Flora of North America species comparison

25-90 cm.

20-55 cm, erect or the bases decumbent, terete or weakly compressed;

nodes terete, 0-1 exserted.

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 1/3-2/3 their length, terete, sparsely to moderately scabrous, glabrous or retrorsely hispidulous, bases of basal sheaths glabrous, distal sheath lengths 2.7-6.5(9.7) times blade lengths;

collars of at least some leaves usually sparsely hispidulous;

ligules 1-2 mm, scabrous, truncate to obtuse;

innovation blades to 40 cm, adaxial surfaces moderately to densely scabrous or hispidulous on and between the veins;

cauline blades steeply reduced in length distally, 1-3 mm wide, involute, moderately thick, soft, abaxial surfaces smooth, margins scabrous, apices narrowly prow-shaped, flag leaf blades 1-4.5 cm long.

mainly pseudointravaginal.

extra- and intravaginal.

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.

4-8 cm, erect to nodding, lanceoloid to ovoid, loosely contracted, sparse, with 18-60 spikelets;

nodes with 1-2 branches;

branches 3-8 cm, ascending, lax, terete or weakly angled, moderately and sometimes coarsely scabrous, with 3-8 spikelets.

4-6.5 mm, laterally compressed;

florets 2-5;

rachilla internodes to 1 mm, smooth, glabrous.

6-9(11) mm, lengths to 3 times widths, laterally compressed, not sexually dimorphic;

florets 2-5(7);

rachilla internodes 1-2 mm, glabrous, scabrous, or sparsely to densely puberulent.

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.

subequal, distinctly keeled;

lower glumes 3-veined;

calluses diffusely webbed, hairs about 1/2 the lemma length;

lemmas 4-6(7) mm, lanceolate, distinctly keeled, glabrous, smooth or sparsely to moderately finely scabrous, keels scabrous, lateral veins moderately prominent, margins glabrous, apices acute;

palea keels scabrous, sometimes softly puberulent at midlength;

anthers vestigial (0.1-0.2 mm) or 2-3 mm.

= 28.

= 28.