Flora of North America species comparison

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

trigonous, 2–30 cm × 0.6–1.1 mm, glabrous.

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

blades and bracts without cross ribs.

flat, 4–10 cm × 2–4 mm.

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.

rays 1–3, 0.2–1.5 cm; 2d order rays present in robust plants, to 5 mm;

bracts 2–3, longest erect, others spreading, 1–20 cm × 1.5–3 mm.

(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.

3–12, narrowly ellipsoid, flattened, 3–7 × 0.9–1.2 mm;

floral scales 8–12(–16), laterally purplish brown, medially greenish yellow, 3-ribbed medially, orbiculate, 0.9–1.1 × 1 mm, apex mucronate.

stamen 1;

anthers 0.5 mm;

styles 0.8–1.1 mm;

stigmas 0.5 mm.

stamen 1;

anthers ellipsoid, 0.2 mm, connective not prolonged;

styles 0.3–0.4 mm;

stigmas 0.3 mm.

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.

light brown, ellipsoid, 0.7–0.9 × 0.4 mm, base barely stipelike to narrowly cuneate, apex acute, surfaces glabrous.