Flora of North America species comparison

30-120 cm, erect, unbranched.

(60)70-100 cm, stiffly erect, unbranched.

basal and cauline, pale green, sometimes glaucous;

sheaths longer or shorter than the internodes, glabrous except at the summit;

collars densely to sparsely pilose or glabrous;

ligules less than 0.5 mm;

blades 8-30 cm long, 1-2 mm wide, usually flat, often curled at maturity.

cauline;

sheaths longer than the internodes, mostly glabrous, summit with hairs;

collars hispid, hairs 0.2-0.8 mm;

ligules less than 0.5 mm;

blades 20-55 cm long, 2-4 mm wide, light bluish-green, flat to loosely folded, glabrous abaxially, scabridulous adaxially.

paniculate, 10-30 cm long, (4)8-26 cm wide;

rachis nodes with straight hairs, hairs to 0.8 mm;

primary branches 6-16 cm, abruptly spreading to divaricate, stiff to lax, with axillary pulvini, usually not spikelet-bearing below midlength.

paniculate, 30-50 cm long, 15-25 cm wide;

rachis nodes glabrous or with straight hairs shorter than 0.5 mm;

primary branches 8-22 cm, ascending to divaricate or drooping, with axillary pulvini, basal portion without spikelets.

appressed, rarely spreading.

appressed along the branches.

1(3)-veined, brown or purple at maturity, acuminate;

lower glumes 6-13 mm;

upper glumes equaling or to 4 mm shorter than the lower glumes;

calluses 0.8-1.2 mm;

lemmas 10-15(17) mm, terminating in a strongly twisted, 2-4 mm awnlike beak, junction with the awns not conspicuous;

awns not disarticulating at maturity;

central awns 5-12 mm, markedly bent near the base;

lateral awns absent or to 1(3) mm, erect;

anthers 1.2-2.2 mm, brownish.

brown to purplish, 1-veined, with a 1-2 mm awn;

lower glumes 10-13 mm, slightly longer than the upper glumes;

calluses 0.5-1 mm;

lemmas 10-12(15) mm, glabrous, light gray to brownish, narrowing to a beak, beak less than 7 mm, not or only slightly twisted, junction with the awns not conspicuous;

awns unequal, not disarticulating at maturity;

central awns 20-25 mm, straight;

lateral awns 3-10 mm, to 1/2 as long as and about 1/2 as thick as the central awns, usually divergent;

anthers 3, about 3 mm, yellow-green.

6-8 mm.

about 8 mm.

= 22, 44.

= unknown.