Flora of North America species comparison

stoutly trigonous, thickened, 50–300 cm × 5–30 mm, basally indurate, glabrous.

trigonous, 30–50(–80) cm × 1.8–2.5 mm, glabrous.

V-shaped, with cross ribs, 40–130 cm × 10–15 mm, margins and keel scabrid.

4–7(–10), V-shaped, (20–)40–60 cm × 4.5–8 mm.

spikes appressed-ascending, narrowly cylindric, (2–)3–45 mm × (4–)7–10 mm;

rays (5–)9–12, 2–22(–30) cm; 2d order rays distinctly flattened, 1–10 cm; 3d order rays flattened, 0.5–3 cm;

rachis 2.5–4 cm;

bracts (6–)9–10, ascending at 45–75°, V- or inversely W-shaped, (5–)15–90 cm × 0.5–20 mm;

rachilla persistent, wings 0.2–0.4 mm wide.

heads dense, hemispheric, 7–15(–18) mm diam;

or if rays absent, heads dense, irregularly lobate, 2–3.5 cm diam.;

rays 3–6, 1–30 mm; 2d order rays infrequently present, to 5 mm;

bracts (5–)10–15(–40), horizontal to ascending at 30(–45)°, V-shaped, 6–30(–40) cm × 5–8(–10) mm.

(4–)10–35, appressed-ascending, compressed, linear, 7–12(–15) × 0.6–1.2 mm;

floral scales deciduous, 6–20, marginally clear, laterally brown, medially green, laterally 2–3-ribbed, medially 1-ribbed, oblong-ovate, (3.2–) 3.8–4.3 × 1.2–1.7 mm, apex spreading, acute to obtuse, mucronulate.

40–100, greenish white, flattened, ovoid, 3.5–5 × 3–4 mm;

floral scales (8–)12–16, uniformly light greenish to light brown, laterally 1-ribbed, medially indistinctly 3-ribbed, basally 2-keeled, oblong-spatulate, widest at or above median, 2–2.5 × (0.7–)1–1.2 mm, apex minutely mucronate, scabridulous, infrequently glabrous.

anthers 0.7–0.9 mm, connective apex bright red, oblong, to 0.1 mm;

styles 0.8–1.3 mm;

stigmas 2–3.3 mm.

stamen 1;

anthers oblong, 0.7–1 mm, connective apex subulate, prolonged 0.1–0.2 mm;

styles thick, confluent with apex of, and persistent on, achene, 0.5–0.8 mm;

stigmas 0.6–1 mm.

brown, sessile, narrowly ellipsoid, 1.8–2.5 × 0.8–1.3 mm, apex ± acute, not apiculate, surfaces puncticulate.

brown, stipitate, linear, slightly curved, 1.2–1.4 × 0.2(–0.3) mm, base whitish, stipe spongy, 0.1–0.2 × 0.2 mm, apex acute, surfaces papillose.