Erigeron philadelphicus
Sp. Pl. 2: 863. 1753.
Annuals, biennials, or short-lived perennials, 4–80 cm; fibrous-rooted, caudices simple. Stems erect (green proximally, leafy to arrays), hirsuto-villous to villous proximally, loosely strigose to sparsely hirsute distally, minutely glandular. Leaves basal (persistent or withering by flowering) and cauline; basal blades oblanceolate to obovate, (15–)30–110(–150) × 10–25(–40) mm, margins shallowly crenate to coarsely serrate or pinnately lobed, faces sparsely hirsute to villous, eglandular; cauline blades oblong-oblanceolate to lanceolate, gradually reduced distally (bases clasping to auriculate-clasping). Heads (1–)3–35 usually in corymbiform arrays (ultimate branches arising near stem tips). Involucres 4–6 × 6–15 mm. Phyllaries in 2–3 series (sometimes basally connate), hirsuto-villous to sparsely hirsute or glabrous, sometimes minutely glandular. Ray florets 150–250(–400); corollas usually white, sometimes pinkish, 5–10 mm, laminae not coiling or tardily coiling. Disc corollas 2.1–3.2 mm. Cypselae 0.6–1.1 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae, inner of 15–20(–30) bristles.
Distribution
Alta., B.C., Man., N.B., N.S., N.W.T., Nfld. and Labr. (Nfld.), Ont., P.E.I., Que., Sask., Yukon, Ala., Ark., Calif., Colo., Conn., D.C., Del., Fla., Ga., Idaho, Ill., Ind., Iowa, Kans., Ky., La., Maine, Mass., Md., Mich., Minn., Miss., Mo., Mont., N.C., N.Dak., N.H., N.J., N.Mex., N.Y., Nebr., Nev., Ohio, Okla., Oreg., Pa., R.I., S.C., S.Dak., Tenn., Tex., Va., Vt., W.Va., Wash., Wis., Wyo., introduced worldwide in temperate areas as a weed.
Discussion
Varieties 3 (3 in the flora).
Selected References
None.
Lower Taxa
Key
| 1 | Cauline leaf faces sparsely hirsute to villous | Erigeron philadelphicus var. philadelphicus |
| 1 | Cauline leaf faces glabrous or glabrate | > 2 |
| 2 | Leaves of basal rosettes withering by flowering; salt marshes, British Columbia | Erigeron philadelphicus var. glaber |
| 2 | Leaves of basal rosettes persistent through flowering; crevices in shale or dolomite, usually beside rivers or lakes, Ontario, Quebec, New York, and Vermont | Erigeron philadelphicus var. provancheri |