Herbs, perennial, 30-80 cm tall, with short rhizomes; stems erect, branched in upper part, usually with sterile branches at leaf axils above middle, sparsely or densely pilose. Basal stem leaves withered by anthesis. Middle stem leaves sessile; leaf blade linear-lanceolate, 6-10 × 0.7-1.7 cm, pectinately pinnatilobed or pinnatipartite, abaxially densely villous, adaxially sparsely villous; lobes linear or linear-lanceolate, basally amplexicaul, margin unequally serrulate, apex acute; upper stem leaves similar, progressively smaller. Synflorescence a dense terminal flat-topped panicle. Capitula many. Involucres broadly oblong or subglobose, (4-)5-7 mm in diam.; phyllaries in 3 rows, broadly lanceolate to elliptic, 2-4 × 1.2-2 mm, abaxially sparsely villous, scarious margin brown, midvein convex. Paleae similar to phyllaries. Ray florets 6-8; lamina white, broadly elliptic, apex 3-denticulate. Disk florets white, 5-lobed. Achenes broadly oblanceolate, ca. 2 × 1.1 mm, with white lateral ribs, sometimes 1- or 2-ribbed abaxially. Corona absent. Fl. and fr. Jul-Sep. 2n = 36.
Perennials, 50–80 cm (fibrous-rooted and rhizomatous). Stems 1, erect, branched or unbranched distally, sparsely villous to glabrate. Leaves sessile; blades linear-lanceolate to oblong-lanceolate, 5–10 cm × 4–8 mm, (margins serrate to doubly serrate, teeth antrorse) faces sparingly villous or glabrate. Heads 10–25+, in crowded, simple or compound, corymbiform arrays. Phyllaries 20–30 in ± 3 series, (light green, margins light to dark brown, midribs dark green or yellow-green) lanceolate to oblanceolate, faces (abaxial) sparingly tomentose. Receptacles convex; paleae oblong, 3.5–4.5 mm (apices dark, rounded). Ray florets 6–8(–12), pistillate, fertile; corollas white, laminae 1–3 × 2–3 mm. Disc florets 25–30+; corollas grayish or yellowish white, 2–3 mm. Cypselae 2.5 mm. 2n = 36.