Stems clustered, slender, erect, 2-5 dm, with usually 2-4 terete, septate lvs; infl decompound, very diffusely branched, widely spreading, 1-2 dm, usually constituting a third of the height of the plant, bearing very many obpyramidal, 3-10-fld heads; fls eprophyllate; tep subequal, linear-subulate, 2.3-2.8 mm; stamens 3; fr unilocular, golden-brown, prismatically linear-trigonous or subtriquetrous, 4-6 mm, a fifth as thick, gradually attenuate, very acute, much surpassing the tep. Wet soil and muddy shores; s. Ind. to Mo. and Okla., s. to Ala. and Tex.; coastal plain from se. Va. to S.C.; reported from W.Va.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.