Ohwi 1985 Flora of Japan

Small tree or shrub with glabrous branches; leaves nearly orbicular, 5-8 cm. long and as wide, palmately 5-lobed, beyond the middle, cordate at the base, with rusty-brown curled puberulence on nerves beneath while young, the lobes rhombic- ovate to ovate, caudately long-acuminate, incised and doubly serrate, the petioles 3-5 cm. long, glabrous; inflorescence a rather dense, more than 10-flowered raceme, 4-7 cm. long, on short peduncles, brownish pubescent on the nodes, the pedicels 4-7 mm. long, spreading to ascending; flowers small, about 4 mm. across, pale green; sepals oblong, about 1 mm. long; petals oblong, about 2 mm. long; stamens 8, as long as the petals; samaras glabrous, nearly horizontally spreading, 1.5-2 cm. long.

Mountains; Honshu, Shikoku, Kyushu.