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.

50-100 cm tall, 0.8-1.5 mm thick, glabrous;

nodes 2-3.

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

branches ascending to appressed, straight.

20-55 cm long, 3-8 cm wide, open, often enclosed to midlength at anthesis;

lower branches 5-8 cm, ascending to divergent, flexuous.

appressed to 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.

5-12 mm long, 0.5-0.7 mm wide, 3-5-veined;

upper glumes 1-4 mm shorter, 3-veined;

florets 4-7.5 mm long, 0.5-0.9 mm thick, fusiform, terete;

calluses 1-2 mm, sharp;

lemmas evenly hairy, hairs 0.4-0.8 mm throughout, apical lobes not present;

awns 35-70 mm, persistent, twice-geniculate, first 2 segments scabrous, terminal segment flexuous;

paleas 1-2 mm, 1/3 – 1/2 as long as the lemmas, sparsely to moderately pubescent, apices rounded, flat;

anthers 3-3.5 mm, dehiscent, a few penicillate, hairs about 0.3 mm.

3-4 mm, fusiform.

about 4 mm, fusiform.

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.

sheaths mostly glabrous, ciliate on the margins;

collars glabrous on the back, usually with tufts of hair on the sides, hairs about 0.8 mm;

basal ligules 0.8-1.6 mm, membranous, glabrous, rounded to acute;

upper ligules to 4.5 mm, acute;

blades 0.7-3.5 mm wide, abaxial surfaces smooth to scabridulous, adaxial surfaces prominently ribbed, scabridulous or sparsely to densely pubescent, hairs about 0.1 mm.

= 36, 44.

= 44, 46.