Flora of North America species comparison

15-95 cm, erect or decumbent and rooting at the lower nodes.

15-60 cm, erect.

glabrous;

ligules 0.3-0.5 mm, erose to lacerate;

blades to 15 cm long, 0.3-0.6 mm wide, with basal hairs, otherwise usually glabrous.

glabrous;

ligules 0.7-1 mm;

blades to 20 cm long, 2-4 mm wide, without basal hairs, glabrous or scabrous, upper cauline leaves often greatly reduced.

digitate, with 7-15 evidently distinct branches;

branches 3-8 cm, more or less erect, averaging 14 spikelets per cm.

with 10-20 branches in several closely-spaced whorls;

branches 2-5 cm, spreading, with 14-18 spikelets per cm;

disarticulation beneath the glumes.

with 1 bisexual and 2(3) sterile florets.

with 1 bisexual and 1 sterile floret.

1.2-2.1 mm;

upper glumes 2.3-2.7 mm;

lowest lemmas 2-2.7 mm, ovate to elliptic, calluses and distal portion of the margins pilose, hairs to 1 mm, keels glabrous or pilose, apices awned, awns 4-7.7 mm;

second florets 0.9-1.3 mm long, 0.4-0.9 mm wide, slightly to strongly widened distally, inflated, usually glabrous, truncate, awned, awns 5-7 mm;

third florets obovoid to subspherical, smaller than the first, strongly inflated.

0.5-0.7 mm;

upper glumes 1-1.5 mm;

lowest lemmas 1.5-2 mm long, 0.7-1 mm wide, broadly elliptic, mostly glabrous but the keels and marginal veins appressed-pilose, obtuse, awned, awns 0.3-1.5 mm;

second florets 1-1.5 mm long and about equally wide, conspicuously inflated, spherical, with the distal portion of the margins inrolled, not or inconspicuously bilobed, lobes less than 1/5 as long as the lemmas, midveins sometimes excurrent to 1.5 mm.

1.1-1.4 mm.

0.9-1.2 mm long, about 0.5 mm wide, obovoid.

= 20, 40, ca. 50.

= 40.