Plants 6-12(-20+) dm. Stems puberulent. Leaves mostly cauline; blades elliptic to lance-ovate or lanceolate, 6-16(-20+) cm × 18-48+ mm, l/w = 2.5-4(-6+), abaxially usually puberulent to tomentose or pannose (hairs ± erect, ± curled), seldom glabrate, resin-gland-dotted, adaxially scabrellous, glabrescent, not resin-gland-dotted. Heads in corymbiform-scorpioid arrays. Peduncles 3-35 mm. Involucres broadly campanulate to urceolate, (6-)7-10+ × 5-9+ mm. Phyllaries 50-70+ in 6-7 series, sparsely scabrellous, glabrescent (seldom resin-gland-dotted), margins ciliolate, the outer lanceolate, 1-2 mm, inner linear-oblong to oblong, 6-7(-9+) mm, tips acute or rounded-apiculate. Florets 30-55+. Cypselae 3.5-4; pappi stramineous to whitish, outer scales 25-30, 0.5-1.1 mm, contrasting with 35-40+, 6-8+ mm inner bristles. 2n = 34.
Stem stout, 1-2 m, pubescent or thinly tomentose; lvs lanceolate, 6-20 נ1.5-6 cm, coarsely serrate to subentire, scabrellate above, thinly to densely tomentose beneath, at least along the veins, with long, crooked hairs; infl widely branched, flattened or concave; fls 32-58; invol bracts appressed, purple, or greenish along the inconspicuous midvein, rounded to acute, often apiculate, arachnoid-ciliate, glabrous or puberulent on the back; pappus tawny to brown; 2n=34. Moist prairies, bottomland pastures, and low roadsides; sw. Ont. to Io. and Nebr., s. to Ala. and Tex. Our plants mostly contaminated by introgression from no. 5 [Vernonia gigantea (Walter) Trel.]
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Infrequent to frequent, usually in dry places and rarely in wet places. It is generally found along roadsides and railroads, in pasture fields, and less frequently in open woods.