Ohwi 1985 Flora of Japan

Shrub or small tree with glabrous branches; leaves 5-angled, nearly orbicular, 5-9 cm. long, 5-10 cm. wide, cordate to nearly rounded at base, while young rusty-brown pubescent beneath, on nerves near base, and on petioles, soon glabrous, palmately 5-lobed on outer half, the lobes rhomboid to rhombic-ovate, long-acuminate, often with a short lobe on each side near base, incised and doubly serrate, the petiole glabrous, 2-5 cm. long, reddish; inflorescence loosely few-flowered, short-pedunculate, 2-5 cm. long, slightly rusty-brown pubescent on the nodes, the pedicels ascending, 8-15 mm. long; flowers 8-10 mm. across, pale yellow; sepals and petals nearly alike, spreading, linear- oblanceolate, about 4 mm. long; stamens about 8, as long as the petals; samaras glabrous, ascending to obliquely spreading, 2.5-3 cm. long. June-July. Coniferous forests to the lower alpine regions;

Hokkaido, Honshu (centr. distr. and northw.). s. Kuriles.