Densely tufted, the stiff, smooth stems 2–7 dm, usually surpassing the slender, involute lvs; spike usually solitary, 0.8–2.5(–4) cm, gynaecandrous or unisexual; lateral spikes 1 or 2 and much smaller, or usually none; lower 2 scales empty and erect; anthers 2–3.5 mm; pistillate scales ovate, about equaling the body of the perigynium, usually acute, reddish-brown with hyaline margins; perigynia to ca 25, at least the lower ones spreading or reflexed, castaneous, planoconvex, ovate, 2.6–4.7 mm, spongy-thickened at base, with to 15 faint nerves dorsally and to 7 ventrally, the serrulate-margined beak a fifth to two-thirds as long as the body; achene lenticular; 2n=ca 62. Sphagnum-bogs and other open, wet, low places; Lab. and Nf. to Del. and Md., w. to Ont., n. Mich., and n. Minn.; disjunct in N.C. and Miss.