam, 2010). Inter-clonal significant variation in fiber, vessel and parenchyma percentage was reported in parents and F1 female hybrids. Intra – clonal variation was significant for fiber (per cent) only while radial variation was for vessel frequency (Pande, 2011). Correlation analysis indicated that fiber (per cent) was significantly negatively correlated with vessel (per cent), parenchyma (per cent) and ray (per cent) while significantly positively correlated with vessel element diameter and specific 139 Table 2. Wood element’s dimensions (μm) and specific gravity FL FD WT VL VD SG Authority 1048.2 (G3) 1229.3 (W-39) 1023 (G-3)-1096 (112910) 23.3 (Cp82-5-1)-28.3 (G3) 3.9 (W-39)-5.0 (G3) 531.9 (Bahar)-597.8 (W/A 39) 96.1 (G48)-109.5 (W22) 0.333 (Kranti)- 0. 423 (G48) Pande, (2011a) 23.4 (S7C3)-24.8 4.39 (S7C3) -3.8 (112910) - - (G3) 0.383-(112910) 0.405-(S7C3) 0.441 Goyal et al. (2001) 968 (104)-162 (G48) (104) 22.11-28.1(G3) 3.53(66)-5.04(G3) 532 (W/A 49) -108.56 (14) 96.11 (G48)-108.56 (102) (66, M, F1) 0.326-(G48, F, P) 0.423 Pande et al. (2011) (G3) 1075.14-(G48) 1244.07 (G3) 23.19 - (G48) 26.68 (G3) 4.08-(G48) 3.09 (G3) 546.04- (G48) 590.32 99.25 (G3)-105.86 (G48) 0.41 (G3)-0.39 (G48) Pande et al. (2012) Macro 960.29 (L-34)1010.29 (S7C15 23.7 (L-34)-22.55 (S7C15) 3.56 (L-34)-4.15 (S7C15) (L34) 519.31-(G3) 546.04- 554.07 (S7C15) 0.38 (L-34)-0.38 (S7C15) Micro 996.41 (L34)954.2 (S7C1) 1100 (S7C15)1473.50 (L71/84) 957(G3)-1122 (St121) 1196 (D100) 1.236 (IC) 21.91 (L-34)-23.44 (S7C) 23.0 (L52/8)-28.0 (G3) 22.0 (St63)-26.0 (G48) - 3.55 (L-34)-4.00 (G3) 3.7 (L52/8)-5.50 (G3) 3.83 (S7C13)-5.06 (G3) - 544.02 (L-34)- 576.42 (G3) 598.00 (S7C20)-695.50 (L75/84) L188/84) 416 (G3)-552 (St-121) - 100.10 (L34)-91.7 (S7C15) 90.94 (L34)(G3)102.98 (G3) 58.3(L12/82)85.25(S7C20) 59.6(S7C13)71.3(S7C3) - P. euphratia 550-1620 P. ciliata 635-1700 (L-34) 1083.82-1129.70 27-30 3-4 425-600 135-150 0.47 30-34 3-4 250-935 100-120 0.32 22.58-23.66 2.692.78 579.81- 603.52 97.43-108.08 0.336-0.401 0.379 (L-34)-0.345 (G3) 0.34 (D121)-0.44 (L290/84) 0.404 (G3)0.518 (S7C3) 0.333 (C181) 0.427)(5-18) Pande & Dhiman. (2010) Chauhan et al. (2001) Chauhan et al. (1999) Venkaiah et al. (2007) Pearson Brown (1932) Pearson Brown (1932) Gautam (2010) Table 3. Wood and growth traits of some commercial clones of P. deltoides F FL±SD (µm) 1140.0±161.00 FD±SD (µm) 25.67±4.32 WT±SD (µm) 4.47±0.92 VL±SD (µm) 560.22±125.78 VD±SD (µm) 103.11±26.33 Wood density (g/cm3) 0.368 F 1161.8±169.78 25.78±4.41 4.48±1.07 F 1048.8±145.78 27.89±4.30 4.77±0.92 552.56±113.89 96.11±20.78 0.423 560.22±101.22 104.44±19.89 0.333 W/A 49 F 1142.3±116.44 23.67±2.29 W-39 F 1229.3±131.1 25.3±2.4 3.77±0.34 532.78±84.56 99.67±15.67 0.406 3.9±0.42 572.3±88.5 106.7 ±18.6 Bahar F 1190.0 ±161.1 0.420 24.8±3.4 3.9±0.70 531±107.8 96±18.7 G3 M 0.420 1048.2±201.11 28.11±5.38 5.04±1.36 559.44±142.33 108.44±31.22 0.366 Cp82-5-1 W 22 M M 1049.0±160.22 1136.3±133.7 23.33±4.28 26.2±1.2 4.17±1.11 4.3±8.9 558.22±115.67 558.0±99.5 105.11±29.56 558.0±19.9 0.350 0.367 Udai M 1119.16±29.7 25.98±0.6 4.62±0.16 660.05±34.2 107.89±3.60 0.380 Clone Sex S7C8 G48 Kranti Source: Pande and Dhiman (2011) gravity. Vessel (per cent) was significantly negatively correlated with ray (per cent). Ray (per cent) was significantly negatively correlated with vessel element diameter and significantly positively correlated with specific gravity. Vessel frequency was significantly negatively correlated with fiber length, fiber diameter and vessel element diameter (Gautam, 2010). It reflected that the proportion of different secondary xylem elements were showed their relationship with each other in L-34 P. deltoides clone. Comparison with other species: The higher values of vessel (per cent), ray (per cent) and parenchyma (per cent) and lower 140 values of fiber percentage has been reported by Marsoem et al. (2002) in A. auriculiformis and by Sahri et al. (1993) and Rao and Sujatha (2004) in A. mangium may be attributed to the juvenile nature of the materials studied. Since the materials studied were from the juvenile phase of growth (about 41/2yr old) there might have been a necessity for having more conducting (vessels) and transportation (axial and ray parenchyma cells) tissues than those rendering mechanical strength (fibres). As age advances, the percentage of fibres is expected to increase coinciding with a reduction in proportion of the other cell types. In contrary, Pande, 2011 ENVIS and Gautam (2010) observed higher percentage of fibers as compared to vessel in parent and F1 hybrid clones and L-34 of P. deltoides, respectively. It showed properties of mature wood in the species. Ramirez et al. (2009) reported wide range of variation in Eucalyptus globules clones for vessel frequency, vessel area and vessel coverage among the clones. From pith to bark, mean vessel area and vessel coverage increased gradually, whereas the vessel frequency decreased. Vessel frequency decreased with the radius in E. pilularis (Bamber and Curtin, 1974); in E. nitens (McKimm and Ilic, 1987) and in E. globules (Carvallo, 1962; Hudson et al., 1998). Decreasing trend from pith to periphery for vessel frequency was also reported in E. regnans (Dadswell, 1958), E. camaldulensis (Chudnoff and Tischler, 1963), E. grandis (Bamber and Humphreys, 1963), and E. viminalis (Nicholls and Phillips, 1970). In one tree of E. camaldulensis the fiber, vessel and parenchyma volume (per cent) varied between 47-62, 13-19, 24-37 and in an another tree it varied between 39-40, 11-17, 44-49, respectively (Chudnoff and Tischler, 1963). In E. deglupta the fiber and vertical parenchyma, vessel and rays (per cent) were 63.5, 27.9 and 10.5 (Davidson, 1972). Radial variation in proportion of cell type in Paraserianthes falcataria was studied by Ishiguri et al. (2009). They observed that vessel (per cent) and axial parenchyma (per cent) showed almost constant values up to 10 cm from pith and then increased toward the bark. On the other hand, no consistent radial pattern was recognized in the ray parenchyma (per cent). The radial variation in vessel morphology and tissue proportions in 8-9 yrs old plantation-grown A. mangium raised at the Chandrapura range, Sirsi, Karnataka, India was studied (Kumar et al., 2006). Significant radial variation from pith outwards was observed in respect of vessel (per cent), parenchyma (per cent) and ray (per cent) only in P. deltoides L 34 clone (Gautam, 2010). Correlation studies indicated that fiber, vessel morphology and tissue proportions were independent of basic density (Rao and Sujatha, 2004). Significant pith to periphery variation in vessel frequency, vessel diameter, percentage of solitary vessel was reported in plantation grown Tecomella undulate by Rao et al. (2003a). Pith to periphery variation in vessel frequency, vessel element diameter, vessel element length and their proportions were investigated in Artocarpus heterophyllus, Albizia lebbek, Casuarina equisetifolia, Glericidia spp. and Syzgium gardnerii. Results indicated that trends vary from pith to periphery depending upon the species and anatomical features (Rao et al., 2003). In general, the trend of the proportion of different tissues for pith to outwards in P. deltoides clones was increasing, which also agrees with the results of the Pande (2011). Forestry Bulletin, 12(1), 2012 Variation in Micro Fibril Angle (MFA) Intra-clonal variation in MFA was significant in L-34 clone (Gautam, 2010). Inter-clonal variation was significant in MFA while intra-clonal and within ramet variations were non-significant in parents and F1 hybrids of P. deltoides (Pande, 2011). Intra-ramet and multiplication variations in MFA were non-significant while inter-ramet variation was significant. Variations due to techniques (macro- vs. micropropagated wood), intra- and inter-ramet variations in MFA were non-significant (Gautam, 2010). Pith to bark variations in Populus clones showed MFA ranging from 280 (pith) to 80 (bark) in 11-yr old trees at breast height (Fang et al., 2006). In hardwoods, there are also differences in among tree variations in MFA. Evans et al. (2000) reported in E. nitens MFA declines from 200 at the pith to 140 at the bark but unlike conifers, the angles are much lower near pith typically 15-20o, this report was in disagreement with the results of Pande (2011). The most notable difference is that among tree variations at the pith is only slightly greater then at then the bark in 15-yr old E. nitens (Evans et al., 2000). MFA in E. grandis clones, Lima et al. (2004) found almost no change from pith to bark. However, the trees in their study were only 8-yr old. Differences in MFA among trees are generally more apparent in the juvenile wood. However, by the age of 15 yrs and beyond, the trees generally have comparable low MFA values (Donaldson, 1992). In contrary to the study of Lima et al. (2004), Pande (2011) showed nonsignificant pith to outwards variation in MFA with increasing trend. It may be explained that lower age of trees of study (Pande, 2011) showed non-stability of MFA in early phase of tree growth showing the impact of juvenile wood. Vainio et al. (2002) have shown significant variation in MFA between provenances in Picea sitchensis, with trees from California and Queen Charlotte Islands provenance having higher MFA then trees of Washington and Oregon provenances. In spruce fiber, the pattern and extent of variation were investigated (Gilani et al., 2006) and the results are in agreement of the idea that the orientation of MFA is not uniform along the radial wall of earlywood fibers. Their MFA was found highly variable within the radial wall of earlywood fibers, especially in the vicinity of the bordered pits. On the other hand, in tangential wall of earlywood and in the whole latewood fibers MFA was approximately uniform. In conifers, MFA varies from pith to bark, with the highest angles occurring in the first five growth rings from pith at the base of the tree (Phillips, 1941; Donaldson, 1992; Xu Bin et al., 2004; Jordan et al., 2005; Zhang et al., 2007). 141 MFA in L-34 clone was significantly negatively correlated with vessel element diameter whereas significantly positively correlated with specific gravity (Gautam, 2010). Tracheid length and micro-fibril angle were linearly, negatively and significantly correlated with each other within a tree in slash pine (P. elliottii), although there was no significant correlation between tracheid length and MFA among stands on the same location (Xu Youming et al., 1999). The result of study conducted by Pande (2011) was also in agreement with the later statement. Pith to bark variations Populus clones showed MFA ranging from 280 (pith) to 80 (bark) in 11-yr old trees at breast height (Fang et al., 2006). The results of Gautam (2010) in P. deltoides was disagreement with the report for Douglas-fir trees, where MFA decreased with age from over 30Ú to about age 30 and tracheid length was highly correlated with MFA (Erickson and Tsuneo Arima, 1974), whereas study of Gautam (2010) showed non-linear relationship. McMillan (1973) described MFA of loblolly pine wood as related to specific gravity, growth rate and distance from pith. It was observed that MFA were greater for early-wood (avg.33.4Ú) than for the latewood tracheids (avg.29.6Ú). For early-wood, MFA did not differ between growth rates when the specific gravity was low (avg.33.3Ú) and the specific gravity was high, wood of fast growth had a higher MFA (avg.35.1Ú) than the wood of slow growth (avg.32.0Ú). No differences were detected between core, middle, and outer wood. In latewood trachieds, MFA were greater in core wood (avg. 28.0Ú) than in middle or outer wood (avg.26.3Ú). For whole wood, MFA averaged 30.7Ú and was greater in core wood (avg.32. 2Ú) than in middle or outer wood (avg.29.9Ú). Sex Related Wood Anatomical Variations Wood anatomical characters and specific gravity in relation to sex; inheritance from parents to the F1 offspring of P. deltoides was reported by Aziz and Pande (2008, 2009). Fiber length was highest in female offspring (Bahar) followed by male offspring, female (G48) and male parent (G3). Vessel element diameter and specific gravity were higher in male group followed by female group. Offsprings also showed hybrid vigor. Pande and Dhiman (2011) reported that fiber length and specific gravity were significantly higher in female, while wall thickness and vessel element length were higher in male clones. In another study, Pande et al. (2012) reported intraand inter-ramet, and inter-clonal variation in dimensions of wood elements and specific gravity of six-yr old P. deltoides based on sexual dimorphism of a female (G48) and male clone (G3). Both of the clones differ significantly for fiber length and diameter, wall thickness, vessel element length and 142 diameter, and specific gravity. Female (G48) clone showed higher fiber and vessel element dimensions but lower specific gravity than G3 clone, suggesting better fiber dimensions for G48 and specific gravity for G3. It showed female dominance on wood anatomical properties (Table 4). Table 4. Clone mean wood element dimensions (μm) and specific gravity of G48 and G3 Wood trait Clone Fiber length (Unit) G3 G48 G3 G48 G3 G48 G3 G48 G3 G48 G3 G48 Fiber diameter (Unit) Wall thickness (Unit) Vessel element length (Unit) Vessel element diameter (Unit) Specific gravity (Unit) Mean±S.E. 1075.14± 11.97 1244.07±11.97 23.19±0.47 26.68±0.47 4.08±0.16 3.09±0.16 546.04±4.45 590.32±4.45 99.25±0.76 105.86±0.76 0.41±0.004 0.39±0.004 95% Confidence interval Lower bound Upper bound 1051.55 1098.73 1220.47 1267.66 22.27 24.12 25.75 27.60 3.77 4.38 2.79 3.40 537.26 554.81 581.54 599.09 97.76 100.74 104.37 107.35 0.40 0.42 0.38 0.40 Source: Pande and Dhiman, 2012 Variations in Micro- and Macro-Propagated Plantations Intra- and inter-ramet variation in wood traits of micropropagated L-34 clone plantation of P. deltoides was studied (Gautam et al., 2008). Intra- and inter-ramet variation in fiber diameter and vessel diameter was significant. Non-significant differences in most of the wood element’s dimensions for height, direction and location showed homogeneous wood properties within the macro-propagated ramet of L-34 clone of P. deltoides. Significant intra-clonal variations for vessel element diameter and fiber diameter showed that these characters were not controlled in micro-propagated plantation wood of L-34 clone, while, important characters like fiber length, wall thickness and specific gravity were well controlled in L-34 clone. The site variations also affected the wood properties of the micro-propagated plantation wood. The dimensions of wood elements and standard deviation are set in Table 5. Intra- and inter-clonal variations in fiber length, fiber diameter, wall thickness, vessel element length, vessel element diameter and specific gravity in the ramets of L34, G3 and S7C15 clones of P. deltoides at the age of 6-yr old produced from planting material grown by macro- and micro-propagation techniques were reported by Pande and Dhiman (2010). Intra-ramet variations were non-significant for all the characters except specific gravity for height in L-34 for macro and specific gravity and vessel element diameter for radial locations for micro, and fiber length for G3 (micro) for height, and specific gravity for radial location and fiber length for height for S7C15 clone for both the techniques. The variations were significant for vessel element length and specific gravity between the ENVIS Table 5. Mean ± SD for wood element’s dimensions (μm) and specific gravity Parameter/Clone L34 Macro Micro Mean Macro Micro S7C15 Macro Micro FD WT VL VD SG 24 3.56 519 100 0.384 SD 80 1 0.27 32.0 6.1 0.039 Mean 996 22 3.55 544 91 0.379 70 1 0.23 46 6 0.040 1075 23 4.08 546 99 0.411 0.039 SD G3 FL 960 Mean SD 112 1 2.27 42 9 Mean 1079 24 4.00 576 103 0.345 SD 124 2 0.42 33 11 0.030 % CV 12 7 11 6 11 9 Mean 1010 23 4.15 554 92 0.383 SD 129 1 0.30 47 6 0.036 Mean 954 23 3.73 539 97 0.369 SD 47 1 0.13 19 8 0.035 FL=fiber length, FD=fiber diameter, WT=wall thickness, VL=vessel element length, VD=vessel element diameter, SG=specific gravity and SD=standard deviation. Source: Pande and Dhiman (2010). wood produced from planting stocks grown by two techniques. Intra-clonal variations were significant for fiber length, fiber diameter and vessel element length. In general