Perennials, 40-150 cm; taprooted. Stems 1-6, erect or ascending, much branched, basally setose, distally glabrous . Leaves basal and cauline; petiolate (basal and proximal cauline, petioles winged); blades (at least basal) oblanceolate, pinnatifid (often runcinate) or coarsely and irregularly toothed (apices acute; distal cauline reduced, entire). Heads (terminal and axillary) usually borne singly (sometimes clustered along stems and branches). Peduncles (nearly 0) not inflated, not bracteate. Calyculi of 3-4, minute bractlets. Involucres cylindric, 2.5-5 mm diam. Phyllaries 5-9 in ± 1 series, linear-lanceolate, equal. Receptacles pitted, glabrous, epaleate. Florets 7-15; corollas (soon withering) yellow. Cypselae tan to black, nearly cylindric, beaks slender or stout, ribs 5+ (with alternating grooves), faces glabrous; pappi persistent (on expanded discs at tips of beaks), of 40-50+, distinct, white, smooth bristles in 1 series. x = 5.
Fls all ligulate and perfect, yellow, 7-15 per head; invol cylindric, calyculate; achenes multinerved, glabrous, muricate above, and with a beak that is expanded at the top into a pappiferous disk; pappus of numerous capillary bristles, generally white; lactiferous, branching, often rush-like herbs with well-developed, usually pinnatifid basal lvs and reduced, mostly scattered and entire cauline lvs. 25, temp. Eurasia.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
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