Stem to 1 m, hirsute, especially below; basal lvs long- petioled, the terminal segment rotund to reniform, 5-12 cm wide, often 3-lobed, the lateral few, much smaller, interspersed with several to many minute lfls; upper lvs short-petioled to sessile, deeply 3-lobed or 3-foliolate; pet yellow, 4-7 mm, somewhat exceeding the sep; achenes minutely pubescent throughout, hirsute about the summit; basal segment of the style minutely glandular, the terminal segment minutely pubescent; 2n=42. Moist woods and rocky ledges, sometimes weedy; Nf. and Lab. to Alas. and e. Asia, s. to Me., Vt., N.Y., Mich., Minn., and Calif. May-July. Var. perincisum (Rydb.) Raup, occurring from n. Mich. w. and n., has relatively strongly dissected lvs, the terminal lfl of the middle cauline ones 3-cleft nearly to the base with the lobes again cleft or laciniate. (G. oregonense) The widespread var. macrophyllum has less dissected lvs, the terminal lfl of the middle cauline ones 3-cleft to about the middle with the lobes merely toothed.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.