LEGUMINOSAE 



Catclaw Acacia. Paradise Flower 

 Acacia greggii Gray 



HABIT. A shrub or small tree rarely 30 feet high and 10-12 

 inches in diameter; trunk short; crown irregular. 



LEAVES. Alternate; evenly doubly pinnate; 1-3 pairs of 

 pinnae, each with 4-5 pairs of obovate, obtuse, thick, pubescent 

 leaflets Vf6~/4 inch long; persistent; petiole short, glandular 

 near middle; stipules linear, caducous. 



FLOWERS. Nearly regular; perfect or polygamous; frag- 

 rant; in dense, pubescent spikes; calyx 5-lobed, puberulous; 

 corolla 5-petaled, bright yellow, Yq inch long; stamens numer- 

 ous, exserted, |4 inch long; ovary stalked and hairy. 



FRUIT. Linear-oblong, flat, much-curved and contorted, 

 indehiscent, light brown legume 2-6 inches long and }/i-% inch 

 wide; contracted between the seeds; valves thin and mem- 

 branaceous. Seed: compressed, dark brown, lustrous, i4 inch 

 long. 



TWIGS. Slender; angled; puberulous or glabrous; pale 

 brown; armed with stout, broad, recurved, infrastipular spines 

 H inch long, giving tree its common name. 



BARK. Thin {Y^ inch); furrowed and scaly; light gray- 

 brown; astringent. 



WOOD. Very heavy; hard; strong; close-grained; durable; 

 ring-porous; heartwood red-brown; sapwood thin, light yellow. 



SILVICAL CHARACTERS. Lower Sonoran zone; intoler- 

 ant; vigorous reproducer; thrives in driest and poorest soils; 

 on dry mesas, plains, and in low canyons. 



Eight other species of Acacia may reach tree size in the South- 

 west : 



1. A. amentacea DC, with long spines, yellow flowers in spikes, and 

 a flattened arcuate legume; southwestern Texas. 



2. A. angustissima Kuntze, with no spines, white flowers in capitate 

 heads, and flat legume; New Mexico and Texas. 



3. A. constricta var. paucispina Woot., with long spines, yellow flowers 

 in capitate heads, and a terete legume; Texas to Arizona. 



4. A. emoryana Benth., with short spines, flowers in short spikes, and 

 flat, hairy legume with thickened sutures. 



5. A. farnesiana (L.) Willd., with spines, yellow flowers in capitate 

 heads, and a terete legume; Texas. 



6. A. millefolia S. Wats., with slender or no spines, cream-colored 

 flowers in racemes, and a very flat pod; rare in southern Arizona 

 and Mexico. 



7. A. tortuosa Wifld., like No. 5 but with longer pod (3-5"); Texas. 



8. A. wrightii Benth., yellow flowers in spikes; short spines; Texas. 



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