Flora of North America species comparison

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

nodes terete, usually 1-3 exserted.

10-30(40) cm, mostly erect, with 0-1 slightly exposed nodes.

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.

closed for 1/5 – 2/5 their length, terete, smooth and glabrous, bases of basal sheaths glabrous, distal sheath lengths 1.4-3.6 times blade lengths;

collars smooth, glabrous;

ligules of cauline leaves 3-8 mm, colorless, transparent, smooth, margins decurrent, apices obtuse to acuminate, ligules of the innovation leaves 2.5-6 mm;

innovation blades similar to the cauline blades, 1-2 mm wide, involute, moderately thick, abaxial surfaces smooth, adaxial surfaces smooth or sparsely scabrous, sometimes sparsely hispidulous;

cauline blades gradually reduced in length distally, 1-2 mm wide, folded or involute, moderately thick, soft, abaxial surfaces smooth, apices narrowly prow-shaped.

both intra- and extravaginal.

strictly 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.

3-7 cm, erect or slightly nodding, narrowly lanceoloid to narrowly ovoid, often interrupted, contracted to loosely contracted, with 9-38(60) spikelets;

nodes with 1-2 branches;

branches 0.5-1.5(2.5) cm, erect at maturity, slender, terete to sulcate or weakly angled, sparsely to moderately scabrous, with 1-5 spikelets.

(3)4-7 mm, laterally compressed;

florets 2-3(4);

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

4-6.5 mm, lengths to 3.5 times widths, lanceolate, laterally compressed, not sexually dimorphic, usually strongly anthocyanic, less so in pistillate plants;

florets 2-4;

rachilla internodes smooth, glabrous or sparsely hispidulous.

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, lanceolate, thin, lustrous, distinctly keeled, keels and distal surface smooth or sparsely finely scabrous;

lower glumes 3-veined, distinctly shorter than the lowest lemmas;

calluses glabrous;

lemmas 3.5-5.5 mm, lanceolate, distinctly keeled, thinly membranous, smooth or sparsely scabrous, glabrous, lateral veins moderately prominent, margins glabrous, apices acute;

palea keels finely scabrous;

anthers vestigial (0.1-0.2 mm) or 2-4.5 mm.

= 28.

= 42, 81 (both counts of uncertain application).