Flora of North America species comparison

(10) 30-110 cm, round or basally compressed, tillering from the basal nodes, not branching from the aerial nodes, mostly glabrous, sometimes pilose basally;

internodes solid.

(12)20-125 cm, mostly erect, often strongly compressed, branching;

internodes hollow.

sometimes with a pilose collar;

ligules 1-2 mm, truncate, erose;

blades (2)8-35 cm long, 2-8 mm wide, glabrous, strigose, or pilose.

glabrous, smooth to scabrous;

ligules 1.5-2 mm, membranous, truncate, erose;

blades 25-35(50) cm long, 8-16 mm wide, scabrous on both surfaces.

8-20 cm, with 2-15 subdigitate or racemose branches;

secondary panicles often hidden in the lowest leaf sheaths;

branches 2-19 cm, ascending to spreading at maturity.

8-35 cm, with 50-150 racemose branches;

branches (2)5-12 cm, lax, sometimes arcuate, lower branches often remaining enclosed in the upper leaf sheaths.

4-12 mm, light brown to dark olive green, with 4-13 florets, often widely diverging at anthesis.

3-4.5 mm, usually tightly imbricate, green but straw-colored when dry, with 2-6 florets.

narrowly triangular to ovate, acute;

lower glumes 2.3-4.8 mm;

upper glumes 3.3-6 mm;

lemmas 3.5-5 mm, membranous, ovate to obovate, lateral veins glabrous or sericeous, hairs often restricted to the basal portion, sometimes also sericeous on the midvein and between the veins, apices obtuse to truncate, usually emarginate, unawned, sometimes mucronate;

paleas ciliate on the margins;

anthers 3, 0.3-1.6 mm.

sometimes mucronate;

lower glumes 0.8-1.6 mm, narrowly triangular to lanceolate;

upper glumes 1.1-2.1 mm, ovate;

rachilla segments not visible between the florets;

lemmas 2.1-2.4 mm, lanceolate to narrowly ovate, membranous, sparsely sericeous along the lateral veins, apices acute, unawned;

anthers 0.2-0.4 mm.

1.5-2.3 mm long, 0.9-1 mm wide, strongly dorsally compressed.

0.8-1.3 mm long, 0.3-0.5 mm wide, elliptic to obovate, depressed obovate in cross section.

= 40, 60, 80.

= 60.