Flora of North America species comparison

40-175 cm tall, 0.7-2.4 mm thick, lower cauline internodes usually glabrous, sometimes slightly pubescent below the lower nodes;

nodes 2-5.

30-50 cm tall, 1-1.3 mm thick, glabrous;

nodes 3-4.

glabrous;

collars puberulent, hairs about 0.2 mm, sometimes the margins with poorly developed tufts of hair to 0.5 mm;

ligules 1.8-5 mm, broadly to narrowly acute, glabrous;

blades 0.5-1.5 mm wide, flat or convolute, abaxial surfaces smooth, adaxial surfaces scabridulous.

9-36 cm long, 0.8-2 cm wide;

branches ascending to appressed, straight.

6-25 cm long, 7-15 cm wide;

branches ascending to strongly divergent, longest branches 5-8 cm;

pedicels appressed to the branches, paired, unequal, shorter pedicels in each pair usually less than 1/2 as long as the longer pedicels.

appressed to the branches.

confined to the distal 1/2 of the branches.

6-12.5 mm long, 0.7-1.1 mm wide;

lower glumes exceeding the upper glumes by 0.2-0.8 mm;

florets 4.5-7 mm long, 0.6-0.9 mm thick, fusiform;

calluses 0.2-1 mm, blunt to sharp, dorsal boundary of the glabrous tip with the callus hairs almost straight to acute;

lemmas evenly hairy, hairs at midlength 0.5-1 mm, hairs at the apices to 2 mm, erect to ascending, apical lobes 0.1-0.4 mm, membranous, flexible;

awns 19-45 mm, persistent, twice-geniculate, first 2 segments scabrous or with hairs shorter than 0.5 mm, terminal segment straight;

paleas 2-4 mm, 1/3 – 2/3 as long as the lemmas, pubescent, hairs usually not exceeding the apices, veins terminating before the apices, apices rounded;

anthers 2-3.5 mm, dehiscent, not penicillate.

saccate below, tapering at midlength, glabrous, midveins sometimes scabridulous, apices acuminate;

lower glumes 5.5-7 mm long, 0.9-1.5 mm wide;

upper glumes about 0.3 mm shorter;

florets 2.5-3.5 mm long, 0.7-1.5 mm thick, fusiform to obovoid;

calluses 0.3-0.5 mm, blunt;

lemmas densely pilose, hairs at midlength and on the apices similar, 1.2-2 mm, apical lobes 0.5-0.6 mm;

awns 6.5-9 mm, readily deciduous, scabrous;

paleas similar to the lemmas in length, texture, and pubescence, distal hairs exceeding the paleal apices, apices rounded, flat;

anthers about 1.5 mm, penicillate, dehiscent, well-filled.

3-4 mm, fusiform.

1.5-2.5 mm, globose to obovoid.

sheaths glabrous or sparsely to densely pubescent, margins sometimes ciliate;

collars glabrous or somewhat pubescent, without tufts of hair on the sides, collars of the flag leaves glabrous or sparsely pubescent;

basal ligules 0.2-0.7 mm, membranous, truncate to rounded, usually not ciliate;

upper ligules 1-1.5 mm, acute;

blades (0.5)1.2-5 mm wide.

= 36, 44.

= 48.