Flora of North America species comparison

20–90 cm;

vegetative culms inconspicuous with few leaves clustered at apex.

pale brown to ivory at base, sometimes with a few brown fibrillose remains of previous year’s leaves, but not densely covered with fibrils; flowering stems 25–110(–200) cm, longer than leaves at maturity, 1–1.3 mm thick, glabrous.

sheaths white-hyaline or green-veined, sometimes papillose, summits U-shaped, not distally expanded;

distal ligules 2.2–6 mm;

blades 3–4 per fertile culm, 11–25 cm × 1.7–4.2 mm.

sheaths glabrous, proximal ones ivory grading distally to light green, all bearing blades, pale hyaline on front;

blades flat, (3–)5.5–8.5(–15) mm wide, glabrous on both surfaces, finely scabrous on margins.

mostly dense, brown, 1.1–3 cm × 5–14 mm;

proximal internode 1–4 mm; 2d internode 1.4–3.4 mm;

proximal bracts scalelike, with bristle tips shorter than inflorescences.

peduncles of lateral spikes 5–20 mm, scabrous;

peduncle of terminal spike less than 20 mm, scabrous;

proximal bracts usually shorter than entire inflorescence;

sheaths 20–100 mm;

blades 2–3 mm wide.

3–10, usually overlapping, ovoid to globose, 4–10 × 3–7 mm, base rounded or truncate, apex rounded.

ascending to ascending-spreading, light to dark reddish brown, conspicuously 3+-veined abaxially, faintly or basally 1–3-veined adaxially, winged to base, ovate or elliptic, plano-convex, 2.5–3.8 × (1–)1.2–2 mm, 0.35–0.45 mm thick, 1.9–2.5 times as long as wide, margin flat, including wing 0.2–0.5 mm wide, 1b ciliate-serrulate at least distally;

beak reddish brown at tip, flat, ± ciliate-serrulate, abaxial suture with reddish brown-hyaline margin, distance from beak tip to achene 1.2–2.2 mm.

green maturing to light brown, conspicuously 2-ribbed but otherwise veinless except for short inconpicuous veins at base, substipitate, tightly enveloping achene, obovoid, 4.5–6 × 1.4–1.8 mm, membranous, apex abruptly narrowed to tubular beak, glabrous;

beak bidentate, slender, 2–3 mm, teeth 1 mm.

ovate or elliptic, 1–1.3 × 0.6–0.9 mm, 0.3–0.4 mm thick.

sessile, 2.2–2.6 × 1.2–1.5 mm.

scales reddish brown, usually with green or whitish to brown midstripe, lanceolate, 2.5–3.5 mm, shorter and narrower than perigynia, apex acuminate or acute.

scales white-hyaline with broad green midrib, oblong-lanceolate, shorter than mature perigynia, apex acute, cuspidate, or awned, glabrous.

spikes: 3–5, 1 per node, the proximal well separated, erect to somewhat nodding, distal ones crowded near apex;

proximal spikes pistillate with 15–40 spreading perigynia attached 1–1.5 mm apart, cylindric to elongate, 15–60 × 3–5 mm;

distal spikes staminate or androgynous.

spike staminate or androgynous with a few pistillate flowers at base, 15–40 × 2.5–3 mm.

= 68, 70.

= 58 (Czechoslovakia, Germany, Great Britain, Iberian Peninsula, Poland, Sweden)