Flora of North America species comparison

(3)10-50(80) cm, often highly branched above the base.

30-120 cm, erect, unbranched.

cauline, glabrous;

sheaths shorter than the internodes, not disintegrating into threadlike fibers;

ligules 0.4-1 mm;

blades 2-14 cm long, 1-2.5 mm wide, flat to involute.

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.

panicles, 5-15(20) cm long, 0.5-3 cm wide, often interrupted below;

nodes glabrous or with straight, less than 0.5 mm hairs;

primary branches 1-4 cm, erect to ascending, without axillary pulvini, with 3-8 spikelets.

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.

crowded.

appressed, rarely spreading.

unequal, 1-veined, acuminate;

lower glumes 4-8 mm;

upper glumes 6-11 mm;

calluses 0.5-0.8 mm;

lemmas 6-9 mm, slightly keeled, midveins scabrous, junction with the awns not evident;

awns not disarticulating at maturity, flattened and straight to somewhat curved at the base, central rib flanked by equally wide pale wings;

central awns 7-15(20) mm;

lateral awns somewhat shorter, occasionally only 1-2 mm;

anthers 3, 0.3-0.7 mm.

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.

6-8 mm.

= 22.

= 22, 44.