Plants colonial fron long-creeping rhizomes. Culms (10-)20-90 cm × 0.5-0.8(-1.5) mm, scabrous distally. Leaves: blades trigonous-channeled in cross section, to 45 cm × 1-1.5(-3) mm; distal leaf blade 3-25 cm × 1-1.5 mm, longer than its (1-)2.5-9 cm sheath. Inflorescences: blade-bearing involucral bracts solitary, similar to distal leaf, blade sometimes brown proximally, 0.8-6 cm. Spikelets (1-)2-7, in subumbels, ovoid, 7-10 mm in flower, 20-30 mm in fruit; peduncles 5-20(-60) mm, scabrous; scales green to red-brown to almost black, sometimes with green center, ovate-elliptic, 3-4.5 mm, scarious, margins narrow, to 0.2 mm, midrib prominent, fading distally or proximal scale with 2-4 thinner or equally prominent lateral ribs, apex obtuse. Flowers: perianth bristles 10 or more, cream, 10-20 mm, smooth; anthers 1-2 mm. Achenes narrowly obovoid, 2.5-3 mm. Fruiting summer. Bogs and wet, peaty substrates; 0-500 m; St. Pierre and Miquelon; N.B., Nfld. and Labr., N.S., Ont., P.E.I., Que.; Conn., Maine, Mass., Mich., N.H., N.J., N.Y., Pa., R.I., Vt.
Colonial from slender rhizomes; stems arising singly, slender, erect, 3-8 dm, obtusely trigonous, scaberulous above; blades 1-2 mm wide, channeled, the uppermost to 15 cm, equaling or longer than its sheath; bract erect, usually shorter than the umbel; spikelets 3-6, short-pedicellate in a head-like infl, or 1 or 2 on scabrous pedicels to 5 cm; scales stramineous to reddish-brown, ovate, obtuse or rounded; bristles sordid white; achene brown, narrowly obovate-oblong, 2.5-3 mm. Bogs and swamps, often under conifers; Nf. to Minn., s. to N.J., Pa., and Ill. Fr June-Sept.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
