Flora of North America species comparison

15-60 cm, erect or spreading, bases bulbous.

30-100 cm, erect, terete, with 0(1) exserted nodes.

closed for about 1/4 their length, terete, lowest sheaths with swollen bases;

ligules 1-3 mm, smooth or scabrous, apices obtuse to acute;

blades 1-2.5 mm wide, flat, thin, lax, soon withering.

closed for 1/10(1/8) their length, terete, bases of basal sheaths glabrous, distal sheath lengths 1.5-5 times blade lengths;

ligules 4-6 mm, scabrous, obtuse to acute;

innovation blades similar to the cauline blades;

cauline blades 1-3 mm wide, folded to involute, thick, fairly firm, pale green, abaxial surfaces scabrous, apices narrowly prow-shaped.

intravaginal.

intravaginal.

3-12 cm, ovoid;

nodes with 2-5 branches;

branches ascending to spreading, terete, usually smooth or sparsely scabrous, infrequently moderately scabrous.

5-18(21) cm, erect, narrowly to broadly lanceoloid, loosely contracted, congested, with 40-100+ spikelets;

nodes with 2-3(5) branches;

branches 3-10 cm, erect to ascending, straight, angles densely scabrous, with 5-27 spikelets in the distal 1/2.

3-5 mm, laterally compressed, usually bulbiferous;

florets 3-7, the basal floret, and sometimes additional florets, normal;

rachilla internodes smooth, glabrous.

(4)4.5-7 mm, lengths 3-3.5 times widths, lanceolate, laterally compressed, drab;

florets 3-5;

rachilla internodes usually shorter than 1 mm, smooth.

keeled, keels scabrous;

lower glumes 3-veined;

upper glumes shorter than or subequal to the lowest lemmas;

calluses webbed or glabrous;

lemmas 3-4 mm, lanceolate, keeled, glabrous or the keels and marginal veins short- to long-villous, intercostal regions glabrous or softly puberulent, apices acute;

paleas scabrous, keels often softly puberulent at midlength;

anthers 1.2-1.5 mm and functional, sometimes aborted late in development, sometimes not developed.

lanceolate, slightly unequal, pale, distinctly keeled, keels sparsely scabrous;

lower glumes 3-veined;

calluses glabrous, rarely with a crown of hairs, hairs to 0.1 mm;

lemmas 3-4 mm, lanceolate, distinctly keeled, finely scabrous, usually glabrous, keels and marginal veins rarely sparsely puberulent proximally, lateral veins obscure to moderately prominent, intercostal regions muriculate, margins glabrous, apices acute;

paleas scabrous over the keels;

anthers 1.2-1.8 mm.

= 14, 21, 28, 39, 42, 45.

= 42.