Flora of North America species comparison

erect, not spirally twisted, not contracted near spikelet, when dry usually with several blunt to acute ridges and sulcate, subterete to slightly compressed, to 2 times wider than thick, 5–35 cm × 0.2–0.5(–1.2) mm, soft to hard;

culm tufts often proximally bulbous (if bulbous then tunicated by papery-fibrous scales).

terete, 2–15 cm × 0.15–0.3 mm, firm to soft.

distal leaf sheaths stramineous to brown or reddish proximally, green to stramineous or brown distally, membranous to papery, apex often reddish, subtruncate to acute.

distal leaf sheaths persistent, not splitting, proximally stramineous to reddish, distally green or stramineous to reddish, membranous, apex often red, obtuse to acute, tooth absent.

3–8 × 1.5–4 mm;

proximal scale with a flower, seldom empty, 2–5 mm, 1/2 or more as long as spikelet;

floral scales 3–10 per spikelet, 2.5–6 × 1.5–2.5 mm.

ovoid, 1–4 × 1–2 mm, obtuse to acute;

proximal scale amplexicaulous, apex entire;

subproximal scale with flower;

floral scales spreading in fruit, 5–30, 8 per mm of rachilla, medium to very dark brown, midrib region often pale or greenish, broadly ovate, 1–1.3 × 1 mm, apex rounded, entire, not carinate.

perianth bristles (0–)3–6, often unequal, rudimentary to equaling tubercle, stout to slender, spinules dense to apparently absent;

anthers 1.5–2.7(–3.5) mm.

perianth bristles absent;

stamens 3;

anthers yellow, 0.3 mm;

styles 3-fid.

stramineous to medium brown or gray-brown, equilaterally trigonous to compressed-trigonous, rarely some biconvex, obpyriform (to obovoid), 1.6–2.3 × 0.7–1.3 mm, beak variable.

persistent after scales fall, to dark yellow-orange or brown, broadly obpyriform, trigonous, angles evident, 0.6–0.65 × 0.5–0.55 mm, rugulose at 20–30X, 20 blunt horizontal ridges in each vertical series.

rarely absent, 0.3–0.4 × 0.2–0.3 mm.

brown, greatly depressed, rudimentary, 0.05–15 × 0.15–0.3 mm.