wood element’s dimensions and specific gravity increased from bottom to top and pith to periphery radial locations. G3 clone was different from the L34 and S7C15 clone for the wood traits. The three different clones of P. deltoides showed variability in wood anatomical properties and specific gravity in the woods grown from macro- and micro-propagated planting stock. So, the plantation raised by two techniques could not produce similar type of wood even from the same clone. G3 clone was the exception as it did not show variation in wood traits for two techniques. Intra-clonal variations in all the three clones of P. deltoides indicated that wood traits were not stable within the population of same clone grown by either method (Pande and Dhiman, 2010). Inheritance Patterns and Heritability The inheritance of fiber characteristics in hardwoods was reviewed by Zobel (1965) but there has been a great deal of information developed since then, especially for the genera Eucalyptus and Populus. Evidence for hardwood is somewhat scant, but those studies reported indicate that there is a moderate genetic control of cell length. A striking example of a large increase in fiber length was that obtained through polyploidy in Populus spp., where van Buijtenen et al. (1958) found fiber length to be increased by 21-26 per cent. Genetic gain for all the wood and growth traits was positive Forestry Bulletin, 12(1), 2012 particularly for most important wood trait like specific gravity, wall thickness (Pande, 2011). Inheritance patterns of wood traits were reported by Aziz and Pande (2008) in parents and F1 hybrid clones of P. deltoides. The variations were significant for wall thickness and were found to be highest in offspring than parents showing hybrid vigor. Characters like fiber length, wall thickness and vessel element length were higher in the offsprings followed by parents whereas fiber diameter, vessel element diameter, specific gravity and Runkel ratio were higher in parents followed by the offspring. The inheritance patterns of different wood traits in different three crosses (G48*G3, G48*St-63 and C7S8*G3) of P. deltoides were reported by Pande (2011). The combination of all the wood traits indicated that wood anatomical properties and specific gravity inherited male parent to male offsprings while female parent to female offsprings. The exception was CC01 (male clone) which clustered with female parent (G48) and indicated that there might be possibility of inheritance of wood traits from female parent to male offspring. Further, in the cross of G48*St-63, the pattern of inheritance from both the parents to female hybrid clones only. It may be due to the divergence of male parent, viz. St-63 from all the F1 offsprings and female parent. The inheritance pattern in C7S8*G3 cross was male parent to male and female offsprings and female parent to female offsprings only. Hence, it indicated that wood traits mostly inherited in P. deltoides from same parental sex to same offspring sex. Further, enhancement in the dimensions of wood traits in F1 male offsprings showed the influence of hybrid vigor. On the basis of different crosses, following pattern of inheritance for wood traits were reported (Pande, 2011): 1. Female parent to female offsprings and male parent to male offsprings. 2. Female parent to both male and female offsprings and male parent to both male and female offsprings. 3. Male parents to female offsprings and female parent to male offsprings. 4. The traits are higher in the offsprings than of the parents showing hybrid vigor. Heritability, Genetic Advancement and Genetic Gain for Growth and Wood Traits The genetic parameters like total genetic variations and genetic control for a particular trait are important tools to predict the amount of gain to be expected from the genetic material (Foster and Shaw, 1988; Kumar, 2007). The genotypic and phenotypic coefficient of variation for all the wood traits indicated the adequate amount of genotypic variations. The higher genotypic and phenotypic coefficient of variations 143 were showed by wall thickness and vessel element dimensions. The higher values of phenotypic coefficient of variation as compared to genotypic coefficient of variations for fiber length and vessel element length indicated that these characters were also influenced by the other factors. The fiber wall thickness and specific gravity are the characters which are more in genetic control (Pande, 2011). Heritability expresses the degree to which a character is influenced by genes as compared to environment. Broad sense heritability (h2) was 0.54 for fiber length, 0.68 for fiber diameter, 0.85 fiber wall thickness, 0.64 for vessel element length, 0.84 for vessel element diameter and 0.60 for specific gravity (Pande, 2011). The heritability values reported for different species of Populus and their clones were in the range of 0.56 - 0.70 (Farmer and Wilcox, 1966, 1968; Reck, 1974; Nepveu et al., 1978) for specific gravity. The heritability values for fiber length for P. deltoides was reported as 0.36 (Farmer and Wilcox, 1968); for Populus polyploids was 0.50 (Einspahr et al., 1963) and for P. trichocarpa was 0.71 (Reck, 1974). The values of heritability reported by Pande (2011) were well within the range of the above reported values for fiber length and specific gravity. Though, evidences on heritability for hardwoods are somewhat scant, yet those studies indicate that there is moderate genetic control of cell length (Zobel and Buijtenen, 1989). Heritability values express the proportion of variation in the clones that is attributed the genetic differences among the clones, genetic advance indicates average improvement in the offspring over the parents. In the study of Pande (2011), genetic advance was higher for vessel element length (82.13) followed by fiber length (73.88), vessel element diameter (31.87), fiber diameter (2.59), wall thickness (0.95) and lowest for specific gravity (0.04). Genetic gain (per cent) was higher for vessel element diameter (28.39) followed by wall thickness (25.82), vessel element length (14.26), fiber diameter (10.84), specific gravity (8.99) and fiber length (6.45) for the wood traits. The narrow sense heritability was also calculated for the studied traits from parent -offspring regression. The trend between broad sense and narrow sense heritability was more or less similar (Pande, 2011). It is important to calculate so that additive genetic variance associated with individual trait component can be calculated. In case of full sib families are measured, and progeny value were regressed on the average value of two parents (midparent value), then equals to narrow sense heritability (Zobel and Tilbert, 1984). Most of the work on specific gravity and fiber dimensions of hardwood has concentrated on the eucalypts and poplars. Although some of the studies were not as 144 rigorous as could be desired, it appears that wood specific gravity in these two genera is inherited as strongly or stronger than in conifers. This seems to be true for sycamore (Platanus) and P. deltoides (Pande, 2011). The inheritance of specific gravity in Swietenia and teak (Tectona) is somewhat weaker, but results are based on fewer studies. However, in the study (Pande, 2011), higher values of heritability of P. deltoides indicated that heritability studies were also important for wood traits like fiber dimensions and specific gravity for breeding program. There is a current upsurge of interest in inheritance of wood properties in hardwoods, and soon many results will be available for trees beyond the juvenile stage (Zobel and Buijtenen, 1989). Higher heritability values and positive genetic gain for wood traits for P. deltoides showed that there was a great possibility of the improvement of the species for wood and growth traits through different and defined breeding programs. Conclusion The work of various authorities in the context of wood anatomy and other physical properties of wood leads to the following conclusions: 1. The anatomical structure of P. ciliata, P. alba, P.euphratica and P. deltoides is more or less similar, however, the colour differentiation in wood was reported; grey or brownish grey in P. ciliata, sapwood white and heartwood red coloured and black near the pith in P. euphratica, whereas white often with red or yellowish tinge in P. alba white to offwhite in P. deltoides. 2. Within ramet vertical and radial variations in wood traits namely fiber- and vessel element-dimensions and specific gravity were significant and nonsignificant for different clones of P. deltoides for different wood traits differently. It showed that some clones were stable for wood properties while some were not. Different clones do not follow the similar trend for the wood traits. 3. Intra- and inter – ramet significant variations for some of the clones of P. deltoides showed variation with in the population of same clone and different clones. Stable clones which showed within-tree and intra-clonal non-significant variations for wood traits may be preferred for stable wood properties in tree improvement program. 4. Higher fiber percentage showed mature properties of poplar clones. ENVIS 5. 6. 7. 8. Female dominance was reported for wood anatomical traits in P. deltoides. The plantation raised by two techniques, viz., micro- and macro-propagation could not produce similar type of wood even from the same clone. Intra-clonal variations in all the three clones of P. deltoides indicated that wood traits were not stable within the population of same clone grown by either method. The site variations also affect the wood properties of the micro-propagated plantation wood. The wood traits mostly inherited in P. deltoides from same parental sex to same offspring sex. Further, enhancement in the dimensions of wood traits in F1 male offsprings showed the influence of hybrid vigor. Higher heritability values and positive genetic gain for wood traits for P. deltoides showed that there was a great possibility of the improvement of the species for wood traits through different and defined breeding programs. References Ani, S. and Lim, S.C. 1993. Variation in specific gravity of five year old Acacia mangium from the Batu Arang Plantation, Selangor, Malaysia. Journal of Tropical Forest Science, 6(2): 203-206. Aziz, M. and Pande, P.K. 2008. Intra-ramet and inter-clonal variations in the dimensions of wood elements and specific gravity in male and female clones of Populus deltoides Bart. ex. Marsh. In: Uttarakhand State Science and Technology Congress, 3rd, Rookee, 1011 November 2008. Proceedings. p. 92 Aziz, M. and Pande, P.K. 2009. Preliminary studies on the inheritance pattern of wood traits in Populus deltoides Bart. ex. Marsh. In: Uttarakhand State Science and Technology Congress, 4th, Pantnagar, 10-12 November 2009. Proceedings. p. 18 Aziz, M. and Pande, P.K. 2010. Intra ramet variations of fiber dimensions in F1 female of Populus deltoides Bartr. ex. Marsh. In: Uttarakhand State Science and Technology Congress, 5 th , Dehradun, 10-12 November 2010. Proceedings. p. 182 Bamber, R.K. and Curtin, R.A. 1974. Some properties of wood of Blackbutt trees of two ages. Australian Forestry, 36(3): 226-234. Bamber, R.K. and Hamphreys, F.R. 1963. A preliminary studies of some wood properties of Eucalyptus grandis Forestry Bulletin, 12(1), 2012 (Hill) Maiden. Journal of the Institute of Wood Science, 11(1): 63-70. Barefoot, A.C.; Hitchings, R.G.; Ellwood, E.L. and Wilson, E.H. 1970. The relationship between loblolly pine fiber morphology and kraft paper properties. North Carolina Agricultural Experimental Station Technical Bulletin No. 202. Raleigh, NC., North Carolina State University. Bhat, K.M. 1990. Wood quality improvement of eucalyptus in India: An assessment of property variations. Journal of the Indian Academy of Wood Science, 21(2): 33-38. Boyce, S.G. and Kaiser, M. 1961. Environmental and genetic variability in the length of fibers of eastern cottonwood. Tappi, 44(3): 363-366. Burley, J. and Palmer, R.R. 1979. Pulp and wood densitometric properties of Pinus caribaea from Fiji. C.F.I. Occasional Paper No. 66p. Butterfield, R.P.; Crook, R.P.; Adams, R. and Morris, R. 1993. Radial variation in wood specific gravity, fiber length and vessel area for two central American hardwoods: Hyeronima alchorneoides and Vochysia guatemalensis: Natural and plantationgrown trees. IAWA Journal, 14(2): 153-161. Carvallo, A. 1962. Madeira de eucallipto (Eucalyptus globules Labill.). Estudos, ensaios e obseracoes. Direcao Geral Servicos. Floreatais e Aquicolas. Lisboa. Chaturvedi, A.N. 1982. Poplar farming in U.P. (India). U.P. Forest Bulletin No. 45. Forest Department, Uttar Pradesh. Chauhan, L.; Gupta, S.; Madhwal, R.C.; Pandey, R. and Pal, M. 2001. Interclonal, intraclonal and within tree variation in wood parameters of different clones of Populus deltoides. Indian Forester, 127(7): 777784. Chauhan, L.; Raturi, R.D. and Gupta, S. 1999. Studies on anatomical variations in different clones of Populus deltoides. Indian Forester, 125(5): 526-532. Cheng, W.W.D. and Bensend, W. 1979. Anatomical properties of selected Populus clones grown under intensive culture. Wood Science, 11(3): 182-187. Chudnoff, M. and Tischler, K. 1963. Fiber morphology of Eucalyptus camaldulensis Dehn. and the relation of wood anatomy to certain physical and mechanical properties. La-yaaran Supplement. Israel, Israel Forestry Association. 23p. Dadswell, H.E. 1957. Tree growth characteristics and their influence on wood structure and properties. In: British Commonwealth Forestry Conference, 7th, Australia, 1957. Proceedings. 145 Dadswell, H.E. 1958. Wood structure variation occurring during tree growth and their influence on properties. Journal of the Institute of Wood Science, 1: 1-24. Dalal, S.S. and Trigotra, R.C. 1983. Experiences in poplar cultivation outside forests. Indian Forester, 109(10): 726-736. Davidson, J. 1972. Variation, association and inheritance of morphological and wood characters in an improvement program for Eucalyptus deglupta Blume. Ph. D. thesis. Australian National University, Canberra. Davis, E.M. 1961. The effect of density upon wood properties. Woodworking and Furniture Digest, 63(9): 52-53. Debell, D.S.; Singleton, R.C.; Harrington, A. and Gartner, B.L. 2002. Wood density and fiber length in young Populus stems: Relation to clone, age, growth rate and pruning. Wood and Fiber Science, 34(4): 529539. Dinwoodie, J. M. 1961. Tracheid and fiber-length in timber - A review of literature. Forestry, 34: 125-144. Donaldson, L.A. 1992. Within and between tree variations in microfibril angel in Pinus radiate. New Zealand Jorunal of Forestry Science, 22:77-86. Einspahr, D.W; van Buijtenen, J.P. and Peckham, J.R. 1963. Natural variation and heritability in triploid aspen. Silvae Genetica, 12(2): 51-58. Erickson, H.D and Tsuneo Arima. 1974. Douglas-fir wood quality studies. Part-II: Effects of age and stimulated growth on fibril angle and chemical constituents. Wood Science and Technology, 8(4): 255-265. Evans, R.; Stringer, S. and Kibblewhite, R. P. 2000. Variation in microfibril angle, density and fiber orientation in twenty-nine Eucalyptus nitens trees. Appita Journal, 53(5): 450-457. Fang, S.; Wenzhong, Y. and Ye, T. 2006. Clonal and within tree variation in microfibril angle in poplar clones. New Forests, 31(3): 373-383. Farmer, R.E and Wilcox, J.R. 1966. Specific gravity variation in a lower Mississippi Valley cottonwood plantation. Tappi, 49(5): 210-211. Farmer, R.E. and Wilcox, J.R. 1968. Preliminary testing of eastern cottonwood clones. Theoretical and Applied Genetics, 38(5): 197-201. Florsheim, S.M.B.; Tomazello Filho, M. and Spegiorin, L. 1999. Variations in dimensions from pith to the bark and the stem base to the the top in trees ‘aroeira; Myracrodruon urundeuva F.F. Allemao (Anacardiaceae).II Vessels and rays. Revista do Institutu Florestal, 11(2): 159-171. 146 Foster, G.S. and Shaw, D.V. 1988. Using clonal replicates to explore genetic variation in perennial plant species. Theoratical Applied Genetics, 76(5): 788-794. Gamble, J.S. 1922. A manual of Indian timbers. 