Annual, biennial or short-lived perennial native legume with purple, yellow or white flowers, blooming April to August. Vigorous grower with a deep taproot, occurs on dry open slopes and recently disturbed sites, from lowlands to mountain habitats; up to 10,000 ft. elevation. Prefers well-drained sandy to coarse soils. Seeds are eaten by various birds. Important pollen source for bees and other pollinators. Poisonous to livestock.