Flora of North America species comparison

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

erect, slender, leafy-based, trigonous, several-ribbed.

exceeded by culm;

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

spreading to erect, overtopped by culm;

blades narrowly linear, proximally flattened, 0.5–3 mm wide, apex tapering, trigonous.

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

terminal, solitary, headlike, dense, white, leafy-involucrate;

involucral bracts several, flaring to recurved, white from broadened base nearly to median, then green to tapered tip, longer bracts 13 cm × 2–7 mm.

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.

white, ovoid, 5–7 mm, apex acute;

fertile scales many, boatshaped, sharply curvedkeeled, 3–4(–5) mm, apex acute or blunt.

bristles 6 or vestigial, rarely reaching fruit midbody, antrorsely barbellate.

perianth absent.

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.

several per spikelet, 1.5–1.7(–2) mm;

body yellow to mahogany, broadly pyriformobovoid, tumidly lenticular, 1 × 0.5–0.7 mm, widest at apex, margins thickened, interrupted at base of tubercle;

surfaces transversely undulaterugose, ridges contiguous, of shortlinear papillae;

tubercle broadly triangular, 0.5–0.6 mm, graycrustaceous, apex short acuminate.

= 12.