2nd ed. London, pp.690-692. Gautam, P. 2010. Multilocational trials of micro propagated L34 clone of Populus deltoides Bartr. Ex. Marsh: Analysis of wood anatomical properties and growth. Ph. D. thesis. Forest Research Institute University, Dehradun. Gautam, P. and Pande, P.K. 2008. Intra and inter -ramet variation in tissue culture raised plantation wood of L-34 clone of Populus deltoides Bart. ex. Marsh. In: Uttarakhand State Science and Technology Congress, 3rd, Roorkee, 10-11 November 2008. Proceedings. p. 93. Gautam, P. and Pande, P.K. 2009. Variation in wood anatomical properties in micro-propagated plantation in interlocation trials of l-34 clone of Populus deltoides Bart. ex. Marsh. In: Uttarakhand State Science and Technology Congress, 4 th , Pantnagar, 10-12 November 2009. Proceedings. p.11. Gautam, P. and Pande, P.K. 2010. Inter relationship among wood traits of tissue culture raised plantation wood of L-34 clone of Populus deltoides Bartr. ex. Marsh. In: Uttarakhand State Science and Technology Congress, 5th, Dehradun, 10-12 November 2010. Proceedings. p. 96. Gautam, P. and Pande, P.K. 2011. Variations in specific gravity of tissue culture raised plantation wood of L-34 clone of Populus deltoides Batr. ex Marsh at multilocation trials. In: National Symposium on Assessment and Conservation of Forest Genetic Resources through Biotechnological Interventions, Ranchi, 19-20 December 2011. Proceedings. Gilani, A.U.; Shah, A.J.; Ahmad, M. and Shaheen, F. 2006. Antispasmodic effect of Acorus calamus Linn. is mediated through calcium channel blockade. Phytotherapy Research, 20(12): 1080-1084. Honjo, K.; Fujitha, M. and Sahri, M.H. 2002. Radial variation in the morphology of axial elements in Acacia mangium. IAWA Journal, 23(4): 459-485. Hudson, I.; Wilson, L. and Beveren, K.V. 1998. Vessel and fiber property variation in Eucalyptus globules and Eucalyptus nitens: Some preliminary results. IAWA Journal, 19(2): 111-130. Idu, M. and Ijomah, J.U. 1996. Wood anatomy of some savanna Fabaceae species: Dimensional variation in fiber and vessel elements of Afzelia Africana Sm. Annals of Forestry, 4(2): 119-122. ENVIS Idu, M. and Ijomah, J.U. 2000. Wood anatomy of some savanna Fabaceae species: Dimensional variation in fiber and vessel elements of Daniellia oliveri (Rolfe) Hutch and Dalz. Indian Forester, 126(2): 149-153. Inokuma, T.; Shimaji, K. and Hamaya, T. 1956. Studies on poplars (I). Measurement of fiber-length and specific gravity of Japanese giant poplar (Populus japanogigas). Miscellaneous Information, the Tokyo University Forests, 11: 77-86. International Association of Wood Anatomists. 1989. List of microscopic features for hardwood identification. IAWA Bulletin, 10(3): 219 Ishiguri, F.; Eizawa, J.; Saito, Y.; Iizuka, K.; Yolota, S.; Priadi, D.; Sumiasri, N. and Yoshizawa, N. 2007. Variation in the wood properties of Paraserianthesis falcataria planted in Indonesia. IAWA Journal, 28(3): 339-348. Ishiguri. F.; Hiraiwa, T.; Iizuka, K.; Yokota, S.; Priadi, D.; Sumiasri, N. and Yoshizawa, N. 2009. Radial variation of anatomical characteristics in Paraserianthesis falcataria in Indonesia. IAWA Journal, 30(3): 343352. Ivkovich, M. 1996. Genetic variation of wood properties in balsam popular (Populus balsamifera L.) Silvae Genetica, 45(2-3): 119-124. Jayme, G.; Brancheid, F.; Harderrs-Steinhauser, M. and Eser, L. 1943. Eignungsvergleich verschiedener Schwarzpappelholzer zur Zellstoffgewinnung. Holz Roh-Werkst, 6: 231-240. Jha, K.K. and Gupta, C. 1991. Intercropping of medicinal plants with poplar and their phenology. Indian Forester, 117(7): 535-544. Jiang, X.M.; Yin, Y.F. and Urakami, H. 2003. Variation within tree of wood anatomical properties and basic density of I-214 poplar in Beijing area and their relationship modelling equations. Scientia Silvae Sinicae, 39(6): 115-121. Joong, H.W. and Joong, K.G. 2002. Anatomical characteristics of major Korean ash species. Journal of the Korean Wood Science and Technology, 30(2): 79-86. Jordan, L.; Daniels, R.F.; Clark, A. and He, R. 2005. Multilevel non-linear mixed effect-model for the modeling of earlywood and latewood microfibril angle. Forestry Science, 51(4): 357-371. Jorge Fatima.; Quilho, T. and Pereira, H. 2000. Variability of fibre length in wood and bark in Eucalyptus globules. IAWA Journal, 21(1): 41-48. Kaeiser, M. 1956. Variation in fibre length of eastern cotton wood. Report No. 2047. Madison, USDA. 6p. Forestry Bulletin, 12(1), 2012 Kaubaa, A.; Hernandez, A.E.; Beaudoin, M. and Polyguin, J. 1998. Interclonal, intra-clonal and within tree variationin fiber-length of poplar hybrid clones. Wood and Fiber Science, 30(1): 140-147. Keith, C.T. and Kellogg, R.M. 1986. Wood quality considerations in tree improvement programmes: Proceedings of a workshop Quebec City, August 19, 1985. Special Publication, SP-513E. Ottawa, Forintek Canada Corp. 77p. Kennedy, R.W. 1970. Specific gravity of early- and lateflushing Douglas fir trees. Tappi, 53(8): 1479-1481. Kholik, A and Marsoem, S.N. 2002. The physical properties and fiber dimensions of Acacia auriculiformis breeding trees. IAWA Journal, 23(4): 468. Knigge, W. and Koltzenburg, C. 1965. The influence of timber qualities and ecological conditions on the cell sizes and on the proportions of types of cell in hardwoods in the temperate zones. Meeting of the IUFRO, Section 41, Melbourne, October 1965. Procedings. Koch, P. 1985. Utilization of hardwoods growing on southern pine sites. 3v. Agriculture Handbook No. 605. Washington DC, USDA. 3710 p. Kumar, A. 2007. Growth performance and variability in different clones of Gmelina arborea Roxb. Silvae Genetica, 56(1): 32-36 Kumar, P.; Rao, R.V.; Shukla, S.R. and Sudheendra, R. 2006. Physical and mechanical properties of plantation grown Acacia mangium from Karnataka. Indian Journal of Forestry, 29(1): 31-34. Larson, P.R. 1967. Silvicultural control of the characterstics of wood used for furnish. In: Tappi Forest Biology Conference, 4th, New York, 1967. Proceedings. pp.143-150. Lewark , S. 1979. Wood characteristics in Norway spruce breeding programmes. In: IUFRO Joint Meeting Of Working Parties on Norway Spruce Provenances and Norway Spruce Breeding, Bucharest, 1979. Proceedings. Escherode, Lower Saxony Forest Research Institute. Lim, S.C. and Gan, K.S. 2000. Some physical and anatomical features of fourteen year old Acacia mangium. Journal of Tropical Forest Products, 6(2): 206-213. Lima, J.T.; Breese, M.C. and Cahalan, C. M. 2004. Variation in microfibril angle in Eucalyptus clones. Holzforschung, 58:160-166. Magnussen, S. and Keith, C.T. 1990. Genetic improvement of volume and wood properties of jack pine: Selection strategies. Forestry Chornicle, 66(3): 281286. 147 Mamit, J.D. 1986. Specific gravity of two reforestation species in Sarawak. Malaysian Forester Publication, 49(12): 72-78. Marsoem, S.N.; Hariyanti, E. and Lukmandaru, G. 2002. Radial and axial variation in the fibre dimension and cell proportions of Acacia auriculiformis. IAWA Journal, 23(4): 471-472. Mathur, R.S. and K.K. Sharma. 1983. Poplars in India. Indian Forester, 109(9): 591-631. McGraw, R.A. 1985. Wood quality factors in loblolly pine. Atlanta, Tappi Press. 89p. McKimm, R.J. and Ilic, Y. 1987. Characteristics of the wood of young fast grown trees of Eucalyptus nitens Maiden with special reference to provenance variation iii anatomical and physical characteristics. Australian Forestry Research, 17(1): 19-28. McMillan, C.W. 1973. Fibril angle of loblolly pine wood as related to specific gravity, growth rate and distance from pith. Wood Science and Technology, 7(4): 251255. Metcalfe, C.R. and Chalk, L. 1950. Anatomy of the dicotyledons. Vol. 1-2. Oxford, Clarendon Press. Murphey, W. K.; Bowersox, T.W. and Blankenhorn, P.R. 1979. Selected wood properties of young Populus hybrid. Wood Science, 11(4): 236-267. Nepveu, G. ; Keller, R. and Cross, E. 1978. Selection juvenile pur la qualite du bois chez certains peupliers noirs. Annales des Sciences Forestieres, 35(1): 69-92. Nicholls, J.W.P.1967. Selection criterion in relation to wood properties. Canberra, Australian Forest Research Working Group No.1 (Forestry) House. Nicholls, J.W. P. and Phillips, F.H. 1970. A preliminary study of coppice-grown Eucalyptus as a source of chip material. Division of Forest Products Technological Paper No. 58. Melbourne, CSIRO. Pande, P.K. 2011. Inheritance pattern of wood anatomical traits in Populus deltoides Bartr. ex Marsh. FRI-446/BOT64, PCR submitted to Indian Council of Forestry Research and Education, Dehradun. 203p. Pande, P.K. 2011a. Variations in wood properties and growth in some clones of Populus deltoides Bartr. ex Marsh. American Journal of Plant Sciences, 2(5): 644-649. Pande, P.K. and Dhiman, R.C. 2010. Variations in wood traits in micro and macro propagated plantation woods of Populus deltoides Bartr. ex Marsh. Advances in Bioscience and Biotechnology, 1(1): 30-38. Pande, P.K. and Dhiman, R.C. 2011. Performance and variability patterns in wood properties and growth traits in the parents, F1 and F2 generation hybrid 148 clones of Populus deltoides. Journal of Forestry Research, 22(3): 379-385. Pande, P.K. and Dhiman, R.C. 2012. Variations in wood anatomical properties and specific gravity of half sib progenies of Populus deltoides Bartr. ex Marsh. Journal of Forestry Research, 23(3): 491-496. Pande, P.K. and Singh, M. 2005. Intraclonal, inter - clonal and single tree variations of wood anatomical properties and specific gravity of clonal ramets of Dalbergia sissoo Roxb. Wood Science Technology, 39(5): 351366. Pande, P.K. and Singh, M. 2009. Individual tree, intra- and inter-clonal variations in wood properties of the clonal ramets of Eucalyptus tereticornis Sm. Indian Forester, 135(5): 629-646. Pande, P.K.; Aziz, M.; Uniyal, S. and Dhiman, R.C. 2012. Variation in wood anatomical properties and specific gravity in relation to sexual dimorphism in Populus deltoides Bartr. ex Marsh. Current Science,102(11): 1580-1585. Pande, P.K.; Naithani, S.; Kothiyal, V.; Mohanta, S.S.; Juyal, N. and Rawat, R. 2008. Intra- and inter-tree variations in physico-chemical and wood anatomical features in Leucaena leucocephala (lam.) de Wit. Indian Forester, 134(5): 622-632. Pande, P.K.; Rao, R.V.; Agrawal, S.P. and Singh, M. 1995. Variation in the dimensions of trachied elements of Pinus caribaea var. bahamensis. Journal of Tropical Forest Products, 1(2): 117-123. Pearson, R.S. and Brown, H. P. 1932. Commercial timbers of India. Vol. 1-2. Calcutta, Central Publication Branch, Government of India. Peszlen, I. 1994. Influence of age on selected anatomical properties of Populus clones. IAWA Journal, 15(3): 311-321. Phelps, J.E.; Isebrands, J.G. and Jowett, D. 1982. Raw material quality of short rotation intensively cultured Populus clones. A comparision of stem and branches properties at three species. IAWA Journal, 3(3-4): 193-200 Philips, E.W.J. 1941. The inclination of fibrils in the cell wall and its relation to the comparison of timber. Empire Forestry Journal, 20: 74-78. Purkayastha, S.K.; Agarwal, S.P.; Farooqui, P.; Tandon, R.D.; Chauhan, L. and Mishra, N. 1979-1980. Evaluation of wood quality of Eucalyptus plantations in various states. Final Technical Report, PL480 Project No. Inn FS-66, 85p. Purkaystha, S.K.; Lal, K.; Rao, K. R. and Negi, G. S. 1974. Variation in structure and density within a single ENVIS tree of Michelia champaca Linn. Indian Forester, 100(7): 453-465. Ramirez, M.; Rodriguez, J.; Peredo, M.; Valenzuela, S. and Mendonca, R. 2009. Wood anatomy and biometric parameters variation of Eucalyptus globulus clones. Wood Science and Technology, 43(1-2): 131-141. Rao, B.S.S. and Rao, R.V. 1978. Variation in length of vertical elements within one tree of Betula pubercens Ehrh. Journal of the Indian Academy of Wood Science, 9(2): 105-110. Rao, R.V. and Sujatha, M. 2004. Variation in basic density and anatomical properties of plantation grown in Acacia mangium. Journal of the Timber Development Association of India, 50(3-4): 12-17. Rao, R.V.; Shashikala, S.; Sreevani, P.; Kothiyal, V.; Sharma, C.R. and Lal, P. 2002. Within tree variation in anatomical properties of some clones of Eucalyptus tereticornis Sm. Wood Science and Technology, 36(3): 271-285. Rao, R.V.; Shashikala, S; Sujatha, M. and Sharma, C.R. 2003. Variation in anatomical properties in certain hardwoods. Journal of the Timber Development Association of India, 49(1-2): 44-57. Rao, R.V.; Sujatha, M. and Hemawathi, T.R. 2003a. Radial variation in anatomical properties of plantation grown Tecomella undulata. Journal of Tropical Forest Products, 9(1-2): 68-76. Rao, R.V.; Sujatha, M.; Shashikala, S. and Sharma, C.R. 1996. Wood anatomical variations in certain hardwood trees. Journal of the Timber Development Association of India, 42(2): 25-38. Raturi, R.D.; Chauhan, L.; Gupta, S.and Rao, R.V. 2001. Indian woods- Their identification, properties and uses. Vol. 6. Dehradun, ICFRE. 197p. Reck, S. 1974. Growth and wood characterstics in clones of Populus trichocarpa grown in West Germany and their significance for selection. In: IUFRO joint Meeting of Working Parties on Population and Ecological Genetics Breeding Theory and Progeny Testing, Stockholm, 1974.Proceedings. Stockholm, Departmnet of Forest Genetics, Royal Challenge of Forestry. Roszaini, A.K. 2000. Effect of age and height on the stem characteristics of Calamus scipionum (rotan semambu). Journal of Tropical Forest Products, 6(2): 190-199. Sahri, M. H.; Ibrahim, F.H. and Nor Aini, A.S. 1993. Anatomy of Acacia mangium grown in Malayasia. IAWA Journal, 14(3): 245-251. Forestry Bulletin, 12(1), 2012 Scaramuzzi, G. 1955. Dimensional data about fibers in Populus x euramericana (dode) guinier cv “1-214”. Report of the 8 th Session of the International Poplar Commission, Madrid, 25-28 April 1955. Rome, FAO. 20p. Sining, U.N. 1989. Some wood properties of Acacia mangium Willd. from three provenances grown in Sabah. Forest Research Centre Publication, No.56. 66p. Song, W.; Zhang, Z.Y. and Xu, J.R. 1997. Study on inheritance and variation of wood basic density of Populus tomentosa Carr. clones. Journal of Beijing Forestry University, 6(1):8-18. Susilawati, S.; Susanto, M. and Chigira, O. 2002. Wood properties variation among plus tree candidates of Acacia mangium. IAWA Journal, 23(4): 479. Tajima, T. 1967. Tree growth and wood properties. Research Report. Tokyo, Faculty of Agriculture, Tokyo University. 208p. Tomazello, F. and Variacano, M. 1987. Rradial da densidade basica e da estrutura anatomica da Madeira do Eucalyptus globules e E. pellita e E. acmeniodies. Instituto de Pesquisas e Estudos Florestais No. 36. Vainio, U.; Anderson, S.; Serimaa, R.; Paakkari, T.; Saranpaa, P.; Treacy, M. and Evertsen, J. 2002. Variation in microfibril angle between four provenances of Sitka spruce (Picea sitchensis). Plant Biology, 4(1): 27-23. Van Buijtenen, J.P. 1962. Heritability estimates of wood density in loblolly pine. Tappi. 45(7): 602-605. Van Buijtenen, J.P. 1986. Computer simulation of the effect of wood specific gravity and rotation age on the production of liver board and multiwall sack paper. In: TAPPI Research and Development Conference. Proceedings. Atlanta, TAPPI Press. Van Buijtenen, J.P.; Joranson, P.N. and Einspahr, D.W. 1958. Diploid versus triploid aspen as pulpwood sources with reference to growth, chemical, physical, and pulping differences. Tappi, 41(4): 170-175. Vargas-Hernandez, J. and Adams, W.T. 1991. Genetic variation of wood density components in young coastal Douglas- fir: Implications for tree breeding. Canadian Journal of Forest Research, 21(12): 18011807. Veenin Teera; Minoru Fujita; Tadashi Nobuchi and Somkid Siripatanadilok 2005. Radial variations of anatomical characteristics and specific gravity in Eucalyptus camaldulensis clones. IAWA Journal, 26(3): 353361. Venkaiah, K.; Chauhan, R. and Khurana, D.K. 2007. Wood characteristics of twenty poplar clones grown under 149 short rotation intensive culture in Himachal Pradesh. Journal of the Timber Development Association India, 52(1-2): 3-21. Vurdu Hasan and Bensend Dwight, W. 1979. Specific gravity and fiber length in European black alder roots, branches and stems. Wood Science, 12(2): 103-105. Williams, R.F. and Hamilton, J.R. 1961. The effect of fertilization on four wood properties of slash pine. Journal of Forestry, 59(9): 662-665. Wu, S.C and Wang, Y.C. 1988. The wood properties of Acacia mangium and Acacia auriculiformis. Journal of the Experimental Forest of National Taiwan University, 2(4): 59-88. Xu Bin; Tu Dao Wu; Wang You Hong and Zha Chao Sheng. 