SafePlants

Snake River Milkvetch (Astragalus purshii var. ophiogenes)

The Snake River milkvetch, scientifically known as Astragalus purshii var. ophiogenes, is a variety of milkvetch native to the Snake River region.

Considerations for Pets

• This plant is a type of milkvetch, and the text refers to its seedpods (legumes).

Taxonomy and Nomenclature

• Scientific Name: Astragalus purshii Douglas ex Hook. var. ophiogenes (Barneby) Barneby
• Common Names: Snake River milkvetch, woollypod milkvetch, Pursh's milkvetch, Pursh loco, Pursh's milk-vetch
• Family: Fabaceae (Legume family)
• Synonym: Astragalus ophiogenes
• Other Astragalus Species Mentioned: Astragalus oniciformis (Picabo milkvetch), Astragalus paysonii (Payson's milkvetch), Astragalus riparius (Piper's milkvetch), Astragalus cusickii var. packardiae (Packard's milkvetch), Astragalus mulfordiae (Mulford's milkvetch), Astragalus filipes (Threadstalk milkvetch), Astragalus atratus var. owyheensis, Astragalus curvicarpus (Curved Milkvetch), Astragalus lentiginosus var. coachellae (Coachella Valley milk-vetch).

Distribution and Habitat

• Native to Oregon and Idaho, particularly the Snake River Plain and its canyons.
• Picabo milkvetch (Astragalus oniciformis) is specifically found north of the sagebrush-steppe ecosystem on the Snake River Plain.
• Painted milkvetch is found in the upper Snake River Plains of southeast Idaho and adjacent Montana.
• Mulford's milkvetch is native to the Snake River Plain.

Ecological Role

• Basalt milkvetch is a nitrogen-fixing member of the Pea family.

Morphological Characteristics and Growth Habits

• Snake River milkvetch is a forb/herb and a perennial plant.
• Sterile milkvetch is distinguished by its low, freely branching growth from creeping rhizomes (versus the single stout vertical taproot).

Flower Description

• Racemes with 5-11 flowers.
• Petals are pink or pink-purple.