Flora of North America species comparison

trigonous, 30–150 cm × 1–5(–8) mm.

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

bladeless.

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

heads digitate, 15–30(–36) mm diam.;

rays (14–)20–22, (2–)5–12(–20) cm; 2d order rays 0.3–3(–4) cm; 3d order rays sometimes present, 0.3–2.5 cm;

bracts (4–)18–22, ± horizontal, flat, 15–27 cm × (1.5–)8–12 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.

8–20, ovoid to linear-lanceoloid, compressed, 5–25 × 1.5–2 mm;

floral scales 8–28, laterally whitish or light brown, ± hyaline, medially light brown, laterally ribless, medially 3-ribbed, 2-keeled in proximal 30–60%, deltate-ovate, 1.6–2.4 × (1–)1.2–1.5(–1.7) mm, apex acute.

(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 0.7–1 mm;

styles 0.5–1 mm;

stigmas 0.6–1 mm.

anthers (0.2–)0.3–0.4(–0.7) mm;

styles 0.4–0.7(–1) mm;

stigmas (1–)1.5–3 mm.

brown, sessile or stipitate, broadly ellipsoid, 0.6–0.8 × 0.4–0.6 mm, stipe if present to 0.1 mm, apex obtuse, apiculate, surfaces puncticulate.

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.