Flora of North America species comparison

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

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

nodes terete, 1-2 exserted.

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 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.

intravaginal.

mainly extravaginal.

3-12 cm, ovoid;

nodes with 2-5 branches;

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

3-5 mm, laterally compressed, usually bulbiferous;

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

rachilla internodes 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.

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.

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.

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

= 56.