Flora of North America species comparison

2–12(–19) cm × 0.2–0.4 mm.

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 as wide as thick, (5–)10–40 cm × 0.5–1.2 mm, firm to hard, finely many-ridged at 10–20X;

culm tufts not proximally bulbous.

distal leaf sheaths firm, distally tightly sheathing, apex acute.

distal leaf sheaths stramineous to brown or reddish proximally, green to stramineous distally, subtruncate to obtuse, membranous to papery;

apex brown to red.

ovoid to ellipsoid, 2–6(–8) × 1–2.5 mm, apex acute;

proximal scale with or without flower, not amplexicaulous;

floral scales to 100, 15–19 per mm of rachilla, often loosely appressed, dark red-brown to stramineous, ovate to elliptic, 0.6–1.3 × 0.3–0.7 mm, membranous, apex rounded to acute.

5–10 × 2–4 mm;

proximal scale usually empty, 3–5 mm, usually 1/2 or more as long as spikelet;

floral scales 8–12 per spikelet, lanceolate (to ovate), 3.5–5 × 2–2.5 mm.

perianth bristles (0–)4–6, typically 4, colorless to whitish, vestigial to 1/2 as long as achene, smooth or spinuliferous;

styles 2-fid.

perianth bristles 6, equal, the longest equaling achene to exceeding tubercle, very slender, spinules dense;

anthers 1.6–3.5 mm.

black, obovoid, biconvex, 0.3–0.5 × 0.3–0.4 mm, apex often constricted proximal to tubercle, smooth at 40X.

medium brown to gray or dark brown, equilaterally trigonous to compressed trigonous, rarely some biconvex, 2–2.7 × 0.7–1.3 mm, apex tapered to a distinct stramineous beak 0.2–0.9 × 0.3–0.6 mm.

stramineous to whitish, umbonate to subconic, 0.1–0.2 × 0.1–0.2 mm, apex acute.

0.4–0.5 × 0.3–0.5 mm.

= 20.