Toothed Whitetop Aster

Collections of Sericocarpus asteroides purportedly from Indiana and Wisconsin are of questionable provenance or chance introductions.

Plants 14–65 cm. Stems erect, puberulent. Leaves: basal persistent at flowering, winged-petiolate, blades oblanceolate to obovate or spatulate, 20–150 mm, serrate near apices, puberulent; cauline sessile, blades narrowly to broadly ovate, 10–110 × 4–30 mm, bases cuneate, margins serrate, distal becoming entire, apices acuminate to acute, faces puberulent. Heads 2–5 per branch, in corymbiform arrays. Involucres 4–7 mm at flowering. Peduncle bracts absent. Phyllaries in 3–4 series, outer 2–4 mm, mid 3–5 mm, glabrate. Ray florets 3–7; corolla tubes 2–4 mm, laminae 2–6 mm. Disc florets 9–20; corolla tubes 3–4 mm, lobes 0.6–2 mm. Ovaries fusiform-obconic, 0.8–2 mm, densely strigose; pappi: inner series 4–5 mm. 2n = 18.

Conyza asteroides Linnaeus, Sp. Pl. 2: 861. 1753; Aster asteroides (Linnaeus) MacMillan; A. paternus Cronquist