Japan Flora: Somewhat scandent shrub, 1-2 m. high; branches much elongate, with prominent retrorse prickles, short-pubes­cent while young; leaves 20-40 cm. long, prickly on rachis and petioles, the pinnae 6-16, the leaflets vivid green on upper side, whitish beneath, sometimes slightly pubescent, the lateral nerves not prominent; racemes terminal, 20-30 cm. long, pedunculate, the bracts narrowly ovate, caducous, 3-4 mm. long, densely brownish pubescent, the pedicels spreading, slender; flowers 25-30 mm. across, expanded, yellow; stamens red, densely villous on the lower half; legumes oblong, slightly arcuate, sessile, flat, glabrous, about 10 cm. long, 3 cm. wide, with a thick winglike outer suture.  Apr.-June. Woods and grassy places in lowlands and hills.

Honshu (Kanto Distr. and westw.), Shikoku, Kynshu; rather common. Ryukyus and China (?).