2004. Comparative study on anatomical feature of the main structure of the common ‘wingceltis’ floor. Journal of Anhui Agricultural University, 32(2): 198-202. Xu Youming, Chen Shiyin and Fang Wenbin. 1999. Variation of tracheid length and microfibril angle of slash pine in different sites and their correlation. Journal of Huazhong Agricultural University, 18(1): 83-87. Yanchuk, A.D.; Dancik, B. P. and Micko, M. M. 1983. Intraclonal variation in wood density of trembling aspen in Alberta. Wood Fiber Science, 15(4): 387394. Yang, W.Z and Zuo, F. S. 2003. Variation of fiber length and fiber width for seven popular clones. Journal of Nanjing Forestry University, 27(6): 23-26. Zha, C.S.; Yu Fang; Liu Shengquan and Bin Wang. 2005. Radial variation of fiber morphology of different 150 poplar clones. Journal of Anhui Agricultural University, 32(2): 192-197. Zhang, B.; Fei, B.H.; Yu, Y. and Zhao, R.J. 2007. Microfibril angle variability in Massion pine (Pinus massoniana Lamb.) using X-ray diffraction. Foresrty Studies in China, 9: 33-38. Zhang, S.Y. 1995. Effect of growth rate on wood specific gravity and selected mechanical properties in individual species from distinct wood categories. Wood Science Technology, 29(6): 451-465. Zhang, S.Y. and Chui, Y.H. 1996. Selecting dry fiber weight for higher and better quality jack pine fiber production. Wood and Fiber Science, 28(2): 146152. Zobel, B.J. 1961. Inheritance of wood properties in conifers. Silvae Genetica, 10(3): 65-70. Zobel, B.J. 1964. Breeding for wood properties in forest trees. Unasylva,18: 89-103. Zobel, B.J. 1965. Inheritance of fiber characteristics and specific gravity in hardwoods – A review. In: Meeting of Section 41, Forest Products, IUFRO, 1113 September 1963. Proceedings. Madison, USDA. Zobel, B.J. 1973. Biostratigraphische untersuchungen an sedimenten des indisch-pakistanischen kontinentalrandes (Arabisches Meer). - ‘Meteor’ Forschungsergebnisse, C(12): 9-73. Zobel, B.J. and Talbert, J. 1984. Applied forest tree improvement. New York, John Wiley. 511p. Zobel, B.J. and van Buijtenen, J.P. 1989. Wood variation: Its causes and control. Berlin, Springer-Verlag. 363p. z ENVIS Mapping Research on Poplar (Populus spp.) in ‘Forest Science Database’ Arundhati Kaushik1, Ritu Negi2, Santan Barthwal3 and Y. P. Singh4 1 G. B. Pant University of Agriculture and Technology, Pantnagar - 263 145 2 ENVIS Centre on Forestry FRI, Dehradun - 248 006 3 Genetics and Tree Propagation Division, FRI, Dehradun - 248 006 4 Forest Pathology Division, FRI, Dehradun - 248 006 Introduction T Considerable amount of research and development work had been carried out in poplars to meet the needs of farmers and industries. Growth of scientific and technical literature is a related manifestation Forestry Bulletin, 12(1), 2012 he Populus genus consists of more than thirty species distributed across the cold temperate region in northern hemisphere. According to the foreword of 23rd Session of International Poplar Commission, Beijing, China... Poplars and willows contribute significantly to people, their lives, and livelihoods through the provision of wood products (industrial roundwood and poles, pulp and paper, reconstituted boards, plywood, veneer, sawn timber, packing crates, pallets, furniture, etc.), non-wood products (fodder, medicines, etc.) and environmental and social services (shelter, shade and protection of soil, water, crops, livestock and dwellings). Poplars and willows play an important role in phyto-remediation of severely degraded sites, rehabilitation of fragile ecosystems, landscape restoration, sequestration of carbon and, increasingly, as a viable source of bioenergy. The environmental applications of poplars and willows are also being recognized as effective means for recreational and amenity purposes. Of late, multifarious uses of crops like poplar have made inroads to the livelihood issues of people in both developed and developing economies. Populus deltoides Marsh. is one of important commercial timber species of the genus, introduced in India for mainly match industry. Other species of the Populus genus like Populus ciliata, P. alba, P. euphratica, P. gamblii, P. jacquemontii var. glauca and P. rotundifolia are indigenous to India and are potential species as raw material for wood and pulp based industries. In India, poplars are extensively cultivated in states of Punjab, Haryana, Uttar Pradesh, Uttarakhand and also in some parts of lower Himachal Pradesh, Jammu and Kashmir in agroforestry system. Poplars cultivation has played and still continues to play very important and significant role in strengthening rural economy, thereby, improvement of life of farmers. Plantations in the Tarai regions of Uttarakhand and fertile lands of Punjab and Haryana have helped in generation of employment and improvement of livelihood of the common people. In the last decade, considerable amount of research and development work had been carried out in poplars to meet the needs of farmers and industries. Growth of scientific and technical literature is a related manifestation. Therefore, an attempt was made to carry out bibliometric analysis of the published records on poplars. 151 Bibliographical databases are repository of these bibliographic or publication records. These databases provide an index of articles published in multiple journals including citations, abstracts and even a link to the full text (free or paid). Forest Science Database is the world’s richest bibliographic database on forestry and allied disciplines like wood science, agroforestry, etc. It is a source not only for literature survey for research but also an important tool to study trends in research and development in selected, focused topic in forest science. Eleven-year data (2000-2011) on poplars appearing in title or abstract fields in the records of Forest Science Database was analyzed with objectives to identify year-wise distribution of indexed documents, publication types, geographical distribution, language, authorship pattern and ranking of journals. Review of Literature Bibliometric or literature mapping studies are available in important subject areas which are referred by wider readers of subject areas such as medicine, social science, climate change, natural disasters, etc. Arrebola and García (2002) in their study observed that international research in pharmaco-epidemiology presents an exponential growth pattern in accordance with Price’s law. There is a large degree of publishing dispersion. Indian Pharmaceutical Association (IPA), a premier professional association of pharmacists in India, publishes bibliographic databases that have the greatest number of original articles; nearly half of which were published in pharmaco-epidemiology and drug safety. These databases are, therefore, considered to be appropriate for bibliometric studies in the field of pharmacoepidemiology. Ruiz-Perez et al. (2002) in their research on Spanish personal name variations in national and international biomedical databases investigated how Spanish names were handled by national and international databases and to identify mistakes that can undermine the usefulness of these databases for locating and retrieving works of Spanish authors. Russell and Rousseau (2002) in their study entitled ‘Bibliometrics and institutional evaluation’ observed that literature-based or bibliometric indicators, which quantify the production and use of bibliographic material, have been used extensively in the assessment of research performance. The potential of web-based electronic sources for providing comprehensive and accurate production and citation data for bibliometric analysis coupled with the capacity of the Internet to integrate information from a large number of different sources, promises to revolutionize the way indicators 152 are constructed by eliminating many of the methodological constraints experienced today. Wolfgangglanzel (2002) in his study of co-authorship patterns and trends in the sciences from year 1980-1998 described both common and the distinguishing features of co-authorship trends and patterns in selected science fields. The relation between coauthorship schemes and other bibliometric features, such as publication activity and citation impacts were also analyzed in the study. Moed et al. (2009) in their research report revealed that the creation of databases of social sciences and humanities in Spain for research development is expected to go on; Thomson Reuters and Elsevier will further enhance the coverage of 50 social sciences and humanities fields; Google will further enhance its products ‘Scholar’ and ‘Book Search’ and possibly integrate them; and institutional repositories and research management systems will further develop. He Ping et al. (2009) analysed published work on invasive alien species in forestry. Poplar, an important tree species, is one of the choice species of research for forest scientists. First time, Gao Jie et al. (2010) carried out detailed bibliographic analysis of core journals on poplar research in China. They had statistically analyzed the number of papers, their year-wise and periodicals distribution, research subjects, core authors, etc. in the core journals from 2000 to 2009 with the help of literature methodology to demonstrate the research status and level and technological achievements in this subject. Recently, Chong et al. (2012) analysed the engineering research papers engaged in the area of ‘conversion of farmland back to forests’ in China from 1999 to 2010, on aspect of the annual variation in output volume, the authors’ institutions, distribution of journals and disciplines, published topics and authors’ collaboration degrees. Materials and Methods Forest Science Database, a world’s leading bibliographic database on forestry containing data of CABI, U.K., published by Ovid Technologies, Wolters Kluwer was selected for the study. It index documents on forest, forestry, wood science, agroforestry research, etc. and is closely associated with the continued advancement in forestry in the world. It covers all aspects of forestry, its administration, management and information on recent development in researches carried out in the world. It is one of the core bibliographical databases most consulted by the scientists and researchers for primary information in forestry. All the research publications indexed in the database during 2000- ENVIS 2011 containing poplar or Populus in abstract or title fields were browsed accessing them through scanned and selected considering year-wise distribution of indexed documents, publication types, geographical distribution, language, authorship pattern and ranking of journals. Finally, all the collected data was manually entered into an Microsoft Excel (2007) and analyzed for trends. Language of the Published Articles The records in different languages are presented in Table 1. Languages with less than 5 records are clubbed together under the heading ‘others’. Text of the indexed journals was in 30 languages. Maximum indexed journals were in English (6,485) as it is an international language for scientific Results Distribution of the Number of Indexed Documents Published During 2000 – 2011 The year wise distribution (2000-2011) of the indexed documents is presented in Fig. 1. The total number of contributed research papers was 8,946. It was observed that maximum number of research papers; i.e. 1,079 (12.6 per cent) were published in the year 2010. The lowest number of research papers of 606 (6.8 per cent) were published in the year 2003. On an average, more than 800 research papers on poplars were published during the period. Overall, there was an increasing trend in number of articles appearing on poplars during the study period. The number of publication dipped in the year 2003 and 2009. However, sharp increase in the literature on poplars was recorded after 2003 and 2009. Geographical Distribution of the Indexed Journals Publishing Articles on Poplars Of 8,946 records appearing in the Forest Science Database, there were maximum numbers of publications from USA (2,415) followed by China (2,089). Canada also published a good number of papers; i.e., 1,168. Yugoslavia (823) and India (593) had close tally (Fig. 2.). The data indicates that the publications on poplar were significantly growing in China making it second to USA. Fig. 1. Yearly distribution of documents from 2000-2011. Forestry Bulletin, 12(1), 2012 Fig. 2. Country wise distribution of the published articles on poplars. Table 1. Language of text of the articles Language Total no. of records Bulgarian Chinese Croatian Czech Dutch English Estonian French German Hungarian Italian Japanese Korean Lithuanian Persian Polish Portugese Romanian Serbian Slovakian Spanish Swedish Turkish Others (countries with less than five records) Total Per cent 9 1,352 30 15 15 6,485 15 175 134 16 153 14 33 13 112 36 18 24 34 22 91 9 28 113 0.1 15.1 0.3 0.2 0.2 72.5 0.2 2.0 1.5 0.2 1.7 0.2 0.4 0.2 1.3 0.4 0.2 0.3 0.4 0.3 1.0 0.1 0.3 1.3 8,946 100.0 153 communication. It was followed by Chinese (1,352), French (175), Italian (153), German (134) and Persian (112) which had at least 100 numbers. Hindi language journals were not included in this database. There is a need for promotion of Hindi in forestry research publications, so that, both common man and professional can consult them. Considerable literature is available in Chinese that, unfortunately, not consulted by non Chinese researchers. It makes a strong case of translation into English for larger dissemination of information to the poplar research groups around the world. Contribution of Authors Authors’ contribution was also analysed and it was found that each publication has single as well as multiple authors. Ten thousand nine hundred and eight authors contributed only one time followed by 2,017 (two times), 277 (three times), 152 (four times), 86 (five times), 95 (six times), 36 (seven times), 26 (eight times), 17 (nine times) and 9 (10 times) and so on (Table 2). Top 10 authors with more than 17 contributions are presented in Fig. 3 and other authors with less than 18 contributions are presented in Fig. 4. Table 2. Number of authors and their contributions Author 1 1 1 1 1 2 2 3 3 4 5 6 8 9 Contribution 52 48 29 24 17 30 23 21 19 16 20 15 18 14 Author 9 12 15 17 17 26 36 86 95 152 277 2,017 10,908 Contribution 10 13 12 11 9 8 7 5 6 4 3 2 1 Fig. 3. Scientific contribution of top ten authors. 