Plant

Tree
Deciduous
North America, 1663, Zone 4-10
Tessellated

Bark Type

Tessellated

Having bark in a patten of squares or a chequered appearance.
Conical / Pyramidal

Growth Habit

Conical / Pyramidal

When the outline of a shrub or tree forms a cone or pyramidal shape.
Medium
18 - 28 m (60 - 93 ft )
10 m (33 ft)
2
Yes
Medium

Plant Overview

This large deciduous tree has a stout trunk with ascending branches that form a pyramidal to conical habit. It has dark green lobed leaves that turn golden yellow in autumn and the orange marked, green cup-shaped flowers appear singularly during spring.

 

Liriodendron tulipifera Is naturally found in eastern North America from New England to Ontario and Michigan and extending to northern Florida growing on the lower mountain slopes and the adjoining valleys commonly along rivers or streams at an altitude from 300 m (1,000 ft) to 1,370 m (4,500 ft). It grows in well-drained fertile gravelly to loamy soil with reliable moisture that is acidic to neutral with a pH range from 4.5 to 7.5. It prefers an open sunny position but will tolerate some shade and is frost and cold tolerant but drought tender.

 

The Tulip Tree is grown for its flowers and autumn foliage colour. It is planted in parks or large gardens as a lawn specimen for shade or used along borders. This hardwood tree is suitable for low-mountain regions and establishes in 3 to 6 years and can live up to 300 years. In the wild the tree may attain a height of 58 m (190 ft) but it is normally smaller under cultivation. The timber is used for carving, boat construction and in buildings. Once established it has a medium water requirement, (Scale: 2-drops from 3) preferring organic rich deep soil that is reliably moist during summer.

I.D. 347

UK hardiness zone H6

Climate zones 2 - 12, 14 - 24

USDA Zone 4-10

 

Liriodendron (li-ree-o-DEN-dron) tulipifera (tew-lip-i-fe-ra)

 

Etymology

Genus: Greek - Liriodendron  – ‘leiron’ (a lily) and ‘dendron’ (a tree)

Species:   tulipifera – tulip-bearing, referring to the tulip-like flowers

 

Cultivars

'Aureomaginatum'

This tree has leaves with yellow margins and during autumn turns a brilliant golden colour.

 

'Fastigiatum'

This tree grows to 10 m (30 ft) and has a columnar habit.

 

Magnoliaceae (mag-NOL-ee-AY-see-ee)

 

Note:

This plant tolerates between USDA zones 4a to 10a and grows to 28 m (90 ft)

Fahrenheit       -30º to 35º F

These temperatures represent the lowest average

Celsius            -34.4º to 1.6º C

 

Attention

All photographs and data are covered by copyright. Apart from any fair dealing for the purpose of private study, research, reference or review, as permitted under the Copyright Act, no part may be reproduced by any means with out written permission. All inquiries should be addressed to plantfile.com attention Peter Kirkland.

Leaf

Simple

Simple

The leaf that is not divided.
Lobed

Leaf Shape

Lobed

A leaf that is rounded and forming incomplete divisions from the margin to the centre.
Alternate

Leaf Arrangement

Alternate

Leaves are arranged alternately along the stem.
Entire

Leaf Margin

Entire

A leaf margin with no irregularities (smooth).
Glossy dark green
80 - 100 mm ( 3.1 - 3.9 in )

Additional Information

The 100 mm (4 in) long leaves have 4 pointed lobes with truncate apex and a slightly cordate base up to 45 mm (1 ¾ in) wide with a petiole up to 100 mm (4 in) long. In autumn the leaves turn golden yellow before falling. The terminal reddish buds are up to 12 mm (½ in) long, valvate and covered in white dots. The laterals buds are smaller.

Flower

Cyathiform

Botanic Flower Description

Cyathiform

A cup like shape.
Faint
Solitary

Flower Inflorescence

Solitary

When a flower that arises singly from within the axis of a leaf or terminally.
Yellow - green
45 - 65 mm ( 1.8 - 2.6 in )

Flowering Season

(Southern Hemisphere)

Jan Feb Mar Apr May Jun
Jul Aug Sep Oct Nov Dec

Additional Information

The tree must be semi mature before it flowers. The cyathiform flower is a primitive structure with 6 petals that are up to 37 mm (1 ½ in) long and are green with orange markings on the inside. They are accompanied by 3 reflexed sepals and the  tulip shaped flower appear solitary during mid spring.

Fruit

Cone

Fruit Type

Cone

A conical multiple fruit consisting of valvate scales having naked ovules or seeds. A strobilus. "
Green - brown
No
65 - 70 mm ( 2.6 - 2.8 in )

Fruiting Season

(Southern Hemisphere)

Jan Feb Mar Apr May Jun
Jul Aug Sep Oct Nov Dec

Additional Information

The 70 mm (2 2/3 in) conical fruit are erect brown and woody (cone-like) and contains numerous winged seeds with only a few that are viable. The fruit is persistent on the tree throughout winter. The plant may be reproduced vegetatively.

Environment

Deep moist well drained clay-gravelly loam, tending acid, pH 4.5-7.5
Not normally grown as a container plant, bonsai subject
Full sun-semi shade open position, frost-cold tolerant, drought tender
Cold - cool temperate
Canker, leaf spot, powdery mildew, wilt, aphids, scale, sooty mold

Cultural Uses

The Tulip Tree is grown for its flowers and autumn foliage colour. It is planted in parks or large gardens as a lawn specimen for shade or used along borders. This hardwood tree is suitable for low-mountain regions and establishes in 3 to 6 years and can live up to 300 years. In the wild the tree may attain a height of 58 m (190 ft) but it is normally smaller under cultivation. The timber is used for carving, boat construction and in buildings.

Cultivation

Train to a single leader when young, the crown can be lifted by removing lower branches
Mulch and keep moist during summer when young

Propagation

Stratify seeds for 2 to 3 months during winter in peat and sow seeds in pots and place them in a cold frame to germinate.

Take cuttings during spring and placed them on a misting bench with bottom heat.

Graft cultivars onto seedling understock in autumn. This tree is difficult to transplant.

 

Propagation by Seed (General)

Germination

In order for a seed to germinate it must fulfil three conditions.

 

1. The embryo must be alive (a viable seed).

 

2. The seed must have no dormancy-inducing physiological, physical or chemical barrier to germination; also the seed must be nondormant.

 

3. The seed must have the appropriate environmental requirements, water, temperature and oxygen.

The interaction between these requirements and dormancy is complex and may lead to different environmental requirements that avoid the dormancy of a seed.

 

Sowing Seeds in Containers

There are two general methods for germinating seeds.

Seeds in a flat or germinating bed, through which seedlings are pricked-out then, transplanted into another flat with wider spacing or directly to an individual pot.

 

2. Sowing seeds by placing them in to flats with the appropriate spacing or into individual pots.

This method is normally carried out with medium to large seeds such as woody plants and plants that are difficult to transplant.  

Seedling production normally occurs in a greenhouse / glasshouse, cold frames and on hot beds.

 

Method of Seed Sowing

Fine seed is sown in pots or flats that are no deeper than 70 to 80 mm. using a sterilised well-drained media (soil). Fill the container to 20 mm from the top and sprinkle sieved peat to 3 mm depth.

Press the media down level and firm with a piece of timber and then thoroughly moisten.

 

Mix the fine seed with washed sand and then sow thinly on the surface. These may be lightly covered with sand.

Larger seeds may be covered with media or a hole is dibbled and the seed is placed in the media.

 

Watering Methods

For watering you may either mist the containers from above or place the container in tepid water and allow the water to raise through the pot to the surface of the media, then drain away and do not fill to the top of the container.

 

Place a piece of glass over the pot and store in a protected warm environment (glasshouse).

Seeds germinate best in darkness so shade the containers if in direct sunlight.

 

After the seedlings have sprouted remove the glass and ease the seedlings into direct light.

When the seedlings are large enough prick them out and transplant into larger containers then place them in a shade house to harden off.

Many seeds have different methods of seed preparation for germination such as nicking or cutting the seed coat to allow water penetration, also placing seeds in hot water and allowing it to cool off.

This is particularly important as it is softening the seed coat.

 

Asexual Propagation (Cuttings general)

Propagation from cuttings is possible because every cell of a plant containers the genetic information to create an entire plant.

 

1. Reproduction occurs through the formation of adventitious roots and shoots.

 

2. The uniting of vegetative parts with budding and grafting.

 

3. Taking stem cuttings and layering is possible due to the development of adventitious roots

 

4. Root cuttings can form new shoots then it is possible to join roots and shoots to form a new plant.

 

5. A new plant may be formed from a single cell in an aseptic culture system, (cloning).

 

It is important to propagate vegetatively as this form of cloning retains the unique characteristics of the cultivars or where particular aspects of a plant may be lost if propagated by seed.

 

Equipment Required for Taking Cuttings

 

1. A sharp knife that is not too large or a razor mounted in a handle.

 

2. Good pair of sharp secateurs that is clean.

 

3. A dibbler to make a hole in the media and allow the cutting to be placed in.

 

4. Propagation structures that are either a timber frame with glass or polyethylene cover or a glasshouse.

The object of the structure is to create an environment where the temperature and humidity can be controlled. This can be achieved with a simple cover over a pot with a wire frame and plastic.

This stops the draughts and maintains humidity.

