Stems 15-90 cm. Basal leaves 2×-ternately compound, 7-30 cm, much shorter than stems; leaflets green adaxially, 17-52 mm, not viscid; primary petiolules 17-93 mm (leaflets not crowded), glabrous or pilose, sometimes somewhat viscid. Flowers pendent; sepals divergent from floral axis, red or apex green, lance-ovate to oblong-ovate, 8-18 × 3-8 mm, apex broadly acute to acuminate; petals: spurs red, straight, ± parallel to divergent, 13-25 mm, stout (at least proximally), abruptly narrowed near middle, blades pale yellow or yellow-green, oblong to rounded, 5-9 × 4-8 mm; stamens 15-23 mm. Follicles 15-31 mm; beak 10-18 mm. 2 n = 14. Flowering spring-summer (Mar-Jun). Shaded or open woods, often around cliffs, rock outcrops, and forest edges; 0-1600 m; Man., Ont., Que., Sask.; Ala., Ark., Conn., Del., Fla., Ga., Ill., Ind., Iowa, Kans., Ky., Maine, Md., Mass., Mich., Minn., Mo., Nebr., N.H., N.J., N.Y., N.C., N.Dak., Ohio, Okla., Pa., R.I., S.C., S.Dak., Tenn., Tex., Vt., Va., W.Va., Wis. P. A. Munz divided this species into five varieties, based on size of the plants, sepals, and leaflets and whether the leaves are 2-3×-ternately compound. The variation in size of these organs is not discontinuous or even bimodal, however, and I have not seen any material with 3×-ternately compound leaves. For this reason, no varieties are recognized here. The name Aquilegia canadensis var. hybrida Hooker has been misapplied to this species; the type specimen actually belongs to A . brevistyla (B. Boivin 1953). Aquilegia canadensis has also been reported from New Brunswick, but the specimen has been destroyed and the species has never been recollected in the province.
Native Americans prepare infusions from various parts of plants of Aquilegia canadensis to treat heart trouble, kidney problems, headaches, bladder problems, and fever, and as a wash for poison ivy; pulverized seeds were used as love charms; and a compound was used to detect bewitchment (D. E. Moerman 1986).
From Flora of Indiana (1940) by Charles C. Deam
Local throughout the state on the wooded bluffs of streams, wooded slopes and banks of streams, banks and slopes of deep ravines, and rarely far removed from stream courses. I have twice found it in open tamarack bogs where it was associated with Rhus vernix and Rhamnus alnifolia. I have also frequently found it growing in the rocky crevices of cliffs along streams. I suspected this wide difference of habitat would show some difference in the structure of the plants but I find none. The plant when taken from the wild and planted in the garden thrives and reproduces freely from seed, which fact is not entirely consistent with its restricted distribution along streams.
Stems 3-20 dm; basal lvs large, long-petiolate, cauline reduced upwards; lfls broadly obovate to subrotund, crenately toothed or lobed; fls nodding, 3-4 cm; sep red; pet with yellow blade and nearly straight red spur, the spur 1.5-2.5 cm; fls rarely wholly yellow or salmon-colored; stamens projecting in a column; 2n=14. Dry woods, rocky cliffs and ledges, and even peat bogs; N.S. to Sask., s. to Fla. and Tex. Apr.-June. (A. coccinea; A. latiuscula)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.