Flora of North America species comparison

10-60 cm.

(2)5-60(70) cm tall, 0.3-1 mm thick, usually erect, bases rarely geniculate;

nodes terete, usually 1 exserted.

closed for 1/3 – 2/3 their length, terete, smooth;

ligules 1.5-3.5 mm, smooth or sparsely scabrous;

blades 1.5-4 mm wide, flat, thin, soft, apices broadly prow-shaped.

closed for 1/4 - 1/2 their length, usually compressed and keeled, smooth or the keels scabrous;

ligules 2-6 mm, smooth or scabrous, usually decurrent, obtuse to acute;

blades 1.5-5 mm wide, flat, thin, soft, finely scabrous, apices broadly prow-shaped, cauline blades (1)4-15 cm, flag leaf blades usually 1-4 cm.

mixed intra- and extravaginal.

intravaginal.

4-15 cm, nodding, open, with numerous spikelets and 1-2 branches per node;

branches (2)3-7 cm, spreading to reflexed, lower branches usually reflexed, flexuous, usually terete, smooth or sparsely scabrous, with (3)6-18 spikelets.

(1)5-15 cm, erect, cylindrical, contracted, sometimes interrupted, congested, with 2-3(5) branches per node;

branches erect or steeply ascending, smooth or sparsely to densely scabrous.

4-6 mm, lanceolate to broadly lanceolate, usually partly to wholly purplish, with 3-5 florets;

rachilla internodes shorter than 1 mm, smooth.

4-7 mm, laterally compressed;

florets 3-7;

rachilla internodes to 1 mm, smooth, glabrous.

narrowly to broadly lanceolate, distinctly keeled, keels smooth or nearly so;

lower glumes 1-veined;

upper glumes shorter than or subequal to the lowest lemmas;

calluses webbed;

lemmas 2-3.5 mm, lanceolate, partly purple to fairly strongly purple, distinctly keeled, keels and marginal veins short- to long-villous, keels hairy for 2h-ls their length, lateral veins usually sparsely softly puberulent at least on 1 side, lateral veins obscure to moderately prominent, intercostal regions smooth, minutely bumpy, glabrous, apices acute, slightly bronze-colored or not;

palea keels scabrous, usually softly puberulent at midlength;

anthers 0.6-1 mm.

subequal, distinctly keeled, keels and sometimes the lateral veins scabrous;

lower glumes 1(3)-veined;

upper glumes shorter than or subequal to the lowest lemmas;

calluses webbed;

lemmas 2.6-4.2 mm, lanceolate, distinctly keeled, smooth, keels, marginal veins, and sometimes the lateral veins short- to long-villous, keels hairy to near the apices, marginal veins to 2/3 their length, lateral veins obscure to moderately prominent, intercostal regions glabrous or softly puberulent, upper margins white, apices acute;

palea keels softly puberulent to short-villous at midlength, scabrous near the apices, intercostal regions usually softly puberulent;

anthers 1-3, 0.2-1 mm.

= 28.

= 28, 28+1.