Flora of North America species comparison

4-60 cm, outer culms of a tuft decumbent, sometimes geniculate, branched at the lower nodes.

20-60 cm, erect or somewhat geniculate at the base.

mostly basal;

sheaths pubescent, usually with tufts of long hairs on either side of the collar;

ligules 0.1-0.5 mm, of hairs;

blades 1-3 cm long, 1-2.5 mm wide, margins and usually both surfaces with papillose-based hairs.

2.5-10.5 cm, with (1)4-15 branches;

branches 5-45 mm, deciduous, densely pubescent (at least basally), with 2-10 spikelets per branch, axes extending 2-10 mm beyond the base of the terminal spikelets, apices entire;

disarticulation at the base of the branches, the break forming a sharp tip.

2.5-10 cm, with 4-8 branches;

branches 20-35 mm, persistent, with papillose-based hairs, with 40-65 spikelets, branches terminating in a spikelet;

disarticulation above the glumes.

appressed.

pectinate, with 1 bisexual floret and 2 rudimentary florets.

unequal;

lower glumes about 2 mm, glabrous or sparsely pubescent at the base, mucronate;

upper glumes 3-4 mm, keels with papillose-based hairs, apices bilobed, awned from between the teeth, awns to 0.7 mm;

lowest lemmas 3-4 mm, pilose or villous proximally, 3-awned, awns 2-3 mm, central awns flanked by 2 membranous lobes;

lowest paleas about 2.5 mm, 4-lobed, 2-awned;

anthers 1.8-2 mm, yellow;

rachilla segments subtending second florets with densely pubescent apices;

second florets lobed nearly to the base, lobes ovate, awns 2-4 mm, exceeding those of the lowest lemmas, third florets minute scales, glabrous, unawned or with a single awn.

2.5-3 mm.

1.3-1.5 mm.

0.2-0.5 mm, membranous, lacerate or ciliate;

blades 2-5(9) cm long, 0.7-2 mm wide, flat or folded, adaxial surfaces sometimes with papillose-based hairs, margins usually with papillose-based hairs near the ligules.

spikelet on each branch with 1 floret;

lower glumes 1.5-3.5 mm, glabrous, narrow to subulate;

upper glumes 5.5-6.2 mm, densely pubescent, at least on the basal 1/2;

lemmas 5.8-6 mm, acuminate, unawned;

lowest paleas almost as long as the lemmas, bifid, glabrous;

rachillas prolonged beyond the florets for about 0.5 mm.

spikelets with 1 bisexual and 1 rudimentary floret, glumes unequal, glabrous, minutely scabrous on the keels; narrowly acute or acuminate;

lower glumes 1.5-2 mm;

upper glumes 5-6 mm, glabrous or sparsely pubescent basally, often divergent;

lowest lemmas 6-8 mm, veins pubescent, lateral veins excurrent as short (to 1 mm) awns, acuminate, midvein extended into a setaceous tip or a short awn;

lowest paleas 5-7 mm, bifid, veins often excurrent as short awns;

anthers about 2.5 mm, yellow or yellow and red;

distal florets reduced to a pubescent, 3-awned, awn column, awns 2-7 mm, exserted.

= 40.

= 20.