General:
Stout biennial or perennial herb from a taproot; stems ribbed, sparsely to moderately hairy, simple to branched, 0.3-2.0 m tall.

Leaves:
Basal leaves broadly lanceolate, up to 40 cm long, green to dark green above, glabrous or sparsely hairy above and below, irregularly lobed or coarsely toothed, usually more than 1/2 the width of the leaf blade, margins of the segments with 3-5 slender, yellow spines; stem leaves narrowly elliptic or oblong, 10-16 cm long, alternate, otherwise similar to the basal, uppermost reduced.

Flowers:
Heads solitary to many in small clusters at the ends of branches, nodding when young; involucres egg-shaped, 2-4 cm tall; involucral bracts linear-lanceolate, moderately to densely cobwebby, not much graduated, outer ones tapering to a prominent 1-2 mm spine, innermost unarmed; disk flowers purplish-pink, 12-24 mm long; styles exceeding the flowers by 3-8 mm.

Fruits:
Achenes prismatic, several-nerved, glabrous, purplish-black; pappus buff or whitish, feathery bristles.

Source:  The Illustrated Flora of British Columbia