Flora of North America species comparison

often ascending or spreading, 4-angled or sometimes terete, sometimes sulcate, 1–7 cm × 0.2–0.3 mm, soft to firm.

terete, when dry with to 12 blunt ribs, 20–55 cm × 0.5–1.1 mm, soft to firm, internally mostly hollow with complete transverse septa 2–4 mm apart, evident only on sectioning culm.

sheaths stramineous, distal sheaths often splitting abaxially, slightly inflated distally, oblique, apex acute.

distal leaf sheaths persistent, not splitting, proximally dark red, distally stramineous or reddish, thinly papery, apex often red to brown, obtuse to subtruncate, slightly callose, tooth present, 0.5–1(–3.7) mm.

ovoid, 1.5–4 × 0.8–2 mm, apex acute;

floral scales 4–15, 8 per mm of rachilla, colorless or reddish brown, midrib region green, ovate-lanceolate, not folded lengthwise, 1–1.5 × 0.5–0.7 mm, mibrib obscure to somewhat keeled, apex narrowly acute to acuminate, slightly recurved.

lanceoloid, 5–13 × 2–2.5 mm, apex acute to obtuse;

proximal scale amplexicaulous, entire;

subproximal scale empty;

floral scales appressed in fruit, 10–100, 10–12 per mm of rachilla, medium brown to stramineous, midrib regions often greenish, ovate, 1–1.5 × 1 mm, entire, apex rounded to subacute, carinate in distal part of spikelet.

perianth bristles absent;

anthers 0.3–0.5 mm.

perianth bristles 5–6, pale brown, stout, equaling achene;

stamens 3;

anthers brown, 0.4–0.9 mm;

styles 3-fid or a few 2-fid in the same spikelet.

with angles and longitudinal ridges ca. 6–10, rather prominent, broadly ovoid, less than 2 times longer then wide, (0.55–)0.65–0.75 × 0.3–0.4 mm, apex blunt, trabeculae distinct, 20–30.

falling with scales, green or medium or dark brown, obpyriform, compressed-trigonous or some biconvex in same spikelet, angles prominent, 0.6–0.8 × 0.5–0.6 mm, neck short or absent, smooth or very finely reticulate at 20–30X.

grayish, mostly appressed, pyramidal, often depressed, 0.1–0.2 × 0.1–0.25 mm.

brown, depressed-pyramidal, 0.1–0.2 × 0.2–0.3 mm.