Korea Flora: Trees up to 14m. Bark light grayish brown. Winter buds lanceolate, acuminate, densely yellow pubescent scales 2, terminal buds larger than lateral buds (6-10mm long). Branchlets yellowish or redish, hiary. Leaf scars V form. Leaves opposite and deciduous, suborbicular, base cordate, 5(7)-lobed, 8-14cm × 8- 13cm, margin coarsely serrate, middle lobes not serrate apically, adaxially glabrescent, abaxially densely yellowish tomentose along the vein,
petiole 3-12cm, slightly pubescent and reddish, Inflorescence terminal, erect, racemose-paniculate, pubescent, andromonoecious; peduncles 3-5 cm, Pedicel 4-6 mm, pubescent. Sepals 4, outside pubescent. Petals 5, yellow. Stamens 8, or 7-10, glabrous, longer than petals, Ovary densely pubescent. wing including nutlet 15mm, puberulent;

2n= 26.
Flowering late May – late June
Fruting mid Sept- mid Oct
Distribution Northeastern China, far Eastern Russia and southern Kurils, Japan (Hokkaido, Honshu); Korea [North, Central (Baekdudaegan)]

Japan Flora: Tree, the branches yellowish puberulent; leaves orbicular and 5-angled, 8-13 cm. long, 8-15 cm. wide, cordate at base, often whitish and with dull yellowish pubescence beneath, palmately 5(-7)-lobed on outer third, the lobes ovate-triangular, acuminate, sharply serrate and incised, the petioles 6-12 cm. long; inflorescence an erect raceme, 10-15 cm. long inclusive of the peduncles 3-5 cm. long, densely many-flowered, with pale brown soft hairs, the pedicels about 10 mm. long; flowers yellowish; sepals broadly lanceolate, about 1 mm. long; petals narrowly obi a nee- olate, about 2 mm. long; samaras loosely short-pubescent or glabrous, ascending, 1.5-2 cm. long. July-Aug. Highmountains; Hokkaido, Honshu (centr. distr. and northw.), Shikoku. Sakhalin, Korea, Manchuria, e. Siberia, and Ku­riles.

f. pilosum Nakai. Usuge-ogarabana. Leaves less prominently pubescent beneath. Occurs with the spe­cies

 

China Flora: Deciduous tree, up to 10(-15) meters tall. Young branches purple, yellow pubescent, old branches brown, nearly glabrous. Winter buds short conical, dark purple, yellow pubescent. Leaves nearly round, 10-12 cm long, 7-9 cm wide, 5(7) deeply lobed, cordate at base, lobes broadly ovate, pointed at apex, coarsely serrulate and doubly serrate, glabrous above, densely yellowish hairs below, densely hairy above veins, 5 basal veins; petiole 5-10 cm long. Raceme terminal, up to 10 cm long, erect, pubescent. Dioecious; sepals yellowish green, lanceolate, 2 mm long, slightly pubescent; petals white, slightly yellowish, oblanceolate, 3 mm long; stamens glabrous; disk slightly lobed; located outside the stamens, ovary densely pubescent. The samaras are light red when young and yellow-brown when ripe. The nutlets are slightly hairy, with a core diameter of 6 mm and a wing length of 1.5-2 cm, with the two wings at right angles. The flowering period is May and the fruiting period is September.

It is produced in Heilongjiang, Jilin and Liaoning, and grows in sparse forests at an altitude of 500-1500 meters. It is distributed in eastern Siberia, Russia, North Korea and Japan. [translated from Higher Plants of China]