This is widespread in woodland of eastern North America, except on the southeastern Coastal Plain. In Ky. Aquilegia occurs mostly on rocky slopes below limestone cliffs. But it is also scattered below sandstone cliffs, where soils are locally base-rich due to accumulation of dust and reducing leaching (Walck et al. 1999; and dissertation of S.W. Francis cited therein). In addition to association with rocks, the species can become locally frequent along trails (Hall & Kuss 1989). The spectacular red flowers with yellowish centers appear in late Apr and early May, when hummingbirds arrive in the transition from spring to summer; see also Bignonia capreolata, which has similarly colored flowers, produced at the same tiime (Bertin 1982). However, bees are probably more frequent pollinators (Macior 1966), and the species can often self-pollinate despite considerable inbreeding-depression (Herlihy & Eckert 2007). Variation within this species is probably significant but has not been studied in detail (Munz 1946; F, W). From northeast to southwest, there may be general decrease in robustness of plants and more deeply cleft leaflets. Plants from the Ordovician Palisades of Kentucky Rv. tend to be relatively robust (up to 10 dm or more), with less ddeeply cleft leaflets, and flower mostly in early to late May. Plants from Mississippian limestone of the Knobs region tend to be less robust (no more than 5 dm tall), with more deeply cleft leaflets, and flower mostly during mid-April to early May.