 

5. A hotbed is a useful item as many plants root more quickly if the media is slightly warmer.

Bottom heat is obtained from thermostatically controlled heating cables that are running under the media.

 

6. Misting systems are of great benefit to cuttings as the regulated fogging with water inhibits the cuttings from drying out and as a result the cuttings may be grown in full sun.

This results in faster root development that is less subject to diseases by fungi and bacteria.

 

7. Rooting mediums

The rooting medium must be well drained, sand may be used as long as it is thoroughly washed and leached of all salts. It is very well drained and it is excellent for cutting that root up quickly. Equal parts of sand and peat moss have good results for cuttings, which are left for a period of time to allow the roots to form.

Vermiculite and perlite are also used as a well-drained rooting media but has the same disadvantage as sand having no nutrients. The cuttings must be potted up as soon as the roots developed, or a light application of liquid fertiliser can be applied.

 

Types of Cuttings

Stem cuttings

These are the main types of cuttings.

1. Softwood cuttings

These cuttings are taken from young growth on side shoots and tip growth.

 

2. Semi hardwood cuttings

These cuttings are taken from wood that is firmer and semi ripe usually during mid summer.

 

3. Hardwood cuttings

These cuttings are taken from mature wood normally towards the end of the season.

 

4. Root cuttings

Cut sections of roots to obtain new plants during late winter to early spring.

 

5. Leaf cuttings

Cut the leaf blade in order to obtain new plants during the growing period of the plant.

 

Cutting preparation

Hardwood cuttings

When taking hardwood cuttings remove the leaves and in semi hardwood reduce the number of leaves by half. Cut the wood straight across just below a node or joint. Hardwood cuttings are normally between 100 to 760 mm long and may have either a heel of the older wood attached to the base, or a short section of the older wood at the base. These cuttings are prepared during the dormant season from late autumn to early spring and are made up from previous season's growth.

This type of cutting is used for woody deciduous plants such as Crepe Myrtle, Rose rootstocks and some fruit trees.

The cuttings should be healthy wood with ample supply of stored food as to nourish developing roots, shoots and placed in the rooting media with the aid of a dibbler stick.

 

Softwood cuttings

The cuttings for softwood should be 60 to 130 mm long and be of material with enough substance as to not deteriorate before the new roots appear. Cut below a node and retain the leaves on the upper portion. Place in a well-drained media and maintain a high humidity.

Soaking the cuttings and leaving them standing in water for long periods is undesirable.

 

Herbaceous cuttings

These cuttings are taken from succulent plants such as Geraniums and Coleus. The cutting should be 70 to 130 mm long with leaves retained on the upper end. As in softwood cuttings these require an environment of high humidity. Some fleshy cuttings ooze sap and may require a drying period for a few hours before being placed in the rooting media.

 

Leaf cutting

In these cuttings a leaf blade and petiole or part off is used to raise a new plant.  The original leaf doses not become a part of the new plant as roots and shoots appear from the base of the leaf. In some cases roots appear from the severed veins.

 

Leaf-Bud cuttings

These cuttings incorporate a leaf, petiole and a small piece of the stem. These cuttings are an advantage where the plant uses the axillary bud at the base of the petiole for new shoot growth and maximises available propagation material, as each node will produce a new plant.

As in softwood cuttings these require an environment with high humidity and warmth.

 

Root cuttings

These cuttings are best taken from younger plants during late winter to early spring prior the new season's growth unless the dormant period is during summer.

Trim the roots as they are dug up, to maintain polarity cut strength at the crown end and a slanted cut at the distal end (away from the crown).

 

Root cuttings of small plants are placed in flats in lengths of 20 to 50 mm and laying horizontally on the surface of the soil. These may be lightly covered with sieved sand or media, watered and then placing a piece of glass or polyethylene over the container till roots / shoots appear.

 

Fleshy root cuttings

These cuttings should be 50 to 75 mm long and placed vertically in a well-drained sand media.

Keep the polarity correct and when the roots develop transplant the cuttings into a separate container.

 

Large root cuttings

These cuttings are 50 to 150 mm long are tied up in bundles and placed in boxes of damp sand, sawdust or peat for about three weeks at a temperature of 4.5º C.  When taken out they should be planted in a prepared bed 50 to 80 mm apart with the tops of the cuttings level with or just below the soil level.

 

Grafting and Budding (General)

Grafting and budding have many different purposes.

 

1. It produces clones that are otherwise unobtainable through cuttings, layering and division.

 

2. To gain the benefits of certain rootstock's.

 

3. Changing cultivars of established plants.

 

4. It accelerates the reproductive maturity of seedlings in a hybridisation program.

 

5. Repairing damaged parts of trees.

 

Grafting is the joining two pieces of living tissue as so they grow into a single living plant there is 5 requirements for a successful graft.  

 

1. The stock and the scion must be compatible.

 

2. The scion and stock must have good contact in the cambium region where they are held together by wrapping or wedging.

 

3. The graft must be carried out when the stock and scion are in the right physiological stage. A dormant bud and a stock that is capable of forming a callus.

 

4. Protect all cut areas after the grafting operation with wax or tape.

 

5. After-care of the plant by the removal of shoots from below the graft.

 

Tools and Materials Required for Grafting

1. Knives

There are two types of knives, budding and grafting either folding or a fixed blade. A budding knife may do both jobs if required. The knife must be razor sharp and is usually honed on an, oilstone at a 20-deg angle.

 

2. Grafting Waxes

The ideal grafting wax should adhere well, not wash off, crack, chip and still be pliable enough to allow the callus to grow. A darker wax is often used as the sun will warm it and thus it remains pliable.

 

When applying the hot wax be careful that the temperature is not extreme as to damage the living wood.

The wax is normally heated on a small burner then applied with a brush and there is an aerosol form available for small jobs.

 

3. Wrapping and Tying Materials

String is a simple material to tie a graft in place. Waxed string is good as it adheres to the wax covering. The string should be strong enough to hold the scion in place but weak enough to be broken by hand.

 

Tape is cloth, adhesive or PVC. The nurseryman's adhesive is the most convenient as it can be used for tiering and sealing but do not apply to many layers as this will not disintegrate quickly causing constrictions.

 

Grafting Methods

Whip Grafting

This method is used for smaller material. The scion should contain 2 to 3 buds with the graft occurring in the smooth internode area.

The cut that is made at the top of the stock should be the same as the cut on the bottom of the scion.

These should marry together evenly with a reverse cut that forms interlocking tongues.

If the scion is smaller than the stock it should be placed to one side. After the graft is complete it is secured by wrapping or tying then waxing.

 

Splice Grafting

This is the same as whip grafting except there is no tongue only a slanted cut on both stock and scion.  

 

Side Graft

There are several methods for this but normally it involves the insertion of the scion into the side of the stock that is normally larger.

 

Cleft Grafting

This is an old method that works well for straight-grained plants. It involves the cutting of the stock are right angles and splitting it with a large knife and inserting the prepared tapering wedged scion on the cambium layer. After the graft is complete it is sealed with wax.

 

Wedge Grafting

This type of grafting is carried out during late winter to early spring. The scion used should be 10 to 13 mm long and 8 to 12 mm thick with a wedge shape base that matches the stock cavity.

Using a large knife a wedge should be cut in to the side of stock as to create a 2-cm long V shape, which can be nocked out to form a cavity. More than one cut may be made around the edge of the stock to allow multiple grafts.

 

Matching the cambium layers on the stock and scion gently tapped into place tilting slightly outwards to ensure that the cambium layers cross.

After grafting is completed all exposed areas are to be covered in grafting wax to seal off.

 

Budding

This is a form of grafting that has only one bud and uses only a small section of the bark. It is carried out by slipping bark that is actively growing. The T-budding is a quick, reliable method and is widely used in commercial production.

 

Methods of Budding

 

1. T-Budding

This commonly used method is carried out by making a vertical cut about 2.5 cm (1/10 in) long in the stock. A horizontal cut is then made at the top of the vertical cut and runs one-third around the stock. Twist the knife to open the two flaps of bark.

 

Preparing the Bud

Use a sharp knife to slice 12 mm (½ in) below the bud up and under at a depth of about 25 mm (1 in) finishing just above the bud then a horizontal cut is made through the bark to release the bud.

 

Inserting the Bud into the Stock

The bud is inserted into the stock by pushing down and in side the T cut until the two horizontal cuts are even. The bud union is then tightly tied.

 

2. Inverted T-Budding

This method is used in areas of high rainfall or where a plant weeps a lot. The budding method is the same as a normal T-Bud but has the advantage of draining well. It is important to insert the bud with the correct orientation.

 

2. Patch Budding

Patch budding is carried out during late summer or spring. It involves removal of a piece of bark that is replaced with a bud of equal size. A special double bladed knife is used and this is normally carried out on larger plants.

 

Method of Patch Budding

 

1. The stock is cut about one third around with two parallel horizontal cuts using a double bladed knife.

Vertical cuts join the horizontal and the piece of bark is removed.

 

2. The bud is prepared in the same method and is removed by sliding it off from one side.

 

3. The bud is then inserted into the stock and may require trimming to form a tight fit.

 

4. The union is then wrapped or covered with wax revealing only the bud.

 

There are many variations of the patch bud,

Flute Bud

Ring Bud

I-Bud

 

Chip Budding

Chip budding is normally used before growth starts with small wood in early spring and as growth tappers during autumn.

