Flora of North America species comparison

110-140 cm tall, 2.5-4 mm thick, internodes densely and retrorsely pubescent for 3-9 mm below the nodes, particularly the lower nodes, glabrous or retrorsely puberulent elsewhere;

nodes 3, pubescent or glabrate.

20-85 cm tall, 0.8-1.2 mm thick, usually retrorsely pubescent below the lower nodes, sometimes glabrous, sometimes pubescent over the whole of the internodes;

nodes 3-4.

21-25 cm long, (2)4-8 cm wide;

branches strongly divergent to ascending, straight, lower branches 5-7 cm.

6-25 cm long, 0.4-1.5 cm wide;

branches appressed, lower branches 2-7.5 cm.

appressed to the branches.

appressed to the branches.

subequal, 8-11.5 mm;

lower glumes 0.5-1 mm wide, 3-5-veined;

upper glumes 3-veined;

florets 5.5-7.5 mm long, 0.7-1 mm thick, fusiform, terete;

calluses 0.25-1.2 mm, acute;

lemmas evenly hairy, hairs at midlength and at the apices 0.5-1 mm, apical lobes 0.2-0.4 mm, membranous, flexible;

awns 20-50 mm, persistent, twice-geniculate, all segments scabrous to scabridulous, terminal segment straight;

paleas 2.6-3.8 mm, 1/2 - 3/4 as long as the lemmas, pubescent, hairs not extending beyond the apices, veins terminating below the apices, apices rounded;

anthers 2.5-4 mm, dehiscent, not penicillate.

subequal, 7-14 mm;

lower glumes 0.6-0.9 mm wide;

florets 5-6.5 mm long, 0.6-1 mm thick, fusiform, terete;

calluses 0.5-0.7 mm, sharp, dorsal boundary of the glabrous tip with the callus hairs rounded to acute;

lemmas evenly hairy, hairs 0.5-1 mm at midlength, apical hairs 0.8-2 mm, longer than those at midlength and those at the base of the awn, apical lobes membranous, about 0.2 mm;

awns 20-35 mm, persistent, twice-geniculate, first 2 segments pilose, with hairs 0.5-1.5 mm and of mixed lengths, terminal segment scabridulous to smooth;

paleas 2.8-4.2 mm, 1/2 - 3/4 as long as the lemmas, pubescent, distal hairs usually about 1 mm, extending well beyond the apices, apices rounded;

anthers about 2.5 mm, dehiscent, not penicillate.

3-5.5 mm, fusiform.

sheaths mostly glabrous or puberulent, margins ciliate distally;

collars glabrous or with hairs, hairs mostly to 0.5 mm, sides with tufts of 1.5-2 mm hairs;

ligules 0.4-2 mm, rounded to acute, abaxial surfaces hairy, hairs to 0.5 mm;

upper ligules 1-3 mm, similar in structure and pubescence;

blades 1-3.5 mm wide, abaxial surfaces smooth or scabrous, adaxial surfaces prominently ribbed, hairy, hairs 2-3 mm.

sheaths glabrous or pubescent, sometimes scabridulous, usually glabrous at the throat, becoming brown to gray-brown;

collars, including the sides, glabrous;

basal ligules 0.2-0.7 mm, truncate;

upper ligules 0.3-1 mm, often wider than the blades;

blades usually 10-25 cm long, 1-3 mm wide, usually involute, abaxial surfaces glabrous, adaxial surfaces more or less puberulent.

= unknown.

= 68.