Astragalus agrestis

About

Astragalus agrestis is a species of milkvetch known by the common names purple milkvetch, purple loco, and field milkvetch. It is native to much of western and northern North America from most of Canada to the southwestern United States, as well as northern Asia. It grows in vernally moist areas such as meadows, and is often found in sagebrush.

Summary from Wikipedia