Flora of North America species comparison

trigonous, (10–)30–80(–140) cm × (0.4–)1–3(–5) mm, glabrous.

roundly trigonous, 20–50(–80) cm × 1–3 mm, glabrous.

V-shaped or flanged V-shaped, (5–)15–70(–90) cm × (2–)4–10(–13) mm, glabrous.

3–11, V-shaped, 12–40 cm.

spikes 1(–5), rather densely ovoid or oblong-cylindric, (10–)25–45(–62) × 7–22 mm, 11–21 spikelets per 5 mm of rachis;

rays (3–)5–10(–17), (1–)5–12(–24) cm;

bracts (2–)4–8, ascending at 30–45°, V- or inversely W-shaped, (2–)8–40(–65) cm × (1–)2–8 mm;

rachilla deciduous, wings 0.4–0.5 mm wide.

heads loosely to rather densely hemispheric, 15–30 mm diam.;

rays 5–10, 2–12 cm; 2d order rays occasionally produced, 5–25 mm;

bracts 4–8, approximately horizontal to ascending at 30°, V-shaped, 10–36 cm × 1.5–4 mm, margins glabrous.

(10–)50–150, oblong to linear, quadrangular, (3–)4–8(–18) × (0.8–)1–1.2(–1.6) mm;

distal spikelet spreading or ascending;

floral scales (1–) 3–8, pale greenish white to golden brown, deep brown, or reddish brown, medially usually green, weakly to strongly 3(–4)-ribbed laterally, 1–3-ribbed medially, ovate to elliptic, (2–)2.6–3.2(–4) × 1.2–2 mm, apex obtuse.

(4–)10–30, greenish, grayish, or stramineous, oblong to linear-oblong, compressed, (5–)7–10(–35) × 2–3 mm;

floral scales 10–25(–85), laterally yellowish brown, medially yellowish or brownish, laterally ribless, medially 2-ribbed with groove between ribs, broadly ovate (widest in proximal 1/2), (1.2–)1.5–2 × 1.2–2 mm, apex obtuse (declined (45–)60–90º from rachilla).

anthers (0.4–)0.6–1 mm;

styles 0.4–1.6 mm;

stigmas 1–1.5 mm.

stamen 1;

anthers oblong, 0.8–1.2 mm, connective not prolonged;

styles basally thickened, confluent with summit of achene, 0.6–1.2 mm;

stigmas 0.3–0.6 mm.

brown or reddish brown, sessile or nearly so, ellipsoid, 1.4–1.8(–2) × 0.6–0.8(–1) mm, apex acute to obtuse, slightly apiculate, surfaces puncticulate.

reddish brown to dark purplish brown, dull or more often iridescent, stipitate, broadly ellipsoid, 1–1.5 mm × 0.4–0.6(–0.7) mm, base cuneate to ± attenuate, stipe 0.1–0.2 mm, apex acute, beak 0.1–0.5 mm, surfaces reticulate with network of low ridges.