Japan Flora: Stems sometimes woody at base, 100-180 cm. high, erect to arching above, short appressed-pilose while young; stipules small, subulate; leaflets narrowly oblong, sometimes elliptic or ovate, 3-5 cm. long, 1-2.5 cm. wide, usually acute, glabrous on upper side, with short appressed hairs beneath; racemes usually longer than the leaves, the bracts and bracteoles broadly lanceolate or narrowly ovate, small, acute; flowers 15-18 mm. long, rose-purple; legumes narrowly obovate to oblong, 10-13 mm. long, 4-5 mm. wide, appressed-pilose. June-Sept.
Widely cultivated in our area; spontaneous in Honshu (Hokuriku and Chugoku Distr.). Reported to be spontaneous in China; very variable.
f. Angustifolia (Nakai) Ohwi. Leaflet pilose above; flowers rose-purple. Spontaneous in Honshu, Shikoku, Kyushu. Korea and Manchuria.
cv. Albiflora. Leaflets thinly appressed-pilose on upper side; flowers whiter Long cultivated as an ornamental.
cv. Versicolor. With white and rose-purple flowers on the same plant. Cultivated.
var. obtusifolia (Nakai) Ohwi. Branches and sometimes racemes with spreading hairs; leaves glabrous on upper side. Aug.-Sept. Honshu (Uzen, Harima Prov. and elsewhere) ; often cultivated. Forma pilosella Ohwi. Uwage-ki-hagi. Leaves minutely pilose above.