Flora of North America species comparison

often arching, sometimes spotted or streaked red-brown, quadrangular or broadly elliptic, sulcate or not, 0.5–25(–30) cm × 0.1–0.4 mm, soft.

obscurely 3–5-angled to terete, 40–110 cm × (2–)3.6–7.5 mm, soft, not septate-nodulose, internally spongy, transverse septa incomplete;

plants never forming filiform, flaccid culms.

distal leaf sheaths persistent or disintegrating, stramineous, green, red-brown, or spotted or streaked red-brown, membranous, translucent, apex obtuse or acute.

distal leaf sheaths persistent, membranous, apex acute to long-acuminate, sometimes prolonged into a slender bladelike portion to 6 cm.

basal spikelets usually present, pistillate; often proliferous, ovoid, ellipsoid, or linear, clearly laterally compressed, 2.3–6.9 × 0.5–2 mm, apex acute, proximal scale empty, amplexicaulous, similar to floral scales (midribs sometimes more prominent and sometimes slightly prolonged beyond lamina);

subproximal scale with a flower;

floral scales clearly distichous, 3–9, 3–4 per mm of rachilla, yellowish, pale brown, or red-brown, spotted, streaked, or mottled red-brown, narrowly ovate to oblong, (1.5–)2–5 × 0.4–0.6(–1.2) mm, membranous, apex rounded, obtuse or rarely acute, midribs keeled.

not proliferous, 12–43 × 3.5–6 mm;

rachilla joints bearing obscure winglike remnants of floral scales;

proximal scale without a flower, amplexicaulous, 3.6–7.5 mm;

floral scales 30–125, 1–3 per mm of rachilla, greenish to pale brown, often with pale to dark brown submarginal band or a subapical darker spot, ovate to oblong, 4.3–5.8 × 2.5–3.3 mm, cartilaginous, often membranous toward margins, margins broadly translucent, membranous, apex rounded to acute.

perianth bristles 3–7, incurved, colorless, white, or red-brown, shorter than or equaling achene;

spinules sparse, retrorse, sharply acute;

stamens 3;

anthers 1.4–2.2 mm;

styles 3-fid.

perianth bristles 6–7, stramineous, margins and spinules reddish to pale brown, stout, flattened, subequal, exceeding achene, 2.5–3.2 mm, coarsely retrorsely spinulose;

anthers reddish brown, 1.5–1.9 mm;

styles 3-fid or sometimes 2-fid.

whitish or greenish, spotted dark green, obovoid, trigonous, angles prominent, 0.6–0.9 × 0.4–0.6 mm, apex constricted proximal to tubercle, smooth to finely cancellate at 10–20X.

pale brown, biconvex, obpyriform, 1.7–2.3 × 1.2–1.5 mm, clearly sculptured at 10–15X, each face with 10–15 rows of transversely elongated cells, often isodiametric at achene base, apex usually constricted to neck 0.5–0.6 mm wide.

pale to red-brown, pyramidal, trigonous, 0.2–0.3(–0.4) × 0.2–0.5 mm.

stramineous, lamelliform to high-pyramidal, 0.8–1.1 × 0.7–0.9 mm.