Common names: SCREWBEAN, FREMONT SCREWBEAN, SCREWPOD MESQUITE,
(_TORNILLO_)
Arizona, Texas, and California deserts: (_Prosopis pubescens_).
Yellow. May-June.
Pea family. Size: Shrub, or tree up to 20 feet.
Although the Screwbean, so called because of the tight spiral curl
formed by the seed pod, is not as common as Honey Mesquite, it is nearly
as widespread, being found below 4,000 feet from western Texas to
southern Nevada, and southern California to northern Mexico. The
majority of the trees are small and shrubby.
Fruits, in common with those of Honey Mesquite, are used by Indians and
livestock for food. Bark from the roots was used by the Pima Indians to
treat wounds. Where abundant, the wood is used for fence posts, tool
handles, and fuel. Birds, particularly the Crissal Thrasher, make use of
the shreddy bark for nest-lining material.
Where Screwbean and Honey Mesquite grow together, they may be
distinguished in the winter when trees are leafless and fruits have
fallen or been removed by animals, by the gray-barked twigs of the
Screwbean, those of the Honey Mesquite being brownish red.
Some botanists prefer to classify Screwbean as genus _Strombocarpa_.