Annuals or biennials, 20-150+ cm. Stems erect, stramineous, glabrous (branched distally). Cauline leaf blades oblong to obovate, 30-50(-80) mm, lengths mostly 2-4 times widths, bases ± clasping, margins dentate (teeth apiculate to setose), apices rounded, faces glabrous, obscurely, if at all, gland-dotted. Heads borne singly or in open to crowded, corymbiform arrays. Involucres broadly urceolate, 10-15 × 15-25 mm. Phyllaries in 3-5 series, spreading to appressed, subulate to linear-lanceolate, apices recurved to straight, attenuate, slightly to moderately resinous. Ray florets 25-45; laminae 10-15+ mm. Cypselae whitish to grayish, 2-4 mm, apices smooth or minutely coronate, faces smooth or striate; pappi (persistent or tardily falling) of 25-40 barbellate bristles 3-7+ mm subtending 8-15+ barbellate, setiform awns or subulate scales 7-10 mm (the longer surpassing disc corollas). 2n = 12.

Flowering Aug-Oct. Disturbed sites, prairies, railroads, roadsides; 100-1500 m; Ariz., Ark., Calif., Colo., Ill., Iowa, Kans., La., Mich., Mo., Nebr., N.Mex., Okla., Tex.

Glabrous annual or biennial 4-15 dm, commonly simple to near the top, leafy throughout, the lvs sessile, clasping, oblong to ovate or elliptic- obovate, rounded or obtuse at the tip, mostly 3-8 נ1-4 cm, spinose-dentate; heads few, large, the disk 1.5-3 cm wide; invol bracts slightly or moderately imbricate, the outer ones (at least) with long, loose or spreading green tip, at least the larger bracts generally well over 1 mm wide; rays ca 25-50, 1-2 cm; achenes glabrous, the central ones sterile; pappus rather scanty, eventually deciduous; 2n=12. Open or waste places; w. Mo. to La., Tex., and N.M., and intr. e. to Ill. Aug., Sept. (Prionopsis c.)

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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