Flora of North America species comparison

to 45 cm × 0.2–1 mm.

sometimes arched, smooth or obscurely 4- or 5-angled or -ridged, terete or slightly compressed, 6–25 cm × 0.15–0.3 mm, soft to firm.

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

distal leaf sheaths persistent, red proximally, colorless distally, closely sheathing, apex blunt.

orbicular to ovoid, 1–9 × 1–4 mm, apex rounded to acute;

proximal scale without flower, not amplexicaulous;

floral scales to 125, 11–14 per mm of rachilla, tightly appressed, dark red-brown to stramineous, ovate to elliptic, 0.8–3 × 0.6–2(–2.3) mm, membranous to cartilaginous, apex rounded to acute.

ovoid, 2–6 × 1–2 mm, apex acute;

scales 5–15, 5 per mm of rachilla, bright red-brown, midrib region green to stramineous, ovate, 1.5–1.7 × 1 mm, midrib keeled to obscure, apex blunt to acute.

perianth bristles (0–)4–8, typically 7, red-brown, rarely whitish, vestigial to much exceeding tubercle, typically equaling achene, spinules few to dense;

styles 2-fid.

perianth bristles absent;

anthers 0.5–1 × 0.2 mm.

brown ripening to black, biconvex, orbicular to obpyriform, 0.5–1.1 × 0.3–0.7 mm, apex rarely constricted proximal to tubercle, very finely reticulate at 40X.

with angles plus longitudinal ridges ca. 8–9, obscure to rather prominent, obovoid to obpyriform, much less than 2 times longer than wide, 0.55–0.6 × 0.3–0.4 mm, trabeculae 20–30, rather obscure and crowded.

stramineous to whitish, umbonate to subconic, 0.2–0.4 × 0.2–0.5 mm, apex rounded to acute.

brownish to whitish, pyramidal to depressed, 0.1–0.15 × 0.1–0.2 mm.

= 10.