Description from Flora of China
Herbs annual, 30-150 cm tall, villous or sericeous, or puberulent to glabrous. Stem climbing, much branched. Leaves paripinnate, 3-6 cm; stipules lanceolate to semitruncate or bifid to semihastate, 7-12 mm; leaflets 4-12-paired, linear to oblong or lanceolate, 10-30 × 3-7 mm, apex obtuse, acute, or acuminate, mucronate; lateral veins dense or not obvious; tendril 2- or 3-branched. Raceme shorter than to slightly longer than leaf, 10-30-flowered. Calyx obliquely campanulate, unequally toothed; lower teeth equaling or longer than tube or all teeth shorter than tube. Corolla purple-blue, purple, light purple, light red, light blue, or rarely white, 10-18 mm; standard linear or oblong, constricted at middle; wings shorter than standard and longer than keel. Legume oblong or oblong-rhomboid, 20-40 × 4-12 mm, apex beaked. Seeds 2-8, globose or oblate-globose, ca. 3 mm in diam. Fl. and fr. Apr-Oct. 2n = 14, 28.
Cultivated and possibly naturalized; scrub, streamsides, farms, fields and field margins, roadsides; near sea level to 1800 m. Gansu, Guangdong, Guizhou, Hebei, Hunan, Jiangsu, Nei Mongol, Shandong, Taiwan, Xinjiang, Zhejiang [native to N Africa, C and SW Asia, N Atlantic islands (Canary Islands), and Europe; widely introduced and naturalized elsewhere].