Greene's deerweed, Greene's bird's-foot trefoil
Southeast Arizona and southwest New Mexico
Dry, rocky slopes and mesas; 3,000 to 7,000 feet
A few inches - grows along the ground
Divided into 3 to 7 obovate to elliptic leaflets, less than half an inch long; on short stalks
Acmispon greenei is found over a relatively small area, in southeast Arizona and far southwest New Mexico. Plants are prostrate, and the stems are short, less than one foot long, though many plants often grow together to form an extensive mat. Leaves, stems and calyces are hairy, the hairs soft, quite long, and spreading, colored grey or light brown. Leaves are palmately divided into small, obovate leaflets, most commonly 3 or 4. Leaflets are usually pointed at the tip.
Flowers form singly or in clusters of up to four (usually two), borne on a stalk up to one inch long. The lobed part of the calyx is equal in length to the unlobed section, or lightly longer. The banner petal is yellow on the upper surface and orange-pink on the underside; a useful identifying characteristic of this species. Petals in bud are bright red. The fruit is a linear, sparsely hairy pod, a little less than one inch long, colored reddish brown. Flowers generally appear in spring, but sometimes again in late summer.