Flora of North America species comparison

15-100 cm, slender to middling.

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

nodes terete, 1-2 exserted.

closed for 1/4 - 3/5 their length, terete, smooth or sparsely scabrous, margins not ciliate;

ligules 1.5-4(6) mm, smooth to sparsely scabrous, obtuse to acute;

blades 1-4 mm wide, flat, thin, lax, soft, apices narrowly prow-shaped.

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.

mostly extravaginal.

mainly extravaginal.

5-15 cm, lax, open, sparse;

nodes with 1-3(5) branches;

branches (2)3-8 cm, spreading to reflexed, capillary, usually angled, infrequently only sulcate or subterete, angles usually moderately densely scabrous, sometimes only sparsely so, with (3)4-15 spikelets.

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.

4-8 mm, lanceolate or narrowly lanceolate, green or partly purple to dark purple;

florets 2-5;

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.

subulate to lanceolate, thin, distinctly keeled, keels usually scabrous;

lower glumes subulate to narrowly lanceolate, 1-veined;

upper glumes distinctly shorter than to nearly equaling the lowest lemmas;

calluses sparsely webbed;

lemmas 3-4 mm, lanceolate, often partly purple, distinctly keeled, thin, smooth, or with sparse hooks apically, keels and marginal veins softly puberulent to long-villous, hairs extending 1/4 - 2/3 the keel length, sometimes sparse, lateral veins and intercostal regions glabrous, margins glabrous, infolded, apices sharply acute to acuminate, usually bronze-colored;

palea keels nearly smooth, scabrous, or pectinately ciliate;

anthers 0.2-1.1 mm.

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.

= 42.

= 56.