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.

 

Russia Flora: Shrub up to 7 (10) m tall. Terminal buds with one pair of outer scales, short-stalked, fusiform, 5-6 mm long, usually dark red, glabrous. Shoots dark cherry-colored, glabrous when mature. Leaves 5-(7)-lobed, 4-8 cm long, 5-9 cm wide, with cordate base, thin, glabrous above, more or less densely brown-hairy along veins below; leaf lobes with short sharp tips, doubly finely serrate, central lobe slightly larger than lateral ones. Petioles 3-6 cm long, shorter than leaf blade, thin, red-brown, glabrous when mature. Inflorescence a simple raceme with 7-14 flowers. Flowers about 8 mm in diameter, yellow, glabrous; petals and sepals elliptical, about 3.5 mm long; stamens 8, almost half as long as perianth segments. Samaras about 2.5 cm long, diverging at obtuse or acute angle; their wings not narrowing towards ends. (Table XIX).

Distribution: South Kuril (Iturup Island). (Fig. 65). - In low and middle mountain forests. Ornamental shrub. Honey plant.

General distribution: Japanese-Chinese (Japan - islands of Hokkaido and Honshu). - Described from Japan.

Note: Despite the obvious similarity between A. tschonoskii and A. komarovii, we maintain the view of them as independent species with different life forms and ecological preferences. On Honshu Island, where both species grow, A. tschonoskii occurs at altitudes of 500-700 m above sea level, while A. komarovii occupies the southern part of the island and low mountains of the central part.