Astragalus mollissimus (common name - wooly locoweed) is a perennial plant in the legume family (Fabaceae) found in the Colorado Plateau and Canyonlands region of the southwestern United States.[1]
It is hairy a perennial plant growing from 2inchesto34inchesin (toin) tall, from a very short stem.[1]
It has hairy stems and leaves.[1] "Mollissumus" means "most soft", referring to the hairy covering of the leaves and stems.[1] Pinnate leaves are from NaNinchesto11inchesin (toin) long, with 15–35 elliptical to oval wooly leaflets.[1]
It blooms from March to August.[1] The inflorescence are from NaNinchesto10inchesin (toin) stalks with 7–20 flowers per stalk.[1] Each pink to purple or bicolored with white flower has a NaNinchestoNaNinchesin (toin) hairy calyx with 5 pointed teeth, around a NaNinches corolla with upper petal flares at the end.[1] The inflated seed pods are NaNinchesto1inchesin (toin), egg shaped and hairless to densely hairy.[1]
It grows from grasslands to Pinyon juniper woodland communities ranging from Wyoming to Arizona.[1]
The plant derives its common name from its wooly stems and leaves, and its effect on the nervous system of livestock which consume it, causing them to "go loco." This is caused by an alkaloid it contains called swainsonine, formerly known as locoine.[2] [3] The plant is toxic both fresh and dried, and in addition to its effects on the nervous system, can also cause congenital defects and liver damage in livestock.