 

Method of Chip Budding

 

1. Make a cut at 45 deg down and into the stock to a quarter the thickness. A second cut is made 25 mm (1 in) above going down and in to meet the base of the first cut.

 

2. The bud is cut in the same method creating a wedge that is the same size as the stock cut.

 

3. Remove the chip from the stock and place the matching bud into the stock.

 

4. Wrap the union with tape and cover all exposed cuts.

Pests

29
Aphids
Various Aphid Species
Hemiptera
Aphididae

PEST

   NAME

     Aphids

     Various Aphid Species

   ORDER

     Hemiptera

   FAMILY

     Aphididae

Description of the Pest

The common name varies and aphids may be referred to as black fly, greenfly, ant cows or plant lice.

These small insects have soft globular body that is from 1mm to 8mm long and vary in colour from green, yellow, black and pink, with the winged forms being elongated. Both adult and nymphs, have piercing and sucking mouthparts.

Aphids are found on buds, flowers, or leaves and stems, preferring soft new growth. On older leaves the aphids are found in protected positions, such as under the leaf. Certain species of aphids form galls as they suck sap and may be found on the roots of the plant. (E.g. Woolly aphids and Black peach aphids)

Most aphids possess a pair of characteristic tubular projections, known as cornicles; these secrete a pheromone and a waxy fluid, which is thought to protect them from some of their predacious enemies.

White exoskeletons, honey dew and sooty mould indicate the presence of Aphids


Balsam Twig Aphid (Mindarus abietinus) is greenish and covered in a white wax and is normally found on the young shoots of conifers bending and killing the needles. It is found on Abies and Picea species.


Aphid and their exoskeletons    on underside of a leaf


Black Citrus Aphid (Toxoptera aurantii) has a soft plump green body and the black coloured adults may or may not be winged. They feed in groups, curling leaves and producing honeydew attracting sooty mould.


Green Peach Aphid (Myzus persicae) is a soft plump green insect up to 0.2mm long and may be wingless. The nymphs are yellowish green and are responsible for spreading viruses in Dianthus species.


Spruce Gall Aphid (Chermes abietis) form cone shaped galls up to 12mm long resulting from the feeding. The wingless female adult lays eggs on the stems and the immature females overwinter on bud scales. Large infestation will weaken trees such as Picea abies and Pseudotsuga menziesii.


Tulip Bulb Aphid (Anuraphis tulipae) is small, waxy grey coloured and infests the underside of the bulb scales or rhizomes. They occur in the ground or on above ground parts and during storage.


Life Cycle

These insects have a Hemimetabolous life cycle, i.e. The nymphs resemble the adults.

During spring all eggs produced hatch as female nymphs. Adult Aphids are capable reproducing without fertilisation.  The males are only produced in some species as the weather cools down, and the day length shortens.


Aphids are capable of giving birth to living young and large populations build up quickly during summer. Over crowding causes the aphids to become smaller, less fertile and produce more winged forms that can migrate to other host plants.

There are many different types of aphids and the life cycle varies from warm to cold climates.


Typical life cycles

Distribution of the Pest

World wide


Period of Activity

In warm climates they are seen throughout the year, but aphids dislike hot dry or cold conditions and heavy rain will decrease the population. In cold areas aphid eggs are laid around a bud base or other protected areas of the plant during autumn and emerge as nymphs during spring, feeding on the new growth.

Numbers build up quickly in the warmer months of the year. Some species feed during winter on Sow thistles.


Susceptible Plants

There is a wide range of plants attacked, from roses to vegetables, shrubs and trees. Certain aphids attack a specific genus while others have a wide range of host plants. Many are capable of transmitting plant virus diseases.


Adults and nymphs feeding    A colony of aphids


Acer species are attacked by several aphids including the Norway Maple Aphid (Periphyllus lyropictus) which is a greenish with brown markings and secret honeydew, preferring Acer platanoides. Other aphids include (Drepanaphis acerifolia) and (Periphyllus aceris) which are commonly found on the underside of leaves.


Acer species are also attacked by the Woolly Maple Aphid (Phenacoccus acericola) which covers the undersides of the leaves with a cotton-like mass


Alnus species are infested with the Alder Blight Aphid (Prociphilus tessellates) which is blue-black adult that forms woolly masses on the down-turned leaves. The nymphs overwinter in bark crevices.


Aquilegia species are attacked by several aphids including (Pergandeidia trirhoda) which is a small, flat cream coloured insect that is found on young branches and the underside of leaves.


Betula species may be attacked by the European Birch Aphid (Euceraphis betulae) which is small and yellowish or the Common Birch Aphid (Calaphis betulaecolens) which is large and green producing ample honeydew for sooty mold to grow on.


Callistephus species may be attacked by the Corn Root Aphid (Anuraphis maidi-radicis) causing the plant to become stunted, the leaves wilt and turn yellow. The aphids feed on the roots producing honeydew and are dispersed to other host by ants. It is also attacked by the Potato Aphid (Macrosiphum solanifolii).

Carya species are attacked by Gall Aphids (Phylloxera caryaecaulis) which is found on the leaves, twigs and stems forming galls and turning them black.


Chaenomeles and Gladiolus species, new growth and leaves become infested with the aphid (Aphis Gossypii)


Cupressus macrocarpa may become infested with the Cypress Aphid (Siphonartrophia cupressi).


Cyclamen species are attacked by the aphid (Myzus circumflexus) and (Aphis gossypii) which can infest healthy plants.

Dendranthema, Dianthus  and Crocus species are attacked by several types of aphid including the Green Peach Aphid (Myzus persicae) and the Chrysanthemum Aphid (Macrosiphoniella sanborni).


Hibiscus species are attacked by the aphids (Aphis craccivora)  and (Aphis gossypii), both congregate towards the branch tips and may cause leaf curl. Normally only seen in sub-tropical climates.


Aphids on a stem    Mandevilla species


Larix species is attacked by the Woolly Larch Aphid (Adelges strobilobius). The winged adults deposit eggs at the base of the needles during spring and white woolly areas appear attached to the needles where the adult aphids feed. The young aphids overwinter in the crevices of the bark.


Mandevilla species is attacked by aphids that congregate towards the branch tips and may cause leaf curl.


Pinus species is attacked by several species of aphid including Pine Bark Aphid (Pineus strobi), Pine leaf Aphid (Pineus pinifoliae) and the White Pine Aphid (Cinara strobi).


Primula species are attacked by four species of aphid including foxglove, and green peach aphid.


Rudbeckia, Delphinium, Chrysanthemum and Helianthus species are attacked by a bright red aphid (Macrosiphum rudbeckiae).


Sorbus aucuparia is affected by the Rosy Apple and Woolly Apple aphid which attacked the foliage and young shoots.

Spiraea species are attacked by the Aphid (Aphis spiraecola) which feeds on the young shoots and flowers.


Tropaeolum species are attacked by the Black Bean Aphid (Aphis fabae), which is found in large numbers on the underside of the leaves, turning them yellow and causing them to wilt then die.


Tulipa, Iris, Freesia, Gladiolus and Zephyranthes species are infested with the Tulip Bulb Aphid.


Ulmus species are infected by two types the Woolly Apple Aphid (Eriosoma lanigerum), which curls and kills young terminal leaves and the Elm Leaf-Curl Aphid (Eriosoma ulmi) which occasionally attacks the trees.


Viburnum species are attacked by the Snowball Aphid (Anuraphis viburnicola). This aphid congregates at the end of the branches causing the leaves to curl and become deformed under which they hide.


Aphids on Quercus robur


Damage Caused

Buds that have been attacked may not open, leaves and twigs become twisted or distorted and wilt. The aphids also produce honeydew, which is sticky and attracts sooty mould (fungus). This fungus forms a thick layer over the leaf, fruit or stems reducing the plants photosynthesis capability. The sooty mould spoils the plants appearance and its fruit, as does the insects white exoskeletons.


Control


Cultural Control

Aphids may be removed from a plant by hosing them off with water (limited success) or applying soapy water to aphids.. Another organic sprays can be efficient in controlling aphids. Aphids  may also be removed physically by hand for small colonies on spine less plants. Species that live under ground are difficult to control but cultivation of the surrounding soil may help in controlling the infestation. (limited mainly to annual or commercial crops)

Reflective mulch around the plants also reduces numbers by repelling the insect this material is available commercially. (Reflective mulches are mainly used in market gardens for avoiding the Green peach Aphids) Resistant rootstocks are available to avoid some root feeding aphid of commercial plants, e.g. Vines and fruit trees


Biological control

Aphids are attacked by several insects includes parasitic wasps or predators such as ladybirds/ lady beetles, hover flies, lacewings, spiders.


   Parasitised aphids


Chemical Control

Aphids may be controlled by spraying with a contact or systemic insecticide. The type of application used will depend on the plant is being attacked.

Aphids can be suffocated and therefore controlled with the use of e.g. White oil, Pest oil, Soapy water from soap such as Lux Flakes ®

Note

It is your responsibility by law to read & follow the directions on the label of any pesticide


Monitoring

Aphid are attracted by yellow colour and traps such as boards painted yellow and covered in glue or sticky substance will attract and trap the insects.  There is also a commercially sticky yellow tape that can be attached to susceptible plants

Amendments by B. Sonsie Dip Hort Sc Burnley


87
Scale Insect
Various Scale Species
Hemiptera

PEST

 

   NAME

     Scale Insect

     Various Scale Species

 

   ORDER

     Hemiptera

 

Description of the Pest

Generally scales are soft bodied insects that have a hard (armoured) or soft covering to hide under. They have piercing and sucking mouth parts that are attached to the host, feed off sap and soft scales commonly producing sweet honeydew, which in turn attracts sooty mould and ants.

