Annuals or perennials, 20-200 cm; fibrous-rooted. Stems stipitate- to sessile-glan-dular (commonly with eglandular but viscid hairs as well), not arachnose. Leaves petiolate or sessile; blades (succulent, drying thin) lance-ovate to ovate or ovate-elliptic, mostly 4-15 × 1-7 cm, margins shallowly serrate, faces glabrate to moderately or densely pubescent (hairs crinkly). Heads in corymbiform arrays (flat-topped to rounded, often layered, sometimes incorporating relatively long, leafy, lateral branches, clusters of heads terminal on branches, some lateral branches nearly equaling or surpassing central portions). Involucres cylindro-campanulate, 5-6 × 4-8(-10) mm. Phyllaries usually cream, sometimes purplish, minutely sessile-glandular (outer usually also puberulent), sometimes glabrate. Corollas pink to rosy or purple. Pappi persistent, bristles distinct. 2. = 20.
Annual, ±fibrous-rooted, to 10(-15) dm, glandular-puberulent to occasionally subglabrate; lvs ample, lanceolate to elliptic or ovate, 4-15 נ1-7 cm, acute or acuminate, ±serrate, short-petiolate, or sometimes, especially the upper, merely tapering to the base; heads pink-purple, numerous in a generally ±flat-topped or layered infl; invol evidently pubescent with short, multicellular, glandular-viscid hairs, the bracts imbricate in several series, commonly ±pink or purple, at least distally; 2n=20. Salt or brackish (seldom freshwater) marshes, chiefly along the coast; Mass. to Fla., Tex., and trop. Amer., and occasionally inland, as in s. Ill. and se. Mich. Aug., Sept. Most of our plants are var. succulenta (Fernald) Cronquist, seldom over 6 dm, with large heads, the invol 5.5-7 mm high, the disk 5-9 mm wide. In Md. and Va. this passes into the more southern var. odorata, taller, with smaller heads, the invol 4-5.5 mm high and the disk 4-7 mm wide. (P. purpurascens)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
