Japan Flora: Perennial herb pubescent while young; stems slender, ascending or decumbent at base, 40-80 cm. long, 3-angled, usu­ally with a wing 0.5-2 mm. wide on 2 angles or nearly wing­less; leaves short-petioled, the stipules lanceolate to narrowly ovate, bifid, the leaflets rather membranous, lanceolate to nar­rowly oblong, 3-5 cm. long, 8-15 mm. wide, pale green to glau­cous and usually pubescent beneath, glabrous above, the ten­drils 2- or 3-branched; flowers very similar to those of the preceding; legumes linear-oblong, flat, 4-5 cm. long, 7-8 mm. wide, glabrous. May-Aug. Wet grassy places in lowlands. 

Hokkaido, Honshu, Kyushu (Tsushima). Sakhalin, Ku­riles, Korea, and widely distributed in the N. Hemisphere.