Carex tribuloides Wahlenb.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Species Description - Tufted, aphyllopodic, usually stout, 5–10 dm; main lvs 3–7 mm wide, surpassed by the stems; sheaths ventrally green-veined almost to the summit; spikes 5–15, gynaecandrous, 6–12 mm, ovoid to subglobose or obovoid, usually blunt, rounded to acute at base, sessile, densely to loosely aggregated into an ovoid or oblong cluster 2–5 cm; pistillate scales lanceolate, half to two-thirds as long as the perigynia, merely acute, pale brown with hyaline margins and tip; perigynia numerous (more than 30), appressed-ascending, green or becoming stramineous, 4–5(–5.5) × 1–1.3(–1.6) mm, 3–4 times as long as wide, lanceolate, flat or barely distended over the achene, the wing rather abruptly narrowed about the middle and often obsolete in the lower fourth, obscurely nerved on both sides, gradually tapering into the beak; achene lenticular, 1.5 × 0.5–0.75 mm. Wet woods and meadows; Que. and Me. to Minn., and Neb., s. to Fla., La., and Okla., more common s.