UW Burke Herbarium species comparison

Basal leaves lyrate and pinnatifid, up to 20 cm. long and 5 cm. wide;

cauline leaves smaller, becoming linear and entire upward.

Lower leaves oblanceolate, petiolate, often coarsely few-lobed; middle and upper leaves smaller, becoming sessile, mostly toothed to entire.

Heads several, broader toward the base;

involucre 10-15 mm. high, its middle and outer bracts spine-tipped, the larger spines 11-22 mm. long;

flowers yellow;

pappus of the outer flowers wanting, that of the others 3-5 mm. long;

receptacle densely bristly.

Heads terminating the numerous branches;

involucre 11-18 mm. high, higher than broad; the middle and outer involucre bracts usually with comb-like, blackish appendages 1-3 mm. long;

flowers all tubular, the marginal flowers enlarged;

pappus none.

Achene.