Flora of North America species comparison

trigonous, 30–150 cm × 1–5(–8) mm.

trigonous, (20–)30–120 cm × 1.4–3.5 mm, glabrous or occasionally with scattered prickles on distal angles.

bladeless.

2–4(–6), inversely W-shaped, 10–60(–70) cm × (2–)4–13 mm, margins and midribs scabridulous or glabrous.

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–)3–6, narrowly cylindric, 1–4(–6) cm × 5–11 mm;

rays 0 or 3–6, 2–23 cm;

bracts 5–8, ascending at ± 45°, inversely W-shaped, (4–) 14–40(–46) cm × 1–12 mm;

rachilla deciduous, wings persistent, 0.3–0.5 mm wide.

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.

35–100, oblong-ellipsoid, ± terete, elliptic in cross section, 3–7 × (0.9–) 1.3–2 mm;

distal spikelets spreading or ascending;

floral scales persistent, 1–2(–5), appressed, becoming clear at maturity, laterally brownish to reddish brown, medially greenish, laterally 3–5-ribbed, medially 3-ribbed, often erose at maturity, ovate to elliptic, 2.2–3.2 × 1.5–2.1 mm, apex obtuse.

stamens 3;

anthers 0.7–1 mm;

styles 0.5–1 mm;

stigmas 0.6–1 mm.

anthers 0.6–0.8 mm;

styles 0.4–0.8 mm;

stigmas 1.2–2.2 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 to reddish brown, sessile, broadly ellipsoid, slightly dorsiventrally flattened, 1.5–1.8 × 0.7–0.9(–1) mm, apex obtuse, apiculate, surfaces papillose to puncticulate.