4. Anemone richardsonii Hooker, Fl. Bor.-Amer. 1: 6. 1829.
Yellow anemone, anémone de Richardson
Anemone vahlii Hornemann
Aerial shoots 5-30 cm, from rhizomes, rhizomes horizontal. Basal leaves 1, simple; petiole (0.8-)2-8(-12) cm; leaf blade reniform to ±orbiculate, (1-)1.5-3(-4) × 1.5-4 cm, base somewhat cordate, margins crenate to serrate ±throughout, apex acute to broadly acute, surfaces glabrous or ±villous, or abaxially glabrescent; segments primarily 3, rhombic; lateral segments unlobed or 1×-lobed; ultimate lobes 4-10(-15) mm wide. Inflorescences 1-flowered; peduncle puberulous; involucral bracts 2-3, 1-tiered, simple, ±similar to basal leaves, primarily rhombic, 1-3.5 cm, bases distinct, cuneate, margins crenate on distal 1/2, apex acute to narrowly acute, surfaces glabrous or ±villous, or abaxially glabrescent; segments 3, primarily rhombic; lateral segments unlobed, 2-10 mm wide. Flowers: sepals (4-)6(-8), yellow (rarely abaxially yellow, tinged blue, and adaxially yellow), elliptic, 8-15 × 4-10 mm, abaxially villous, especially proximally, adaxially glabrous; stamens 25-55. Heads of achenes loosely spheric; pedicel 3-20 cm. Achenes: body ovoid to oblong, 3-4 × ca. 1.5 mm, not winged, glabrous; beak recurved, 4-6 mm, glabrous. 2 n =14.
Flowering spring-summer (May-Aug). Thickets, moist woods, meadows, slopes; 20-2200 m; Greenland; Alta., B.C., Man., Nfld., N.W.T., Que., Sask., Yukon; Alaska; Asia.