Distribution: Widely distributed throughout Washington; widely distributed throughout much of North America.
Habitat: Roadsides, fields, lawns, wastelots, and other disturbed areas, often on sandy or gravelly soil.
Flowers: April-August
Origin: Introduced from Eurasia
Growth Duration: Annual, Perennial
Conservation Status: Not of concern
Pollination: Bumblebees, flies, butterflies
Finely villous annual, the stems 1-4 dm. long, decumbent to erect.
Leaves trifoliate, leaflets elliptic-obovate, 0.5-2 cm. long; stipules entire to shallowly fine-toothed,
Inflorescence a dense, spike-like raceme 0.5-1 cm. long, the peduncles arising in the leaf axils; flowers pea-like, 10-40, yellow, 2-3 mm. long, the banner erect, much longer than the wings and keel; calyx nearly as long as the corolla, the 5 equal teeth longer than the tube.
Pod 1-seeded, 2-3 mm. long, curved almost in a spiral, turning black at maturity.
PNW Herbaria: Specimen records of Medicago lupulina in the Consortium of Pacific Northwest Herbaria database
WA Flora Checklist: Medicago lupulina checklist entry
OregonFlora: Medicago lupulina information
E-Flora BC: Medicago lupulina atlas page
CalPhotos: Medicago lupulina photos