Flora of North America species comparison

15-80 cm, erect or the bases decumbent, terete or weakly compressed;

nodes terete, 0-1 exserted.

(15)20-40 cm, erect or decumbent, with 1-2 exserted nodes.

closed for 1/10 – 1/5(1/4) their length, terete, smooth or sparsely scabrous, glabrous, bases of basal sheaths glabrous, distal sheath lengths (1.2)1.5-9(20) times blade lengths;

ligules (1)1.5-4(5) mm, smooth or sparsely to moderately scabrous, apices obtuse to acute;

blades strongly to gradually reduced in length distally, 1.5-5 mm wide, flat and moderately thin to folded and moderately thick and firm, abaxial surfaces smooth, adaxial surfaces smooth or sparsely to moderately scabrous, primarily over the veins, apices narrowly prow-shaped, flag leaf blades (0.4)1-7(10) cm.

closed for 1/5-1/3 their length, terete, smooth, bases of basal sheaths glabrous, distal sheath lengths 4-33 times blade lengths, smooth, glabrous;

ligules (1.5)2-5 mm, smooth or sparsely scabrous, margins distinctly decurrent, apices obtuse to acute, ligules of innovations prominent, milky white;

innovation blades similar to the cauline blades;

cauline blades gradually reduced in length upwards, (1)1.5-3 mm wide, flat, thick, fairly firm, smooth or sparsely scabrous, margins white, apices broadly prow-shaped, flag leaf blades 0.2-1.8 cm, infrequently absent.

intra- and extravaginal.

mainly intravaginal.

(2.5)4-12(18) cm, erect, usually narrowly lanceoloid, contracted, sometimes interrupted, infrequently loosely contracted, usually congested, with 25-100 spikelets;

nodes with 1-5 branches;

branches 1-9 cm, erect to infrequently ascending, rarely spreading, terete to weakly angled, smooth or the angles sparsely to moderately scabrous, with 3-24 spikelets.

4-8 cm, erect, linear to narrowly lanceoloid, contracted, moderately congested, with 9-35 spikelets;

nodes with 1-2 branches;

branches 1-2.5 cm, erect to steeply ascending, straight, sulcate or angled, angles sparsely to moderately scabrous, with 1-4 spikelets in the distal 1/2.

3.2-7 mm, lengths to 3.5(3.8) times widths, laterally compressed;

florets 2-7;

rachilla internodes smooth, sometimes sparsely puberulent.

7-9 mm, lengths 3.5-4 times widths, lanceolate, fairly compressed, pale, slightly lustrous;

florets (2)3-4;

rachilla internodes 1-2 mm.

lanceolate, distinctly keeled, smooth or sparsely scabrous;

lower glumes 3-veined;

calluses usually glabrous, infrequently webbed, hairs to 1/4 the lemma length;

lemmas 2.5-4.5 mm, lanceolate to narrowly lanceolate, distinctly to weakly keeled, keels and marginal veins short- to long-villous, lateral veins moderately prominent, glabrous or puberulent, intercostal regions usually glabrous, infrequently hairy, hairs to 0.3 mm, margins glabrous, apices acute or blunt;

palea keels scabrous, glabrous or short-villous at midlength, intercostal regions usually glabrous, sometimes puberulent to short-villous;

anthers 1.3-2.2 mm.

lanceolate to broadly lanceolate, margins broadly scarious, keels indistinct, smooth or sparsely scabrous;

lower glumes 3-veined, slightly to distinctly shorter than the lowest lemma;

calluses glabrous;

lemmas 4.5-6 mm, lanceolate, somewhat weakly keeled, glabrous or the keels, marginal veins, and intercostal regions very sparsely puberulent over the proximal 1/3, lateral veins obscure, margins strongly inrolled proximally, broadly scarious distally, glabrous, apices acute;

palea keels scabrous, glabrous or puberulent at midlength;

anthers 2.2-3.5 mm.

= 56, 56+1, 56-58, 63, 64, 70, 76, 84, ca. 90, 95+-5, 100, 103.

= 42.