Flora of North America species comparison

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

erect to arching or spreading, leafy, ± filiform, ± terete, stiff to rather lax.

exceeded by scape;

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

exceeded by culm;

blades linearfiliform, proximally shallowly concave, 1 mm, apex tapering, trigonous, blunt or broadly acute.

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 1–2, mostly compact, turbinate to hemispheric; leafy bracts setaceous, exceeding spikelet clusters.

white, ovoid, 5–7 mm;

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

dark redbrown, ovoid, 2–3 mm, apex acute;

fertile scales obovate, 1.5–1.7(–2) mm, apex broadly rounded or retuse, midrib excurrent as cusp or mucro to 0.5 mm.

perianth absent.

bristles 6 or vestigial, rarely reaching fruit midbody, 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.

1–2 per spikelet,1.7–2 mm;

body brown with large pale center, lenticular, broadly obovoid to ± orbicular, 1.2–1.5 × 1.4–1.6 mm;

tubercle flat, triangular, concave-sided, 0.4–0.6 mm, sometimes apiculate.