Flora of North America species comparison

14-120(180) cm tall, 0.3-2 mm thick, internodes glabrous or puberulent to densely pubescent;

nodes 2-4, glabrous or pubescent.

(10)15-40 (45) cm tall, 0.5-0.7 mm thick, glabrous;

nodes 1-2.

5-30 cm long, 0.5-1.5 cm wide;

branches appressed, straight, longest branches 1-7 cm.

(4)5-13(15) cm long, to 10 cm wide, lax;

branches divergent, flexuous, longest branches 2-10 cm, with spikelets confined to the distal portions, drooping.

appressed to the branches.

subequal, 9-15 mm long, 0.6-0.9 mm wide;

florets 5.5-7.5 mm long, 0.5-0.9 mm thick, fusiform, terete;

calluses 0.8-1.2 mm, sharp, dorsal boundary of the glabrous tip with the callus hairs narrowly acute;

lemmas evenly hair, hairs 0.5-1.5 mm at midlength, apical hairs somewhat longer than those below, sometimes similar in length to those at the base of the awns, sometimes longer, apical lobes 0.3-0.5 mm, membranous;

awns 15-55 mm, twice-geniculate, first 2 segments evidently hairy, terminal segment glabrous or partly to wholly pilose, sometimes scabrous;

paleas 2.2-3.5 mm, 2/5 – 3/5 as long as the lemmas, hairs at the tip usually shorter than 1 mm, frequently extending beyond the apices, apices rounded;

anthers 2.5-3.5 mm, dehiscent, not penicillate.

obtuse to acute;

lower glumes 3.5-7 mm long, 0.8-1.3 mm wide, 5(7)-veined;

upper glumes 3-6.5 mm, 3-veined;

florets 3-5.5 mm long, 1-1.5 mm thick, fusiform, terete;

calluses 0.1-0.2 mm, blunt;

lemmas coriaceous, shiny, glabrous, black to dark brown at maturity, margins overlapping at maturity, apices thickened dorsally;

awns 5-11 mm, readily deciduous, not or weakly geniculate, scabrous;

paleas 2.8-4.5 mm, similar to the lemmas in texture, glabrous;

anthers 1.6-1.8 mm, dehiscent, not penicillate.

4-6 mm, fusiform.

2-4 mm, ovoid.

sheaths glabrous or puberulent to densely pubescent, often ciliate at the throat;

collars often with tufts of hair at the sides;

ligules 0.2-1.5 mm, often ciliate;

blades 0.5-3 mm wide and flat, or convolute and 0.1-0.8 mm in diameter, lax to straight.

sheaths becoming flat with age, glabrous;

collars glabrous, including the sides;

basal ligules 0.8-1.3 mm, membranous, truncate to broadly acute, glabrous;

upper ligules to 1.6 mm;

blades tightly valvate to involute, 0.5-0.8 mm in diameter, abaxial surfaces scabridulous, adaxial surfaces hairy, sometimes densely hairy, hairs shorter than 0.05 mm.

=36.

= unknown.