Flora of North America species comparison

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

24-70 cm, not woody basally, erect, geniculate, or decumbent and rooting at the lower nodes, not branched from the aerial nodes;

nodes usually 2-3, glabrous or puberulent;

lower internodes glabrous.

mainly basal;

sheaths glabrous or sparsely hirsute;

ligules 0.1-0.4 mm, of hairs, often with marginal tufts of long hairs;

blades 2-12(19) cm long, 0.5-2.5 mm wide, flat to involute at maturity, hairs usually present basally.

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.

with 1-3(6) branches, these racemose on 2-8.5(12.5) cm rachises or digitate;

branches 13-50(75) mm, persistent, arcuate, scabrous, without papillose-based hairs, with 40-130 spikelets, terminating in a spikelet;

disarticulation above the glumes.

appressed.

pectinate, with 1 bisexual and 1 rudimentary floret.

mostly glabrous or scabrous, midveins sometimes with papillose-based hairs;

lower glumes 1.5-3.5 mm;

upper glumes 3.5-6 mm;

lowest lemmas 3.5-6 mm, pubescent at least basally, 5-lobed, central and lateral lobes veined and awned, awns 1-3 mm, central awns flanked by 2 membranous lobes;

lower paleas about 5 mm, shallowly bilobed, veins excurrent for less than 1 mm;

rachilla segments subtending second florets with a distal tuft of hairs;

anthers 1.7-2.9 mm, yellow or purple;

upper florets sterile, 0.9-3 mm, lobed almost to the base, lobes rounded, 3-awned, awns equal, 1-3 mm.

2.5-3 mm.

2.5-3 mm long, about 0.5 mm wide.

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, 28, 35, 40, 42, 60, 61, 77, 84.