Stems cespitose, erect, slender, 2-8 dm; lvs terete, septate, 1-3 mm thick; infl rarely congested, usually narrowly ovoid or pyramidal, 5-12 cm, less than half as wide, with (3-)5-20(-50) hemispheric or broadly obpyramidal heads 6-10 mm thick, each with (5-)10-50 eprophyllate fls; tep green or stramineous, lance-subulate, subequal, 2.6-3.9 mm, at least the sep broadly scarious-margined, in the lower half; stamens 3(6), shorter than the tep; fr stramineous or light brown, unilocular, about equaling the tep, trigonously ovoid-prismatic, 2.8-4 mm, acute or rarely obtuse, mucronate; 2n=40. Wet soil, meadows, shores, and low woods; Me. and N.S. to Wis., s. to Fla. and Mex.; B.C. to Oreg.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.