Flora of North America species comparison

(7)15-60 cm tall, 1.5-2 mm thick, bases decumbent, terete or weakly compressed, smooth or moderately scabrous below the panicles;

nodes terete, 0(1) exserted.

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

closed for about 1/2 their length, terete, glabrous or sparsely retrorsely scabrous, bases of basal sheaths glabrous, distal sheath lengths 1.7-4(6) times blade lengths;

collars smooth, glabrous;

ligules 1-5 mm, scabrous, truncate to acute, ciliolate;

innovation blades to 30 cm, moderately to densely scabrous or hispidulous on and between the veins;

cauline blades subequal in length, 2-4 mm wide, involute, thick, somewhat arcuate, firm, abaxial surfaces smooth or moderately to densely scabrous or hispidulous on and between the veins, apices narrowly prow-shaped, flag leaf blades 1-10 cm.

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.

mostly intravaginal, some extravaginal.

intravaginal.

3-15 cm, erect, ovoid to lanceolate, contracted, often interrupted, congested, with 15-80 spikelets, rachises glabrous, smooth to moderately scabrous;

nodes with 1-2 branches;

branches 1-6 cm, erect, stiff, terete to weakly angled, smooth or sparsely to moderately scabrous, with 3-17 spikelets.

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.

9-17 mm, lengths to 3 times widths, laterally compressed, not sexually dimorphic;

florets 3-6(10);

rachilla internodes smooth, usually hairy, hairs 0.3-0.4+ mm, rarely 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.

broadly lanceolate, subequal to the adjacent lemmas, distinctly keeled, keels sparsely scabrous near the apices;

lower glumes 3-veined;

upper glumes usually 7+ mm, 3-5-veined;

calluses usually with a crown of hairs, sometimes glabrous or diffusely webbed;

lemmas (6)7.5-11 mm, lanceolate, 5-7(11)-veined, distinctly keeled, keels and marginal veins, and sometimes the lateral veins, short-villous to softly puberulent, intercostal regions smooth or scabrous, glabrous or softly puberulent, margins glabrous, apices acute;

palea keels scabrous, intercostal regions glabrous;

anthers vestigial (0.1-0.2 mm) or (2)3-4(5) mm.

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.

= 28.

= 42.