Flora of North America species comparison

trigonous, 5–25 cm × 1–1.5 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.

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

spikes loosely ovoid, 15–25 mm wide;

rays 1–6, 2–7 cm;

bracts 2–5, 3–20 cm, ascending;

rachilla deciduous, winged.

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.

5–30, linear, flattened, 6–22 × 1.5–2.2 mm;

floral scales ± deciduous, (4–)8–12, red, reddish purple, or reddish brown, medially green, elliptic, laterally 2–4-ribbed, 2.3–3.1 × 1.2–2 mm, apex acute to obtuse.

(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.

anthers 0.3–0.4 mm;

styles 1 mm;

stigmas 1.3–1.6 mm.

anthers 1.7–2.4 mm;

styles 1.2–3.6 mm;

stigmas 1.7–6 mm.

brown to dark purplish brown, broadly ellipsoid, 1–1.3 × 0.6–0.9 mm, surfaces puncticulate.

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