Flora of North America species comparison

basally swollen and cormlike, trigonous, (1–)20–40(–90) cm × 1–6 mm, glabrous or few prickles subapically.

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

flat, (10–)20–40 cm × 1–4(–8) mm, margins and midribs glabrous or scabridulous.

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

spikes 1–4, loosely ovoid to oblong-cylindric; (6–)10–28(–50) × 10–40 mm;

rays sometimes absent, usually (1–)3–6(–8), 0.5–7(–25) cm;

if absent, inflorescence a congested head; 2d order rays sometimes present, 1–4(–9) cm;

rachis 8–18(–25) mm;

bracts (3–)5–7(–10), ascending at 30–45°, cross ribs sometimes conspicuous, (1–)10–30(–45) cm × (1–)2–4(–12) mm;

rachilla ± deciduous, wings 0.4–0.5 mm wide.

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.

(5–)12–50, linear-lanceoloid, compressed, 5–30 × 0.6–0.9 mm;

floral scales ± deciduous, 3–11, appressed, medially green, laterally stramineous to pale brown, 3–4-ribbed laterally, (1–)3-ribbed medially, oblong-obovate, 3.2–4.5(–6) × 1–1.8 mm, apex ± acute, overlapping lower 1/4–1/2 of next scale.

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.

anthers 0.3–0.5 mm;

styles 1–2 mm;

stigmas 3–4 mm.

anthers 0.6–0.8 mm;

styles 0.4–0.8 mm;

stigmas 1.2–2.2 mm.

purplish brown, ± stipitate, narrowly oblong, (1.5–)1.8–2.4 × 0.5–0.6 mm, apex apiculate, acute, 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.