Flora of North America species comparison

35-95 cm, usually glabrous, sometimes pubescent below the nodes;

nodes 2-3, often dark, glabrous.

(30)40-100 cm, glabrous;

nodes 2-3, narrowed, yellowish to reddish.

glabrous, smooth;

ligules truncate to rounded, of basal leaves 0.4-1.8 mm, of upper leaves 1.5-2 mm;

blades 6-26 cm long, usually involute and 0.3-5 mm in diameter, sometimes flat and 0.5-1(1.5) mm wide, 3-veined, both surfaces glabrous, veins often scabridulous, margins scabrous.

glabrous;

ligules rounded, sometimes highest at the sides, entire, of basal leaves 0.4-3.3 mm, of upper leaves 1.8-2.5 mm;

blades 8-30 cm long, 0.6-3 mm wide, usually involute and about 0.5 mm in diameter, 3-veined, abaxial surfaces glabrous, smooth, adaxial surfaces scabrous over the veins, margins scabrous.

6.5-25 cm, open, often partially enclosed in the upper leaf sheath, with 20-60 spikelets;

branches flexuous;

pedicels 4-12 mm, flattened, hispid.

14-22 cm, open, with (10)15-25 spikelets;

branches lax, divergent, spikelets confined to the distal 1/2;

pedicels 15-50 mm, flattened, hispid.

subequal, 4-6.2 mm long, 1.8-3.1 mm wide, 5-7-veined, often partly purplish;

florets 3-5.5 mm long, 0.6-1.9 mm thick, somewhat laterally compressed, rectangular to slightly obovate in side view;

calluses 0.2-0.7 mm, blunt, strigose;

lemmas tan to light chocolate brown, shiny, smooth, evenly pubescent when immature, hairs easily rubbed off;

crowns about 0.8 mm wide, inconspicuous, glabrous or glabrate;

awns 11-20 mm, persistent, twice-geniculate;

paleas about 3.5 mm;

lodicules 2, about 1 mm;

anthers 0.3-0.5 mm, not penicillate.

subequal, 9-15 mm long, 0.9-1.9 mm wide, acute;

lower glumes 3(5)-veined;

upper glumes 5-veined;

florets 7-13 mm long, 1-1.2 mm thick, terete;

calluses 2-3 mm, sharp, strigose, hairs golden brown at maturity;

lemmas glabrous, tan to brown at maturity, smooth below, sharply tuberculate in the distal 1/3, constricted below the crown;

crowns 0.5-0.6 mm wide, straight, not revolute, hairy, hairs 0.2-0.5 mm, golden brown;

awns 40-75 mm, persistent, twice-geniculate, basal segment hispid, terminal segment scabrous;

paleas 7-14 mm;

anthers 0.3-0.5 mm or 3-4 mm, not penicillate.

2.5-3 mm long, about 0.6 mm thick, fusiform.

3.5-6 mm, terete.

& Giussani (2002) mistakenly cited Gould (1958) as having reported 2n = 28.

= 42.

= 22.