Flora of North America species comparison

1–15, trigonous, 7–30 cm × 1.2–2.5 mm, soft (flattened in pressing), glabrous.

trigonous, 30–100 cm × 2–4 mm, basally cormlike, glabrous.

2–7, flat, (2–)7–22 cm × 2.2–4 mm.

flat to broadly V-shaped, 20–70 cm × 4–6 mm, glabrous except for marginal prickles.

heads dense, 7–17 mm diam.; when rays short, heads sessile or nearly so, then densely irregularly lobate, 12–35 mm diam.;

rays 1–5, 2–32 mm;

bracts 2–4, longest bract erect or nearly so, appearing as continuation of culm, other bracts horizontal to ascending, 1–22 cm × 0.5–3.5 mm, margins and keel minutely scabridulous.

spikes loosely to densely ovoid, oblong (2 times long as wide), 10–12 × 6–9 mm;

rays 6–11, 1–16 cm, glabrous;

bracts 5–10, ascending at 30–45°, flat, 6–25 cm × 3–6 mm;

rachilla persistent, wings 0.5 mm wide, covering nearly entire length of achene.

30–120, greenish brown to purplish brown, oblong-ellipsoid, compressed, (2–)3–5(–6) × 0.8–1.2 mm;

floral scales (6–)12–20(–30), laterally clear margins, stramineous to deep purple, medially greenish, stramineous, or purplish, laterally ribless, medially 3-ribbed, obovate to orbiculate, 0.6–0.8 × 0.6–0.8 mm, apex mucronulate.

(20–)40–100(–120), proximal spikelets reflexed somewhat, distal ones divaricate, ± terete, lanceoloid, 6–6.8 × 1–1.4 mm;

floral scales persistent, 1–2(–3), appressed, golden brown, lanceolate, laterally 5–6-ribbed, 3.8–4.9 × 1.4–1.6 mm, apex mucronate, mucro at most 0.3 mm.

stamens 1 or 2;

anthers ovoid-ellipsoid, 0.1 mm, connective not prolonged;

styles 0.1 mm;

stigmas 0.1–0.3 mm.

anthers 1–1.3 mm;

styles 0.8–1 mm;

stigmas 2–3 mm.

light brown, obovoid-ellipsoid, 0.6–0.8 × 0.3–0.4 mm (as long as subtending scale), base cuneate, apex obtuse, apiculate, surfaces finely reticulate, papillose.

brown, sessile, linear, 2.5–2.8 × 0.5–0.7 mm, apex obtuse, apiculate, surfaces muriculate.