Flora of North America species comparison

fertile ones upright or nearly so;

nodes without axillary bulblets.

fertile ones upright or nearly so;

nodes without axillary bulblets.

5–10 per culm;

sheaths of proximal leaves green or whitish;

proximal sheaths and blades with septa many, conspicuous or not;

blades 20–55 cm × 8–16 mm.

4–11 per culm;

sheaths of proximal leaves red;

proximal sheaths and blades with septa few to many, conspicuous or inconspicuous;

blades 23–60(–75) cm × 5–15(–20) mm.

terminal, rarely also with 1 lateral inflorescence from distal leaf axil;

rays ascending or divergent (commonly both in same inflorescence), smooth throughout or scabrous at distal end, rays without axillary bulblets;

bases of involucral bracts green or margins brown, not glutinous.

terminal;

rays divaricate or ascending, proximal branches almost smooth, distal branches scabrous, rays without axillary bulblets;

bases of involucral bracts green, black, or red, not glutinous.

aggregated in a few dense clusters of 12–130 (largest cluster with 40–50+), spikelets sessile, narrowly ovoid, 4–5 × 1.8–2.3 mm;

scales black or brownish black with pale midribs, elliptic to ovate, 1.6–2.8 mm, ending in terete or flat awn 0.4–0.6(–1.2) mm.

in dense clusters of (1–)3–18 (largest cluster with 6 or more spikelets), spikelets sessile, 2–8 × 1–3.5 mm, ovoid or narrowly ovoid;

scales green or black, broadly ovate or ovate to broadly elliptic or elliptic, 1.1–3.4 mm, apex rounded to acute or apiculate or occasionally mucronate, apiculus or mucro (if present) to 0.2 mm.

perianth bristles persistent, 6, rather stout, straight or curved, longest bristles equaling achene, with retrorse, thin-walled, round-tipped teeth in distal 0.3–0.5, enclosed within scales;

styles 3-fid.

perianth bristles persistent, (3–)4(–6) per flower, stout, straight or curved, shorter than to 1.5 times as long as achene, with retrorse, thick-walled, sharp-pointed teeth densely arranged almost to base, enclosed within (occasionally weakly projecting from) scales;

styles 2(–3)-fid.

pale brown or almost white, oblong-elliptic to elliptic or obovate in outline, plumply trigonous or plano-convex, 0.8–1.2 × 0.4–0.6 mm.

almost white, ovate to obovate in outline, biconvex to plano-convex, 0.7–1.6 × 0.8–1 mm.

= 56.

= 64, 66.