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.

25-120 cm, decumbent to erect, sometimes trailing and rooting at the nodes, terete or weakly compressed;

nodes terete or slightly compressed, (0)1-3 exserted.

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 about 1/3-1/2 their length, compressed, usually densely scabrous, bases of basal sheaths glabrous, distal sheath lengths 0.5-4 times blade lengths;

collars smooth or scabrous, glabrous;

ligules 3-10 mm, scabrous, acute to acuminate;

blades 1-5 mm wide, flat, lax, soft, sparsely scabrous over the veins, margins scabrous, apices narrowly prow-shaped.

mostly intravaginal, some extravaginal.

intra-vaginal.

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.

8-25 cm, erect or lax, pyramidal, open, with 35-100+ spikelets;

nodes with 3-7 branches;

branches 2-8(10) cm, ascending to spreading, flexuous to fairly straight, angled, angles densely scabrous, crowded, with 5-35 spikelets in the distal 1/2-3/4.

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.

2.3-3.5 mm, lengths to 3 times widths, laterally compressed;

florets 2-4, bisexual;

rachilla internodes smooth or muriculate.

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.

distinctly keeled, keels scabrous;

lower glumes subulate to narrowly lanceolate, usually arched to sickle-shaped, 1-veined, distinctly shorter than the lowest lemmas;

calluses webbed, hairs over 2/3 the lemma length;

lemmas 2.3-3.5 mm, lanceolate, distinctly keeled, keels usually sparsely puberulent to 3/5 their length, marginal veins usually glabrous, infrequently the proximal 1/4 softly puberulent, intercostal regions smooth, glabrous, upper lemmas sometimes glabrous, lateral veins prominent, margins glabrous, apices acute;

palea keels smooth, muriculate, tuberculate, or minutely scabrous;

anthers 1.3-2 mm.

= 28.

= 14.