154 Fig. 4. Scientific contributions of other authors. Publication Types Research results are primarily published in journal, conference proceedings, book chapters and theses. Table 3 lists out various types of documents containing research information on poplars during 2000-2011. In the present study, it was observed that maximum literature published as journal articles (8,066) followed by book chapters or conference papers (343) and, then conference papers published in journals (338). Other types of publications included bulletins, bulletin articles, journal issues, books and book chapters. The number and forms of information sources are continuously increasing with advances in information technology. Journals and Their Ranking Forest Ecology and Management, Scientia Silvae Sinicae, Canadian Journal of Forest Research, Tree Physiology, Journal of Northeast Forestry University, Journal of Beijing Forestry University, Indian Forester are top journals publishing over 100 articles on poplars from year 2000- Table 3. Publication types of indexed journals Publication type Annual report Book Book chapter Book chapter; Conference paper Bulletin Bulletin article Conference proceedings Correspondence Journal article Conference papers published in journals Journal issue Miscellaneous Thesis Total Total no. of records 06 16 62 343 64 30 02 01 8,066 338 24 20 04 8,976 Per cent 0.1 0.2 0.7 3.9 0.7 0.3 0.02 0.01 89.9 3.8 0.3 0.2 0.04 100.0 ENVIS 2011. More number of journals in Chinese language (Table 4) is probably is one of the reasons for having large number of articles in the Chinese language. In spite the more numbers of publications, the impact factor of the Chinese journals was low. The position of other journals was-60 journals (10-50 times); 699 journals (1 time); 634 journals (2-9 times). Table 4. Ranking of highly indexed journals based on number of papers on poplars Source Total no. of records Forest Ecology and Management 230 Scientia Silvae Sinicae 212 Canadian Journal of Forest Research Tree Physiology Journal of Northeast Forestry University Journal of Beijing Forestry University Indian Forester 197 154 151 145 117 Journal of Nanjing Forestry University Natural Sciences Edition New Phytologist Plant Physiology Forest Research, Beijing Forestry Studies in China Biomass and Bioenergy Forest Products Journal Holzforschung Bulletin Trimestriel Centre de Populiculture du Hainaut Plant, Cell and Environment Wood and Fiber Science Environmental Pollution Acta Botanica Boreali Occidentalia Sinica Annals of Forest Science Canadian Journal of Botany 97 90 89 86 75 73 69 69 58 54 54 53 52 52 51 Discussion Poplar along with willow is grown in about 70 countries with its area exceeding 80 million hectares. The Russian Federation, Canada and the United States have the largest reported areas of naturally occurring poplar and willows, while China, India and Pakistan have the largest planted areas (Ball and Lungo, 2005). As per the synthesis of country progress report of the 23 rd Session of the International Poplar Commission held at China, there was a positive trend in the growth of area under poplar cultivation in US, China and India grown in agroforestry or trees outside forest area. In China, this area was 1,000,000ha which increased to Forestry Bulletin, 12(1), 2012 2,500,000ha in 2007. In India, this figure was 60,000 ha in both years. Canada had also shown increase in the planted area from 9,000 to 14,000 ha. As plantation there was increase in the area from 3,900,000 to 4,300,000ha in China. There was no change in area under indigenous poplar in USA and India and positive increasing trend in China for indigenous polar. This explains the voluminous publications on poplars from China close to USA. It also indicates that maximum work on poplars is being carried out in developed countries like USA. However, developing country like China is closely following the USA. Science refines production tools and means of production - in the present case the production technology of poplars. China, a planned economy, reflects this interconnection best in terms of expanding area under poplars as well as raising quantity and quality of research efforts and publications. This relationship may not be so simple in countries like India and needs critical investigation. Journal articles and conference papers are choice publication type for researchers around the world. Largest numbers of publications on poplars were published in journals like Forest Ecology and Management, Scientia Silvae Sinicae, Canadian Journal of Forest Research, etc. To link the research output (in terms of publication) with societal needs, it is essential to map the data based on the subject/discipline for identification of gaps. References Arrebola-Pascual, I.; García-López, J.A. 2002. Presence of pharmacoepidemiology in three bibliographic databases: Medline, IPA and SCI. Pharmacoepidemiol Drug Safety, 11(6): 499-502. Ball, J. Carle, J. and Del Lungo, A. 2005. Contribution of poplars and willows to sustainable forestry and rural development. Unasylva, 56(221):3-11. Gao Jie. 2010. Bibliographic analysis of core journals on poplar research in China. Journal of Anhui Agricultural Sciences [http://en.cnki.com.cn/Article_en/ CJFDTOTAL-AHNY201036203.htm]. He Ping; Luo YouQing; Lu WenRu 2009. A bibliometric analysis on global literatures of invasive alien species of forest. Journal of Beijing Forestry University, 31(6): 77-85. IPC, 2008.(23rd Session of the International Poplar Commission, Beijing, 27th to 30th October 2008). 2008. Synthesis of country progress report. [Available at: http://www.fao.org/forestry/758209be6374a779c7ed84d17740bab940858.pdf]. 155 Moed, H.F.; Linmans, J.; Nederhof A.; Alesia Zuccala Carmen López Illescas and Felix de Moya Anegón. 2009. Options for a Comprehensive Database of Research. Research report. Netherland; Spain: European Science Foundation (ESF). [Available at: http:// 83.143.5.70/download/pdf/foerderung/ grundlagen_dfg_foerderung/ informationen_fachwissenschaften/ geisteswissenschaften/annex_2_en.pdf]. Ruiz-Pérez, R.; Delgado López-Cózar, E. and JiménezContreras, E. 2002. Spanish personal name variations in national and international biomedical databases: Implications for information retrieval and bibliometric studies. Journal of Medical Library Association, 90(4): 411-430. 156 Russell, Jane M. and Rousseau, Ronald. 2002. Bibliometrics and institutional evaluation. [Available at: http:// w w w. v u b . a c . b e / B I B L I O / i t p / l e c t u r e r s / ronald_rousseau/ronald_roussea _stim1_bibliometrics_russell.pdf]. Wolfgangglanzel. 2002. Coauthorship patterns and trends in the sciences (1980- 1998): A bibliometric study with implications for database indexing and search strategies. Library Trends, 50(3): 461-473. Ye Chong; Cai Shi-Zhen; Hu Ting-Xing 2012. Bibliometric analysis of research literature on conversion of farmland back to forests. Guangdong Agricultural Sciences, 2012-02. [Available at: http:// e n . c n k i . c o m . c n / A r t i c l e _ e n / C J F D TO TA L GDNY201202069.htm]. z ENVIS Research on Poplars in India: A Select Bibliography (1997-2011) 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. Ahluwalia, Rajani. 2010. Biology of Phalantha phalantha Drury (Lepidoptera: Nymphaliidae), a pest of Populus deltoides Bartr. Indian Forester, 136(8): 1119-1124. Ajit; Das, D. K.; Chaturvedi, O. P.; Nighat Jabeen and Dhyani, S.K. 2011. Predictive models for dry weight estimation of above and below ground biomass components of Populus deltoides in India: Development and comparative diagnosis. Biomass and Bioenergy, 35 (3): 1145-1152. Alpana; Biswas, S. 1999. Taxonomic evaluation of some important clones of poplar through studies on their winter buds. Indian Journal of Forestry, 22(4): 391-393. Aminder Kaur and Rao, P.B. 1998. Allelopathic effect of four agroforestry tree species on seed germination of certain varieties of wheat. Annals of Forestry, 6(1): 110-115. Anant Prakash and Srivastava, H.S. 2000. Growth and nitrogen assimilation in Populus in response to growth regulators and varying nitrate levels. Proceedings of the National Academy of Sciences India Section B, Biological Sciences, 70(1): 53-60. Anil Kumar; Hooda, M. S. and Dhillon, R.S. 1998. Influence of tree windbreaks on the yield of wheat (Triticum aestivum) in semi-arid regions of India. Indian Journal of Forestry, 21(3): 208-213. Babu, S.R.; Dahiya, K.K. and Suganthi, A. 2001. Incidence of sorghum shoot fly and stem borer in forage sorghum grown under poplar, Populus deltoides Marsh. based agri-silviculture system. Journal of Entomological Research, 25(4): 303308. Bahar, N. 2001. Demographic analysis of undergrowth vegetation under Populus tremuloides Michx., forests in North America. Indian Forester, 127(2): 199-206. Ballal, A.N.; Gogate, M.G.; Dakshindas, S.D. and Karunakaran, M. 2001. Introduction of poplar species in Maharashtra state – an assessment. Indian Forester, 127(1): 30-43. Bansal, A.K.; Narayanaprasad, T.R. and Mathews, K.C. 2002. Plywood from plantation species – Forestry Bulletin, 12(1), 2012 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. Populus deltoides (poplar). Indian Forester, 128(1): 75-80. Banuelos, G.S.; Dhillon, K.S.; Burken, J.G. and White, J.C. 2011. Developing a sustainable phytomanagement strategy for excessive selenium in Western United States and India. International Journal of Phytoremediation, 13 (Supplement 1): 208-228. Beig, M. A. and Khan, M.A. 1999. Occurrence of Venturia acerina, the perfect state of Cladosporium humile, on Populus deltoides in India. Applied Biological Research, 1(2): 163-165. Bhagat, R.C. 2011. Aphid pests (insecta) damaging forest – trees in Jammu, Kashmir and Ladakh Himalayas: An updated annotated checklist and biodiversity. Indian Forester, 137 (12): 1439-1444. Bhardwaj, S.D.; Panwar, Pankaj and Gautam, Sachil. 2001. Biomass production potential and nutrient dynamics of Populus deltoides under high density plantations. Indian Forester, 127(2): 144-153. Bhardwaj, S.D.; Panwar, Pankaj and Gautam, Sachil. 2001. Wood characteristics of Populus deltoides as affected by high density plantation. Indian Forester, 127(2): 255-256. Bhrot, N.P. and Khurana, D.K. 2001. Variability studies for some root characters in different clones of poplar. Indian Journal of Forestry, 24(2): 150-152. Bisht, R.S.; Rana, D.S. and Mishra, P.N. 2002. Vertical distribution and biology of Epipemphigus imaicus on Populus ciliata in Garhwal hills. Indian Journal of Entomology, 64(3): 343-350. Bisht, Sandeep; Pandey, Piyush; Sood, Anchal; Sharma, Shivesh and Bisht, N.S. 2010. Biodegradation of naphthalene and anthracene by chemo-tactically active rhizobacteria of Populus deltoides. Brazilian Journal of Microbiology, 41(4): 922-930. Chandra, J.P. 2001. Scope of poplar cultivation. Indian Forester, 127(1): 51-60. Chandra, J.P.; Chauhan, S.K.; Sharma, R.; Garg, R.K.; Singh, K. and Saralch, H.S. 2011. Development of poplar based agroforestry system. Indian Journal of Ecology, 38(Special Issue): 11-14. 157 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 158 Chandra, J.P.; Gandhi, J.N. and Joshi, B.C. 2001. Clonal trial on Populus deltoides in Tarai region of Uttaranchal. Indian Forester, 127(2): 257-259. Chaturvedi, A.N. 1997. Populus euphratica - a promising species for pulpwood plantation. Indian Forester, 123(11): 981-985. Chaturvedi, H.C.; Sharma, A.K.; Agha, B.Q.; Jain, M. and Sharma, M. 2004. Production of cloned trees of Populus deltoides through in vitro regeneration of shoots from leaf, stem and root explants and their field cultivation. Indian Journal of Biotechnology, 3(2): 203-208. Chaturvedi, O.P. and Pandey, I.B. 2001. Yield and economics of Populus deltoides Marsh based intercropping system in Eastern India. Forests, Trees and Livelihoods, 11(3): 207-216. Chaudhary, Lakshmi and Tewari, S.K. 2003. Identification of poplar (Populus deltoides Bartr.) clones through leaf protein profiling. Indian Journal of Genetics and Plant Breeding, 63(3): 287. Chauhan, H. S.; Singh, Kamla and Patra, D.D. 1997. Studies on litter production, nutrient recycling and yield potential under (5-6 years old) poplar (P. deltoides) and Eucalyptus (E. hybrid) interplanted with aromatic crops in Tarai region of Uttar Pradesh. Journal of Medicinal and Aromatic Plant Sciences, 19(4): 1034-1038. Chauhan, H.S. 2000. Performance of poplar (Populus deltoides) based agroforestry system using aromatic crops. Indian Journal of Agroforestry, 2: 17-21. Chauhan, H.S.; Kalra, A.; Mengi, N.; Rajput, D.K.; Patra, N.K. and Singh, K. 2000. Performance of menthol mint (Mentha arvensis) genotypes to varying levels of nitrogen application under poplar based agroforestry system in Uttar Pradesh foot hills. Journal of Medicinal and Aromatic Plant Sciences, 22(1B): 447-449. Chauhan, Luxmi; Gupta, Sangeeta; Madhwal, R.C. and Pandey, Rajiv. 2001. Studies on the effect of spacing on the wood quality in some clones of Populus deltoides. Indian Forester, 127(1): 101-106. Chauhan, Luxmi; Gupta, Sangeeta; Madhwal, R.C.; Pandey, Rajiv and Mohinder Pal. 2001. Interclonal, intraclonal and within tree variation in wood parameters of different clones of Populus deltoides. Indian Forester, 127(7): 777-784. Chauhan, Luxmi; Raturi, R.D. and Gupta, Sangeeta. 1999. Studies on anatomical variations in different 32. 33. 34. 35. 36. 37. 38. 39. 40. 41. 42. clones of Populus deltoides. Indian Forester, 125(5): 526-532. Chauhan, N.; Negi, M.S.; Sabharwal, V.; Khurana, D.K. and Lakshmikumaran, M. 2004. Screening interspecific hybrids of Populus (P. ciliata x maximowiczii) using AFLP markers. Theoretical and Applied Genetics, 108(5): 951-957. Chauhan, P.S. and Dey, A.N. 1999. Productivity potential of Populus deltoides Marsh under silvipastoral system in mid hills of Himachal Pradesh. Environment and Ecology, 17(1): 120-124. Chauhan, Rajani; Chauhan, S.K.; Khajuria, H.N. and Gera, M.K. 2000. Potential of exotic forest tree species in Punjab. Advances in Forestry Research in India, 23: 29-59. Chauhan, S.K.; Dhillon, W.S. and Nighat Jabeen. 2011. Analyzing the performance of Colocasia esculenta in poplar-based agroforestry system. APA News, 39: 9-10. Chauhan, S.K.; Sangeeta Rani and Ramesh Kumar. 2010. Assessing the economic viability of flower seed production under poplar trees. APA News, 37: 6-7 Chauhan, S.K.; Sharma, S.C.; Beri, V.; Ritu; Yadav, S. and Gupta, N. 2010. Yield and carbon sequestration potential of wheat (Triticum aestivum)-poplar (Populus deltoides) based agrisilvicultural system. Indian Journal of Agricultural Sciences, 80(2): 129-135. Chauhan, S.K.; Sharma, S.C.; Chauhan, R.; Gupta, Naveen and Ritu. 2010. Accounting poplar and wheat productivity for carbon sequestration in agrisilvicultural system. Indian Forester, 136(9): 11741182. Chauhan, V.K. and Dhiman, R.C. 2002. Evaluation of wheat (Triticum aestivum) under different spacing of poplar (Populus deltoides) in lower western Himalayas. Indian Journal of Agricultural Sciences, 72(8): 470-473. Chauhan, V.K. and Dhiman, R.C. 2003. Yield and quality of sugarcane under poplar (Populus deltoides)-based rainfed agroforestry. Indian Journal of Agricultural Sciences, 73(6): 343-344. Chaukiyal, S.P.; Shams, P.M. and Sagta, H.C. 2010. Evaluation of stool plant of Populus ciliata Wall. with respect to their growth and production of desired cutting at different spacing and cutback. Annals of Forestry, 18(2): 231-242. Dey, A.N. and Debata, D.K. 2000. Studies on leaf spot disease of Populus deltoides Marsh caused ENVIS 43. 44. 45. 46. 47. 48. 49. 50. 51. 52. 53. 54. by Alternaria raphani. Indian Forester, 126(9): 1013-1014. Dhanda, R.S. and Inderbir Kaur. 2000. Production of poplar (Populus deltoides Bartr.) in agri-silviculture system in Punjab. Indian Journal of Agroforestry, 2: 93-97. Dhanda, R.S. and Verma, R.K. 2001. Timber volume and weight tables of farm-grown poplar (Populus deltoides Bartr. ex Marsh.) in Punjab, (India). Indian Forester, 127(1): 115-130. Dhillon, Ashok; Sangwan, Vinod; Malik, D.P. and Luhach, M.S. 2001. An economic analysis of poplar cultivation. Indian Forester, 127(1): 86-90. Dhillon, G.P.S. and Sidhu, D.S. 2010. Variation for growth traits among 17 poplar (Populus deltoides Bartr.) clones planted in Punjab. Indian Forester, 136(6): 815-820. Dhillon, G.P.S.; Dhanda, R.S.; Gill, R.I.S. and Singh, Pritpal. 2011. Estimation of over- and under-size merchantable timber volume of Populus deltoides Bartr. Indian Forester, 137 (3): 356-362. Dhillon, G.P.S.; Sidhu, D.S. and Singh, Avtar. 2011. Field evaluation of Populus deltoides Bartr. clones in the central Punjab. Journal of Tropical Forestry, 27 (3): 26-31. Dhillon, G.P.S.; Singh, Avtar and Sidhu, D.S. 2010. Performance of poplar (Populus deltoides Bartr.) clones under semi-arid conditions of Punjab. Indian Journal of Forestry, 33(3): 309-311. Dhillon, G.P.S.; Singh, Avtar and Sidhu, D.S. 2010. Variation, inheritance and correlation of growth characteristics of Populus deltoides Bartr. at various ages in the central-plain region of Punjab, India. Forestry Studies in China, 12(3): 126-130. Dhillon, G.P.S.; Singh, Avtar; Singh, Pritpal and Sidhu, D.S. 2010. Field evaluation of Populus deltoides Bartr. ex Marsh, at two sites in Indo-Gangetic Plains of India. Silvae Genetica, 59(1): 1-7. Dhillon, W.S.; Chohan, S.K.; Singh, N.; Rattan, C.S. and Singh, D. 2010. Pre-bearing behaviour of some fruit crops under horti-silviculture system. Indian Journal of Horticulture, 67(3): 311-314. Dhillon, W.S.; Srinidhi, H.V.; Singh, Chaturjeet and Navjot. 2011. Integration of trees in orchards: Opportunities to increase tree cover in Punjab. Journal of Horticulture and Forestry, 3(5): 134-137. Dhiman, R.C. 2004. Damage of poplar nurseries and young field plantations by blue bull. Indian Forester, 130(4): 467-468. Forestry Bulletin, 12(1), 2012 55. 56. 57. 58. 59. 60. 61. 62. 63. 64. 65. 66. 67. Dhiman, R.C. 2011. Wildlife damage to poplar. Indian Forester, 137 (10): 1212-1216. Dhiman, R.C. and Gandhi, J.N. 2010. Field performance of traditionally propagated vis-a-vis tissue cultured poplar. Annals of Forestry, 18(2): 223-230. Dhiman, R.C. and Gandhi, J.N. 2010. Varietal differences in onion and garlic yield when grown with and without mulch in three years old poplar plantation. Indian Journal of Agroforestry, 12(1): 40-45. Dhiman, R.C.; Thapliyal, R.C. and Singh, Jagdish. 