Flora of North America species comparison

erect to excurvedascending, narrowly linear to ± filiform, terete to obscurely trigonous, leafy, densely so toward base, stiff to rather lax.

erect to ascending, leafiest at base, triangular, slender, somewhat stiff.

overtopped by culm;

blades linear, ascending, proximally flat, 1–4 mm wide, apex trigonous, subulate, tapering gradually.

exceeded by culm;

basal blades crowded, spreadingexcurved, distal ascending, linear, proximally flat, 3–5 mm wide, apex trigonous, shortsubulate.

spikelet clusters 1–3(–4), proximal mostly widely spaced, dense, broadly turbinate to hemispheric, to 2 cm broad; leafy bracts subulate, exceeding proximal spikelets, slightly or not exceeding most distal clusters.

spikelet clusters 3–5, compact, the proximalmost widely spaced, turbinate or lobed to hemispheric; leafy bracts setaceous, mostly overtopping clusters.

redbrown, narrowly ovoid, (3–)3.5–5 mm, apex acute;

fertile scales ovate, 3–3.5(–4) mm, apex acute, mostly with cusp or mucro 0.5–1 mm.

redbrown, broadly ovoid, 3–3.5(–4) mm, apex acuminate;

fertile scales broadly ovate to ± orbiculate, 2–2.5(–3) mm, apex rounded to notched, midrib included or shortexcurrent.

bristles 5–6, from rudimentary to reaching tubercle tip, or (rarely) beyond, antrorsely barbellate.

perianth bristles 6, reaching from fruit midbody to tubercle, antrorsely barbellate.

1–3 per spikelet, (1.5–)2–2.2(–2.5) mm;

body dark brown with pale center, lenticular, broadly ellipsoid to ± orbicular, (1.3–)1.5–1.7(–1.9) × 1–1.5 mm, margins pale, narrow or narrowly rounded, flowing to tubercle;

surfaces dull, minutely longitudinally striate;

tubercle compressed, triangular to triangularsubulate, 0.5–0.7(–0.9) mm.

1–2 per spikelet, (2–)2.5–2.8(–3) mm;

body brownish, broadly obovoid to nearly orbicular, 1.5–2 × 1.5–2 mm;

surfaces strongly transversely wavyrugose, intervals rows of vertical, rectangular alveolae;

tubercle conic-subulate, basal rim flaring above short neck on achene.