Flora of North America species comparison

trigonous, (2–)25–60(–100) cm × 1–4 mm, soft (flattened in drying), glabrous.

trigonous, (15–) 20–40(–65) cm × 0.5–1 mm, glabrous.

usually reduced to sheaths, occasionally with blades, flat to V-shaped, (3–)10–30 cm × (1–)2.5–5 mm.

V-shaped, (10–)20–40 cm × 0.8–2.8(–3) mm, glabrous.

heads loosely digitate;

rays (5–)10–12(–15), 1–15(–20) cm; 2d order rays usually present, (1–)6–12(–25) mm; 3d order rays sometimes present, 1–6 mm;

bracts 2(–3), horizontal to ascending at 30–60°, longer (3–)6–18 cm × 2–4 mm, shorter (0.5–)2.5–6.5 cm × 1–2(–3) mm.

spike 1, densely oblong-cylindric, (15–)25–35(–40) × 12–18(–22) mm, (spikelets loosely spaced, 7–9 per 5 mm of rachis);

rays (5–)6–8(–11), 0.5–4(–7.5) cm;

bracts (4–)5–7(–8), ascending at 30º, (4–)10–30(–35) cm × (1–)2–4(–7) mm;

rachilla deciduous, wings persistent, 0.4–0.5 mm wide.

1–15, linear-lanceoloid, ± compressed-quadrangular, 3–18 × 1–1.6 mm;

floral scales 10–20(–40), laterally reddish to greenish brown, dull, often clear-edged, medially greenish, laterally 1-ribbed, medially 1-ribbed, oblong to obovate, 1–1.5(–1.9) × 0.8–1 mm, apex mucronate, glabrous except for cluster of crystalline prickles at apex.

(20–)40–80(–100), linear, ± cylindric, scarcely compressed, (4.5–)6–9(–11) × (0.5–) 0.6–0.7(–1) mm;

floral scales persistent, (1–)2–3(–4), appressed, medially green, laterally light brown to tawny or bronze, medially (1–)3-ribbed, laterally 3-ribbed, oblong, (2.6–)2.8–3.2(–3.4) × (1–)1.2(–1.4) mm, apex acute, mucronulate, mucro to 0.1(–0.2) mm.

stamens 3;

anthers 0.3–0.5 mm;

styles 0.4–0.9 mm;

stigmas 0.5–0.8(–1.3) mm.

anthers 0.6–0.8 mm;

styles (0.4–)0.6–1(–1.2) mm;

stigmas persistent on achenes, prominently exserted from floral scales, (1.5–)2–3(–4) mm.

white or reddish brown, stipitate, globose to obovoid or ellipsoid, 0.5–0.6(–0.7) × 0.3–0.4(–0.5) mm, base nearly cuneate, stipe 0.1 × 0.1–0.2 mm, apex obtuse to acute, apiculate or entire, surfaces granular to papillose.

brown to reddish brown, stipitate, narrowly oblong, 1.8–2.1 × (0.4–)0.5(–0.7) mm, stipe 0.1–0.2 × 0.1–0.2 mm, apex apiculate, acute, surfaces puncticulate.