Vernonia glauca (L.) Willd.
Family: Asteraceae
Broad-Leaf Ironweed
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Plants 6-10+ dm. Stems sparsely appressed-puberulent, glabrescent. Leaves mostly cauline; blades lanceolate to oblanceolate, 10-15(-18+) cm × 30-45(-70+) mm, l/w = 2.5-3.5(-4), abaxially scabrellous (hairs awl-shaped), resin-gland-dotted or not, adaxially glabrous or sparsely puberulent. Heads in corymbiform to paniculiform arrays. Peduncles 2-35 mm. Involucres ± hemispheric, 5-8 × 7-8 mm. Phyllaries 40-60 in 5-6 series, sparsely puberulent to tomentulose, glabrescent, margins ciliolate, the outer lance-deltate to subulate, 1-3 mm, inner oblong, 4-7+ mm, tips acuminate to subulate or filiform. Florets 30-45+. Cypselae 3-4 mm; pappi stramineous to whitish, outer subulate scales or bristles 30, 0.5-1.5+ mm, intergrading with 30+, 6-8 mm inner subulate scales or bristles. 2n = 34.

Flowering Jul-Sep. Dry fields, marshes; 10-400 m; Ala., Del., D.C., Ga., Md., Mass., N.J., N.C., Pa., S.C., Va.

Stems 0.7-1.5 m, puberulent above, otherwise glabrous or nearly so; lvs lance-ovate to ovate, 1-2.5 dm נ2-10 cm, shortly acuminate, saliently serrate, glabrous or barely scabrellate above, distinctly paler and puberulent beneath, rather abruptly narrowed to a petiole-like base; infl loose, very irregular, some branches commonly elongate; fls 32-48; invol 5-9 mm, its principal bracts arachnoid-ciliate, lanceolate to ovate at the appressed base, narrowed to a filiform tip 2-5 mm; pappus bright-stramineous or pale tawny to nearly white; 2n=34. Upland woods; se. Pa., s. N.J., Md., and e. W.Va., s. to Va., Ga. and Ala., avoiding the coastal plain southward. Mostly July.

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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