Thalictrum alpinum L.

Stems erect, scapose, or nearly scapose with very slender rhizomes, (3-)5-20(-30) cm, glabrous. Leaves all basal or single cauline leaf near base, 2-10 cm. Leaf blade 2×-pinnately compound, proximal primary divisions ternate; leaflets cuneate-obovate to orbiculate, apically 3-5-lobed, 2-10 mm, surfaces glabrous. Inflorescences racemes, usually elongate, few flowered. Flowers: pedicels recurved in fruit; sepals early deciduous, purplish tinged, ovate or elliptic, 1-2.3(-2.7) mm; stamens 8-15; filaments purple; anthers bright yellow, 1.5-3 mm; stigmas purple. Achenes 2-6, nearly sessile; body lance-obovoid, 2-3.5 mm, with thick veins. 2 n = 14, 21.

Plants 5--40 cm tall, glabrous. Roots fibrous. Rhizome slender. Stems simple or rarely branched, erect. Leaves 4 or more, all basal; petiole 1.5--3 cm; leaf blade pinnately 2-ternate, 1.5--4 cm; leaflets cuneate-obovate to orbicular-ovate, 3--5 × 3--5(--20) mm, thinly leathery, apex 3(--5)-lobed; lobes crenate. Inflorescence racemelike, few flowered; peduncle simple or branched. Pedicel erect or recurved at anthesis, recurved in fruit. Sepals early deciduous, purplish tinged, ovate to elliptic, ca. 2 mm. Stamens 7--10(--15); filament purplish, filiform; anther yellow, 1.2--3 mm, apex mucronate. Carpels (2--)3--5(--6); stigma purple, narrowly triangular, equaling ovary. Achenes shortly stipitate or sessile; body narrowly ovoid to lanceolate-obovoid, 2--3.5 mm; persistent style broadly triangular; veins ca. 8, stout. Fl. Jun--Aug.

Greenland; B.C., Nfld., N.W.T., Que., Yukon; Alaska, Calif., Colo., Idaho, Mont., Nev., N.Mex., Oreg., Utah, Wyo.; n Eurasia.

Gansu, Hebei, Ningxia, Qinghai, Shaanxi, Shanxi, Sichuan, Xinjiang, Xizang, Yunnan [Afghanistan, Bhutan, India, Kazakhstan, Mongolia, N Myanmar, Nepal, Pakistan, Russia (Siberia), Sikkim, Vietnam; Europe, North America].

Flowering late spring-summer (Jun-Aug).

Wet meadows, damp rocky ledges and slopes, and cold (often calcareous) bogs in willow-sedge, lodgepole pine, and spruce-fir; 0-3800m.

Damp valleys, slopes, meadows, bogs; 2400--5300 m.

Thalictrum alpinum var. hebetum B. Boivin