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.

30-75 cm tall, 0.5-1.7 mm thick, internodes pubescent or glabrous, pubescence more common on the lower internodes, particularly just below the nodes;

nodes 2-3, lower nodes retrorsely pubescent, upper nodes glabrous or pubescent.

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

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

7-15 cm long, 0.5-2.5 cm wide, often included in the upper leaf sheaths at the start of anthesis;

branches 1.5-6 cm, appressed to strongly ascending, with 1-6 spikelets.

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.

often purplish;

lower glumes 10-15 mm long, 1.2-2 mm wide;

upper glumes to 2 mm shorter;

florets 6-9 mm long, 0.7-1.2 mm thick, fusiform, terete;

calluses 0.9-1.5 mm, sharp;

lemmas coriaceous, evenly pubescent or the back glabrate distally, hairs 0.5-0.8 mm, apices lobed on 1 margin, lobe about 0.1 mm long, thick, apical lemma hairs 0.5-0.8 mm;

awns 32-56 mm, twice-geniculate, first 2 segments pilose, hairs 0.8-2 mm, terminal segment glabrous, often scabrous;

paleas 4.6-6.1 mm, 3/4 - 9/10 as long as the lemmas, sparsely pubescent towards the base;

anthers 2.5-3.5 mm, dehiscent, not penicillate.

5-7 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, usually smooth, brown or gray-brown;

collars glabrous, without tufts of hair at the sides;

basal ligules 1.5-6 mm, hyaline, rounded to acute, lacerate;

upper ligules to 8 mm, hyaline, acute, glabrous;

blades 0.5-2 mm wide, convolute, abaxial surfaces scabrous, adaxial surfaces scabrous or hairy, hairs about 0.3 mm.

= unknown.

=34.