Flora of North America species comparison

15–120 cm;

vegetative culms few, inconspicuous, usually fewer than 15 leaves, not strikingly 3-ranked.

acutely angled, 10–90 cm, glabrous.

sheaths adaxially white-hyaline, summits U-shaped or sometimes prolonged to 2 mm beyond collar and rounded, smooth;

distal ligules 2.2–3.5 mm;

blades 3–5 per fertile culm, 12–30 cm × 1.5–3.5 mm.

basal sheaths red-brown;

sheath apex U-shaped;

blades hypostomic, glabrous, 3–6 mm wide.

open, brown, (1.3–)2.5–5(–6.5) cm × 5–18 mm;

proximal internode (3–)6–13(–23) mm; 2d internode 2–12 mm;

proximal bracts scalelike or bristlelike, shorter than inflorescences.

proximal bract shorter than inflorescence, 0.5–3 mm wide.

(3–)4–7, 5–7 on larger culms, distant, distinct, ovoid to ellipsoid, 7–17(–24) × 4–8(–12) mm, base attenuate or rarely rounded, apex acute to rounded;

terminal spike usually with conspicuous staminate base.

erect;

proximal 2–4 spikes pistillate, 1–2.5 cm × 3–5 mm, base cuneate;

terminal 1–2 spikes staminate.

(10–)15–40(–45) per spike, ascending-spreading, green or reddish brown, veinless or faintly and irregularly 1–5-veined adaxially, orbiculate or broadly ovate, plano-convex, (2.6–)3.4–4.8(–5.2) × (2–)2.3–3.2 mm, 0.5–0.6 mm thick, 1.2–1.8 times as long as wide, nearly leathery, margin flat, including wing 0.3–0.8 mm wide, ciliate-serrulate at least distally, smooth;

beak pale green or brown at tip, flat, ± ciliate-serrulate, abaxial suture with gold or reddish brown-hyaline margin, distance from beak tip to achene 1.5–2.4 mm.

ascending, pale brown with red-brown spots on apical 1/2, veinless, somewhat flattened, loosely enclosing achenes, ellipsoid or obovoid, 2–4 × 1.2–2.3 mm, dull, apex obtuse or acute, papillose;

beak red-brown, 0.2–0.3 mm.

orbiculate to broadly ovate, 1.5–2.2 × 1.3–1.8 mm, 0.5–0.6 mm thick.

not constricted, dull.

scales white-hyaline, tinged reddish brown, usually with whitish, pale gold, or green midstripe, broadly lanceolate to narrowly ovate, 2.6–4.3 mm, as long as to 0.7–0.9 mm shorter than perignyium beaks, narrower than perigynia, margins thin, sometimes involute, apex mostly acute.

scales purple-brown, equaling perigynia, apex obtuse or acute, awnless.

= 48, 52, 56, 60, 64, 68.