Flora of North America species comparison

trigonous or ± terete, (3–)20–45(–70) cm × (0.8–) 1.2–2 mm, glabrous.

to 25 cm apart, 1(–3) together, terete (scarcely compressed in drying), occasionally trigonous for apical 1/3, 40–140(–200) cm, 4–12 mm thick at base, (1.2–)1.5–2.5 mm thick at apex (with conspicuous transverse septa ca. 3 cm apart basally, to 3–5 mm apart apically), glabrous or infrequently scabrid on angles apically;

sheaths at base of culm, 2–3, (5–)10–25 cm, loose, papery.

(2–) 6–10(–16), flat to V-shaped, (2–) 10–30(–60) cm × 1–4 mm.

usually bladeless, blades when present, cross ribs prominent, especially adaxially, (1–)10–20(–40) cm × 4–6(–9) mm.

spike 1, loosely ovoid to densely turbinate, 12–40 × 10–25 mm;

rachis 3–10 mm;

rays 1–8(–12), 0.5–3(–6) cm; 2d order rays absent;

if rays absent, inflorescence single dense cluster of spikelets, 12–40 mm diam.;

bracts (3–)4–6(–7), horizontal to ascending at 45°, flanged V-shaped, (2–)5–15(–23) cm × 1–4 mm.

spikes 1(–5), broadly ovoid to ± umbellate, 15–45 × 10–30 mm;

rays 5–7(–10), 0.3–8(–12) cm; 2d order rays occasionally present, 5–20 mm;

bracts 2(–4), erect, longest appearing to be continuation of culm, deltate to lance-linear, 0.2–2(–9) cm × 1.5–4.5 mm;

rachilla persistent, wings translucent, whitish, or stramineous, 0.4 mm wide.

(5–)15–30(–40), spreading to appressed-ascending, linear-lanceoloid to linear, compressed, 8–18(–40) × (1–)1.3–1.6(–2) mm;

floral scales (8–)12–25(–66), laterally stramineous to light brown, medially green, laterally ribless, medially 3–5-ribbed, oblong, (1.5–)1.8–2.4 × (1–)1.2–1.4 mm, apex acute to ± acute, mucronate.

(1–)5–10, linear, compressed, 10–35(–45) × 1.1–2 mm;

floral scales deciduous, 15–45, spreading or appressed, laterally light brown, medially green to brown, laterally 1–2-ribbed, medially 3-ribbed, oblong-elliptic to ovate, 2.9–3.7 × 1.1–1.6(–1.8) mm, apex acute.

stamens 2;

anthers (0.4–)0.5–0.8 mm, connective not prolonged;

styles 0.6–1(–1.4) mm;

stigmas (1–)1.4–2 mm.

anthers 1.7–2.4 mm;

styles 1.2–3.6 mm;

stigmas 1.7–6 mm.

light to dark brown, oblong, (0.8–)0.9–1.1(–1.2) × 0.4–0.5(–0.6) mm, base cuneate to ± stipelike, apex truncate, apiculate, surfaces punctate to minutely punctate with raised cells.

brown, stipitate, obovoid-ellipsoid, 1.2–1.6 × 0.4–0.6 mm, stipe 0.1 mm, apex markedly apiculate, surfaces puncticulate.