Flora of North America species comparison

10–30(–40) cm, bases hard, swollen.

(5–) 10–20 cm.

¼–1/2 length of scapes;

sheaths brown to stramineous, abaxially glabrous or hirtellous;

blades spreading to erect, filiform, wiry, less than 1 mm wide, involute, margins and adaxial surface glabrous to hispidulous or scabrid.

1/2–2/3 length of culms;

sheaths brownish to stramineous, glabrous or scabrid along ribs;

blades spreading-recurved, filiform, 0.5 mm wide, involute, margins and adaxial ribs hispidulous.

terminal, mostly in compound, compact or diffuse, involucrate anthelae;

scapes ascending to erect, wiry, 1 mm thick, coarsely ribbed, ribs glabrous or hispidulous to scabrid;

proximal bladed involucral bract exceeding or exceeded by inflorescence.

scapes erect to spreading, wiry, angularly ribbed, 0.6–1 mm thick, hispidulous;

spikelets in dense, terminal, top-shaped to hemispheric involucrate heads, 1–1.5 cm wide;

longer involucral bracts with setaceous blades many times exceeding heads, gradually dilating to scarious-bordered, entire sheaths.

red-brown to chestnut-brown, lanceoloid to cylindric, 4–6 mm, mostly longer than broad;

fertile scales ovate, curvate-keeled, 2–2.5 mm, apex acute, glabrous or papillose-puberulent, midrib excurrent as mucro or mucronula.

usually greenish or dull brown, oblong to lance-ovoid, 3–5 mm;

fertile scales ovate, keeled, 3–4 mm, abaxially hirtellous, midrib excurrent forming excurved mucro, scabrid.

stamens 3;

anthers linear, 1–2 mm.

stamens 1;

anthers oblong, 0.5 mm.

gray to yellow-brown or dark brown, trigonous-obovoid, 1–1.2(–1.5) mm, faces rugulose, papillate;

tubercle a globose button.

pale or graybrown, broadly trigonousobovoid, rather sharply 3-ribbed, 1 mm, faces flat or somewhat concave, finely transversely rugose;

tubercle a depressed-conic button.

= 60.

= 30.