The adult female has a circular or oval covering depending on the species and is up to 8mm across. The first stage (crawlers) hatch and wander around the leaf surface until finding a suitable place to suck sap, normally in colonies and the smaller male is relatively inconspicuous.

 

Hard Scale                   Soft Scale, attending Ants

 

Cactus Scale (Diaspis echinocacti) has a circular greyish female and a narrow white male scale and is commonly found on house plants.

 

Chain Scales (Pulvinaria species) adult females are obvious with large group of eggs that are white or cottony-like, and the tiny young light green scales are flat and oval-shaped up to 2mm long. The legged nymphs are normally arranged from head to tail along the mid rib of the leaf, and may move to a new position to feed. They excrete honeydew and attract sooty mould and are found on Acacia and Acronychia species.

 

Chinese Wax Scale

 

Chinese Wax Scale (Ceroplastes sinensis) is a domed wax scale that has dark spots around its margin and immature scales form waxy material around there margins.

 

Fern Scale on Aspidistra elatior

 

Fern Scale or Coconut Scale (Pinnaspis aspidistrae) appears as flecks up to 0.15mm long with a white covering over the male congregating on the underside of the fronds on the axils and among the sporangia causing them to turn yellow. Many species of fern are susceptible to infestation.

 

                  Flat Brown Scale

 

Flat Brown Scale (Eucalymnatus tessellates) are light brown up to 0.5mm long, flat and closely attached both sides of the leaf and causing yellowing of the foliage.

 

Juniper Scale (Diaspis carueli) is tiny and circular, white maturing to grey-black and as it feeds the needles turn yellow and die.

 

Oleander Scale (Aspidiotus hederae) is a pale yellow circular scale up to 3mm across and is found in dense colonies on the stem or leaves.

 

Tea-tree Scale (Eriococcus orariensis) are a creamy blue colour normally packed along the branches and are plump and rounded to 4mm across.

 

                  Wattle Tick Scale

 

Tick or Wattle Scale (Cryptes baccatus) adult is domed, blue-slate colour with a leathery covering up to 10mm long. All stages of growth are found in groups of over forty, packed along the stems and normally tended by ants as they produce large amounts of honeydew. A serious pest of Acacia species found inland or coastal from temperate to sub tropical climates and commonly accompanied by Sooty Mould.

 

Toxic Scale (Hemiberlesia lataniae) is a tiny flat rounded scale up to 0.15mm long and is white to pale pink. It is normally found in colonies on the small branches and twigs of shrubs. It injects a toxic substance into the host as it sucks sap causing the death of the branch.

 

Wattle Scale (Pseudococcus albizziae) is soft, plump and secrets cotton-like threads. It is not a true scale insect and is simular to mealy bugs. It is reddish-brown up to 0.4mm long and secrets large amounts of honeydew as it sucks sap in colonies along the branches.

 

Life Cycle

These insects have a Hemimetabolous life cycle, ie. When the immature nymphs resemble the adults.

 

Appearance of the Pest

All parts of the plant above the soil may be attacked, but normally the stems and leaves and scale tends to favour well-lit positions.

 

Period of Activity

The nymphs and females are active for most of the year, in warm climates. Once they selected a position they attach and don't move. Normally the winged or wingless males are mobile and only soft scales produce honeydew.

 

Susceptible Plants

There is a wide range of susceptible plants including citrus, willows, holly, and many ornamentals, such as roses or Paeonia species. It also attacks indoor or glasshouse plants and Australian native plants such as wattles, hakeas, grevilleas and eucalyptus.

 

Acacia species are attacked by the Tick or Wattle Scale, which infest twigs and small branches and heavy infestations will kill the host plant.

 

Acer species are attacked by the Cotton Maple Scale (Pulvinaria innumerabilia) which prefers Acer saccharinum. Nymphs first attack the leaves and the brown adult scale is covered in a woolly mass up to 14mm across, normally found on the underside of the stems and twigs.

 

Acmena smithii, Melaleuca, Syzygium and Pittosporum species are attacked by the Chinese Wax Scale.

 

Aesculus species are attacked by several scale insects including the Walnut Scale (Aspidiotus juglans-regiae) which is saucer-shaped and attacks the main trunks.

 

Agave species are susceptible to several types of scale including (Aspidiotus nerii), (Aonidiella aurantii) and (Pinnaspis strachani), but generally do not require control.

 

Asplenium australasicum

 

Asplenium australasicum is susceptible to Coconut Scale or Fern Scale (Pinnaspis aspidistrae). It is normally found on the under side of the fronds. Small infestations cause little damage.

 

Bougainvillea species may be attacked by the soft scale (Coccus hesperidum) outdoors or under glass.

 

Calluna and Vaccinium species are attacked by the Oyster Shell Scale (Lepidosaphes ulmi).

 

Camellia species may be attacked by the Florida Red Scale (Chrysomphalus aonidum), which is small, circular and black and is found firmly attached to the underside of the leaf along the veins. On inspection after removing the scale the insect has a pale yellow body. Camellias are also attacked by a large variety of scale insects including Tea Scale and Camellia Scale.

 

Carpinus species may be attacked by the scale (Phenacoccus acericola). It is found on the underside of the leaves forming a white cotton-like clump along the veins.

 

Casuarina and Allocasuarina species may be attacked by the Casuarina Scale (Frenchia casuarinae), a black hard scale that is upright to 4mm with a pinkish body. During attachment the surrounding tissue swells up and in time can, form galls. This weakens the wood and in severe infestations may kill the tree.

 

Cotoneaster species are attacked by up to four species of scale including the Oyster Shell Scale (Lepidosaphes ulmi).

 

Cupressus species are attacked by Bark Scale (Ehrhornia cupressi) is pink and covered in white wax. Heavy infestations cause the leaves to turn yellow or reddish.

 

Flat Brown Scale on Cycas revoluta

 

Cycads, palms and some species of Callistemon are attacked by the Flat Brown Scale.

 

Erica species are attacked by several species of scale including, Greedy, Oleander and Oystershell scale.

 

Jasminum species can be infested with up to twelve types of scale.

 

Juniperus x media and other conifer species are attacked by the Juniper Scale.

 

Leptospermum species are attacked by the Tea-tree Scale which produces ample honey dew that promotes sooty mould.

 

Palm and Fern species are susceptible to attack by the Coconut Scale or Fern Scale (Pinnaspis aspidistrae) which infests the underside of the leaves. They are also hosts for many other scale species such as red, cottony cushion and tea scale.

 

Pinus species are attacked by several species of scale including the Pine Tortoise Scale (Toumeyella numismaticum) and the Red Pine Scale (Matsucoccus resinosae).

 

Polygonum odoratum is attacked by a small brown scale.

 

 

Sorbus aucuparia is attacked by a five species of scale insect, including Black Cottony Maple, San Jose and Scurfy. Generally they suck on the sap of the new growth and leaves.

 

Strelitzia species are attacked by the Greedy Scale (Aspidiotus camelliae).

 

Damage Caused

Leaves become yellow and are shed prematurely and there may be twig or stem die-back. When the infestation occurs on fruit, the fruit is small and its skin becomes pitted and cracked. Small trees and saplings that are heavily infested may be seriously damaged or die. Sooty mould can cover fruit or leaves causing a secondary problem.

 

Cactus Scale can completely cover the host cactus sucking sap and causing it to die.

 

Cultural Control

Dead or damaged parts of the plant should be removed and destroyed including fallen fruit. Small infestations may be removed by hand or squashed on the stems. Healthy plants are less susceptible to attack, so maintain vigour of the plant and avoid using high-nitrogen fertiliser that produces excessive soft young growth.

When pruning susceptible plants paint the cuts with antifungal sealant paint as scale insects are attracted to the sweet smell of the sap. This will reduce the infection rate of the plant.

 

Biological Control

Natural predators such as parasitic wasps may reduce numbers of active nymphs; parasitic wasps are bred commercially in some areas for this purpose. It should be noted, however, that wasps would avoid dusty conditions.

Other predators that assist in control are assassin bugs, ladybirds, lacewings, hover flies and scale eating caterpillars. A variety of birds also attack scales.

The control of ants that transport aphid from one host to another also reduces infestation and can be carried out by applying at least three greased bandages 5mm apart around the stem or trunk of the plant.

 

Chemical Control

Spray the entire plant with dilute white oil solution; a follow-up spray may be required after four weeks, for heavy infestations. Spraying of chemicals will also kill of natural predators and in some cases the secondary scale infestation is more prolific especially when using copper based chemicals.

Some chemical controls, such as methidathion, are available - please seek advice from your local nursery as to the suitable product for your area.

Note

Always read the label for registration details and direction of use prior to application of any chemicals.


Diseases

56
Sooty Mould
Various Sooty Mold Species

DISEASE

   NAME

     Sooty Mould

     Various Sooty Mould Species


Description

A fungal problem related to honeydew that is secreted from other insects. The fungus will not infect the host plant.


Symptoms

A soot-like dry black fungus appears on areas of the plant where honeydew is found. The fungus spreads and becomes thick restricting the plants capability to photosynthesize. The fungus can also appear on fruit spoiling its appearance and gives the plant an unattractive look.


