ALBIZZIA 481 



Distribution and uabitat. The sub-Himalayan tract from Nepal east- 

 wards, eastern Himalayan valleys up to 2,000 ft., Assam, Chittagong, and 

 Burma. The tree is often planted along avenues and in gardens outside its 

 natural region, and grows well in Dehra Dun and other stations of northern 

 India. It is found wild as a rule along the banks of streams and in moist 

 places. In Burma it occurs in tropical forests where many of the species are 

 evergreen, in lower mixed forests of the alluvial plains, and also in upper 

 mixed deciduous forests. 



In its natural habitat the absolute maximum shade temperature varies 

 from 98 to 108 F., the absolute minimum from 35 to 55 F., and the normal 

 rainfall from 45 to 200 in. or more. 



Leaf-shedding, flowering, and fruiting. The tree is leafless or nearly 

 so for a short time in the early part of the hot season, about March ; the 

 leaves usually turn yellow before falling. The yellowish white flow^ers appear 

 in April-May. The pods become full-sized about October-November, but are 

 then unripe and green or reddish green ; they ripen from February to April 

 (observed ripening February in Bengal Duars, April in Dehra Dun). When 

 ripe (Fig. 183, a) they are 4-8 in. long by 0-7-1 in. broad, light brown, fiat, 

 the seeds prominent. Most of the pods fall during the hot season, and dehisce 

 as a rule after falling : they are carried by wind, with the seeds enclosed, to 

 some distance from the tree. Some dehisce on the tree and a few of the open 

 pod-valves may remain hanging as late as the following November. The 

 seeds (Fig. 183, b) are 0-3-0-4 in. long, broadly elliptical or orbicular, light 

 brown, flat, smooth, with a leathery testa : about 550-600 weigh 1 oz. The 

 seeds germinate readily, but so far as tests at Dehra Dun go thej'' appear to 

 lose their vitality more quickly than those of other species of Albizzia. 



Germination (Fig. 183, c-g). Epigeous. After the emergence of the 

 radicle the hypocotyl arches, soon straightening and carrying the cotyledons 

 above ground : as a rule the testa is carried up over the cotyledons, falling 

 off with their expansion. 



The seedling (Fig. 183). 



Roots : primary root moderately long, terete, tapering, flexuose : lateral 

 roots moderate in number, fibrous, distributed down main root. Hypocotyl 

 distinct from and thicker than young root, 1-2-1 -8 in. long, terete, tapering 

 slightly upwards, green, minutely pubescent. Cotyledons sub-sessile, 3-5-5 in. 

 by 3-4 in., plano-convex, fleshy, elliptical orbicular, base sagittate, entii'e, 

 glabrous, greenish yellow. Stem erect, wiry to woody. Leaves, first pair 

 opposite, produced after a very short internode, thus emerging from between 

 the cotyledons, subsequent leaves alternate. First pair simple or paripinnate 

 with two or three pairs of leaflets or imparipinnate with five leaflets or 

 bipinnate, one of the leaves often differing in form from the other. Simple 

 leaves with petiole 0-1 in. long, lamina 0-8-1-2 in. by 0-3-0-4 in., ovate or 

 elliptical lanceolate, acuminate, entire, giabrescent or minutely pubescent. 

 Earliest compound leaves with rachis 0-5-0-8 in. long, leaflets opposite, verj- 

 shortly petiolate, 0-5-0-8 in. by 0-2-0-4 in., ovate lanceolate, acuminate. 



Seedlings raised at Dehra Dun showed only moderate growth during the 

 first two years, nursery-raised transplants having a maximum height of 5| in. 

 and 14 in. by the end of the first and second seasons respectively. The 

 seedlings proved very sensitive to drought, and grew best if well watered and 

 kept shaded from the sun. 



2307.2 T 



