Flora of North America species comparison

terete.

4–40 cm × 0.2–0.5 mm.

all basal;

sheaths green to stramineous, sometimes reddish proximally;

ligules absent;

blades rudimentary to exceeding culms.

sometimes sparsely orange-punctate at 10–15X;

sheaths usually reddish proximally;

distal blade rudimentary to much longer than sheath, often exceeding culm, to 20 cm × 0.2–1 mm.

terminal, sometimes pseudolateral, capitate or solitary spikelet;

spikelets 1–3(–15);

involucral bracts 1(–2), spreading to erect, like foliage leaf blades.

involucral bract 1, sometimes subtending flower or resembling enlarged floral scale, 2–6(–23) mm.

scales 8–25, spirally arranged, each subtending flower.

2–5 × 1–2 mm;

scales partly or completely dark orange to red-brown, rarely stramineous, midrib greenish to stramineous, not gibbous, obscurely to prominently 3–11-veined, midrib keeled near apex, membranous, hyaline, apex rounded to acute, with mucro less than 0.1 mm;

proximal scale to 2 mm;

other scales 1.2–1.8 × 1–1.3 mm.

bisexual;

perianth absent;

stamens 1–3;

styles linear, 2–3-fid, base persistent, sometimes slightly enlarged.

anthers 0.3–0.6 mm;

styles 3-fid or 3-fid and 2-fid.

biconvex or trigonous, papillose or longitudinally ribbed.

falling separately from scales, medium to dark brown or stramineous, ellipsoid to obovoid, compressed-trigonous to thickly biconvex, lateral angles usually prominent, abaxial angle prominent to obscure, faces convex or adaxial face slightly concave, 0.8–1 × 0.5–0.7 mm, distinctly papillose at 10–15X to obscurely papillose at 40X, often with thin whitish surface layer.

= 30.