                  Gardenia augusta


Source and Dispersal

It is found on other infected plants and soon spreads by wind to other susceptible plants.


Favoured Conditions

It is occurs when insects are producing honeydew, normally through the growing period.

        

Affected Plants

These fungi can found on most plants particular plants that are infected with scale insect that produces honeydew.


Pittosporum eugenioides      Camellia japonica


Callicarpa species are infected with Black Mould (Meliola cookeana) with its black mycelium growing on all parts of the plant including twigs and leaves.


Non-chemical Control

To reduce sooty mould it is required to controlling insect numbers on the plant. Affected plants may have the dry sooty mould rubbed or hosed off.


Chemical Control

Fungicides are not required, but the control of the insect producing honeydew is required.

Note

Always read the label for registration details and direction of use prior to application of any chemicals.


60
Verticillium Wilt
Verticillium dahliae

DISEASE

   NAME

     Verticillium Wilt

     Verticillium dahliae


Description

This is a soil based fungus that attacks the root hairs and travels throughout the plants vascular system.


Symptoms

With annuals or perennials such as dahlias lower leaves wilt, turn brown and die and the stems appear normal until the base splits open and turns blackish. This may extend throughout, killing the plant. With larger trees the fungus causes the leaves at the end of the branches wilt and die off.



Verticillium albo-atrum is a soil born fungus that normally infects the roots acting on the water conducting cells by restricting flow causing the plant to wilt. On trees the leaves suddenly wilt and die. This may happen on individual branches on one side of the tree. Other symptoms are leaves form smaller than usual turning yellow and the plant may not shoot the following season. Trees may die over a short or long period of time depending on the severity or number of infections it has incurred and Acer saccharinum and Catalpa species are most susceptible.


Source and Dispersal

It is found in the soil and dispersed by movement of soil i.e. in containers or on machinery. The fungus may survive in the soil for many years.


Favoured Conditions

Moist poorly drained soils are prone to fungus and during the cooler humid months the fungus is most active.        


Affected Plants

There is a wide range of hosts including tomatoes, potatoes, chrysanthemums and other perennials. It also found in shrubs and trees.

Acer, Achillea, Koelreuteria , Paeonia  and Syringa species are infected by Verticillium albo-atrum causing wilting. Erythrina x sykesii may also become infected.


Berberis species are infected with Verticillium albo-atrum causing the leaves to turn brown, shrivel then die.


Non-chemical Control

Cultivate soil to improve drainage and aeration. Cut down and destroy any infected plant material and when taking cuttings from a susceptible plants quarantine them, to ensure they are not infected. Infected soil may be allowed to lay fallow for 2 to 3 years and when replanting used resistant plant varieties.


Chemical Control

For quick control of a cultivated area the soil will require treatment with a fungicide. Consultation with your local Department of Agriculture is advised.

Note

Always read the label for registration details and direction of use prior to application of any chemicals.


52
Powdery Mildew
Various Powdery Mildew Species

DISEASE

   NAME

     Powdery Mildew

     Various Powdery Mildew Species


Description

Powdery mildew covers arrange of fungal infections most with simular characteristics of white powdery areas appearing on the leaves and flowers.


     White powdery area     



Symptoms

Powdery mildew (Oidium species) affects the following five plant groups with slightly different characteristics.


Cucurbits firstly form white spots on the underside of the leaves. Under optimum conditions the fungus spreads to the upper surface covering the entire leaf causing it to die. It may also extend to the stems slowing the growth of the plant and may reduce the size of the fruit.



Grape leaves, flowers and fruit are attacked with the appearance of greyish-white powdery spots. Infected flowers set poor quality fruit and infected fruit splits open and dries out.


Pawpaw leaves become infected on the underside at first then spreading covering the entire leaf. The fruit forms irregular light grey spotted areas that damages the surface and under the surface causing the fruit to misshapen and reducing its market value.


Rose leaf and buds are covered in a fine white powdery coating and in severe cases it extends to the stems. When young leaves are infected they become distorted and older leaves develop blackened areas. Infected flower buds may fail to open and opened blooms may be discoloured or distorted.


Strawberries show different signs of infection with the leaf margins first rolling upwards then developing purplish irregular blotches along the veins.  The infected flowers may fail to set fruit and if fruit is produced it is small, hard fails to ripen. Semi mature fruit that is infected has dull appearance and may form cracks or split open.


The Powdery Mildew (Sphaerotheca lanestris) infects leaves and twigs. The under side if the leaf firstly has a white mealy growth that matures to felt-like brown mycelium that can cover the entire leaf, and the twig tips. It is only one of the many types that infect Quercus species.


Source and Dispersal

The spores overwinter in fallen leaves, dormant buds, seed and infested plants. It is dispersed by wind.

Favoured Conditions

Generally it prefers warm humid conditions, but failing to germinate when it is raining. The fungus that attacks Pawpaw prefers cooler conditions disappearing in the warmer months.        


Affected Plants

There are many plant species ornamental trees and shrubs that are attacked by Oidium species including; Roses, African Violets, Cucurbits, Grapes, Pawpaw, Strawberries, Hydrangeas, Ajugas, Antirrhinum, Oaks and Photinias.


Acer species are infected by the powdery mildews (Uncinula circinata) and (Phyllactinia corylea) but are not normally serious.


Aesculus species are infected by the powdery mildew (Uncinula flexuosa) which forms a white mold on the underside of the leaves.


Arenaria,Cuphea, Erica and Eschscholtzia species are infected by the powdery mildew (Erysiphe polygoni). This fungus is greyish or white and covers leaves or young shoots. Heavenly infected leaves turn brown and fall from the plant. The plant eventually dies.


Aster species are infected with the powdery mildew (Erysiphe cichoracearum) which is more prevalent on the lower part of the plant.


Ceanothus, Corylus, Platanus, Syringa and Weigela species are infected by the powdery mildew (Microsphaera alni) particularly London Plane. The mycelium forms a felt-like cover on the leaves.


Celtis species are susceptible to the powdery mildew (Uncinula parvula) and (Uncinula polychaete). This fungal problem can affect either side of the leaf, which can have spots or be completely coved in mildew. The fruiting bodies appear on the opposite side of the mildew.


Cornus species leaves are infected by the powdery mildew (Microsphaera alni) and (Phyllactinia corylea), covering the leaves in a whitish fungus.


Dahlia species are infected by the powdery mildew (Erysiphe cichoracearum) that forms white powdery areas on the leaf surface.


Lagerstroemia species are infected by the powdery mildew (Uncinula Australiana) that forms white powdery growth on the leaves and may also distort the infected foliage.


Populus and Salix species are infected by a white powdery mildew (Uncinula salicis) that produces black fruiting bodies with a curled tip, but is not normally a major problem.


                  Quercus robur


Quercus species are susceptible to several powdery mildew fungi including (Sphaerotheca lanestris), (Erysiph trina) and (Phyllactinia corylea). Generally white mealy growth appears on the leaves, normally on the underside turning the infected areas brown and then the leaf dies. The infection may spread to the twig tips causing dieback. Control may be difficult and unwarranted on large trees but nursery stock may be sprayed with a fungicide during susceptible periods.  


Rosa species are also infected by the powdery mildew (Sphaerotheca pannosa).

Rudbeckia and Senecio species are covered in white fungus (Erysiphe cichoracearum) which infects leaves, flowers and stems. This results in the plant becoming stunted.


Senecio species are infected by the powdery mildew (Sphaerotheca fuliginea) which forms circular white powdery areas on the leaves.


Spiraea species are infected by the Powdery Mildew (Microsphaera alni) and (Podosphaera oxyacanthae).


Ulmus and Rhododendron (Azalea) species are also infected by (Microsphaera alni). Circular patches of white powdery growth appear on the leaves.


Veronica species are sometimes infected by the powdery mildew (Sphaerotheca humili) causing a white coating to appear on the leaves. Not normally a major problem.


                 


Zinnia elegans are commonly infected by the powdery mildew (Erysiphe cichororacearum), which appears on both sides of the leaves as a greyish powdery cover and may be transmitted by seed.


Non-chemical Control

Choose less susceptible species and when planting space the plants to allow good air circulation. Avoid overwatering and try to keep the foliage dry. Affected plants may be dusted with powdered sulphur or sprayed with a milk mixture to discourage mildew. Vegetables that are infected with mildew should be removed and replaced with new young plants, as they are more resistant to infection.


Chemical Control

Prenatitive spraying during warm humid conditions using a suitable fungicide such as wettable sulphur, bitertanol, carbendazim, fenarimol and triforine helps control the problem.

Note

Always read the label for registration details and direction of use prior to application of any chemicals.


62
Canker (General)
Various Canker Species

DISEASE

   NAME

     Canker (General)

     Various Canker Species


Description

This is a fungal problem that enters the plant through wounds causing dieback of twigs and stems.


Symptoms

The stems become discoloured (pale brown) usually from a pruned point, working its way down the stem and normally intersecting or surrounded with live cambium. The bark splits or cracks, foliage dies and infected areas can develop tiny black fruiting bodies. Heavy infected plants eventually die, though certain varieties are resistant halting the spread of the infection.


                 


Black Canker (Phyaslospora miyabeana) forms dark brown spots with concentric rings on the upper leaf surface and grey spots on the stems. The tiny black fruiting bodies develop in the stem lesions. It is found on Salix species and persistent attacks will kill the tree.