1997. One year field performance of three genetically controlled poplar clones with locally produced ETPs. Indian Journal of Forestry, 20(4): 398-400. Dhyani, S.K.; Ajit; Handa, A.K. and Nighat Jabeen; Uma. 2011. Agroforestry: An integrated system for conservation of natural resources in Northern India. Indian Journal of Forestry, 34 (2): 121-130. Dimri, M.P.; Shukla, K.S. and Sanjay Kumar. 1998. Effect of PF glue line treatment with chlorpyrifos on the glue shear strength and termite resistance in Populus deltoides plywood. Journal of the Timber Development Association of India, 44 (2): 36-42, 44. Dinesh Kumar and Singh, N.B. 2001. Age-age correlation for early selection of clones of Populus in India. Silvae Genetica, 50(3-4): 103-108. Dinesh Kumar; Pawan Kumar and Pradeep Kumar. 2001. Leaf fall in poplar and its impact on wheat intercrop. Indian Forester, 127(2): 187-190. Dinesh Kumar; Singh, N.B.; Rawat, G.S.; Srivastava, Shivendu and Dhananjay Mohan. 1999. Improvement of Populus deltoides Bartr. ex Marsh. in India - I. Present status. Indian Forester, 125(3): 245-263. Dobriyal, P.B.; Chauhan, K.S. and Indra Dev. 2001. The durability and treatability of Populus deltoides Marsh. Indian Forester, 127(2): 207-212. Dogra, A.S.; Chauhan, S.K.; Sharma, R.; Garg, R.K.; Singh, K. and Saralch, H.S. 2011. Contribution of trees outside forests toward wood production and environmental amelioration. Indian Journal of Ecology, 38(Special Issue): 1-5. Dubey, Y.M.; Gupta, Sachin and Shukla, N.K. 1997. Estimation of modulus of elasticity of Populus deltoides by vibration test method. Journal of the Timber Development Association of India, 43(4): 5-9. Faiz Mohsin and Babu Ram. 2002. Sixty-month study on litter production, changes in soil chemical 159 68. 69. 70. 71. 72. 73. 74. 75. 76. 77. 78. 79. 160 properties and productivity under poplar (Populus deltoides) intercropped with wheat. Indian Journal of Agroforestry, 4(2): 81-87. Faiz Mohsin; Singh, R.P. and Singh, K. 1999. Biomass distribution in Populus deltoides under agroforestry system. Indian Forester, 125(8): 794-798. Faiz Mohsin; Singh, R.P. and Singh, K. 1999. Magnitude of retranslocation of N, P, K in Populus deltoides intercropped with aromatic crop. Annals of Forestry, 7(2): 254-262. Gangoo, S.A. and Khurana, D.K. 2002. In vitro multiplication of poplars: effects of growth regulators and genotypes. Applied Biological Research, 4(12): 11-16. Gangoo, S.A.; Mir, M.A.; Khan, A.A. and Gul Zaffar. 2011. Study of variability in the cultivated clones of Populus nigra Linn. (black poplar) of Kashmir Valley. Indian Forester, 137(6): 704-717. Gangoo, S.A.; Mughal, A.H. and Makaya, A.S. 1997. Fertilizer response by two species of poplars on initial growth parameters. Indian Forester, 123(3): 240-244. Ganguli, Jayalaxmi; Chandrakar, Shilpa and Puri, Sunil. 2000. New defoliators recorded on poplar at Raipur. Insect Environment, 6(1): 6. Ganguli, Jayalaxmi; Chandrakar, Shilpa; Swamy, S.L. and Puri, S. 1999. Bionomics of the poplar defoliator, Clostera cupreata Butler (Lepidoptera: Notodontidae) at Raipur. Insect Environment, 5(1): 36-37. Ganguli, Jayalaxmi; Chandrakar, Shilpa; Swamy, S.L. and Puri, Sunil. 1999. Clostera cupreata Butler (Lepidoptera: Notodontidae): A pest of poplar at Raipur. Insect Environment, 5(1): 33. Gaur, Atimanav and Adholeya, Alok. 2000. Response of three vegetable crops to VAM fungal inoculation in nutrient deficient soils amended with organic matter. Symbiosis Rehovot, 29(1): 19-31. Gera, Neelu; Gera, Mohit and Bisht, N.S. 2011. Carbon sequestration potential of selected plantation interventions in Terai region of Uttarakhand. Indian Forester, 137 (3): 273-289. Ghimire, T.B. and Bana, O.P.S. 2011. Effect of fertility levels on mustard (Brassica juncea) seed yield, quality and economics under varying poplar (Populus deltoides) tree densities. Indian Journal of Agronomy, 56(4): 346-350. Gogate, M.G., Ghude, D.B. and Deshpande, M.D. 1997. Experimental entire transplant technique for teak. Indian Forester, 123(9): 793-800. 80. 81. 82. 83. 84. 85. 86. 87. 88. 89. 90. 91. 92. Gupta, A.K.; Khara, H.S. and Singh, S. 2001. Incidence of leaf spots of poplar in three agroclimatic zones of Punjab. Plant Diseasen Research, 16(1): 134-136. Gupta, A.K.; Kushwaha, K.P.S. and Singh, S. 2001. Evaluation of some fungicides against foliage pathogens of poplar. Annals of Plant Protection Sciences, 9(1): 150-152. Gupta, Atul; Seghal, R.N.; Panwa, Pankaj and Thakur, I.K. 2002. Selection of rust (Melampsora spp.) resistant trees of Populus ciliata in Himachal Pradesh. Indian Journal of Forestry, 25(1-2): 96-98. Gupta, M.K. 2011. Soil organic carbon pool under different land uses in Haridwar district of Uttarakhand. Indian Forester, 137(1): 105-112. Gupta, R.K.; Singh, Kadam; Dinesh Kumar; Srivastata, Y.K. and Singh, N.B. 2001. Flowering status of Populus deltoides clones in India. Indian Forester, 127(2): 249-251. Handa, A.K.; Thakur, Sanjeev and Khurana, D.K. 2000. Isozyme banding in Populus ciliata x maximowiczii hybrids. Indian Journal of Forestry, 23(1): 75-77. Handa, A.K.; Thakur, Sanjeev and Khurana, D.K. 2001. Isozyme banding pattern in the hybrids of Populus ciliata x maximowiczii. Indian Forester, 127(1): 107-110. Harsh, N.S.K. and Pramod Kumar 1997. Screening for resistance against set-rot and mortality in poplar cuttings. Indian Forester, 123(3): 262-263. Indra Dev and Chauhan, K.S. 2004. Preservation aspects of some plantation timbers. Journal of the Timber Development Association of India, 50(1-2): 53-60. Jain, Avinash and Bisht, Smita. 2002. Clonal variation in chemical and biochemical characteristics of Populus deltoides Marsh in India. Myforest, 38(4): 391-398. Jain, S.K. and Singh, P. 2000. Economic analysis of industrial agroforestry: poplar (Populus deltoides) in Uttar Pradesh (India). Agroforestry Systems, 49(3): 255-273. Jain, S.K. and Singh, Parmatma. 1999. Performance of intercrops in agroforestry system: The case of poplar (Populus deltoides) in Uttar Pradesh (India). Indian Forester, 125(2): 195-205. Jain, S.K. and Singh, Parmatma. 1999. Performance of intercrops in agroforestry system: The case of poplar (Populus deltoides) in Uttar Pradesh (India). Indian Forester, 125(2): 195-205. ENVIS 93. 94. 95. 96. 97. 98. 99. 100. 101. 102. 103. Jain, V.K. and Khanduri, A.K. 2003. Interclonal variation in strength properties of Populus deltoides from Haldwani (Uttaranchal). Indian Forester, 129(9): 1069-1076. Jala, Sudha and Goyal, Dinesh. 2010. ESP fly ash application effects on plant biomass and bioconcentration of micronutrients in nursery seedlings of Populus deltoides. In: 19th World Congress of Soil Science: Soil Solutions for a Changing World, Brisbane, 1-6 August 2010. Proceedings. Wien, International Union of Soil Sciences Symposium. pp. 53-56. Jha, K.K. and Yogesh Kumar. 2000. Interspecific hybridization in poplars and initial performance of hybrids in Tarai of Uttar Pradesh. Indian Journal of Forestry, 23(1): 1-11. Jha, M.N. and Gupta, M.K. 2003. Light intensity pattern under agroforestry system. Indian Forester, 129(5): 564-570. Joshi, C.S.; Singh, R.P. and Rao, P.B. 1999. Pattern of leaf litter decomposition in forest plantations of Tarai region in Uttar Pradesh, India. Tropical Ecology, 40(1): 99-108. Joshi, Manoj. 2004. Provenance related response of Himalayan poplar to nitrogen application in the nursery. Bionotes, 6(1): 16-17. Joshi, Manoj and Nayital, R.K. 2002. Effect of cutting thickness on rooting, shoot emergence and growth of Populus ciliata Wall. Ex.Royle provenances. Range Management and Agroforestry, 23(2): 144-148. Joshi, Mukesh; Bargali, Kiran and Bargali, S.S. 1997. Changes in physico-chemical properties and metabolic activity of soil in poplar plantations replacing natural broad-leaved forests in Kumaun Himalaya. Journal of Arid Environments, 35(1): 161169. Kalia, Shamila and Lall, R.B. 2000. Efficacy of three varietal toxins of Bacillus thuringiensis tested against some important forest insect pests of multipurpose forest tree species. Indian Forester, 126(1): 62-66. Kalia, Shamila and Semwal, D.P. 2011. Biology of Parasa vivida Walk=Latoia vivida Walk [Lepidoptera: Limacodidae] - on its new host Populus deltoides Bartr. from India. Indian Journal of Forestry, 34 (3): 317-320. Karia, B.G. 2001. Delignifications of Populus deltoides as related to age. Journal of the Timber Development Association of India, 47(3-4): 24-26. Forestry Bulletin, 12(1), 2012 104. 105. 106. 107. 108. 109. 110. 111. 112. 113. 114. 115. Karnatak, D.C.; Khanna, P. and Chandra, A. 2001. A report on the present status of poplar clones in India. Indian Journal of Forestry, 24(2): 171-176. Katiyar, R.S.; Balak Ram; Tewari, S.K. and Singh, C.P. 1999. Response of turmeric to nitrogen and phosphorus application under intercropping system with poplar on sodic soils. Journal of Medicinal and Aromatic Plant Sciences, 21(4): 937-939. Katiyar, S.R. 2011. Populus ciliata is an industrial tree in Uttarakhand. Journal of Non-Timber Forest Products, 18 (4): 277-280. Kaushal Kumar; Mall, M.K.; Uttam, S.K. and Awasthi, U.D. 2010. Productivity and economics of poplar (Populus deltoids) based agroforestry system under water stress condition of central Uttar Pradesh. Current Advances in Agricultural Sciences, 2(2): 91-93. Kaushal, R.; Verma, K.S. and Singh, K.N. 2003. Effect of Grewia optiva and Populus deltoides leachates on field crops. Allelopathy Journal, 11(2): 229-234. Kaushik, N. and Singh, Jagdev. 2001. Performance of pearl millet-wheat in poplar based agri-silviculture system in sandy soils of southern Haryana. Indian Journal of Agroforestry, 3(1): 51-54. Khan, P.A.; Mughal, A.H. and Khan, M.A. 2001. Allelopathic effects of leaf extract of Populus deltoides M. on germination and seedling growth of some vegetables. Range Management and Agroforestry, 2(2): 231-236. Khurana, D.K. and Mohanty, T.L. 2000. Identification of selected clones of Populus deltoides Marsh by qualitative morphological traits. Environment and Ecology, 18(4): 958-961. Kohli, R.K.; Singh, H.P. and Batish, D.R. 1997. Phytotoxic potential of Populus deltoides Bartr. ex Marsh. I. Comparative contribution of different parts. Indian Journal of Forestry, 20(3): 300-304. Kulkarni, N. 1998. Feeding deterrence of some plant extracts against poplar defoliator, Clostera cupreata Butler (Lepidoptera: Notodontidae). Insect Environment, 3(4): 98. Lodhiyal, L.S. and Lodhiyal, N. 1997. Aspects of productivity and nutrient cycling of poplar (Populus deltoides Marsh) plantation in the moist plain area of the Central Himalaya. Oecologia Montana, 5(12): 28-34. Lodhiyal, L.S. and Lodhiyal, Neelu 1997. Variation in biomass and net primary productivity in short 161 116. 117. 118. 119. 120. 121. 122. 123. 124. 125. 126. 162 rotation high density central Himalayan poplar plantations. Forest Ecology and Management, 98(2): 167-179. Lodhiyal, L.S. and Lodhiyal, Neelu. 1997. Nutrient cycling and nutrient use efficiency in short rotation, high density central Himalayan Tarai poplar plantations. Annals of Botany, 79(5): 517-527. Lodhiyal, L.S.; Lodhiyal, Neelu and Singh, S.K. 2002. Litter dynamics and nutrient return of poplar plantations in moist plain areas of Central Himalayas. Indian Forester, 128(11): 1183-1194. Lodhiyal, L.S.; Lodhiyal, Neelu; Singh, S.K. and Koshiyari, R.S. 2002. Forest floor biomass, litter fall and nutrient return through litters of high density poplar plantations in Tarai of Central Himalaya. Indian Journal of Forestry, 25(3-4): 291-303. Luna, R.K.; Thakur, N.S.; Vijay Kumar; Chauhan, S.K;, Sharma, R.; Garg, R.K.; Singh, K. and Saralch, H.S. 2011. Growth performance of twelve new clones of poplar in Punjab, India. Indian Journal of Ecology, 38(Special Issue): 107-109. Misra, P.N. and Tewari, S.K. 1999. On the performance of poplars (Populus deltoides) on marginal soils in northern India. Biomass and Bioenergy, 16(4): 257-262. Mitra, Aparajita and Pal, Amita. 2000. Isozyme analysis of Populus deltoides and a hybrid poplar for the evaluation of genetic stability in the culture regenerated plants. Journal of Tropical Forest Science, 12(4): 697-706. Mohammad Faisal and Mukhtar Ahmad 2011. Effect of different host plants on the development of Spilarctia obliqua Walk. (Lepidoptera: Arctiidae). Indian Forester, 137 (3): 380-386. Mohanty, T.L. and Khurana, D.K. 2000. Comparative growth performance of Populus ciliata, P. yunnanensis, P. alba, P. deltoides, hybrid of P. ciliata and hybrid of P. deltoides in nursery stage. Environment and Ecology, 18(2): 392-397. Mohanty, T.L. and Khurana, D.K. 2000. Morphological characterization of selected clones of Populus deltoides Marsh. Environment and Ecology, 18(4): 948-951. Mohanty, T.L. and Khurana, D.K. 2002. Phenological behaviour in selected clones of Populus ciliata x Populus maximowiczii hybrid. Journal of Interacademicia, 6(1): 37-40. Mughal, A.H. and Bhattacharya, P. 2002. Agroforestry systems practiced in Kashmir Valley 127. 128. 129. 130. 131. 132. 133. 134. 135. 136. of Jammu and Kashmir. Indian Forester, 128(8): 846852. Mukhtar Ahmad; Ahmad, M.J. and Mishra, R.K. 1997. Indigenous micro-hymenopteran parasitoid species associated with poplar defoliator, Clostera cupreata (Lepidoptera: Notodontidae). Annals of Forestry , 5(1): 26-34. Mukhtar Ahmad; Ahmad, M.J. and Mishra, R.K. 1999. Trichogramma poliae Nagaraja (Hymenoptera: Trichogrammatidae): A new record on poplar defoliator, Clostera cupreata (Lepidoptera: Notodontidae) from India: Its population dynamics and bio-efficacy. Annals of Forestry, 7(1): 9-19. Mukhtar Ahmad; Ahmad, M.J.; Mishra, R.K. and Sheel, S.K. 2001. Parasitization potential of the egg parasitoid, Telenomus colemani (Hymenoptera: Scelionidae), on the poplar defoliator, Clostera cupreata (Lepidoptera: Notodontidae). Journal of Tropical Forest Science, 13(2): 322-328. Mukhtar Ahmad; Ahmad, M.J.; Shama Afroze and Mishra, R.K. 2001. First record of coccinellid beetles (Coleoptera: Coccinellidae) on poplar, Populus deltoides from North India. Indian Forester, 127(8): 891-897. Mukhtar Ahmad; Mishra, R.K. and Jamal Ahmad. 2001. Insect pest spectrum of poplar in India. Indian Forester, 127(12): 1353-1366. Mukhtar Ahmad; Mishra, R.K.; Gupta, Hemant and Jamal Ahmad, M. 2002. New fungal disease of poplar defoliator, Clostera cupreata Butler (Lepidoptera: Notodontidae). Indian Journal of Forestry, 25(1-2): 79-81. Mukhtar Ahmad; Mishra, R.K.; Md. Jamal Ahmad and Pandey, Rajiv. 2002. Defoliation capability of poplar defoliator, Clostera cupreata Butler (Lepidoptera: Notodontidae). Indian Forester, 128(12): 1360-1366. Naithani, H.B.; Sumer Chandra and Mohinder Pal. 2001. Indian poplars with special reference to indigenous species. Indian Forester, 127(2): 230237. Naithani, Sushma; Trivedi, P.K. and Sane, P.V. 1997. Characterization of the orf31-petG gene cluster from the plastid genome of Populus deltoides. Biochemistry and Molecular Biology International, 43(2): 433-442. Naithani, Sushma; Trivedi, P.K.; Tuli, Rakesh and Sane, P.V. 1997. The psbE-F-L-J operon from chloroplast genome of Populus deltoides: Cloning, ENVIS 137. 138. 139. 140. 141. 142. 143. 144. 145. 146. 147. 148. nucleotide sequence and transcript analysis. Journal of Genetics, 76(1): 61-72. Nanda, Rakesh; Momi, G.S. and Chauhan, Sanjeev. 2001. Awareness of adopters and non-adopters towards different aspects of poplar based agroforestry in Punjab. Indian Forester, 127(2): 191198. Nandal, D.P.S.; Anil Kumar and Hooda, M.S. 1999. Performance of wheat varieties in association with eucalypt and poplar windbreaks and sissoo block plantation. Indian Journal of Forestry, 22(1-2): 73-77. Navneet Kaur; Singh, Baljit and Gill, R.I.S. 2010. Agrotechniques for increasing productivity of wheat (Triticum oestivum) under poplar (Populus deltoides) plantation. Indian Journal of Agronomy, 55(1): 68-74. Negi, M.S. and Tandon, V.N. 1997. Biomass and nutrient distribution in an age sequence of Populus deltoides ecosystems in Haryana. Indian Forester, 123(2): 111-117. Negi, M.S.; Rajagopal, J.; Chauhan, Neeti; Cronn, R. and Lakshmikumaran, Malathi. 