Flora of North America species comparison

10–15 mm diam.

bluntly trigonous with nearly flat sides throughout to cylindric proximally, obscurely trigonous distally, 1–4 m × 4–10 mm, smooth.

often arching to decumbent, cylindric, ridged when dry, 0.09–0.65 m × 0.5–1.5 mm.

3–4, basal, ca. 1/6 culm length;

sheath fronts coarsely pinnate-fibrillose;

blades 0–1, dorsiventrally flat, not more than 1/2 sheath length, distal blade to 20 × 2 mm.

3–4, 1(–2) cauline;

sheath fronts not pinnate-fibrillose;

blades 1–2, proximally thickly C-shaped in cross section, distally flat, rudimentary to longer than sheath, 1–200 × 0.2–1 mm, smooth or margins distally spinulose.

3 or more times branched, branches to 21 cm;

proximal bract usually erect, obtusely trigonous to subcylindric-channeled, 1–8 cm, margins often scabridulous.

capitate or of 1 spikelet or with 1 or 2 branches to 15 mm;

proximal bract erect, like leaf blades, 5–15 cm.

25–150+, solitary and in clusters of 2 or more, 5–11 × 3 mm;

scales orange-brown, brightly lineolate-spotted, broadly oval, 2.5 × 2 mm, margins ciliolate, flanks veinless, apex rounded, notch 0.1–0.2 mm deep, awn not contorted, usually bent outward, 0.3 mm, sparsely scabrous.

achenes blackish brown, nearly equilaterally sharply trigonous, ovoid to obovoid, 1.3–1.8 × 1–1.4 mm, with 10–20 mostly sharp ridges;

beak 0.1 mm.

perianth members 2–4, dark red-brown, thickly strap-shaped or trigonous, equaling achenes, fringed with brownish, soft, blunt hairs;

anthers 1.5 mm;

styles 2-fid.

perianth absent;

anthers 0.3–0.5 mm;

styles 3-fid.

dark gray-brown when ripe, unequally biconvex or plano-convex, ovoid to obovoid, 1.8–2.2 × 1.3 mm;

beak 0.2 mm.

achenes trigonous, 2.2–3 mm including stout, tapered beak 0.3 mm, with many obscure to evident horizontal ridges.

= 68.

= 50.