Stems erect, more or less branched at the summit, rough-pubescent, slender, 2 to 7 feet high from a perennial root. Leaves opposite, roughpubescent, closely sessile or rarely short petioled, blunt at the apex, rounded at the base, crenate toothed 1 to 4 inches long, one-half to 1 inch wide, the upper pairs smaller and distant. Heads white, about one-fourth of an inch high, each with about five tubular flowers, the heads arranged in a cymose panicle; involucre bell-shaped, composed of about three series of overlapping linear-lanceolate, pointed and densely pubescent bracts, the outer ones shorter.
In moist, usually sandy soil, mainly near the coast from Massachusetts to Florida, West Virginia and Louisiana. Flowering from July to September.
Memoir 15 N. Y. State Museum
A. Rough Or Vervain Thoroughwort - Eupatorium verbenaefolium