Perennials, 50-200 cm. Stems (from short caudices) multiple, branched distally, puberulent throughout. Leaves opposite (proximal) or alternate (nodes often appearing leafy because of development of leaves on lateral buds without axis elongation); sessile; blades (often ternately lobed) or lobes linear, 5-100 × 0.2-0.5(-1) mm, bases ± cuneate, margins entire (strongly revolute), apices rounded to acute, faces glabrate, gland-dotted. Heads in dense, paniculiform arrays. Phyllaries 8-10 in 2-3 series, oblong, 0.5-2.5 × 0.2-0.5 mm, apices acuminate and mucronate, abaxial faces glabrous or glabrate, not or little, if at all, gland-dotted. Florets 5; corollas 2-2.5 mm. Cypselae 1-1.7 mm; pappi of 20-30 bristles 2-2.5 mm. 2n = 20.
Coarse, the stems 5-20 dm, clustered on a thick, woody caudex, puberulent, or glabrate below, freely branched upward; lvs very numerous and narrow, delicate, glandular-punctate, glabrous, the lowest ones opposite, the others alternate, mostly 2-10 cm, often with axillary fascicles or with short, sterile, leafy axillary branches, the main ones pinnately divided into a few filiform segments mostly ca 0.5(-1.0) mm wide, those of the infl mostly simple; heads very numerous in an elongate true panicle; invol 2-3.5 mm, the inner bracts much longer than the outer, usually mucronate or abruptly acuminate; fls 3-6, white or chloroleucous; 2n=20. Open places, often in old fields and pastures; coastal states from N.J. to Fla., w. to Tex. and s. Ark., in our range wholly on the coastal plain. Sept., Oct.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
