114 



Bulletin of the University of Texas 



North Carolina to Florida and Texas. Planted throughout 

 its range as an ornamental tree. 



MIMOSACEAE. The Mimosa Family. 



Trees with alternate compound evenly pinnate leaves and 

 small leaflets. Fruit a bean-like pod. 



Leaves with 1 to 2 pairs of pinnae. 



Leaflets 5 to 8 pairs, pods tightly twisted 



Leaflets 12-20 pairs, pods not twisted 



Leaves 2 to 3 pairs of pinnae, leaflets numerous. . 

 Leaves with 1 to 4, 2 to 3 or 3 to 4 pairs of pinnae. 



Leaves with 3 to 5 pairs of pinnae 



Leaves with 3 to 8 pairs of pinnae 



Leaves with 2 to 20 pairs of pinnae 



1. Strombocarpa. 



2. Prosopis. 



3. Siderocarpos. 



4. Acacia. 



5. Havardia. 



6. Vachellia. 



7. Leucaena. 



1. STROMBOCARPA. Screw Bean. 



1. Strombocarpa odorato (Torrey) A. Gray. Screw Bean. 

 A shrub or small tree with thick, shaggy, light brown bark, 

 and reddish brown branches which are armed with axillary 

 spines. Leaves bipinnate mostly with 1 pair of pinnae, some- 

 times 2 pairs. Flowers in slender, stalked, axillary spikes. 

 Fruit a twisted cylindrical pod. 



2. PROSOPIS. The Mesquites. 



1. Prosopis glandulosa Torrey. Mesquite. A low, round 

 topped tree with thick, reddish brown, fissured bark, yellow- 

 ish green twigs and darker branches which <ire frequently 

 armed with axillary spines. The leaves are bipinnate with 1 

 to 2 pairs of pinnae; leaflets numerous. Flowers perfect, 

 borne in slender, green or yellowish spikes. Fruit a straight 

 or slightly curved indehiscent pod. 



Mexico north to Nevada, Kansas, Texas and California. It 

 has gradually encroached on the grassy plains and frequently 

 forms dense shrubbery thickets. 



The wood is heavy, very hard, close grained, dark red in 

 color, very resistant in contact with the soil, takes a beauti- 

 ful finish. It is used for furniture, ornaments, gun stocks, grill 

 work, posts and fuel. The beans are used for food. 



