Tree with a spreading crown and deeply ridged dark brown bark. Spines on branchlets are straight, about 0.5-5 cm long, solitary or paired. Leaves are compound, about 3-11 cm long, ending in a short stipe. Leaflets are sessile, 6-23 mm long and 3-5 mm broad, rounded at the base and apex, 6-29 pairs arranged in opposites on the axis. Flowering inflorescences are yellow, rod-like, up to 15 cm long, and many-flowered. Pods are leathery, flattened, pale yellow, smooth and fleshy, up to 30 cm long, 1.5 cm wide and 4-10 mm thick, with a few seeds.
Sandy areas of dry zone.
Fast growing. Tolerates flood conditions. Very difficult to control spread. An invasive alien species of national importance. Introduced from tropical America to arid zones to increase green cover.