Erect perennial herb 0.6-1 m tall, rhizomatous or stoloniferous at the base, occasionally branching from the base; stems usually solitary, sparsely ascending-pubescent. Leaves sessile, narrowly ovate to narrowly elliptic, 7.5-16 cm long, 0.8-2.6 cm wide, base cuneate, margins serrate or obscurely serrate, apex acute or minutely obtuse, sparsely finely ascending-pubescent especially on the veins, somewhat glabrescent. Capitula in upper axillary lax corymbose scorpioid cymes; stalks of individual capitula absent or up to 13 mm long; involucres hemispherical-turbinate, 2-2.5 mm long; phyllaries 2-3-seriate, sometimes purplish at the apex, elliptic-oblong, 1.5-2 mm long, rounded, ciliate, with scarious margins. Florets 18-25 per capitulum; corolla pale lilac to purple, 3-5 mm long, limb urceolate, lobes 1 mm long. Achenes obconical, 2 mm long, 4-5-ribbed, truncate, with short apical rim. Fig. 28/5 (floret).
