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.

4–8 per culm;

sheaths of proximal leaves green or brownish;

proximal sheaths and blades with septa few, inconspicuous;

blades 13–26 cm × 3–7 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, rarely also with 1 lateral inflorescence from distal leaf axil;

rays ascending to divaricate, smooth or weakly scaberulous near nodes, rays without axillary bulblets;

bases of involucral bracts green or speckled with red or black-margined, 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 2–20 (largest cluster with 10 or more), spikelets sessile, ovoid or narrowly ovoid, 2.5–6 × 1–3 mm;

scales black with pale midribs, elliptic to ovate, 1.5–2.7 mm, apex mucronate to short-awned, mucro or awn 0.2–0.4 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, 6, slender, contorted, much longer than achene and projecting beyond it, with scattered, often inconspicuous, antrorse teeth in distal 1/2, enclosed within scales or some bristles projecting;

styles 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.

pale to medium brown, obovate or elliptic in outline, plumply trigonous or plano-convex, 0.9–1.3 × 0.6–0.8 mm.

= 56.