Flora of North America species comparison

1-12 cm, slender.

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

nodes terete, usually 1-3 exserted.

closed for 1/6 – 1/4 their length, terete;

ligules 1-3 mm, milky white to hyaline, smooth;

blades 0.5-2 mm wide, flat or folded, or slightly inrolled, thin, without papillae (at 100x), apices narrowly prow-shaped.

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.

all or mainly intra-vaginal.

both intra- and extravaginal.

1-3 cm, erect, contracted, usually exserted from the sheaths;

branches to 1.5 cm, erect to steeply ascending, slender, sulcate or angled, smooth or the angles sparsely scabrous;

pedicels shorter than the spikelets.

(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.

3-4 mm, laterally compressed, green or anthocyanic;

florets 2-3;

rachilla internodes shorter than 1 mm, smooth.

(3)4-7 mm, laterally compressed;

florets 2-3(4);

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

usually equaling or exceeding the lowest lemmas, sometimes also equaling or exceeding the upper florets, lanceolate to broadly lanceolate, distinctly keeled, keels smooth;

lower glumes 3-veined;

calluses glabrous;

lemmas 2.5-3 mm, lanceolate, distinctly keeled, thin, usually glabrous, keels and marginal veins rarely sparsely puberulent proximally, apices acute;

palea keels scabrous;

anthers 0.2-0.8 mm.

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.

= 14.

= 28.