2002. Length and sequence heterogeneity in 5S rDNA of Populus deltoides. Genome, 45(6): 1181-1188. Newman, S.M. 1997. Poplar agroforestry in India. Forest Ecology and Management, 90(1): 13-17. Nimkar, A.U. and Mohapatra, K.P. 2002. Three decades of research on properties and utilization of Populus deltoides – a review. Indian Forester, 128(11): 1254-1261. Pande, P.K. 2011. Variation in wood properties and growth in some clones of Populus deltoides Bartr. ex Marsh. American Journal of Plant Sciences, 2(5): 644-649. Pande, P.K. and Dhiman, R.C. 2010. Variations in wood traits in micro and macro propagated plantation woods of Populus deltoides Bartr. ex Marsh. Advances in Bioscience and Biotechnology, 1(4): 263-275. Pande, P.K. and Dhiman, R.C. 2011. Performance and variability patterns in wood properties and growth traits in the parents, F1 and F2 generation hybrid clones of Populus deltoides. Journal of Forestry Gupta Research, 22(3): 379-385. Pandey, Amit; Harsh, N.S.K. and Suresh Chandra. 2002. A new stem canker disease of poplar in Doon Valley. Indian Forester, 128(9): 1033-1036. Pandey, C.N. and Kambo, A.S. 2001. Properties and processing of Populus deltoides Bartr. for producing Forestry Bulletin, 12(1), 2012 149. 150. 151. 152. 153. 154. 155. 156. 157. 158. 159. 160. quality sawn and seasoned timber. Indian Forester, 127(2): 238-241. Pandey, Deepak; Pandey, Vasudha; Tripathi, Sanjay and Tewari, S.K. 1997. Path analysis in Populus deltoides Bart: 8 year age. Indian Forester, 123(8): 755-758. Pandey, Rajiv; Dhall, S.P.; Kanwar, B.S. and Bhardwaj, S.D. 1998. Some models for predicting volume of Populus deltoides. Indian Forester, 124(8): 629-632. Pandit, Atul; Pant, Kavita and Jeet Ram. 2002. Effect of collection date on capsule moisture content and germination of Populus ciliata Wall. ex Royle from central Himalaya. New Forests, 23(2): 121-130. Pannu, N.S. and Dhillon, M.S. 1999. Production potential of poplar-wheat based agroforestry system in relation to wheat varieties and their dates of sowing. Indian Journal of Forestry, 22(3): 257-262. Pant, A.K. and Bana, O.P.S. 1998. Crop productivity of wheat (Triticum aestivum L.) and urd (Phaseolus mungo (L.) Mant.) under plantation crops. Indian Journal of Forestry, 21(3): 238-241. Pant, A.K. and Singh, T.A. 1998. Water table and soil moisture distribution below some agroforestry tree species. Indian Journal of Forestry, 21(2): 119-123. Pant, K.S.; Mishra, V.K.; Sanwal, C.S. and Dinssa, K.U. 2010. Effect of nitrogen and poplar spacing on yield and nutrients content of taro (Colocasia esculenta L.). Indian Journal of Agroforestry, 12(1): 18-22. Pant, Kavita; Pandit, Atul; Tewari, Ashish and Koshyari, R.S. 1999. Agroforestry patterns in the Tarai region of central Himalaya. Indian Journal of Forestry, 22(1-2): 123-128. Panwar, V.P. and Sharma, Rajesh. 2001. Nursery performance of exotic Poplars under mid-hill conditions of Himachal Pradesh. Indian Forester, 127(1): 44-50. Pathre, Uday; Sinha, A.K.; Shirke, P.A. and Sane, P.V. 1998. Factors determining the midday depression of photosynthesis in trees under monsoon climate. Trees: Structure and Function, 12(8): 472-481. Piare Lal. 2010. Clonal forestry in India. Indian Forester, 136(1): 17-37. Poonam, D.N.; Bawa, Rajan; Tara; Chauhan, S.K.; Sharma, R.; Garg, R.K.; Singh, K. and Sarah, H.S. 2011. Agroforestry systems of Lahaul and Spiti District of Himachal Pradesh, Western Himalaya. Indian Journal of Ecology, 38(Special Issue): 129-131. 163 161. 162. 163. 164. 165. 166. 167. 168. 169. 170. 171. 172. 164 Puri, S. and Nair, P.K.R. 2004. Agroforestry research for development in India: 25 years of experiences of a national program. Agroforestry Systems, 61-62: 437452. Puri, S.; Swamy, S.L. and Jaiswal, A.K. 2002. Evaluation of Populus deltoides clones under nursery, field and agrisilviculture system in subhumid tropics of Central India. New Forests, 23(1): 45-61. Puri, Sunil. 2002. Estimation of aerial biomass of Populus deltoides clones growing in agricultural fields. Range Management and Agroforestry, 23(2): 99-104. Puri, Sunil and Sharma, Amita. 2002. Productivity of wheat under a Populus deltoides agroforestry system in the south-east of Central India. Indian Forester, 128(12): 1319-1326. Puri, Sunil and Thompson, F.B. 2003. Effect of soil and plant water relations on rooting of Populus x euramericana stem cuttings. New Forests, 25(2): 109-124. Puri, Sunil and Thompson, F.B. 2003. Relationship of water to adventitious rooting in stem cuttings of Populus species. Agroforestry Systems, 58(1): 1-9. Puri, Sunil; Swamy, S.L. and Jaiswal, A.K. 2001. The potential of Populus deltoides in the sub-humid tropics of Central India: Survival, growth and productivity. Indian Forester, 127(2): 173-186. Raina, Ranjit; Hara, S.S.; Hara, V.; and Irland, L.C. 2011. Twenty-first century forest plantations: Development of agroforestry in Haryana. Journal of Resources, Energy, and Development, 8(2): 67-74. Raj, A.J.; Lal, S.B.; Daniel, Sameer and Gowda, Vitala. 2010. Intercropping of lemon grass with poplar (Populus deltoide Bartr. ex Marsh) in Eastern Uttar Pradesh. Indian Journal of Agroforestry, 12(1): 1317. Rajagopal, J.; Bashyam, L.; Bhatia, S.; Khurana, D.K.; Srivastava, P.S. and Lakshmikumaran, M. 2000. Evaluation of genetic diversity in the Himalayan poplar using RAPD markers. Silvae Genetica, 49(2): 60-66. Rajiv Kumar; Gupta, P.K. and Gulati, Ajay. 2004. Viable agroforestry models and their economics in Yamunanagar District of Haryana and Haridwar District of Uttaranchal. Indian Forester, 130(2): 131148. Rajput, S.S.; Shukla, N.K. and Khanduri, A.K. 1997. Studies on variation of specific gravity and 173. 174. 175. 176. 177. 178. 179. 180. 181. 182. 183. 184. compressive strength of different clones of Populus deltoides. Van Vigyan, 35(3-4): 165-171. Rakesh Kumar. 2004. Effect of spacing on growth of nursery plants in Populus deltoides under flood plain zone of Punjab. Annals of Agri-Bio Research, 9(1): 43-45. Rakesh Kumar. 2004. Performance of Populus deltoides under agroforestry and sole planting situations in flood-plains of Punjab. Environment and Ecology, 22(3): 487-489. Ramesh, K.R. and Khurana, D.K. 2003. Natural provenance variation in Populus alba Linn. from Western Himalaya. Indian Forester, 129(9): 1077-1084. Rameshwar Dayal and Dobhal, P.C. 2000. Dye from poplar bark. Indian Textile Journal, 110(7): 60-63. Ran, R.K. and Kaushal, P. 2004. Economic analysis of plantations in water-logged soils - a case study of Suan River of District Una (H.P.). Economic Affairs Calcutta, 49(2): 98-103. Rana, B.S.; Saxena, A.K. and Verma, S.K. 2011. Agroforestry research on sodic wasteland in eastern part of Uttar Pradesh. Indian Forester, 137(12): 14101422. Rawat, G.S.; Singh, N.B.; Gupta, R.K.; Singh, K. and Sharma, S.D. 2001. Clonal evaluation of poplar (Populus deltoides Bartr.) in eastern Uttar Pradesh. I - Nursery testing. Indian Forester, 127(1): 70-80. Ray, S.N. and Khan, M.A. 2002. Time span of sucking and per cent consumption of poplar defoliator, Clostera fulgurita Walk. by Sycanus collaris Fabr. (Hemiptera: Reduviidae). Shashpa, 9(1): 53-55. Reddy, M.S. and Satyanarayana, T. 1998. Ectomycorrhizal formation in micropropagated plantlets of Populus deltoides. Symbiosis Rehovot, 25(1-3): 343-348. Reddy, M.S.S.; Naithani, Sushma; Tuli, R. and Sane, P.V. 2000. Diurnal regulation of plastid genes in Populus deltoides. Indian Journal of Biochemistry and Biophysics, 37(6): 453-458. Reddy, M.S.S.; Trivedi, P.K.; Tuli, Rakesh and Sane, P.V. 1997. Expression of chloroplastic genes during autumnal senescence in a deciduous tree Populus deltoides. Biochemistry and Molecular Biology International, 43(3): 677-684. Rizvi, R.H.; Dhyani, S.K. and Maurya, Deepak. 2011. Models for estimating carbon stock in stem wood biomass of poplar trees in agroforestry plantations in Tarai plains of North-Western India. Indian Journal of Forestry, 34 (3): 253-256. ENVIS 185. 186. 187. 188. 189. 190. 191. 192. 193. 194. 195. 196. Rizvi, R.H.; Dhyani, S.K.; Yadav, R.S. and Singh, Ramesh. 2011. Biomass production and carbon stock of poplar agroforestry systems in Yamunanagar and Saharanpur districts of northwestern India. Current Science, 100(5): 736-742. Rizvi, R.H.; Khare, Diwaka and Handa, A.K. 2010. Construction and validation of models for timber volume of poplar (Populus deltoides) planted in agroforestry in Haryana. Indian Journal of Agricultural Sciences, 80(9): 841-844. Roychoudhury, N.; Joshi, K.C. and Rawat, P.S. 2001. Phalantha phalantha Drury (Lepidoptera: Nymphalidae) - a major nursery pest of poplar, Populus deltoides Bartr. Indian Forester, 127(2): 252-254. Sagar, Mamta. 2010. Promoter analysis of an unknown gene in Populus trichocarpa x Populus deltoides, exposed to Malacosoma disstria Hubner. Asian Journal of Bio Science, 5(2): 200-205. Sagwal, S.S. 1999. Spatial arrangement for nursery plants of Populus alba Linn. Advances in Horticulture and Forestry, 7: 211-214. Sangha, K.S. 2011. Evaluation of management tools for the control of poplar leaf defoliators (Lepidoptera: notodontidae) in northwestern India. Journal of Forestry Research, 22(1): 77-82. Sangha, K.S. and Singh, Gurmail. 2011. Field evaluation of insecticides against two key leaf defoliators of poplar. Annals of Plant Protection Sciences, 19(2): 369-371. Sangha, K.S.; Shera, P.S.; Singh, Gurmail; Chauhan, S.K.; Sharma, R.; Garg, R.K.; Singh, K. and Saralch, H.S. 2011. Clostera resitura (Walker) larval behaviour on poplar (Populus deltoides) clones. Indian Journal of Ecology, 38(Special Issue): 178-182. Santosh Kumar; Gaur, G.S. and Ram Pyare. 2003. Economy of poplar based agro-forestry system in different agro-ecological regions of U.P. Progressive Agriculture, 3(1-2): 18-21. Sardana, P.K.; Parry, W.H. and Slee, R.W. 2000. Farm household level planning model for agroforestry in Haryana, India. International Tree Crops-Journal, 10(3): 177-192. Sarma, T.C. 2000. Poplar – its culture and use as a source of raw material for pulp and paper industry. Advances in Forestry Research in India, 22: 1-23. Satish Kumar. 1997. Strategies for sustainable wood supplies in the changing Indian scenario. Journal Forestry Bulletin, 12(1), 2012 197. 198. 199. 200. 201. 202. 203. 204. 205. 206. 207. of the Timber Development Association of India, 43(3): 5-13. Satish Kumar; Ravi Kumar and Neeraj Kumar. 2011. Effect of spacing on biomass production, nutrient content and uptake by poplar (Populus deltoides) plantations. Indian Journal of Forestry, 34 (2): 157160. Satish Kumar; Ravi Kumar; Neeraj Kumar and Singh, Rajendra. 2011. Effect of spacing on biomass production, nutrient content and uptake by poplar (Populus deltoides) plantations. Indian Forester, 137(7): 889-894. Sharma, A.; Dwivedi, B.N.; Singh, B. and Kumar, K. 1999. Introduction of Populus euphratica in Indian semi-arid trans-Gangetic plains. Annals of Forestry, 7(1): 1-8. Sharma, Amita; Puri, Sunil and Sharma, Rajnish. 2002. Performance of Populus deltoides clones in Chhattisgarh region. Range Management and Agroforestry, 23(1): 75-76. Sharma, Jaipal and Khurana, D.K. 2011. Morphological variation of poplar clones under subtropical and sub-temperate conditions. Indian Journal of Forestry, 34 (1): 79-84. Sharma, N.K. and Dadhwal, K.S. 2011. Growth behavior of irrigated wheat as influenced by annual growth cycle of Populus deltoides M. plantations in alluvial soil. Indian Journal of Soil Conservation, 39(1): 67-72. Sharma, N.K.; Samra, J.S. and Singh, H.P. 2000. Effect of aqueous extracts of Populus deltoides M. on germination and seedling growth. 1. Wheat. Allelopathy Journal, 7(1): 56-68. Sharma, N.K.; Samra, J.S. and Singh, H.P. 2000. Effect of leaf litter of poplar on Phalaris minor weed. Allelopathy Journal, 7(2): 243-253. Sharma, N.K.; Samra, J.S. and Singh, H.P. 2001. Influence of boundary plantation of poplar (Populus deltoides M.) on soil - water use and water use efficiency of wheat. Agricultural Water Management, 51(3): 173-185. Sharma, N.K.; Samra, J.S. and Singh, H.P. 2001. Poplar (Populus deltoides) based agroforestry systems for an alluvial soil under irrigated condition in western Uttar Pradesh. Indian Forester, 127(1): 61-69. Sharma, N.K.; Singh, H.P. and Dadhwal, K.S. 2000. Effect of poplar (Populus deltoides) on wheat growth at an early stage. Indian Journal of Soil Conservation, 28(3): 221-225. 165 208. 209. 210. 211. 212. 213. 214. 215. 216. 217. 218. 219. 220. 166 Sharma, N.K.; Singh, H.P. and Dadhwal, K.S. 2000. Nutrient returns through litter fall in Populus deltoides based agroforestry system. Indian Forester, 126(3): 295-299. Sharma, N.K.; Singh, H.P. and Dadhwal, K.S. 2002. Effect of poplar (Populus deltoides M.) plantation on weed growth in wheat crop. Indian Journal of Agroforestry, 4(2): 104-108. Sharma, R.C. and Sharma, Sanjeev. 1999. Effect of fungicides on the development of Cladosporium leaf spot of poplar in Western Himalaya. Acta Phytopathologica et Entomologica Hungarica, 34(1-2): 57-62. Sharma, R.C. and Sharma, Sanjeev. 2000. Status and distribution of foliar diseases of poplar in Himachal Pradesh. Indian Phytopathology, 53(1): 57-60. Sharma, R.C. and Sharma, Sanjeev. 2001. Reaction of poplar germplasm to Cladosporium leaf spot. Indian Forester, 127(2): 160-162. Sharma, R.C.; Khan, Y. and Gupta, AK. 2002. Development of Melampsora leaf rust in nursery grown Populus ciliata. Indian Forester, 128(8): 926-930. Sharma, R.C.; Khan, Y.; Sharma, S. and Malhotra, R. 2001. Development of Melampsora ciliata rust on nursery-grown poplars in north-western Himalayas. Forest Pathology, 31(5): 313-319. Sharma, R.C.; Sharma, Sanjeev and Gupta, A.K. 1999. Poplar diseases and their management in nurseries and plantations. Advances in Forestry Research in India, 20: 211-227. Sharma, R.C.; Sharma, Sanjeev and Gupta, A.K. 2001. Stomatal characters of Populus ciliata in relation to leaf rust and growth parameters. Phytomorphology, 51(2): 199-205. Sharma, R.C.; Sharma, Sanjeev and Khurana, D.K. 1999. Assessment of poplar germplasm for resistance against Alternaria alternata causing leaf spot of poplars in Himachal Pradesh. Indian Forester, 125(8): 784-787. Sharma, S. and Sharma, R.C. 2004. Relationship between leaf flushing time and initiation of leaf rust in poplar. Journal of Tropical Forest Science, 16(3): 369-372. Sharma, S.K.; Chauhan, S.K. and Handa, A.K. 1998. Wheat based agroforestry system under rainfed ecosystem. Range Management and Agroforestry, 19(1): 43-48. Sharma, S.K.; Chauhan, Sudhir; Sharma, S.K.; Baljinder Kaur and Arya, I.D. 2010. Opportunities 221. 222. 223. 224. 225. 226. 227. 228. 229. 230. 231. and major constraints in agroforestry systems of Western U.P: A vital role of Star Paper Mills, Saharanpur (UP) India. Agriculture and Biology Journal of North America, 1(3): 343-349. Sharma, Sandeep; Rawat, P.S.; Gera, Mohit and Pant, N.C. 1998. Leaf-shedding and emergence pattern in five clones of Populus deltoides Marsh under central Indian conditions. Indian Forester, 124(12): 1025-1031. Sharma, Sanjeev and Sharma, R.C. 2001. Epidemiology of Melampsora ciliata leaf rust of poplars in India. Zeitschrift fur Pflanzenkrankheiten und Pflanzenschutz, 108(4): 337-344. Sharma, Sanjeev and Sharma, R.C. 2002. Prevalence of poplar leaf rust in Himachal Pradesh. Indian Phytopathology, 55(1): 81-83. Sharma, Sanjeev and Sharma, R.C. 2003. Influence of host genotype and pathogen isolate in the development of poplar leaf rust. Zeitschrift fur Pflanzenkrankheiten und Pflanzenschutz, 110(4): 359-365. Sharma, Sanjeev; Sharma, R.C. and Sharma, J.N. 2001. Morphological variability in Melampsora ciliata the incitant of poplar leaf rust. Indian Forester, 127(2): 242-248. Sharma, V.K., Sharma, S.K. and Rawat, M.S. 1999. Sex reversal in Populus gamblei Dode following grafting. Indian Forester, 125(5): 533-535. Shujauddin and Khan, H.R. 1999. New record of damage to poplar due to Leucoptera sphenograpta Meyrick (Lepidoptera: Lyonetiidae), a leaf miner on poplar in Uttar Pradesh. Indian Forester, 125(12): 1255-1260. Shukla, K.S.; Negi, Anil and Ramesh Chandra. 1997. Properties of laminated veneer lumber (LVL) from Populus deltoides treated with copper-chromearsenic (CCA) preservative. Journal of the Timber Development Association of India, 43(1): 39-43. Shukla, N.K.; Khanduri, A.K. and Dangwal, M.N. 2000. Physical and mechanical properties of different clones of Populus deltoides - an assessment. Indian Forester, 126(1): 31-56. Singh, A.P. 1998. Sycanus collaris Fabr. (Reduviidae: Hemiptera), a new predator of Clostera spp. on Populus deltoides [in Uttar Pradesh]. Indian Forester, 124(2): 172. Singh, A.P. 2000. Relative natural resistance of Populus deltoides clones against defoliator Clostera cupreata (Lepidoptera: Notodontidae) in northern India. Agroforestry Systems, 49(3): 319-326. ENVIS 232. 