Lead Tree 



527 



are evenly bipinnate, i to 2 dm. long, including the slender leaf-stalk, which is 

 provided with a gland at the top or about 

 midway from the base; there are 10 to 20 

 pairs of pinnae, 3 to 5 cm. long and short- 

 stalked; the leaflets, 15 to 30 pairs, arc 

 closely placed, linear, about 5 mm. long, 

 bluntly pointed, oblic^ue, and nearly or quite 

 sessile, somewhat hairy at first, becoming 

 pale, hght green and smooth. The flow^ers 

 appear during spring and summer on the 

 new growth in axillary clusters of 2 to 4, 

 long-stalked, globose heads 1.5 cm. in di- 

 ameter, which are woolly before the flowers 

 open; the bell-shaped calyx is i to 1.5 mm. 

 long, obtusely 5-lobed and slightly hairy; 

 petals about three times the length of the 

 calyx, hnear-spatulate, and sharp-pointed; 

 the 10 stamens are scarcely twice the length 

 of the petals ; ovary nearly sessile and hairy. 

 The fruit is flat, hnear, often variable in 

 length in the same cluster, from i to 2 dm. 

 long, about 2 cm. wide, usually 2 or 3 in a cluster on a thickened stalk, rounded 

 and tipped by a short point, tapering obhquely at the short-stalked base, brown 

 and shining, sphtting into thin leathery valves, 16 to 28 seeded; seeds obovate, 7 

 mm. long, dark brown and shining. 



The wood is hard, close-grained, dark brown, with yellowish sapwood; its spe- 

 cific gravity is about 0.67. It is occasionally sawed into lumber and apphed to 

 ordinary local uses. 



Its rapid growth, profusion of flowers, and beautiful feathery foliage recom- 

 mend it as an ornamental and shade tree for the southern portion of our area. 

 It is also called the Chalky Leucaena. 



Fig. 4S7. Mexican Lead Tree. 



2. LEAD TREE Leucaena glauca (Linnaeus) Bentham 

 Mimosa glauca Linnasus 



A shrub, rarely becoming a slender tree 10 meters tall, with a trunk diameter 

 of I dm. It occurs in sandy soil in peninsular Florida, and is native and widely 

 distributed in the American tropics whence it was introduced; it is also natural- 

 ized in the Philippine islands. 



The bark is about 10 mm. thick, dark brown, somewhat ridged and broken into 

 short, persistent scales. The twigs are sHghtly hair}' at first, soon becoming 

 smooth, dark or grayish brown. The leaves are evenly bipinnate, i to 3 dm. 

 long, including the stout, round petiole which is 3 to 6 cm. long, with an enlarged 



