Flora of North America species comparison

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

trigonous, (4–)10–50(–130) cm × (0.5–)1–4 mm.

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

flanged V- or inversely W-shaped, 5–30(–60) cm × 4–12 mm.

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.

spikes 1–5(–12), loosely to densely cylindric, ovoid, or ± pyramidal, 10–20(–40) × (8–)10–30(–35) mm;

rays (0–2)6–9(–12), 2–8(–13) cm;

if rays absent, infloresence a single dense, capitate cluster of closely imbricate spikes;

bracts (4–)5–8(–10), horizontal to ascending at 30–60°, (3–)10–25(–55) cm × 1–14 mm;

rachilla hyaline or thickened bronze, carmine, or yellowish, wings clasping achene.

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.

(10–)20–60(–100), linear-oblong to narrowly linear, cylindric to slightly flattened (when scale tips spreading), (5–)8–15(–38) × 0.8–1.3(–1.9) mm;

floral scales (4–)8–12–(30), medially green, laterally reddish to stramineous to shiny brown or beige, medially 2–5-ribbed, laterally 1–3-ribbed, ovate to elliptic, (2–)2.2–2.8(–3.2) × (1.2–)1.4–1.6(–1.8) mm, apex entire or emarginate with mucro to 0.3 mm.

stamens 3;

anthers 0.3–0.5 mm;

styles 0.4–0.9 mm;

stigmas 0.5–0.8(–1.3) mm.

anthers (0.2–)0.3–0.4(–0.7) mm;

styles 0.4–0.7(–1) mm;

stigmas (1–)1.5–3 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, reddish brown, or black, stipitate, narrowly ellipsoid to oblong (rarely obovoid-oblong), (1–)1.2–1.5(–1.9) × 0.5–0.6(–0.75) mm, stipe 0.1–0.2 mm, apex acute to barely obtuse, surfaces finely papillose.