Flora of North America species comparison

30-120 cm, erect, unbranched.

20-60(75) cm, 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.

basal and cauline;

sheaths usually longer than the internodes, glabrous except at the summit;

collars densely pilose, hairs 1-3 mm, cobwebby and tangled, often deflexed;

ligules less than 0.5 mm;

blades 4-28 cm long, less than 1 mm wide, usually involute, infrequently flat, usually arcuate, abaxial surfaces glabrous, adaxial surfaces glabrous or puberulent near the base, scabrous or puberulent distally.

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, 10-20 cm long, 3-10(12) cm wide;

rachis nodes usually glabrous, sometimes with straight, less than 0.3 mm hairs;

primary branches 2-11 cm, stiffly ascending to spreading, with axillary pulvini;

secondary branches and pedicels with or without pulvini;

terminal spikelets often divergent.

appressed, rarely spreading.

clustered on the distal 1/2 of 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.

equal or subequal, 1-veined, acuminate or awned, awns to 6 mm, brownish;

lower glumes 5-10 mm;

upper glumes 6-12 mm;

calluses 0.5-1 mm;

lemmas 7-13 mm, terminating in an obscure, narrow beak 1-4 mm long, 0.1-0.2 mm wide, junction with the base of the awns not evident;

awns 6-15 mm, not disarticulating at maturity, central and lateral awns similar in length and thickness, spreading to horizontal;

anthers 3, 1-3 mm, brown.

6-8 mm.

6-8 mm, tan.

= 22, 44.

= unknown.