Distribution: Occurring in the east end of the Columbia River Gorge in Washington; Washington to California, east along the southern U.S. to eastern North America, also in the Hells Canyon area in Idaho.
Habitat: Roadsides, wastelots, and other disturbed, open areas.
Origin: Introduced from Eurasia
Conservation Status: Not of concern
Annual, the stems 1-4 dm. long, prostrate to nearly erect, conspicuously soft-hairy.
Leaves trifoliate, the leaflets obovate or obcordate with a wedge-shaped base, 1-1.5 cm, long, not spotted, denticulate at the apex; stipules entire.
Flowers 2-5 on fairly short peduncles arising from the leaf axils; calyx 3 mm. long, the 5 teeth slightly longer than the tube; corolla pea-like, yellow, 4-5 mm. long, the banner erect, much longer than the wings and keel.
Pod spirally coiled, the margins narrowly keeled, with two rows of divergent, hooked prickles up to 3 mm. long.