Northern Sweetvetch ranges from the Canadian arctic tundra into the southern Rockies. It is fairly common in the high plains, especially in the Rocky Mountain region, where it grows in fine textured, often clayey soils. It flowers in early summer or late spring. This species is not poisonous and, in fact, was historically collected and eaten by Indians. The roots especially are tasty (licorice-like) and nutritious.
Reference: Sagebrush Country: A Wildflower Sanctuary