Stems 0.5-1.5(-2) dm. Basal leaves: petiole 0.5-2.5(-3.5) cm; blade oblanceolate to obovate in outline, 0.3-1.5(-2) cm × 2-4(-7) mm, margins usually lyrate-pinnatifid, rarely dentate or entire; lateral lobes obtuse. Cauline leaves 0-4; blade linear to oblong. Fruiting pedicels 3-7 mm. Flowers zygomorphic ; sepals 0.5-0.8 (-1) × 0.4-0.6(-0.8) mm; petals oblong to obovate, abaxial pair 1.5-2.5 × 0.6-1 mm, adaxial pair 0.5-1 × 0.3-0.4 mm; stamens 6, tetradynamous; filaments 0.8-1 mm, (basal appendage white, ca. 1/2 its length); anthers 0.1-0.2 mm. Fruits 3-4.5 × 3-4.5 mm; style ca. 0.1 mm. Seeds 1-1.2 × 0.9-1 mm. 2n = 36. Flowering Apr-Jun. Sandy areas along trails, near beaches, pine clearings, waste grounds, fields, roadsides, gravelly slopes; 0-300 m; introduced; B.C.; Calif., Conn., Md., Mass., Mich., N.J., N.Y., N.C., Oreg., Pa., S.C., Va., Wash.; Europe; Asia (Middle East); introduced also in South America (Chile), nw Africa, Australia.