Flowering from May to June; fruiting from July to September.
Actaea asiatica is close relative of Actaea erythrocarpa, but differs from the latter in its pedicels thickened at fruiting (vs. not thickened), ca. 1 mm in diameter (vs. 0.6 mm), fruits black (vs. red, sometimes white).
Actaea asiatica is occurring in Gansu, Hebei, Heilongjiang, Hubei, Jilin, Liaoning, S Nei Mongol, Qinghai, Shaanxi, Shanxi, Sichuan, E Xizang, Yunnan of China, Japan, Korea, Russia (Far East).
Rhizome black-brown, with numerous slender fibrous roots. Stems 30-80 cm tall, terete, 4-8 mm in diameter, unbranched, basally glabrous, apically white pubescent. Leaves 2 or 3, proximal cauline leaves 3 times ternately pinnate, long petiolate; petiole 10-15 cm long; leaf blade triangular, up to 25 cm wide, abaxially glabrescent, adaxially subglabrous; terminal leaflet ovate to broadly ovate-rhombic, 4-10 cm long, 2-6 cm wide, 3-fid, margin sharply serrate; lateral leaflets ovate to obliquely ovate. Distal cauline leaves similar to proximal ones, but smaller. Inflorescence racemose, 2.5-5 cm, to 17 cm at fruiting; rachis and pedicels densely white or gray pubescent; bracts linear-lanceolate, ca. 2 mm. Pedicels 5-8 mm. Sepals obovate, 2.5-3 mm. Petals spatulate, 2-2.5 mm. Filaments 3-5 mm; anthers ca. 0.7 mm. Pedicels at fruiting 1-1.5 cm, ca. 1 mm in diameter. Fruit solitary, purple-black, ca. 6 mm in diameter. Seeds ca. 6, dark brown, ovate, ca. 3 mm long, 2 mm wide.
The chromosomal number of Actaea asiatica is 2n = 16 (Nishikawa, 1981; Wang et al., 1994; Yang, 1998).
Growing in forest; 500-3000 m.
