Stems decumbent or creeping, rooting nodally, hispid to strigose or almost glabrous, base not bulbous. Roots never tuberous. Basal leaf blades ovate to reniform in outline, 3-foliolate, 1-8.5 × 1.5-10 cm, leaflets lobed, parted, or parted and again lobed, ultimate segments obovate to elliptic or sometimes narrowly oblong, margins toothed, apex obtuse to acuminate. Flowers: receptacle hispid or rarely glabrous; sepals spreading or reflexed from base, 4-7(-10) × 1.5-3(-4) mm, hispid or sometimes glabrous; petals 5(-150), yellow, 6-18 × 5-12 mm. Heads of achenes globose or ovoid, 5-10 × 5-8 mm; achenes 2.6-3.2 × 2-2.8 mm, glabrous, margin forming narrow rib 0.1-0.2 mm wide; beak persistent, lanceolate to lance-filiform, curved, 0.8-1.2 mm. 2 n = 14, 32. Flowering late winter-summer (Mar-Aug). Meadows, borders of marshes, lawns, roadsides; 0-2500 m; introduced; Greenland; St. Pierre and Miquelon; Alta., B.C., N.B., Nfld., N.S., Ont., P.E.I., Que., Yukon; Ala., Alaska, Ark., Calif., Conn., Del., D.C., Idaho, Ill., Ind., Iowa, Ky., Maine, Md., Mass., Mich., Minn., Mo., Mont., Nebr., Nev., N.H., N.J., N.Y., N.C., Ohio, Oreg., Pa., R.I., S.C., S.Dak., Tenn., Tex., Utah, Vt., Va., Wash., W.Va., Wis., Wyo.; Central America; South America; native to Eurasia; Pacific Islands; Australia. Ranunculus repens is widely naturalized in many parts of the world. Plants with sparse pubescence have been called R . repens var. glabratus . Horticultural forms with the outer stamens transformed into numerous extra petals occasionally become established and have been called R . repens var. pleniflorus . These variants have no taxonomic significance.
Hirsute to strigose or subglabrous perennial, mostly creeping, rarely ascending or erect; lvs petioled, 3-parted, the terminal segment stalked, all segments broadly obovate to subrotund, cleft or lobed, sharply toothed; pet 8-15 mm, two-thirds as wide; anthers 1-2 mm; achenes broadly and obliquely ovate, 2.5-3.5 mm, sharply but narrowly margined, the beak triangular, usually curved, 0.8-1.5 mm; 2n mostly =32. Native of Europe, naturalized in fields, lawns, roadsides, and wet meadows. May-July. Robust, subglabrate plants have been called var. glabratus DC., and double- flowered ones have been called var. degeneratus Schur or var. pleniflorus Fernald.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.