LEGUMINOSAE 



Me S QUITE 

 Prosopis juliflora (Sw.) DC. [Prosopis chilensis (Mol.) Stuntz.] 



HABIT. A shrub or small tree rarely 20 feet high and 6-8 

 inches in diameter; trunk short; crown loose and straggling. 



LEAVES. Alternate; evenly, doubly (rarely 3-4) pinnate; 

 pinnae with 12-30 linear to linear-oblong, small, deciduous, 

 glabrous leaflets Vi-^ inches long; petioles glandular and spine- 

 tipped; stipules membranaceous, deciduous. 



FLOWERS. Nearly regular; perfect; fragrant; minute; in 

 spikes lV^-4 inches long; green-white; stamens 10. 



FRUIT. Linear, flat to subterete, indehiscent, yellowish, 

 straight or falcate legume 4-9 inches long and Yi-Vz inch wide; 

 edible. Seed: oblong, compressed, light brown, H inch long. 



TWIGS. Slender; round; smooth; yellow-green becoming 

 darker; usually with spines |/^-2 inches long. Winter buds: 

 terminal absent; lateral small, obtuse, dark brown, 



BARK. Thick; dark red-brown; furrowed and scaly. 



WOOD. Very heavy; hard; close-grained; not strong; very 

 durable; ring-porous; heartwood dark brown or red; sapwood 

 clear yellow, thin; used for posts, fuel, etc. 



SILVICAL CHARACTERS. Intolerant; long-lived; adapted 

 to desert sites by huge taproot descending 40-50 feet; abun- 

 dant seeder; aggressive; confined to areas below 6,000 feet. 



GENERAL. Screwbean mesquite, Prasopis pubescens Benth., 

 ranging from Texas to California and north into Nevada and 

 Utah, is readily distinguished by its thick, linear, indehiscent, 

 pale yellow legume 1-2 inches long, which is twisted by 12-20 

 turns into a narrow, straight spiral. 



* * * 



Mimosa. Silktree 



Albizia julibrissin Durazz. 



A handsome ornamental which is widely planted and has 

 escaped from Maryland to Indiana and south. The powder puff 

 appearance of the flowers is distinctive. 



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