Japan Flora: Glabrous to sparingly pubescent coarse perennial herb with rather stout branching rhizomes; stems 30-80 cm. long, with a few deciduous scales at base, terete, few-leaved; leaves few, 2- or 3-ternate, the leaflets thinly chartaceous, often lustrous, narrowly ovate to ovate-orbicular, 3-10 cm. long, 1-6 cm. wide, acuminate to caudate, incised and toothed, sometimes pinnately lobed; inflorescence 10-30 cm. long, short-pubescent; flowers many, white, short-pedicel led; petals broadly spathulate, small; fruit pendulous on a deflexed pedicel, the carpels lustrous, about 2.5 mm. long, the styles short, about 0.5 mm. long. June-Aug.
Hokkaido, Honshu, Shikoku, Kyushu; rather common and variable. Kamchatka, Kuriles, Sakhalin, Ussuri, Manchuria, Korea, and China.
var. insularis H.Hara. Petals larger, elliptic, about 1.2-1.5 mm. long, firm; calyx-lobes larger; style longer, about 0.8 mm. long. Izu Isis. (Oshima).
var. laciniatus (Hara) H.Hara. Leaflets deeply incised, ovate-lanceolate; petals in staminate flowers narrowly oblong, 2 mm. long. Hokkaido (s. Hidaka Prov.).
var. astilboides (Maxim.) H.Hara. Pedicels and follicles erect when mature. High mountains; Honshu (Mount Hayachine in Rikuchu Prov.).
var. subrotundus (Tatew.) Hara. Leaflets rather firm, ovate-orbicular to broadly ovate, rounded with a short cusp at apex, acutely toothed; fruit pendulous on a deflexed pedicel. Hokkaido (Mount Apoi in Hidaka Prov.)