Glabrous perennial 2-7 dm, the stems often zigzag, arising singly from slender creeping rhizomes; lvs few, fleshy, linear or nearly so, 4-15 cm נ1-5(-12) mm, the lower soon deciduous, the upper reduced and often bract-like; heads (solitary) several or many in an open infl, the peduncles subulate-bracteate; invol 6-9 mm, its bracts ±imbricate, firm, chartaceous, sometimes greenish upward but scarcely herbaceous, acuminate to sharply acute, the inner often purple- margined; rays mostly 15-25, blue to pink (whitish), 4-7 mm, sometimes circinately outrolled; 2n=10, 20. Salt-marshes along the coast; Mass. to Fla. and La.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.