Flora of North America species comparison

to 2 times wider than thick, 35–60(–70) cm × 0.5–1.3 mm, hard, usually with to 10 blunt ribs, at 20X often finely ridged and minutely granular.

terete or cross section elliptic (or rectangular), usually with to 8 blunt ridges when dry, 10–50 cm × 0.2–0.7(–1) mm, soft to firm, spongy.

distal leaf sheaths brown to reddish.

distal leaf sheaths persistent, not splitting, mostly proximally dark red, distally red to brown or green, thinly papery to thickly membranous, apex usually redbrown, subtruncate to obtuse or subacute, callose, tooth often present on most or all culms, to 1 mm.

3–12 × 3–4 mm;

proximal scale amplexicaulous, 3.5–4 mm, midrib region very broad and fleshy, apex entire;

subproximal scale with a flower;

floral scales 30–40, 8–10 per mm of rachilla, orange-brown to stramineous, midrib region stramineous, broadly ovate, papery or sometimes membranous, 3–4 × 2 mm, apex entire, rounded.

narrowly lanceoloid (to narrowly cylindric), 3–20 × 1.5–2.5 mm, apex acute;

proximal scale amplexicaulous, entire;

subproximal scale empty or with flower;

floral scales appressed or spreading in fruit, 15–40, 3–4 per mm of rachilla, orange brown, midrib regions often greenish, ovate, 2–3 × 1 mm, apex entire, rounded to obtuse in proximal part of spikelet, acute in distal part, carinate, at least in distal part of spikelet.

perianth bristles present, sometimes rudimentary, brown, length variable, obscurely retrorsely spinulose;

anthers brown, 1.7–2.2 mm.

perianth bristles 3–7, rarely apparently absent, stramineous to whitish, slender to stout, often unequal, rudimentary to slightly exceeding tubercle;

stamens 3;

anthers yellow to stramineous, 1.1–2 mm;

styles 3-fid, 0.3–0.4 × 0.2–0.3 mm.

subdeltoid in outline, sometimes broadly obpyriform, equilaterally trigonous, angles prominent, 0.9–1.2 × 0.7–1.1 mm, apex truncate.

falling with scales, yellow-brown or dark brown, ellipsoid or obovoid to obpyriform, compressed-trigonous, angles evident to obscure, rarely prominent, 0.8–1.4 × 0.5–0.7 mm, neck absent to long, smooth or sometimes minutely cancellate at 20–30X.

sessile, depressed-pyramidal, often apiculate, as wide as achene, 0.3–0.5 × 0.7–1.1 mm.

whitish, pyramidal, often higher than wide, 0.3–0.4 × 0.25–0.35 mm.

= 10.