Flora of North America species comparison

trigonous, 5–25 cm × 1–1.5 mm, glabrous.

2–6, trigonous, (10–)35–80 cm × 0.5–2(–4) mm, scabridulous with retrorse prickles (infrequently glabrous or rarely also with extrorse prickles).

3–9, V-shaped, (12–)25–45(–65) cm × 2–10 mm;

blades and bracts without cross ribs.

spikes loosely ovoid, 15–25 mm wide;

rays 1–6, 2–7 cm;

bracts 2–5, 3–20 cm, ascending;

rachilla deciduous, winged.

heads umbellate, 10–20(–30) mm diam.;

rays 4–12, 1–6 cm, minutely scabridulous with retrorse prickles; 2d order rays often present, 1–2(–3) cm; 3d order rays rarely present, 0.5–1.5 cm;

bracts 3–8, approximately horizontal to ascending at 30°, V-shaped to flat, 2–15(–34) cm × 1–4(–5) mm.

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.

(6–)15–40(–65), greenish white, linear to linear-oblong, (3–)4–12(–15) × 1.5–2.5 mm;

floral scales 10–50(–65), laterally pale yellow, light brown, or reddish brown, 2-keeled, medially 3-ribbed, lanceolate, 1–1.5 × 0.8–0.9 mm, distinctly reticulate, often scabridulous near apex.

anthers 0.3–0.4 mm;

styles 1 mm;

stigmas 1.3–1.6 mm.

stamen 1;

anthers 0.5 mm;

styles 0.8–1.1 mm;

stigmas 0.5 mm.

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

brown to reddish brown, slightly stipitate, narrowly ellipsoid, 0.7–0.9 × 0.2–0.4 mm, apex apiculate, surfaces papillate or obscurely reticulate to rugulose.