Flora of North America species comparison

trigonous, compressed, 15–75 cm × 0.5–3 mm, glabrous.

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

1–3, 5–30 cm × 1–2 mm.

3–11, V-shaped, 12–40 cm.

spikes 1(–2), ovoid, 5–23 × 9–21 mm;

rays 2–3(–4), 0–15 mm;

if rays absent, head single, compact, sessile, (12–)15–20 mm diam.;

bracts 2–3, horizontal to vertical, 2–14 cm × 0.5–3.5 mm.

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.

1–6, oblong-lanceoloid, 5–26 × 2–3 mm;

floral scales 12–54, closely imbricate, laterally yellowish brown, medially pale brown, occasionally greenish, laterally 1-ribbed, medially 3-ribbed, distinctly 2-keeled basally, ovate, 1.8–2.6 × 1.4–1.7 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).

stamens 2;

anthers 0.4–0.5 mm, connectives not prolonged;

styles 0.3–1 mm;

stigmas 0.6–0.8(–1) 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, network of ridges forming isodiametric or square cells, stipitate, obovoid to ellipsoid, 1.1–1.3 × (0.5–)0.6 mm, apex acute to broadly rounded, surfaces minutely punctate or finely papillose.

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.