Flora of North America species comparison

diffuse, very fine.

stiff or flaccid, usually terete, ribbed.

to 40 cm, wiry.

basal, polystichous, spreading to ascending;

sheaths open apically, apex fimbriate-ciliate, rarely entire;

ligules absent, lateral tufts of hair at junction of blade and sheath;

blades mostly linear or filiform, coarsely ribbed, usually longer than sheaths, 1 mm wide or less, mostly strongly involute, margins variably scabrid-ciliate.

¼–1/2 length of culms;

sheaths stramineous to tan or brown, glabrous or scabrid on ribs;

blades spreading to ascending, filiform, 0.5 mm wide, involute, margin glabrous or scabrid, abaxially glabrous or hirtellous.

terminal on slender scapes, rarely axillary to culm leaves, simple or compound anthelae or spikelet solitary;

spikelets 1–50+;

involucral bracts (1–)2–8, spreading or erect, leaflike or scalelike.

terminal, in simple or compound anthelae;

scapes wiry, coarsely ribbed, glabrous or strumose-puberulent;

longer primary involucral bracts with setaceous blades exceeding or exceeded by inflorescence.

mostly ovoid to lanceoloid or lance-cylindric;

scales 6–50, spirally arranged, rarely nearly distichous, each subtending flower or 1–2 proximal scales empty.

red-brown to dark brown, lanceoloid to cylindric, longer than wide, 2–6 mm;

fertile scales broadly ovate, keeled, 1–1.3 mm, apex acute, abaxially puberulent, midrib included or excurrent as mucro.

bisexual;

perianth absent;

stamens 1–3;

styles slender, (2–)3-fid, glabrous, base enlarged, persistent in fruit.

stamens 2–3;

anthers narrowly oblong, 0.8–1 mm.

trigonous or 3-lobed, rarely biconvex, usually 3-ribbed.

mostly waxy gray, trigonous, obovoid, 0.8–1.5 mm, faces evenly papillate, finely rugulose or level;

tubercle a small, dark, compressed-conic button.