The Canker (Cytospora valsa) causes the browning and death of branches in Picea abies and Picea pungens. This infection occurs normally from the base of the tree with infected needles falling, and white resinous patches appearing on the bark accompanied by cankers with tiny black fruiting bodies.


The Canker (Corynneum cardinale) is a casual fungus that invades wounds and infects living bark and associated cambium turning the foliage yellowish. As it spreads it girdles the branch killing it and ultimately the top of the tree dies out. Cankers eventually form in the trunk and ooze resin. It is found on Cypress.


   Platanus x hybrida


Cankerstain (Ceratocystis fimbriata f. platani) forms sunken cankers on the trunk and large limbs forming longitudinal cracks and roughened bark. Infected areas form callus around the margins which dies off and when cut open, dark coloured streaks are revealed extending to the central pith. These streaks then radiate out into uninfected wood resulting in the thinning of the crown and producing unusual small leaves. It is normally transmitted through poor tree surgery techniques and infected tools.


Cytospora Canker


Cytospora Canker (Cytospora chrysosperma) is a casual fungus that infects the young twigs, then moving to the stems, branches and trunk causing brown sunken areas to appear that is covered in red pustules. The fungus tends to attack trees that are in poor health. Control requires the removal of infected branches and improved culture to regain the plants vigour. Sorbus aucuparia, Salix and Popular species are susceptible.


Cypress Canker


Cypress Canker (Seiridium species) enters the plant through wounds or through insect damage causes the bark to spread revealing brown powdery spores that are accompanied by oozing resin. The canker eventually girdles the branch or trunk causing ringbarking and the death of the plant.


Nectria Canker (Nectria Cinnabarina) forms cankers on the twigs and small branches producing red fruiting bodies and eventually killing the tree. It is found in many parts of the world infecting a range of trees including hardwoods.


          Populus nigra


Poplar Canker (Cryptodiaporthe populea) infects the cambium layer damaging the bark and sapwood where the elongated sunken canker forms. Branches are girdled causing the upper portion to die off. This is a serious problem for Populus nigra var. Italica entering the plant through wounds or the leaves then spreading to twigs and branches. Control is difficult as removal of infected parts will not eradicate the problem, but encourage it. Young plants may be sprayed with a copper based fungicide to reduce leaf infection and heavily infected plants should be removed the burnt.


Stem Canker of Red Flowering Gum (Sporotrichum destructor) enters through wounds in the bark forming cankers in the trunk and branches, splitting the bark apart, revealing the wood and infesting the surface with powdery spores. This infection causes the leaves to wither and then the branches die, eventually killing the tree.


Stem Canker (Strumella coryneoidea) is a casual fungus that forms on the trunks of trees as a smooth, dispersed or sunken infection. On mature trees the infection sheds the bark with the canker forming callus tissue around the margins and the centre being exposed. These cankers then tend to extend up and down the trunk, only girdling over a long period of time. It is found on Quercus, Fagus, Aesculus species, and Acer rubrum , Nyssa sylvatica, Carya ovata and Morinda citrifolia.



Source and Dispersal

The spores are found on infected dead plant material and can be dispersed by wind and with splashing water.


Favoured Conditions

It prefers a warm humid conditions and plants that have a wounds derived from poor pruning techniques and insect or other damage, especially if water is allowed to settle on the wound.

        

Affected Plants

Cankers may infect a wide range of trees and shrubs with some species being specific to its host. Examples are listed below.


Abies species are infected by several cankers including (Cytospora pinastri), (Cryptosporium macrospermum) and (Scoleconectria balsamea). These fungi form dead sunken areas on the trunk and branches.


Alnus species are infected by a few cankers including (Nectria coccinea) and (Physalospora obtusa) these attack the branches causing die back.

Betula species may be infected by the Canker (Nectria galligena) that occurs in the forks of trees causing splitting and cracking of the bark by swelling, to reveal the canker. Callus rings may form around the affected areas as a defence mechanism triggered by the tree.


Buxus species are infected by the Canker (Pseudonectria rousseliana) which shows signs of poor new growth during spring with the leaves turning from light green to a tan colour. These leaves tend to lay flat along the stems and reddish pustules appear both on the stems and leaves. The bark becomes loose and on inspection reveals a darkish colour underneath. It is difficult to control and the canker can kill the plant.


Castanea species are infected by the Twig Canker (Cryptodiaporthe castanea), a fungal problem that causes significant damage to the twigs and small branches, but tends to attack stressed trees.


Cercis and Ribes species are infected by the Canker (Botryosphaeria ribis) which forms small sunken areas on the stems causing wilting and eventually killing the branch by girdling. The cankers turn the bark black then split it open and the adjoining wood becomes discoloured. This is a serious problem for this and many other plant species.


Cotoneaster, Betula, Catalpa and Aesculus species are infected by the canker (Physalospora obtusa).


                  Cypress Canker


Cupressus species and Chamaecyparis lawsoniana are susceptible to Cypress Canker (Seiridium species) which causes leaf browning and then girdles the trunks resulting in ringbark. There is also another Canker (Coryneum cardinale) that has simular characteristics and is found in the northern hemisphere.


Cupressus sempervirens is infected by Cytospora Canker (Cytospora cenisia var. littoralis).


Larix species are susceptible to several fungal cankers including (Trichoscyphella wilkommii), (Trichoscyphella ellisiana), (Aleurodiscus amorphus), (Leucostoma Kunzei) and (Phomopsis spp.)


Nyssa sylvatica is attacked by three cankers including (Strumella coryneoidea).


Pinus species are infected by many types of cankers.


Platanus species are infected by Cankerstain.


Cytospora Canker on Salix babylonica


Pseudotsuga menziesii Douglas Fir is attacked by several cankers including (Cytospora species), (Dasyscypha ellisiana), (Dasyscypha pseudotsugae), (Phacidiopycnis pseudotsugae) and (Phomopsis lokoyae). These infections normally do not require control and are more prevalent on the coastal form.


Salix and Populus species are infected by several cankers including Cytospora Canker (Cytospora chrysosperma), Hypoxylon Canker (Hypoxylon pruinatum), Septoria Canker (Mycosphaerella populorum) and Branch Gall (Macrophoma tumefaciens). Many of these fungi can cause the death of the plant.


Thuja orientalis, Cupressus and Juniperus species are infected by the canker (Corynneum cardinale).


Tilia and Acer species are infected by (Nectria cinnabarina) attacking twigs or branches.


Tsuga species are infected by several cankers including (Dermatea balsamea) and ( Cytospora species).


Ulmus species are infected with up to eight fungal cankers including (Apioporthe apiospora) and (Nectria coccinea).


Vaccinium ovatum is infected by the canker (Coryneum microstictum) which attacks the stems.


Vinca species are infected by canker-dieback (Phomopsis livella) causing the shoots to wilt, turn brown and die. This can reduce the plant to ground level, and normally occurs during rainy periods.


Non-chemical Control

It is very difficult to control and correct pruning techniques with sharp tools for repairing wounds or prune well below the infected areas. Ensure that there are no ragged edges on the cuts and the angle should cut allows water to run off or dress the wound. Plant resistant varieties when available. Heavily infected trees should be removed to avoid spreading the disease.

Improve the culture of the affected plant to increase vigour for greater resistance.


Chemical Control

There is no satisfactory chemical control and prevention is imperative.

Note

Always read the label for registration details and direction of use prior to application of any chemicals.


26
Leaf Spot (General)
Various Leaf Spot Species

DISEASE

   NAME

     Leaf Spot (General)

     Various Leaf Spot Species



Description

There is a wide variety of fungal leaf spots that infect perennials, shrub and trees. Some are specific to the host while others can affect a range of plants.


Symptoms

Generally light brown to purplish or blackish spots appear on the leaf and form concentric rings of fruiting bodies. The spots may leave holes, perforating the leaf or expand with pale green to yellowish margins and when the holes merge the leaf normally dies. There are many different types of leaf spot, some are discussed below.


Alocasia species     


Alternaria Leaf Spot (Alternaria nelumbii) forms a small reddish brown spots that are boarded in light green, and as they develop in size the leaf curls and dies from the margin inwards. Normally occurs on Nelumbo species (water lilies).


Helminthosporium Disease


Helminthosporium Disease (Bipolris species), (Drechslera species) and (Exserophilum species) are responsible for several leaf spots that occur on all Turf Grass species. Generally they form black or white spots that may be faded and produce masses of spores in the thatch during late summer, under humid conditions. The life cycle is short and when conditions are favourable spores are splashed onto the foliage from the thatch, causing wide spread infection. Cynodon dactylon (common couch) is most susceptible and found in bowling or golf greens where it is a serious problem.


Banana Leaf Spot     


Banana Leaf Spot (Mycosphaerella musicola) is found on many species of banana causing pale yellow streaks on the young leaves to turn brown with dark spots. The leaf then becomes dried, brown and dead commencing from the margins, eventually the leaf dies. Control requires removal of infected foliage or the spraying of a fungicide and fungicides should not be used during the fruiting period.


                  Lophostemon confertus (Brush Box)


Leaf Spot on Brush Box (Elsinoe species). This is a casual fungus that attacks the epidermal layer of the leaf, forming circular spots that are up to 25mm across and are often restricted by the main vein.  These spots are a dull yellowish brown but can also have purplish patterns.  A leaf may have more than one spot develop on its surface and normally appears on scattered leaves throughout the tree.  This doesn't affect the vigour of Lophostemon confertus.