233. 234. 235. 236. 237. 238. 239. 240. 241. 242. 243. Singh, A.P. 2002. Relative natural resistance of newly introduced Populus deltoides clones in India against defoliator Clostera cupreata. Indian Forester, 128(3): 307-312. Singh, A.P. and Mukhtar Ahmed. 2001. Seasonal variation in adult longevity of Aleoides percurrens Lyle (Hymenoptera: Braconidae), a larval parasitoid of poplar defoliator Clostera cupreata Butler. Indian Forester, 127(1): 81-85. Singh, A.P. and Pandey, R. 2002. Natural resistance of Populus deltoides clones selection to defoliator Clostera cupreata (Lep., Notodontidae) in northern India: Relative pupal weight as an easier criteria for accurate evaluation. Journal of Applied Entomology, 126(9): 475-480. Singh, A.P. and Pandey, Rajiv. 2000. Natural resistance in Populus deltoides clones against the defoliator Clostera cupreata in North-Western India - I. IndianForester, 126(6): 619-624. Singh, Bajrang 1998. Biomass production and nutrient dynamics in three clones of Populus deltoides planted on IndoGangetic plains. Plant and Soil, 203(1): 15-26. Singh, Bajrang 1998. Productivity dynamics of Populus deltoides clones on a degraded Gangeticalluvium in north India. Journal of Tropical Forest Science, 10(4): 478-493. Singh, Bajrang and Behl, H.M. 1999. Energy flow, carbon and nitrogen cycling in Populus deltoides clones in north India. Biomass and Bioenergy, 17(4): 345-356. Singh, Bajrang and Behl, H.M. 2001. Scope of Populus deltoides on marginal lands of IndoGangetic plains. Indian Forester, 127(1): 91-100. Singh, Baljit. 2001. Influence of fertilization and spacing on growth and nutrient uptake in poplar (Populus deltoides) nursery. Indian Forester, 127(1): 111-114. Singh, Charan. 1998. Natural resistance in poplar against Eucosma glaciata, Meyrick (Lepidoptera: Eucosmidae). Indian Journal of Forestry, 21(4): 316320. Singh, Charan and Devagiri, G.M. 1997. Analysis of variability in morphological traits in Populus ciliata Wall. ex Royle provenances. Indian Journal of Soil Conservation, 25(3): 219-221. Singh, D.R.R. and Jhajaria, V.K. 2001. Evaluation of credit worthiness for institutional financing through growth of Populus deltoides Marsh grown in forest Forestry Bulletin, 12(1), 2012 244. 245. 246. 247. 248. 249. 250. 251. 252. 253. 254. site and farm forestry. Indian Forester, 127(12): 13111325. Singh, D.R.R. and Vashista, U.S. 2001. Economic viability of raising entire-rooted transplants (ETPs) of Populus deltoides Marsh., in nursery and effect of economies of scale. Indian Forester, 127(1): 1115. Singh, Dipak; Chandra, J.P. and Singh, A.B. 1999. Response of fungicides and antibiotics against anthracnose of poplar caused by Colletotrichum graminicolum. Indian Forester, 125(6): 566-572. Singh, Gurbachan; Singh, Harinder and Singh, Jaspal. 1997. Effects of Populus deltoides litter on its saplings, associated agricultural crops and the properties of an alkali soil. Journal of Tropical Forest Science, 9(4): 536-545. Singh, H.P.; Kohli, R.K. and Batish, D.R. 1998. Effect of poplar (Populus deltoides) shelterbelt on the growth and yield of wheat in Punjab, India. Agroforestry Systems, 40(2): 207-213. Singh, H.P.; Kohli, R.K. and Batish, D.R. 1999. Impact of Populus deltoides and Dalbergia sissoo shelterbelts on wheat – a comparative study. International Tree Crops Journal, 10(1): 51-60. Singh, H.P.; Kohli, R.K. and Batish, D.R. 2001. Allelopathic interference of Populus deltoides with some winter season crops. Agronomie, 21(2): 139146. Singh, Harpal; Sharma, N.K. and Tomar, H.P.S. 2003. Effect of boundary plantation of poplar (Populus deltoides M.) on growth and yield of rice. Indian Journal of Soil Conservation, 31(3): 318-320. Singh, Jagdish and Dhiman, R.C. 1999. Effect of weed control on the growth of Populus deltoides G3 at nursery stage. Indian Forester, 125(8): 803-806. Singh, K.P. 2011. Efficacy of monocrotophos and dimethoate against poplar shoot borer Eucosma glaciata Meyrick (Lepidoptera: Eucosmidae). Annals of Forestry, 19(2): 245-248. Singh, N.B.; Dinesh Kumar and Gupta, R.K. 2001. Future of poplars in India. In: International Symposium on Tropical Forestry Research: Challenges in the New Millennium, Peechi, 2-4 August 2000. Proceedings. Peechi,, Kerala Forest Research Institute. pp. 91-98. Singh, N.B.; Dinesh Kumar; Gupta, R.K. and Singh, K. 2001. Poplar improvement: need, implementation and achievement. Advances in Horticulture and Forestry, 8: 205-237. 167 255. 256. 257. 258. 259. 260. 261. 262. 263. 264. 265. 266. 168 Singh, N.B.; Dinesh Kumar; Gupta, R.K.; Singh, Kadam and Khan, G.H. 2001. Role of poplar in sustainable development of India. Indian Journal of Agroforestry, 3(2): 92-99. Singh, N.B.; Dinesh Kumar; Rawat, G.S. and Gupta, R.K. 2001. Establishment of breeding orchard of Populus deltoides Bartr. Indian Forester, 127(1): 3-10. Singh, N.B.; Dinesh Kumar; Rawat, G.S. and Shrivastava, S.K. 1999. Improvement of Populus deltoides Bartr. ex Marsh. in India - II. Future strategy. Indian Forester, 125(4): 341-354. Singh, N.B.; Dinesh Kumar; Rawat, G.S.; Gupta, R.K.; Singh, K. and Negi, S.S. 2001. Clonal evaluation on poplar (Populus deltoides Bartr.) in Eastern Uttar Pradesh. II - Estimates of genetic parameters in field testing. Indian Forester, 127(2): 163-172. Singh, N.B.; Gupta, R.K. and Singh, K. 2001. Poplar (Populus deltoides Bart. ex-Marsh) in agroforestry: present status and future thrust. Advances in Horticulture and Forestry, 8: 247-264. Singh, N.V.; Sharma, R.C. and Chhimwal, C.B. 1999. Evolution of genetically superior new clones of poplar (Populus deltoides) for Tarai region. Indian Forester, 125(3): 301-304. Singh, Narendra; Singh, Gursharan; Amod Kumar and Stobden, T. 2010. Studies on afforestation for controlling avalanche and improving eco-environment in high altitude. Indian Forester, 136(9): 1254-1260. Singh, Rajpal and Verma, T.D. 1998. Incidence and control of poplar stem borer, Apriona cinerea, Chevrolet (Cerambycidae: Coleoptera) in Paonta Valley of Himachal Pradesh. Indian Forester, 124(7): 556-560. Singh, Ravinder; Sohi, A.S. and Sangha, K.S. 2001. Brachymeria species (Hymenoptera : Chalcididae) a larval pupal parasitoid of Asphadastis cryphomycha Meyrick, poplar leaf webber in Punjab. Indian Forester, 127(1): 133-134. Singh, Ravinder; Sohi, A.S. and Sangha, K.S. 2001. Studies on seasonal history, host range and nature of damage caused by Asphadastis cryphomycha Meyrick (Lepidoptera: Pyralidae) on poplar in Punjab. Indian Journal of Forestry, 24(3): 357-361. Singh, S.P. and Negi, Anil. 2001. Utilisation of Poplar for wood composites. Indian Forester, 127(2): 154159. Singh, S.V. 2000. Prospects of pulp and papermaking from poplars. Journal of the Timber Development Association of India, 46(1-2): 23-26. 267. 268. 269. 270. 271. 272. 273. 274. 275. 276. 277. 278. 279. Singh, T.P. 2003. Potential of farm forestry in carbon sequestration. Indian Forester, 129(7): 839-843. Singh, V.N. and Upadhyay, A.K. 2001. Volume tables for G48 and D121 clones of Populus deltoides for the Tarai and Bhabhar region of Uttaranchal. Indian Forester, 127(1): 21-29. Srivastava, N.; Singh, B. and Behl, H.M. 2004. Nutrient status of Populus deltoides and Terminalia arjuna raised on sodic land. Journal of Tropical Forest Science, 16(2): 199-205. Srivastava, S.; Trivedi, P.K. and Nath, P. 2004. Irradiation-regulated differential accumulation of chloroplast-encoded transcripts in mature leaves of Populus deltoides. Photosynthetica, 42(2): 299-301. Srivastava, Sandhya; Trivedi, P.K. and Pravendra Nath. 2004. Components involved in RNA-protein interaction at the 3' untranslated region of rbcL mRNA of Populus deltoides. Plant Science, 167(4): 765-772. Sukla Chanda; Pramanik, A. and Maiti, G.G. 2010. Taxonomic study of the section Tacamahaca Spach of the genus Populus L. (Salicaceae Mirb.) in India. Indian Journal of Forestry, 33(3): 425-428. Sukla Chanda; Pramanik, A. and Maiti, G.G. 2011. Taxonomic account of the Indian Populus L. (Salicaceae Mirb.) with special emphasis on their distribution and identification. Indian Forester, 137(7): 872-876. Tewari, P.K. and Namgail, T. 1999. Biology of Trabala vishnou (Lefebvre) (Lepidoptera: Lasiocampidae) on Populus Linn. Indian Journal of Forestry, 22(4): 348350. Tewatia, B.S. and Khirwar, S.S. 2002. Utilization of green poplar (Populus deltoides) leaves in ration of Murrah buffalo calves. Indian Journal of Animal Nutrition, 19(4): 324-328. Thakur, M.L. 1999. Insect pest status of poplars in India. Indian Forester, 125(9): 866-872. Thakur, P.S.; Dutt, V.; Thakur, A. and Raina, R. 2010. Poplar based agroforestry systems: intercropping of medicinal herbs for better production and diversification. Indian Journal of Agroforestry, 12(1): 77-83. Thakur, R.K. and Rakesh Kumar. 2010. Poplar rust spores (Melamospora ciliata) as bee forage. Insect Environment, 15(4): 169. Trivedi, P.K.; Pravendra Nath and Sane, P.V. 1997. Photoinhibition of photosynthesis without net loss of photosystem II components in ENVIS 280. 281. 282. 283. 284. 285. 286. 287. 288. Populus deltoides. Journal of Biosciences, 22(3): 345-355. Ujjaini, M.M.; Tiwari, S.K. and Agrawal, A.P. 1998. Factors influencing vegetative propagation of Populus deltoides clone. Vaniki Sandesh, 22(4): 46. Uniyal, A.K.; Bagwari, H.K. and Todaria, N.P. 2003. Rehabilitation of abandoned and denuded lands in Garhwal Himalaya through afforestation techniques – a case study. Indian Journal of Soil Conservation, 31(3): 269-275. Uniyal, Kamla. 2001. A new species of Mycosphaerella on Populus deltoides from India. Indian Forester, 127(1): 131-132. Uniyal, Kamla. 2003. Arbuscular mycorrhizal association of Populus deltoides. Indian Forester, 129(4): 527-530. Uniyal, Kamla and Singh, Ajab. 2002. Set rot in Populus deltoides and its control. Indian Forester, 128(5): 589-591. Uniyal, Kamla; Singh, Ajab and Pandey, Rajiv. 2001. Leaf blight of poplar and its control. Indian Forester, 127(12): 1394-1396. Veluthakkal, Radha and Dasgupta, M.G. 2010. Pathogenesis-related genes and proteins in forest tree species. Trees: Structure and Function, 24(6): 993-1006. Verma, A.K.; Chaudhary, U.; Rakesh Kumar; Pant, A.K.; Gaur, A.K. and Lakhchaura, B.D. 2000. Anthocyanin, bisabolol and phenylammonialyase activity in cell cultures of Populus deltoides. Indian Journal of Experimental Biology, 38(10): 1050-1053. Verma, R.C. and Bangarwa, K.S. 2003. Performance of Populus deltoides clones under nursery Forestry Bulletin, 12(1), 2012 289. 290. 291. 292. 293. 294. 295. 296. conditions in arid climate of NW India. Range Management and Agroforestry, 24(2): 174-176. Vinod Kumar and Rajput, P.R. 2003. Studies on yield and yield components of wheat varieties in open and under poplar (Populus deltoides Bartr. Ex. Marsh) based agro-silviculture system. Plant Archives, 3(2): 183-189. Walia, Rajani. 2010. Entomopathogenic fungusNomuraea rileyi (Farlow) Samson for the control of Clostera cupreata Butler on Populus deltoides Bartr. Indian Forester, 136(11): 1564-1566. Yadav Rakesh; Arora, Pooja; Sandeep Kumar and Chaudhury, Ashok. 2010. Perspectives for genetic engineering of poplars for enhanced phytoremediation abilities. Ecotoxicology, 19(8): 1574-1588. Yadava, A.K. 1999. Effect of spacings and fertility levels on lemon grass (Cymbopogon flexuosus) under poplar based agroforestry system. Advances in Forestry Research in India, 20 70-85. Yadava, A.K. 1999. Suitability of medicinal and aromatic plants under poplar based agroforestry system. Advances in Plant Science Research in India, 10: 1-6. Yadava, A.K. 2001. Cultivation of lemon grass (Cymbopogon flexuosus, ‘CKP-25’) under poplar based agroforestry system. Indian Forester, 127(2): 213-223. Yadava, A.K. 2010. Biomass production and carbon sequestration in different agroforestry systems in Tarai Region of Central Himalaya. Indian Forester, 136(2): 234-244. Yasmeen and Kauser Jahan. 1998. Soil mycoflora of Populus deltoides. Annals of Forestry, 6(2): 196199. z 169 INSTRUCTIONS FOR CONTRIBUTORS Scope: ENVIS Forestry Bulletin intends to provide a vehicle for formal publication for scientific and technical contributions, reviews, popular articles, suitably argued opinions, short communications, news items and photographs on topics related to all aspects of forestry. It is a condition of submission of original contribution that they have not been submitted elsewhere for publication. The contributions should be in English language. Criteria for the asessment of contributions centre on the suitability of the topic for publication, technical quality of the work, clarity and conciseness of presentation and suitability of the material for printing. Manuscripts: Three copies should be submitted. They should be typed with double spacing on one side of good quality paper, leaving margins of about 38 mm at the left hand side and at the top and bottom of each sheet. Each copy should include a complete set of illustrations. Title should be short and contain words useful for indexing and information retrieval. Illustrations: Tables and illustrations should be comprehensible without reference to the text. Figures should be numbered consecutively with Indo-Arabic numerals. Original illustrations should not exceed 210 mm × 300 mm. Individual photographs forming a plate should be of high quality on full gloss paper, with full range of tones and good contrast. References: References cited in the text will be referred to by the name(s) of the author(s) with the year of publication in parenthesis. Consecutive citations in the text are placed in chronological order and seperated by semicolon. If there are more than two authors, only the senior author’s name is given, and this is followed by the phrase et al. References should be listed alphabetically at the end of the article conforming to the following usage: Journal: Dean, T.J. 2001. Potential effect of stand structure on belowground allocation. Forest Science, 47(1): 69-76. Simple book: Thomas, P. 2000. Trees: Their natural history. Cambridge, Cambridge University Press. 286 p. Contribution to composite book: Yeh, Francis C. 2000. Population genetics. In: Young, A.; Boshier, D. and Boyle, T. Eds. Forest conservation genetics: Principles and practice. Collingwood, CSIRO. pp. 21-37. Conference/workshop/seminar proceedings/papers: National Workshop on Rattans (Canes), Banglore, 4-5 February 1999. 1999. Proceedings. Bangalore, Bamboo Society of India. 106p. Contribution to conference/workshop/seminar proceedings/papers: Rajendran, S. 1999. Leading issues in rattan management in Karnataka. In: National Workshop on Rattans (Canes), Bangalore, 4-5 February 1999. Proceedings. Bangalore, Bamboo Society of India. pp. 25-27. Thesis: Upadhyay, A. 1987. Transposon induced mutagenesis in Bacillus brevis AG 4. M.Sc. thesis. G.B. Pant University of Agriculture and Technology, Pantnagar. 214 p. ‘gs gs o`{kk’ gs o`{k fouez] fo”kky] euh"kh! fojDr ekuks ,d riLoh] dsoy nsuk tkuk rqeus] ugha dHkh dqN ek¡xk rqeusA thou thuk dsoy ijfgr] uUgsa cht esa fNik vfLrRoA l``f"V dh rqe vuqie jpuk] rqe fcu thou dsoy liukA ekuo ek= us fn;k I;kj tc] jksik] lhapk rqEgsa LokFkZo”k] rqeus fn;k vikj] vifjfer] ekuo us fQj Hkh u le>kA dkVk] jkSa/kk] dqpyk rqedks] fQj Hkh ik;k I;kj vlhferA viuk lk fouhr rqe eq>s cuk nksA thou ‘ijekFkZ gsrq’ rqe eq>s fl[kk nksA rqEgkjs lEeq[k gw¡ ur~eLrd] gs o`{k fouez] fo”kky] euh"kh! e/kq ’kekZ ‘Oh Divine Tree’ Oh divine tree! such a selfless giver you are.. Yet so detached to stand like an enlightened sage Selfless giving is your only way to live, would you ever ask anything of us? You stand humbly in the service of others, how simple despite that life hidden in your little seed What divine uniqueness you exhibit as universe’s magnificent creation A world without you is like an ocean without water Mankind nurtured you for its own benefit, but generously, you gave all of yourself Alas! Man couldn’t fathom the depth of your loving heart, he exploited and destroyed you endlessly And even then, received selfless giving from your infinite heart Oh divine tree! such a selfless giver you are.. Enable me to transform the expanse of my heart to be like yours Show me the way to your humble greatness Oh divine tree! such a selfless giver you are.. Madhu Sharma

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