Roundleaf ragwort

Senecio obovatus Muhlenberg ex Willdenow, Sp. Pl. 3: 1999. 1803; S. aureus Linnaeus var. obovatus (Muhlenberg ex Willdenow) Torrey & A. Gray; S. elliottii Torrey & A. Gray; S. elongatus Pursh; S. rotundus (Britton) Small

Perennials, 20–50+ cm; stoloniferous and rhizomatous (rhizomes horizontal to suberect). Stems 1 or multiple, loosely clustered, usually glabrous, sometimes tomentose proximally and in leaf axils. Basal leaves (and proximal cauline) petiolate; blades orbiculate, ovate, or obovate, 40–100+ × 20–80+ mm, bases tapering, rounded, or abruptly contracted, margins crenate, dentate, or serrate. Cauline leaves gradually reduced (sessile, clasping; pinnatisect or sublyrate). Heads 6–15+ in open or congested, corymbiform arrays. Peduncles bracteate, glabrous or proximally tomentose. Calyculi conspicuous. Phyllaries 13 or 21, green (tips sometimes reddish), 3–6 mm, glabrous or floccose-tomentose proximally. Ray florets 8–13(–21); corolla laminae 7–10 mm. Disc florets 40–50+; corolla tubes 2–3 mm, limbs 2–3 mm. Cypselae 1–1.5 mm, glabrous or hirsute on ribs; pappi 3–6 mm. 2n = 44, 88, 90.

Flowering late Feb–Apr (south), early Apr–early Jun (north). Meadows in deciduous woodlands, wet ditches, stream banks, rocky hillsides; 0–2500 m; Ont., Que.; Ala., Ark., Conn., Fla., Ga., Ill., Ind., Kans., Ky., La., Md., Mass., Mich., Miss., Mo., N.H., N.J., N.Mex., N.Y., N.C., Ohio, Okla., Pa., R.I., S.C., Tenn., Tex., Vt., Va., W.Va.; Mexico (Coahuila).

Packera obovata forms relatively large, stoloniferous colonies in wet sites.