Stems roughish-puberulent, rather bushy, 1 to 2 feet high, from a perennial root, bearing opposite, linear leaves and densely corymbosely branched above. Numerous smaller leaves fascicled in the axils of the stem or on short, axillary branches; leaf blades entire, blunt at the apex, narrowed at the base, one-half to 2 inches long, one-twelfth to one-sixth of an inch wide, firm and usually with more or less revolute margins. Heads white, arranged in a flat-topped panicle, each head about one-third of an inch high with about five tubular flowers, surrounded by a campanulate involucre, composed of linear-oblong, puberulent bracts imbricated in about three series, the outer ones shorter.
In dry fields, Massachusetts to Florida and Texas. Flowering in August and September.
Memoir 15 N. Y. State Museum
B. Hyssop-Leaved Thoroughwort - Eupatorium hyssopifolium