Flora of North America species comparison

25-90 cm.

50-120 cm, stout.

closed for 1/2 - 3/4 their length, smooth or sparsely scabrous, margins not ciliate;

ligules 0.3-2.1 mm, smooth or sparsely scabrous, truncate to obtuse, ciliolate;

blades 0.6-3.5 mm wide, flat.

closed for 1/2 - 3/4 their length, distinctly compressed, keels winged, bases of basal sheaths glabrous;

ligules 1-2 mm, smooth or sparsely scabrous, apices truncate;

blades (4)6-15 mm wide, flat or folded, apices broadly and abruptly prow-shaped.

mainly pseudointravaginal.

extravaginal.

7.5-15(18) cm, lax, pyramidal, open, sparse;

nodes with 1-3(5) branches;

branches 3-8 cm, ascending, straight to spreading, angled, angles prominent, scabrous.

10-20 cm, ovoid to pyramidal, open, spikelets numerous, with 3-5 branches per node;

branches ascending to spreading, angled, angles densely scabrous.

4-6.5 mm, laterally compressed;

florets 2-5;

rachilla internodes to 1 mm, smooth, glabrous.

4-9 mm, laterally compressed;

florets 3-5;

rachilla internodes about 1 mm, scabrous, glabrous.

1/2-1/3 the length of the adjacent lemmas, distinctly keeled, keels scabrous;

lower glumes subulate to narrowly lanceolate, (1)3-veined;

upper glumes shorter than or subequal to the lowest lemmas;

calluses webbed;

lemmas (2.5)3.2-4.7 mm, lanceolate, green, distinctly keeled, keels and marginal veins long-villous, hairs extending up almost the whole keel length, lateral veins prominent, intercostal regions smooth, minutely bumpy, usually glabrous, rarely sparsely softly puberulent, apices acute, blunt, or pointed, white, not bronze;

palea keels softly puberulent at midlength, apices scabrous;

anthers (0.5)0.8-1.2(1.5) mm.

distinctly keeled, keels scabrous;

lower glumes 1-3-veined;

calluses glabrous;

lemmas 3.5-4.5 mm, narrowly lanceolate, distinctly keeled, scabrous, glabrous throughout, lateral veins prominent, apices acute;

palea keels scabrous, glabrous;

anthers 1.5-3 mm.

= 28.

= 14.