Flora of North America species comparison

roundly trigonous, basally with dark fibrous remnants of old leaf sheaths, (0.5–)4–30 cm × 0.4 –1.1 mm, glabrous.

trigonous, 50–150 cm × 2–15 mm, glabrous (rarely sparsely scabridulous on angles proximal to bracts).

1–5, flat, involute toward apex, 3–18 cm × 1–2.5(–3) mm.

inversely W-shaped, 40–100 cm × 5–15 mm.

heads hemispheric to spheric, (3–)6–15(–24) mm diam.;

rays absent;

bracts 2–5, horizontal to reflexed, parallel to culm, 1–13 cm × 1–3 mm, margins and keel sparsely minutely scabridulous distally.

spikes 1–4, cylindric, (2.5–)3.5–5 × 1.2–1.5 cm;

rays 8–10, (1–)15–35 cm; 2d order rays 1–3 cm;

bracts 8–12, ascending at 45–60°, (5–)20–80 cm × 3–15 mm; 2d order bracts 3–7 cm × 2–4 mm;

rachilla persistent, wings 0.3 mm wide, at achene maturation adaxial edge of wing detaching from rachilla, base remaining firmly attached.

(5–)20–60(–100), whitish to greenish or brownish, ovoid to oblong-lanceoloid, compressed, 3–7 × 2–4 mm;

floral scales (8–)10–12(–24), laterally milky white (infrequently yellowish, pale greenish, brown, or bronze-white), medially green or white, laterally ribless, medially 3-ribbed, ovate to ovate-lanceolate, 1.6–3(–3.4) × 0.8–1.3 mm, apex mucronate to acuminate.

35–65, slightly compressed, linear, ± quadrangular, 5–8 × 0.8–1.1 mm;

floral scales deciduous, 12–16, appressed, marginally clear, laterally reddish along midrib, medially green, laterally 1–2-ribbed, medially strongly 5-ribbed, ovate, 1.6–1.8 × 1.1–1.3 mm, apex mucronulate.

stamens 3;

anthers linear, (0.4–)0.6–0.8(–1.1) mm, connective not prolonged;

styles 0.8–1.8 mm;

stigmas (0.5–)1–1.5(–2) mm.

anthers 0.4–0.5 mm, connective blunt, at most 0.1 mm;

styles 0.8–1 mm;

stigmas 0.4 mm.

brown to blackish, trigonous, broadly obovoid, 0.5–1 × 0.3–0.75 mm, base slightly stipelike, ± cuneate to rounded, apex apiculate, papillose.

brown or whitish, sessile, ellipsoid, slightly wider at base, 0.9 × 0.4 mm, surfaces finely puncticulate.