Flora of North America species comparison

brown at base, densely covered with brown fibrillose remains of previous year’s leaves; flowering stems 30–90 cm, longer than leaves at maturity, 0.5–0.7 mm thick, glabrous but finely scabrous within inflorescence.

straight, (40–)65–110(–125) cm, tallest culms 65–125 cm.

sheaths glabrous, basal ones tinged with brown and all bearing blades, green to hyaline on back, white-hyaline on front;

blades flat, 2.5–4 mm wide, finely scabrous on adaxial surface and margins, glabrous on abaxial surface.

of flowering stems shorter than culms, to 28 cm × 1.8–3.8 mm;

ligules on distal cauline leaves truncate or rounded.

peduncles of lateral spikes slender, 20–60 mm, equaling or somewhat longer than spikes, finely scabrous;

peduncle of terminal spike 5–15 mm, scabrous;

proximal bracts equaling inflorescences or more often shorter;

sheaths 3–5 mm or rarely longer;

blades 1–1.5 mm wide.

peduncles of terminal staminate spikes (3–)10–60(–102) mm, 0.7–2.5 length of staminate spikes;

bracts 5–25 cm × 1.2–2.5 mm, 0.5–1.3(–1.9) times as long as inflorescences;

inner band of sheaths usually concave or truncate (occasionally convex).

proximal pistillate spikes 1–2(–3), distant, sessile or short-pedunculate, globose to ellipsoid or short-cylindric, 7–27 × 8–11 mm;

terminal staminate spikes pedunculate, (9–)17–39 × 1.4–2.5 mm.

shiny tan to golden green, 2-ribbed, but otherwise veinless, closely enveloping achene at maturity, ovoid-ellipsoid, 4.5–6.5 × 1.5–2 mm, membranous, base acute, apex abruptly contracted to beak, glabrous;

beak bidentate, narrowly tubular, nearly as long as body, finely scabrous on edge, teeth hyaline, 1 mm.

reflexed, yellow to yellowish green, (3.5–)3.9–5.2(–5.8) × 1.4–2.2 mm, apex abruptly narrowed;

beak forming angle greater than 20° with body, 1.4–2.2 mm, sparsely scabrous or, occasionally, smooth.

substipitate, 2–2.5 × 1.7–1.8 mm.

1.4–1.9 × 1.2–1.5 mm.

spikes 4–5, 1 per node;

proximal spikes well separated, nodding or drooping at maturity, pistillate with 10–40 perigynia about 1 mm apart, cylindric, 10–35 × 8–10 mm;

distal spikes crowded near apex, sessile or nearly so, staminate or androgynous, linear, less than 20 mm.

spike staminate or rarely with a few perigynia at base, 10–20 × 1.5–2 mm.

scales pale hyaline tinged with chestnut, narrow midrib green, sometimes finely scabrous, ovate-oblong, shorter than mature perigynia, apex long-acuminate, glabrous.

pistillate scales pale yellowish green, inconspicuous among perigynia, 2.1–3.3 × 0.9–1.3 mm; staminate scales reddish brown to pale brown, narrowly obovate to narrowly oblong, 2.9–5.6 × 1.2–1.9 mm, margins wide, pale hyaline, apex obtuse to acute.

2.1–3.6 mm.

= 42.