Flora of North America species comparison

20-60(70) cm, erect or geniculate at the base;

nodes terete, usually 1-3 exserted.

2-120 cm, terete or somewhat compressed;

nodes terete or weakly compressed.

closed for 1/2-1/4 their length, usually compressed and keeled, usually smooth, infrequently scabrous;

ligules 2.5-7 mm, smooth or scabrous, usually decurrent, obtuse to acute;

blades 1.5-5 mm wide, usually flat, rarely folded, lax, soft, smooth or sparsely scabrous, margins scabrous, apices broadly prow-shaped, cauline blades 3-15 cm, flag leaf blades 1-4 cm.

usually closed for 1/2-7/8 their length, sometimes only 1/20 – 1/10 their length, terete to distinctly compressed, smooth or scabrous;

ligules 0.7-12 mm, milky white, smooth or scabrous, truncate to acuminate;

innovation shoot blades similar to the cauline blades;

cauline blades 0.6-15 mm wide, flat or folded, thin or moderately thick, lax or moderately straight, abaxial surfaces usually smooth, sometimes scabrous over the midvein, adaxial surfaces smooth or scabrous over the veins, margins scabrous, apices narrowly to broadly prow-shaped.

both intra- and extravaginal.

both intra-and extravaginal or mainly extravaginal.

(5)10-15(25) cm long, 1/4-1/2 the plant height, usually erect, infrequently slightly nodding, usually eventually open, sometimes interrupted, sparse, with 1-3(5) branches per node;

branches initially erect and straight, usually some eventually spreading or reflexed, smooth or sparsely to moderately scabrous.

(1)2-40 cm, erect or nodding to lax, contracted or open, sparse or congested, with 1-7 branches per node;

branches erect to reflexed, terete or angled, angles smooth or scabrous, smooth or sparsely scabrous between angles.

(3)4-7 mm, laterally compressed;

florets 2-3(4);

rachilla internodes usually 1-1.2+ mm, smooth or sparsely scabrous, glabrous.

(2)2.4-9 mm, laterally compressed, rarely bulbiferous;

florets (1)2-7, usually normal, sometimes the anthers aborting, rarely bulb-forming.

unequal, distinctly shorter than the adjacent lemmas, distinctly keeled, keels smooth or sparsely scabrous;

lower glumes 1-3-veined, 1/2 - 2/3 the length of the upper glume, 1/2 - 2/3 the length of the lowest lemmas;

upper glumes shorter than or subequal to the lowest lemmas;

calluses of some or all florets sparsely webbed;

lemmas 2.5-4 mm, lanceolate to narrowly lanceolate, distinctly keeled, smooth or scabrous throughout, glabrous, lateral veins obscure to moderately prominent, apices narrowly acute, usually anthocyanic near the tip;

palea keels sparsely scabrous;

anthers 3, 0.5-1(1.8) mm.

unequal to subequal, distinctly shorter than the adjacent lemmas, usually bisexual, distinctly keeled;

lower glumes 1-3-veined;

calluses terete or slightly laterally compressed, usually dorsally webbed, sometimes glabrous;

lemmas 2-6 mm, narrowly to broadly lanceolate, distinctly keeled, glabrous or hairy, lateral veins obscure to prominent, margins milky white, apices obtuse to narrowly acute;

palea keels scabrous, glabrous or hairy at midlength;

anthers (1, 2) 3, usually 0.1-1.1(1.8) mm, sometimes 1.5-3 mm and then sometimes aborting late in development.

= 28.