Flora of North America species comparison

erect to spreading-ascending, leafybased, trigonous or compressed, ribbed.

lax, leafy, mostly excurved, slender.

exceeded by scape;

blades narrowly linear to filiform, 0.2–2 mm wide, apex tapering, trigonous.

shorter than culm;

blades ascending, narrowly linear, proximally flat, 2–4(–5) mm wide, apex trigonous, short-subulate, tapering.

terminal, solitary, headlike, dense, white, leafyinvolucrate, hemispheric to globose, 0.5–1.5 cm wide;

involucral bracts (0–)1–4, ascending to recurved, green, (0.7–)2–5(–6) cm × 0.2–2 mm.

spikelet clusters 3–7(–10), dense, all but most distal widely spaced, broadly turbinate to ovate or hemispheric.

white, ovoid, 5–7 mm;

fertile scales several, boat-shaped, 2.5–3.5 mm, keel curved, not sharp.

light red-brown, lanciform, 5 mm, apex acuminate;

fertile scales lanceolate, 4–4.5 mm, apex acuminate, midrib excurrent as awn.

perianth absent.

bristles 6, reaching past tubercle base, usually to or slightly past its tip, antrorsely barbellate.

0.8–1 mm;

body yellow to near black, broadly pyriform-obovoid, tumidly lenticular, 0.5–0.8 × 0.5–0.8 mm, margin narrow, flowing into tubercle;

surfaces transversely sharply wavyrugose, ridges bordered by rows of fine, linear, vertical lattices;

tubercle depressedtriangular, lunate-based, shortbeaked 0.2(–0.3) mm, gray-crustaceous.

2(–4) per spikelet;

stipe and receptacle curled-setose, (0.5–)0.6–08(–1) mm;

body glossy, brown with pale center, narrowly obovoid-lenticular, 1.2–1.5 mm, surfaces minutely striate, sometimes transversely minutely rugulose with wavy rows of dark minute dots;

margins narrow, strong, flowing to tubercle;

tubercle narrowly triangular, slightly concave-sided, flattened, setulose-ciliate, 0.7–1.1 mm.