Plants 50-180 cm; stolons and rhizomes absent, fallen stems frequently rooting at nodes. Stems erect. Leaf blades linear to oblanceolate, obovate, or oblique-elliptic; cauline 45-120 × 8-12 mm, bases not decurrent. Heads in corymbiform arrays, branches spreading to ascending, most bracts leaflike, 10-40 × 3-8 mm. Peduncles 6-35 mm; bracts (0-)1-3, linear to linear-oblanceolate, 1-2.5 mm. Involucres 2-2.5(-4) × 4-6 mm. Phyllaries in 2-4 series, linear to subulate, subequal, 0-4 merging down peduncle; outer 1.3-2 × 0.3-0.6 mm; inner 1.5-3 × 0.3-0.6. Ray florets 20-35; corollas white to lilac, laminae 5-9 mm, tubes 0.6-0.9 mm. Disc florets 80-134; corollas 2.1-2.9 mm. Cypselae obovoid, 1.3-2.1 × 0.8-1.3 mm, wings 0.2-0.3 mm wide; pappi awns 0.3-0.8 mm. 2n = 18. Flowering late Sep-Dec. Moist, gray sand, in semishade or deep shade, hardwood floodplain forests; 0-10 m; Fla., La., Miss.