Perennials, 30-80(-100) cm. Stems erect, villous-puberulent. Leaves opposite; petioles 1-8(-12) mm; blades narrowly to broadly deltate to nearly ovate or lanceolate, 2-7(-9) × 1.5-4 cm, (usually subcoriaceous) bases rounded or truncate to barely cuneate or subcordate, margins usually crenate, sometimes crenate-serrate to dentate or subentire, apices acute to obtuse, faces minutely pilose. Heads clustered. Peduncles 2-9 mm, densely and closely puberulent. Involucres 3.5-5 mm. Phyllaries: apices acute, abaxial faces puberulent to villous-puberulent. Corollas white, lobes sparsely villous. Cypselae usually glabrous or sparsely puberulent (near apices), rarely hirtellous on angles. 2n = 34.

Flowering late Aug-Oct(-Nov). Sandy soils, burned pinelands, turkey oak sand ridges, pine-oak and oak-hickory upland woods, old fields, roadsides, fencerows, moist sites; 100-900 m; Ala., Conn., Del., Fla., Ky., La., Md., Mass., Miss., N.J., N.Y., N.C., Ohio, Pa., R.I., S.C., Tenn., Va., W.Va.

Intergrades (probable hybrids) between Ageratina aromatica and A. altissima were identified by A. F. Clewell and J. W. Wooten (1971) over a broad area of their sympatry. They also found intergrades between A. aromatica and A. jucunda where their ranges meet.

Resembling no. 9 [Eupatorium rugosum Houttuyn.], and not always sharply distinct, avg smaller, seldom over 8 dm, and with shorter, firmer, more generally distributed pubescence; lvs relatively thick and firm, obtuse or acute, crenate or crenate-serrate, 3-7(-10) נ2-5 cm, more than 4 times as long as the short petiole; invol bracts obtuse or rounded to acute; fls mostly 10-19 per head, the cor-lobes commonly villous externally, at least near the tip; 2n=34. Dry woods, especially in sandy soil; Mass. to Fla., w. to s. O., Ky., Tenn., and e. La. Aug.-Oct.

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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