Palm Leaf-scab (Graphiola phoeicis) appears as yellow spots and develop into scabs or warts that are outwards hard and dark but with a soft centre with powdery yellowish brown spores. The infected leaves eventually die.


Palm Leaf Spot, Chamaedorea elegans


Palm Leaf Spot (Pestaloptiopsis species) appears as a small spot with a dark centre on the leaves and affects palms that are growing in shaded humid positions and normally control is not required, though infected fronds should be removed.


Source and Dispersal

Infection source is other contaminated plants and the spores are spread by wind or by splashing water.  The fruiting bodies are black spots that appear on the damaged tissue releasing spores.


Favoured Conditions

This fungus prefers a warm humid environment and leafy plants with soft new growth, particularly if they are crowded.

        

Affected Plants

There are many ornamental and native plants that are hosts to a wide range of fungal leaf spots. Some specific ones are listed below. Plants such as Cornus or Paeonia species are infected by a large variety of leaf spots, while other plants attract a specific leaf spot.

Generally a healthy plant can tolerate fungal leaf spot attack, though it may make the plant look unsightly. In trees and shrubs it is difficult to control and generally not necessary, but in perennials and annuals control may be necessary in order to save the plant.


Acalypha and Arctotis species are infected by up to three leaf spots including (Cercospora acalyphae) and (Ramularia acalyphae) that rarely require control.


Acer species are infected by Purple Eye (Phyllosticta minima) which forms spots with brownish centres and purplish margins causing the death of the leaves.


Acer species are also infected by Tar Spot (Rhytisma acerinum) which forms round black spots that have yellow margins. Not normally seen on cultivated trees, but seen in forests.


Adiantum, Asplenium, Blechnum, Cyathea, Davallia, Nephrolepis, Platycerium, Polypodium and Pteris species are infected by the leaf spot (Pseudocercopora species) which forms circular brown spots on the fronds and heavy infection can defoliate a plant.


Aesculus species are occasionally infected with the leaf spot (Septoria hippocastani) which forms small brown spots.


Agave species are susceptible to the leaf spot (Coniothyrium concentricum), which appear as greyish spots up to 20mm (1in) across with concentric rings and black fruiting bodies. Affected leaves are destroyed as the infection spreads.


Albizia julibrissin is susceptible to the fungal leaf spot (gloeosporium aletridis), which does not normally require control.


Amelanchler, Chaenomeles, Crataegus and Rhaphiolepis species Mespilus germanica are infected by the leaf spot (Fabraea maculata) which may cause considerable damage during wet periods.


Aquilegia species can be infected by three types of Leaf Spot including (Ascochyta aquilegiae), (Cercospora aquilegiae) and (Septoria aquilegiae), normally appearing during humid conditions forming spots on the leaves.


Arbutus species are infected by two leaf spots (Septoria Unedonis) which produces small brown spots on the leaves and (Elsinoe mattirolianum).


Arctostaphylos manzanita is infected by the leave spot (Cryptostictis arbuti) which damages leaves but is not normally detrimental to the shrub.


Aspidistra species are infected by the leaf spot (Colletotrichum omnivorum) causing whitish spots on the leaves and petiole.


Aster species are infected by many leaf spots including (Alternaria species), (Cercosporella cana), ( Ovularia asteris) and (Septoria asteris).


Aucuba species are infected by several leaf spots, usually as a secondary infection after aphid attack. These include (Phyllosticta aucubae) and (Phyllostica aucubae).


                     Azalea


Azalea (Rhododendron species) are susceptible to Leaf Scorch (Septoria azalea). This fungal disease forms reddish- brown spots which expand and engulf the leaf, with fruiting bodies appearing in the centre. Infected leaves die, then fall and the branchlets wilt. This problem is more serious during wet periods and may require control using a fungicide.


Banksia robur


Banksia species are infected by several leaf spots causing chlorotic areas that have brown centres and is not normally a major problem for the plant.


Betula species may be infected by the Leaf Spots (Gloeosporium betularum) that forms brown spots with darker margins and (Cylindrosporium betulae) that also forms brown spots with faded indefinite margins.


Bougainvillea species are infected by the leaf spot (Cercosporidium bougainvilleae) which forms rounded spots with dark margins that yellowish ting. Infected leaves die and fall from the plant.


Calendula species are infected by the Leaf Spot (Cercospora calendulae) which rapidly infects the plant spotting the leaves and killing the plant.


Callicarpa species may be infected by the leaf spot (Atractilina callicarpae) forming irregular brownish spot or (Cercospora callicarpae) which can defoliate the plant in subtropical climates.


Campsis species may be infected by several fungal leaf spots including (Phyllosticta tecomae), (Septoria tecomae) and (Cercospora duplicata).


Carpinus species are infected by the leaf spots (Gloeosporium robergei), (Gnomoniella fimbriata) and (Septoria carpinea), all are minor infections not normally requiring control.


Carya species are infected by several leaf spots including (Gnomonia caryae) that infects leaves with irregular reddish spots on the upper surface with corresponding brown spore producing spots on the underside. It also has a secondary spore release that occurs on the dead leaves where it over winters. Other leaf spots include (monochaetia desmazierii) and (Marssonina juglandis).


Ceanothus species are susceptible to the leaf spot (Cercospora ceanothi) and (Phyllosticta ceanothi) both are of minor importance not requiring control.


Celtis species are infected by many leaf spots including (Cercosporella celtidis), (Cylindrosporium celtidis), (Phleospora celtidis) and (Septogloeum celtidis).


Chrysanthemums species are infected by the leaf spot (Septoria species) which forms yellow spots appear toward the edge of the leaves; these become enlarged brownish patches with yellow margins.  Damaged areas may converge and in severe attacks and the leaves may fall prematurely or flower production is reduced.


Clematis species are infected by the fungal disease (Ascochyta clematidina) which may cause stem rot or leaf spots that are water soaked areas with reddish margins. The infection spreads from the leaves to the stem causing wilting and eventually girdling the stem killing the plant. There are many fungal leaf spots that infect this plant including (Cercospora rubigo) and (Septoria clematidis)


Dracaena deremensis


Cordyline and Dracaena species may be infected by the leaf spot (Phyllosticta maculicola) which forms small brownish spots that have yellowish margins and has black fruiting bodies that forms coils of spores. These plants are also susceptible to other leaf spots such as (Glomerella cincta) and (Phyllosticta dracaaaenae). Keep foliage dry to avoid infection.


Cynodon dactylon,  Pennisetum clandestinum and many other Turf Grasses are susceptible to Helminthosporium Disease.


Daphne species are infected by the leaf spot (Gloeosporium mezerei) and (Marssonina daphnes) both of which form thickish brown spots that are seen on both sides of the leaves. Infected leaves turn yellowish before dieing.


Dendranthema species are infected by many leaf spots such as (Septoria chrysanthemi) which first forms yellowish spots up to 25mm (1in) across that become black. Infected leaves die prematurely and persist on the plant.


Dianthus species may be infected by the leaf spot (Septoria dianthi). It forms light brown rounded spots that have a purplish border. The scattered spots on the lower leaves can also be found on the stems and the spores are dispersed by water from the tiny black fruiting bodies.


Dieffenbachia species are infected by several leaf spot fungi including (Cephalosporium species) and (Myrothecium species).


Eucalyptus species


Eucalyptus species are infected by many fungal leaf spots such as (Mycosphaeralla species), (Hendersonia species) and (Monocheatia monochaeta). Generally leaf spots appear on the juvenile or new leaves causing brownish spots that enlarge and may have a purplish halo around the margin.  Mature adult leaves are not normally infected and the trees rarely require control measures.


Fern species are infected by the leaf spot, (Alternaria polypodii). This fungus appears as brown circular or oblong spots that congregate along the margins of the pinnae causing the fronds to turn brown and die.  It is spread by wind currents from plant to plant and control methods include removing infected fronds and maintaining a drier atmosphere.


Ficus species are infected by various fungal leaf spot including (Pseudocercospora species). Generally the fungal attack forms circular or irregular dark coloured spots on the leaves eventually causing them to fall prematurely.


Ficus elastica is susceptible to many fungal leaf spots including (Alternaria species), (Leptostromella elastica) and (Phyllosticta roberti).


                    Strawberry


Fragaria x ananassa (Strawberry) is infected by the fungal leaf spot (Mycospharella fragariae). The mature leaf is initially infected with well defined brown spots that that turn light grey with red-purplish margins. As the spots merge they form large brown blotches and the leaf turns yellow then dies. This fungal attack normally occurs on plants in poor health and can be a serious problem early in the season seriously damaging stock.


Fraxinus species


Fraxinus species are infected by the leaf spot (Gloeosporium aridum) giving the leaf a scorched appearance as large blotches appear from the margin or apex and turn brown with a papery texture. It is more prevalent during rainy periods and infected leaves fall prematurely. Collect and depose of fallen leaves otherwise control is not normally required.


Fuchsia species may be infected by the leaf spot (Septoria species) or ( Cercospora species), both form spots with dead centres and dark margins.


Gladiolus species are infected by Hard Rot or Leaf Spot (Septoria gladioli). On the corms reddish brown circular water soaked spots become large and sunken. These areas dry out and form obvious margins. The leaves may also have these symptoms but is not commonly seen.


Hemerocallis species are infected by several leaf spots including (Cercospora hemerocallis) and (Heterosporium iridis). These may be in the form of black spots or brownish spots that converge killing the leaf. Infected leaves should be removed and burnt.


