Flora of North America species comparison

trigonous, 30–150 cm × 1–5(–8) mm.

trigonous, basally tuberous-thickened, (5–)15–40(–80) cm × 1–2.5 mm, glabrous.

bladeless.

flat to V-shaped, (5–)10–30(–60) cm × (0.5–)1–3(–4) 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.

spike 1, loosely to densely ovoid to cylindric, 8–36 × 8–20 mm;

rays 3–6(–9), (5–)10–32 cm;

bracts 3–6, horizontal to ascending at 30°, V-shaped, (1–)3–15(–30) cm × 0.5–4.5 mm;

rachilla deciduous, wings 0.5–0.7 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.

(5–)20–35(–65), linear to oblong (without narrowed basal portion), quadrangular; (2.2–)4–10(–18) × 0.7–1.1 mm;

floral scales persistent, 1–5, appressed, pale greenish white laterally, stramineous with reddish dots, or deep red, greenish or light brown medially, 3–6-ribbed laterally, narrowly ovate to oblong-elliptic, 2.6–3.9 × 1.6–2 mm, apex rounded to ± acute, entire, mucronulate;

distal scale with glabrous midrib and mucro 0.1–0.3(–0.5) mm;

sterile terminal scale of spikelet only 0.4–0.6 mm wide, involute, frequently uncinate.

stamens 3;

anthers 0.7–1 mm;

styles 0.5–1 mm;

stigmas 0.6–1 mm.

anthers (0.3–)0.4–0.6 mm;

styles 0.4–0.5 mm;

stigmas 0.5–0.9 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.

light brown to reddish brown, sessile or slightly stipitate, ellipsoid, (1.8–)2–2.4 × 0.6–0.8(–0.9) mm, apex slightly apiculate, surfaces puncticulate.