Flora of North America species comparison

25-90 cm.

28-85 cm, erect or the bases decumbent, terete or weakly compressed;

nodes terete, 1-2 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 about 1/15 – 1/5 their length, sometimes fused for a longer distance by a narrow hyaline membrane, terete, bases of basal sheaths glabrous, distal sheath lengths 0.8-1.5 times blade lengths;

ligules 0.5-3 mm, scabrous, usually lacerate;

blades scarcely reduced in length distally, 2-5 mm wide, flat, lax, apices narrowly prow-shaped, flag leaf blades 5-15 cm long.

mainly pseudointravaginal.

mainly 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, erect, pyramidal, open, sparse, with 25-70 spikelets;

nodes with 1-3(5) branches;

branches 5-15 cm, ascending, straight, spreading to eventually reflexed, angled, angles mostly moderately to densely scabrous, with 5-15 spikelets.

4-6.5 mm, laterally compressed;

florets 2-5;

rachilla internodes to 1 mm, smooth, glabrous.

4.5-6 mm, lengths 3.5 times widths, laterally compressed;

florets 2-3;

rachilla internodes, at least some, longer than 1 mm, smooth, 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;

lower glumes 1-3-veined;

upper glumes shorter than or subequal to the lowest lemmas;

calluses webbed, hairs over 1/2 the lemma length;

lemmas 3.5-5 mm, narrowly lanceolate, distinctly keeled, smooth, glabrous throughout, lateral veins moderately prominent, apices acute to acuminate;

paleas smooth to scabrous over the keels;

anthers about 2 mm.

= 28.

= 56.