Horse Bean or Retama TreeThe Horse Bean, or Retama (Parkinsonia aculeata, Linn.). native to the valleys of the lower Rio Grande and the Colorado, is a small, graceful tree with drooping branches, which are clothed with strong spines, long leaf stems set with many pairs of tiny leaflets, and bright yellow, fragrant perennial flowers.
In the tropics the tree is ever-blooming. In Texas it rests only in midwinter. The pods are long, and constricted between the seeds. As an ornamental hedge plant this tree has no equal in the Southwest.