Hibiscus species


Hibiscus rosa-sinensis, Hibiscus syriacus and Hibiscus tiliaceus are susceptible to several fungal leaf spots including (Ascochyta abelmoschi), (Cerospora kellermanii) and (Phyllosticta hibiscina). All cause spotting or blotching of the leaf surface; remove and destroy infected parts.


Hydrangea species are infected by four fungal species including (Ascochyta hydrangeae), (Phyllosticta hydrangeae) and (Septoria hydrangeae).


Iris species are infected by several fungal leaf spots including (Alternaria iridicola) and (Macosphaerella species).

Iris species are also infected by the leaf spot (Didymellina macrospore) that forms greyish spots with brown water soaked borders and coalesce on the upper part of the leaf. This casual organism commonly occurs after flowering killing the leaves but will not infect the bulbs. The bulbs become weak over several seasons due to the decreased foliage.

There is also a Bacterial Leaf Spot (Bacterium tardicrescens) that is commonly mistaken as a fungal problem causing translucent spots that coalesce and involve the entire leaf. Normally found on Iris species.


Laburnum anagyroides is infected by the Leaf Spot (Phyllosticta cytisii). The leaf forms light grey spots with no definite margin and mature to brown. The black fruiting bodies appear as dots in the centre of the spot.


Leucanthemum species are infected by the leaf spot (Cerocspora chrysanthemi) and (Septoria leucanthemi).


Magnolia species are susceptible to many species including (Alternaria tenuis), (Mycosphaerella milleri) and (Phyllosticta species). Leaves generally turn brown from the apex or margins turning brown or spots appear on the leaf surface and leaves become yellow before withering and dieing. Normally the make the tree look poorly but have little effect on its growth. Control is not normally required.


Nerium oleander is susceptible to several fungal leaf spots including (Cercospora nerella), (Cercospora repens), (Gloesporium species) and (Phyllosticta nerii). Infected leaves should be removed but generally control is not required.


Nyssa sylvatica is infected by the leaf spot (Mycosphaerella nyssaecola) forming irregular purplish blotches.


Orchids such as Cattleya, Cymbidium, Cypripedium, Dendrobium, Epidendrum, Paphiopedilum, Phalaenopsis and Zygopetalum species are infected by several leaf spots including (Cerospora, Colletotrichum and Phyllosticta species). Normally forming dark or dead, circular or irregular areas on the leaves.


Palms such as Syagrus, Howea, Phoenix, Roystonea and Washingtonia species are infected by Leaf-scab (Graphiola phoeicis).


Palms such as Archontophoenix, Caryota, Chamaedorea, Cocos, Dypsis, Howea, Liculia, Linospadix, Livistona, Phoenix, Ptychosperma, Rhapis, Roystonea, Syagrus, Washingtonia and Wodyetia species are susceptible to several fungal leaf spots including;

(Bipolaris spp.), (Cylindrocladium spp.), (Colletotrichum spp.) and (Pestalotiopsis spp.).


Generally the circular leaf spots are brown and may have a yellow halo such as Palm Ring Spot (Bipolaris incurvata). They vary in size from small to large depending on the species. When a plant is healthy it recovers from attack, but heavy infections can defoliate, causing the collapse of the plant.


Palms are also infected by the Brachybasidium Leaf Spot (Brachybasidium pinangae). This fungus forms angular leaf lesions that produce fruiting bodies on the underside and is commonly found on Archontophoenix species.


                  Archontophoenix cunninghamiana


Passiflora species are infected with many types of leaf spot such as (Alternaria passiflorae).


Phoenix species are susceptible to False Smut (Graphiola phoenicis). This fungus forms yellow leaf spots that become hard with a raised with a blackish scab, which produces masses of powdery spores that are thread-like.


                  Pittosporum species


Pittosporum species are susceptible to the leaf spots (Alternaria tenuissima), (Phyllostica species) and (Cercospora pittospori). Circular or angular dark spots appear on the leaves and are surrounded by necrotic areas that are yellowish. Generally removal of infected leaves is adequate control.


Poa species and other cool season grasses are infected by Winter Fusarium Leaf Disease (Fusarium species), which causes small pale spots that are water soaked to appear on the leaves that turn red-brown. Infected leaves become bleached then wither and die, but the infection will not affect the crown or roots of the plant. It can be identified by pink, cotton-like mycelium and the plant prefers cold wet weather.


Populus species are infected by several fungal leaf spots including (Ciborinia bifrons, Ciborinia confundens), and (Mycosphaerella populicola).


Prunus species are infected by several leaf spots including (Cercospora circumscissa and Septoria ravenelii).


Pseudotsuga menziesii Douglas Fir is infected by the Leaf Cast (Rhabdocline pseudotsugae) Symptoms include the needles becoming yellowish at the apex and extending down the needle and spreading to others during moist spring weather turning them brown. Brownish scorched areas are noticeable on the tree from a distance. Control; is not normally required for mature trees but nursery stock may require spraying with a copper based fungicide.  


Psidium guajava (Guava) is infected by (Glomerella cingulate). This fungus courses spots to appear on leaves and mummifies and blackens immature fruit or rots mature fruit.  This fungus can devastate a guava crop.  


Quercus species are infected by several types of leaf spot including (Cylindrosporium microspilum) and (Marssonina martini). These attacks tend top take place later in the season and normally not detrimental to the tree.


Rhododendron species are infected by a large variety of fungal leaf spots including (Cercospora rhododendri) and (lophodermium melaleucum)


Salix species are infected by several fungal leaf spots including (Ascochyta salicis) and (Septogloeum salicinum).


Senecio species are infected by the fungal leaf spot (Alternaria cinerariae) and (Cercospora species), forming dark rounded or angular spots.


Spiraea species are attacked by the fungal leaf spot (Cylindrosporium filipendulae).


Stenotaphrum secundatum (Buffalo) turf grass is susceptible to Grey Leaf Spot (Pyricularia grisea) in domestic and commercial situations devastating lawns. This fungal disease infects the stems and leaves with small brown lesions that enlarge rapidly forming grey-brown spots that have darker borders or surrounded by yellow chlorotic areas. This infection is commonly found on newly laid turf but will also infect established lawns. It is most prevalent during warm humid periods in soil with a high nitrogen level.


Syringa species are attacked by up to six species of leaf spot including (Cercospora lilacis) and (Phyllostica species).


Syzygium species


Syzygium species are infected by fungal leaf spots but normally control is not required.


Tagetes species are infected by the leaf spot (Septoria tageticola), which starts at the base and moves progressively up through the plant, covering the leaves in grey to black spots.


Trillium species are host to several leaf spots, including (Colletotrichum peckii) (Gloeosporium Trillii) (Heterosporium trillii).


Ulmus species are infected by many fungal leaf spots including (Gnomonia ulmea) and (Cercospora sphaeriaeformis).


Veronica species are infected by the leaf spot (Septoria veronicae). The symptoms include small violet to brown spots appear on the upper surface of the leaf and correspondingly yellowish brown on the underside. The spots converge forming a scorched shot-hole appearance and eventually death of the leaf.


Vaccinium ovatum


Vaccinium ovatum is infected by the leaf spot (Rhytisma vaccinii) and (Dothichiza caroliniana).


Vicia species are infected by the leaf spot (Erostrotheca multiformis), which forms greyish spots that enlarge and may defoliate the plant.


Wisteria species are infected by three fungal leaf spots (Phyllostica wisteriae), (Septoria wisteriae) and (Phomatospora wisteriae).


Non-chemical Control

Remove and destroy infected plant material and avoid overhead watering.  When planting select infection resistant varieties. Practice crop rotation and add pot ash to the soil to decrease the plants venerability to the disease. Many species of fungus overwinter in fallen leaves, remove and destroy any litter under the plant.  

Winter Fusarium Leaf Disease in Turf Grasses can be minimised by aerating the soil, reducing thatch and avoid excessive nitrogen in the soil.


Chemical Control

Protective fungicides such as zineb or copper oxychloride should be sprayed at the first sign of infection and cuttings should be sprayed as they start to grow.

Note

Always read the label for registration details and direction of use prior to application of any chemicals.


Leaf to 100 mm (4 in) long
Flower to 65 mm(2 1/2 in) wide
Inside flower
Bark

Plant Photo Gallery - Click thumbnails to enlarge

Climate zone

This Plant tolerates zones 4-10

Average Lowest Temperature : -10º C 14º F

USDA : 4, 5, 6, 7, 8, 9, 10

This USDA (United States Department of Agriculture) hardiness zone chart can be used to indicate a plant’s ability to withstand average minimum temperatures. However, other factors such as soil type, pH, and moisture, drainage, humidity and exposure to sun and wind will also have a direct effect on your plant’s survival. Use this chart only as a guide, always keep the other factors in mind when deciding where, when and what to plant.

A plant's individual USDA zone can be found in the Plant Overview.

Climate Description

Cool to Cold
These zones have low winter temperatures with moderate humidity and moderate summer temperatures.
Frosts and snow are severe. Droughts rarely occur and wind is cold.

Plant growth

Endemic native and exotic cool climate plants grow well within these zones.

Glossary

Dictionary Growth Habit
Leaf Type Botanic Flower Description
Leaf Shape Flower Inflorescence
Leaf Arrangement Fruit Type
Leaf Margin Bark Type
Leaf Apex And Bases Flower Description