Flora of North America species comparison

100-230 cm tall, 2-4.5 mm thick, mostly glabrous, often pubescent below the nodes, the pubescence antrorse or retrorse;

nodes 4-5.

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.

15-30 cm long, 0.8-3.5 cm wide;

branches straight, appressed to ascending, lower branches 3-9 cm.

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

branches ascending to appressed, straight.

appressed to the branches.

appressed to the branches.

subequal, 9-11.5 mm long, 1-1.4 mm wide;

florets 5.9-8.5 mm long, 0.9-1.2 mm thick, fusiform, terete;

calluses 0.3-1 mm, blunt;

lemmas evenly hairy, hairs at midlength 0.3-0.8 mm, apical hairs to 1.5 mm;

awns 20-32 mm, persistent, twice-geniculate, scabridulous to scabrous, scabrules to about 0.1 mm, longest on the middle segment, terminal segment straight;

paleas 3.7-5.6 mm, 2/3 - 3/4 as long as the lemmas, hairy, hairs about 0.5 mm, not exceeding the apices, veins terminating below the apices, apices rounded;

anthers 4-5 mm, dehiscent, penicillate.

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.

5-6 mm.

3-4 mm, fusiform.

sheaths mostly glabrous, margins usually ciliate distaily;

collars hairy, those of the flag leaves densely hairy, hairs 0.5-2 mm, sides glabrous;

basal ligules 1-2 mm;

upper ligules to 4 mm, truncate, rounded, or obtuse, glabrous;

blades 6-10 mm wide, glabrous, abaxial surfaces smooth, adaxial surfaces prominently ribbed, ribs scabrous.

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.

= 64.

= 36, 44.