Flora of North America species comparison

5-160 cm, erect, not rooting at the lower nodes;

nodes glabrous.

60-140 cm, erect;

nodes glabrous.

densely pubescent, occasionally glabrous;

ligules 1-2.2 mm;

blades to 55 cm long, 2.2-8.3 mm wide, conduplicate (occasionally flat), glabrous below, pubescent above.

pubescent;

ligules 2-4 mm;

blades to 37 cm long, 2.2-11 mm wide, flat.

terminal, with 2-10 racemosely arranged branches;

branches 0.8-10.3 cm, divergent to spreading, often arcuate, terminating in a spikelet;

branch axes 0.8-2 mm wide, narrowly winged, glabrous, margins scabrous.

terminal, with 2-5 racemosely arranged branches;

branches 3.7-13 cm, divergent to erect;

branch axes 0.2-0.8 mm wide, glabrous, margins scabrous, terminating in a spikelet.

2.1-3.1 mm long, 2-2.8 mm wide, paired, imbricate, appressed to divergent from the branch axes, orbicular to suborbicular, stramineous.

3.1-4 mm long, 2-2.5 mm wide, paired, not imbricate, appressed to the branch axes, elliptic to obovate, yellow-brown.

1.9-2.1 mm, brown.

2.6-2.9 mm, purple.

glumes absent;

upper glumes and lower lemmas glabrous, 3-veined, margins entire;

upper florets white to light yellow.

glumes present or absent;

upper glumes glabrous or sparsely pubescent basally, (6)7-veined, margins entire;

lower lemmas glabrous or sparsely pubescent basally, lacking ribs over the veins, 5-veined, margins entire;

upper florets white.

= 20, 40.

= unknown.