Flora of North America species comparison

15–120 cm;

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

yellow-brown at base, 10–50 cm.

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.

sheaths glabrous;

blades glaucous, widest blades 6.1–12.3 mm wide, smooth abaxially.

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.

0.71–0.93 of culm height, rarely all spikes separate, peduncles of lateral spikes smooth, 0.4–11 cm;

peduncles of terminal spikes 1.5–37(–62) mm, usually overlapping or shorter than distal lateral spike;

proximal bract sheath loose, abaxially glabrous, sheath front slightly convex, elongated 0.2–2.2 mm beyond apex;

ligules (3–)5.2–10.2 mm;

distal bract slightly shorter than to much exceeding terminal spike.

(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.

(3–)4–6, usually distal 2–3 overlapping;

lateral spikes pistillate, longest ones with 11–25(–28) perigynia, 8–32 × 3.3–6.1(–6.8) mm, ratio of spike length (in mm) to flower number = (0.97–)1–1.3(–1.6);

terminal spikes 6–32 × 1.8–3.3 mm.

(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.

spirally imbricate, 42–56-veined, unwrinkled, narrowly ovoid, (3.7–)3.9–4.5(–4.7) × 1.5–2.2 mm, (1.9–)2.1–2.6(–2.8) times as long as wide, obtusely triangular in cross section, dull, base gradually tapered, apex gradually tapered;

beak absent or straight, 0–0.2(–0.4) mm.

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

obovoid, 2.6–3.1 × (1.3–)1.4–1.6 mm, 0.5–0.63 times as long as perigynia, loosely enveloped by perigynia;

stipe straight, 0.1–0.3(–0.5) mm;

beak bent (0–)30–90°, (0.1–)0.2–0.4(–0.5) mm.

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 1.9–3.2(–4.5) × 1.3–2.2 mm, margins pale ferrugineous to whitish, entire, apex with awn 0.1–0.9(–1.9) mm.

scales (3.9–)4.5–5.3 × 1.6–2 mm.

1.6–2.6 mm.

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