Flora of North America species comparison

coarse, 1.8–3 mm thick, typically with long, unbranched segments from which shoots arise singly every few nodes.

sharply trigonous, (10–)25–80(–100) cm, scabrous-angled distally.

brown to chestnut at base, surrounded by remains of old leaf bases, but not conspicuously fibrillose; flowering culms 30–80 mm, usually longer than leaves at maturity, 1–2 mm thick, glabrous but finely scabrous within inflorescence.

basal sheaths dark brown to nearly black;

sheaths with hyaline inner band, apex not prolonged, glabrous;

ligules 0.6–2.6 mm;

blades 1–3(–3.5) mm wide.

sheaths glabrous, basal ones dark chestnut, grading to light brown and green on back, all bearing blades, sometimes very reduced in size on basal ones;

sheath fronts brown-hyaline or membranous, darker brown and often red dotted toward apex;

blades rigid, flat or channeled near base, 2.5–7 mm wide, glabrous but margins, edges of adaxial surface, and midrib of abaxial surface finely scabrous.

elongate, 0.9–4 cm;

spikes 5–18(–25), usually unisexual; staminate spikes lanceoloid; pistillate spikes ovoid.

peduncles of lateral spikes slender, to 100 mm (proximal spikes) or to 30 mm (distal spikes), minutely scabrous; of terminal spike 3–20 mm, glabrous;

proximal bracts much shorter than inflorescences;

sheaths 10–75 mm;

blades 1.5–3.5 mm wide.

brown to nearly black at maturity, essentially veinless, usually stipitate, ovate, plano-convex, (2.2–)2.6–3.7 × 1.2–1.9 mm, dull;

beak 0.7–1.2 mm, 1/4–1/2 length of body, apex ± hyaline, obscurely bidentate.

green to straw colored, sparsely red dotted, 2-ribbed and finely 7–10-veined, slightly inflated around achene, ovoid, 5–6.5 × 1.5–2.5 mm, membranous, base rounded, apex gradually tapering to beak, glabrous;

beak bidentate, 2.5 mm including teeth, teeth hyaline, narrow, to 1 mm.

substipitate, 2–2.5 × 1.2–1.7 mm.

scales straw colored to pale reddish brown, with hyaline margins, ovate, apex acute to acuminate-awned, dull to ± satiny.

scales pale hyaline tinged with light brown, with midrib green to golden green, ovate to elliptic, nearly as long as mature perigynia, gradually narrowing to acuminate or short-cuspidate apex, glabrous except scabrous midrib.

(1.8–)2.2–3.9 mm, apiculus bristly hairy (30X).

spikes 4–12, 1–3 per node;

proximal spikes well separated, arching, pistillate with 20–50 perigynia attached 1 mm apart, cylindric, 15–45 × 6–9 mm;

distal spikes androgynous or staminate, usually crowded near apex.

spike staminate, sometimes compound at base, 20–60 × 2.5–4 mm; the set of predominantly staminate spikes usually conspicuously raised above predominantly pistillate ones.