Narrowleaf Whitetop Aster

Plants 22–75 cm. Stems erect (stout, branched), glabrate. Leaves: basal and proximalmost cauline withering by flowering; cauline sessile; blades linear, 10–80 × 1–10 mm, margins entire, apices acuminate, faces glabrate. Heads 2–4 per branch, in broadly corymbiform arrays. Peduncle bracts broadly lanceolate to narrowly ovate, glabrate. Involucres 4–6 mm. Phyllaries in 3–4 series, outer 2–4 mm, mid 3–4 mm, glabrate. Ray florets 2–6; tubes 2–4 mm, laminae 4–11 mm. Disc florets 5–15; corollas 2–4 mm, lobes 1–2 mm. Ovaries obconic, 0.8–1.3 mm, densely strigose; pappi: inner series 3–6 mm. 2n = 18.

Conyza linifolia Linnaeus, Sp. Pl. 2: 861. 1753, not Aster linifolius Linnaeus; A. solidagineus Michaux; Sericocarpus solidagineus (Michaux) Nees