Flora of North America species comparison

to 100 cm.

to 150 cm.

glabrous or sparsely hirsute;

ligules to 3 mm;

blades to 20 cm long, 5-10 mm wide, scabrous.

glabrous or sparsely hirsute;

ligules to 3 mm;

blades to 30 cm long, to 10 mm wide, scabrous or sparsely hirsute.

with 6-20 branches in several closely-spaced whorls, appearing as a single terminal cluster;

branches to 15 cm, erect, with 7-9 spikelets per cm.

with 7-20 branches in a few, evidently separate whorls;

branches to 20 cm, ascending, with 7-9 spikelets per cm.

with 1 bisexual and 1(2) sterile floret(s).

with 1-2 bisexual florets, a third floret with a rudimentary pistil and stamens sometimes present below the (1)2-3 sterile florets.

0.8-1.1 mm;

upper glumes 2-2.5 mm, awned, awns to 2 mm;

lowest lemmas 2.4-3.8 mm long, about 0.5 mm wide, dorsally compressed, narrowly lanceolate to elliptic, scabrous, particularly distally, apices bilobed and 3-awned, central awns 8-12 mm, equaling or slightly longer than the 5-12 mm lateral awns;

first sterile florets 1-1.5 mm, narrowing to 3 subequal 5-7 mm awns;

second sterile florets, if present, similar but smaller.

2-3 mm;

upper glumes 3-5 mm;

lowest lemmas 3-5 mm, mostly glabrous, margins short-ciliate near the middle, sparsely scabrous distally, apices 3-awned, central awns 8-12 mm, lateral awns 0.5-1.5 mm;

lowest sterile florets 1.5-3 mm long, about 0.3 mm wide, mostly glabrous, margins sometimes short-ciliate near the middle, apices 3-awned, central awns to 8 mm, lateral awns 0.2-1 mm.

1.7-2.3 mm, strongly dorsally flattened.

1.8-2.2 mm, strongly dorsally compressed.

= 40.

= 80.