Flora of North America species comparison

30-120 cm, erect, unbranched.

45-80 cm, erect, usually 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 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 5-15 cm long, about 0.5 mm wide, usually involute, occasionally loosely folded, glabrous, light green.

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, 12-20 cm long, 2-8 cm wide;

primary branches 2-5 cm, erect to horizontal, with or without axillary pulvini, with 1-5 spikelets.

appressed, rarely spreading.

appressed or with axillary pulvini and spreading.

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.

6-10(12) mm, equal or the lower glumes slightly shorter, 1-veined, brownish;

calluses about 0.5 mm;

lemmas (6)7-14(16) mm, mostly smooth, mottled, terminating in a 2-4 mm, usually twisted, scabrous beak;

central awns 5-10 mm, sharply curved at the base, spreading distally;

lateral awns absent or to 3 mm, erect;

anthers 3, about 1.5 mm, brown.

6-8 mm.

5-8 mm.

= 22, 44.

= unknown.