Flora of North America species comparison

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

subcylindric, 0.2–1.5 m × 0.5–1 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.

3–20+, smooth;

sheath fronts sometimes delicately pinnate-fibrillose;

blades 3–20, when erect C-shaped in cross section proximally, elliptic most of length, when submerged usually flaccid and filiform to narrowly ribbonlike, probably longer than sheath, 0.2–1 mm wide.

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

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

a solitary, erect spikelet;

proximal bract erect, like stiff leaf blade, 7–60 mm.

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.

5–15 × 3–7 mm;

scales pale brown, or central region green when young, ovate-lanceolate, 4–6 × 1.5 mm, smooth, margins sometimes ciliolate apically at 40X, midrib obscure, apex acute, entire, minutely mucronate.

perianth absent;

anthers 0.3–0.5 mm;

styles 3-fid.

perianth members 6, brown, bristlelike, from 1/2 of to equaling achene beak, spinulose;

anthers 2–3.5 mm;

styles 3-fid.

brown, strongly trigonous, obovoid to obpyriform, (2.5–)3–3.5 × 1.5–1.7 mm;

beak 0.3–0.8 mm.

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

= 50.

= 72.