Flora of North America species comparison

basally cormlike, trigonous, (15–)30–100 cm × 0.5–3.5 mm, glabrous.

solitary or not, trigonous or round, glabrous or scabridulous with extrorse or antrorse (rarely retrorse) prickles.

flat to V-shaped, 10–65 cm × 3–9 mm, adaxial surface, margins minutely scabridulous.

usually basal;

ligules absent;

blades keeled abaxially, flat, V-, or inversely W-shaped in cross section.

spikes densely globose to globose-ovoid, 8–17 mm wide;

rays 3–12, 2–12 cm, scaberous adaxially especially distally;

rachis 4–8 mm;

bracts (3–)4–7, ascending at 30(–45)°, flat, 5–35 cm × 2–9 mm;

rachilla persistent, wings 0.5–0.7 mm wide.

terminal, rarely pseudolateral, 1st order subumbellate to capitate, 2d order with spicate or digitately arranged spikelets, rarely a solitary spikelet;

spikelets 1–150; 1st order rays unequal (rarely equal) in length, produced singly from the axils of inflorescence bracts;

involucral bracts 1–22, spirally arranged at culm apex, spreading to erect, leaflike.

50–100, oblong-lanceoloid, ± terete-quadrangular, (3.5–)4–7 × 1–1.4 mm;

distal spikelet spreading or ascending;

floral scales persistent, 3–5, appressed, stramineous to brownish, 4-ribbed laterally, oblong-elliptic, 3.5–4.5 × 1–1.8 mm, membranous, apex entire or emarginate with mucro to 0.3 mm.

scales to 76, distichous, each subtending flower, cylindric to compressed, borne spicately or digitately at ends of rays (occasionally proliferous).

anthers 0.4–0.8 mm;

styles 0.5–0.6 mm;

stigmas 1 mm.

bisexual [rarely unisexual], in axils of distichous floral scales, bases often decurrent onto rachilla as ± hyaline wings;

perianth absent;

stamens 1–3;

styles linear, 2–3-fid, base deciduous or persistent;

stigmas 2–3.

brown, ± stipitate, oblong, (1.5–)1.8–2.3 × 0.5–0.6(–0.7) mm (1/2 length of floral scales), apex obtuse, surfaces puncticulate.

biconvex, flattened, or trigonous.