Heads 30-50(-100); bracts linear-oblanceolate to narrowly oblanceolate or linear-subulate, 25-70 × 2-7 mm. Involucres 4-5 × 6-14 mm. Phyllaries sometimes reflexed, spatulate to obovate-spatulate, subequal, membranous margins broad, (2-)2.5-6 mm wide, apices cuspidate; outer 2.6-3.8 × 0.5-1.6 mm; inner 3.2-4 × 0.9-1.5 mm. Cypselae obovoid to obcordiform, winged; pappus awns 0.7-2 mm, lengths ² / 3 + cypselae. 2n = 18. Flowering Aug-Sep. Marshes, streams, sloughs, wet ditches; 10-400 m; Ark., Conn., Iowa, Kans., Maine, Md., Mass., Minn., Miss., Mo., Nebr., N.Dak., Ohio, Okla., R.I., S.Dak., Vt., Va., Wis. Variety latisquama is considered endangered in Maryland.