Alnus nepalensis D.Don

Family Description

Monoecious, deciduous trees or shrubs. Leaves alternate, simple, stipulate. Male flowers in pendulous, bracteate catkins, perianth minute, 4-fid or absent, stamens 2-20; female flowers in erect or catkinate, bracteate spikes or in clusters, perianth minute or absent,ovary superior or inferior, 2-locular, styles 2,simple, ovules usually 1 per cell, pendulous. Fruit a winged achene borne in a catkin, or nut like and enclosed in a bract in a bract borne in spikes or clusters.

Genus Description

Trees. Leaves elliptic, entire or serrulate. Male catkins in terminal panicles, linear, pendulous; bracts 3-lobed, each bearing 3 flowers; perianth 4-toothed; anthers 4. Female spikes erect, 6-10 in axillary racemes below male inflorescence, linear and rigid when young; each bract beering 2 flowers; perianth absent, styles 2, short. Fruiting spikes becoming ovoid-ellipsoid, cone- like, with woody, persistent scales. Fruit a compressed achene with 2 minute wings.

Species description

Tree up to 20m. Leaves broadly elliptic, 9-15 x 4-9cm, acute,base rounded or cuneate, minutely brown-glandular beneath, pubescent on veins; petiole 1-2cm; stipules oblong, 1cm auriculate. Male catkins 5- 7 x 0.3-0.4cm. Female spikes 1 x 0.2cm when young, becoming 1.5 x 0.8 when mature; scales obpyramidal, 3 mm. Achenes triangular, embryo elliptic, bearing wings 1 mm at each side of apex.