Aerial shoots (15-)20-80 cm, from caudices on rhizomes, caudices ascending, rhizomes ascending to horizontal. Basal leaves 1-5, simple, deeply divided; petiole 8-22(-37) cm; leaf blade orbiculate, 4-10 × 5-15(-20) cm, base sagittate to nearly truncate, margins serrate and incised on distal 1/3-1/2, apex acuminate, surfaces puberulous (more so abaxially); segments primarily 3, lanceolate to oblanceolate; lateral segments again 1×-lobed or -parted (proximal lobe occasionally lobed again); ultimate segments 10-30(-35) mm wide. Inflorescences 1(-3+)-flowered, rarely cymes; peduncle puberulous to villous, distally densely villous; involucral bracts 3 (secondary involucres with 2), remotely subtending flowers, (1-)2-tiered, simple, ±similar to basal leaves, broadly obtriangular, 3-cleft, 3-10 cm, bases broadly cuneate, connate, margins sharply, irregularly serrate and incised on distal 1/3-1/2, apex acuminate, surfaces puberulous, more so abaxially; segments 3, lanceolate to oblanceolate; lateral segments unlobed or 1×-lobed; ultimate lobes (8-)10-15(-20) mm wide. Flowers: sepals (4-)5(-6), white, obovate, (8-)10-20(-25) × 5-15 mm, hairy or glabrous; stamens 80-100. Heads of achenes spheric to ovoid; pedicel 7.5-11.5 cm. Achenes: body obovoid to ellipsoid, (2.5-)3-6 × 3.5-6 mm, winged, strigose or glabrate; beak straight, 2-6 mm, strigose, not plumose. 2 n =14. Flowering spring-summer (May-Aug). Damp thickets, meadows, wet prairies, lake shores, streamsides, clearings, occasionally swampy areas; 200-2800 m; Alta., B.C., Man., N.B., Nfld., N.W.T., N.S., Ont., P.E.I., Que., Sask.; Colo., Conn., Ill., Ind., Iowa, Kans., Maine, Md., Mass., Mich., Minn., Mo., Mont., Nebr., N.H., N.J., N.Mex., N.Y., N.Dak., Ohio, Pa., S.Dak., Vt., W.Va., Wis., Wyo. Various parts of Anemone canadensis were used medicinally by Native Americans in the treatment of wounds, nasal hemorrhages, eye problems, and sore throats, to counteract witch medicines, and as a general panacea (D. E. Moerman 1986).
From Flora of Indiana (1940) by Charles C. Deam
Found in low ground in woodland and along roadsides, mostly in alluvial soil along streams. Infrequent to frequent in the northern half of the state and in the Wabash Valley, becoming rare or absent in the hilly counties.
Rhizomatous perennial, 2-8 dm; basal lvs long-petioled, rotund, deeply 3-parted, the segments more or less cleft and sharply toothed; involucral lvs similar but sessile; peduncles 1-3, the lateral ones commonly with a small secondary involucre; sep 5, white, mostly 12-20 mm long; achenes flat, suborbicular, 3-5 mm, strigose; style 2-5 mm, strigose; 2n=14. Sandy shores, damp prairies, and wet meadows, abundant; e. Que. to Alta., s. to Md., W.Va., Ky., Mo., and N.M. May-Aug.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.