Flora of North America species comparison

30-130 cm, decumbent;

nodes glabrous or pubescent.

65-400 cm, erect;

nodes pilose.

glabrous or pubescent;

ligules 1-3.2 mm;

blades to 31 cm long, 4-18 mm wide, flat, glabrous, with a few hairs behind the ligules.

papillose-hirsute (upper sheaths sometimes glabrous);

ligules 1-4.5 mm;

blades 30-50 cm long, 10-23 mm wide, flat, with long hairs behind the ligules, otherwise glabrous or puberulent adaxially.

terminal, with 2-7 racemosely arranged branches;

branches 2.2-7.9 cm, divergent to spreading, terminating in a spikelet;

branch axes 1.1-2.3 mm wide, narrowly winged, glabrous, margins scabrous.

terminal, with (6)15-44 racemosely arranged branches;

branches 5-13 cm, straight, spreading to reflexed, rarely merely divergent;

branch axes 0.3-0.4 mm wide, narrowly winged, glabrous, margins scabrous, pubescent, terminating in a spikelet.

2.8-3.6 mm long, 1.5-2 mm wide, paired, imbricate, appressed to divergent from the branch axes, elliptic to obovate, pubescent or glabrous, light brown to stramineous.

2-2.5 mm long, 1.8-1.9 mm wide, paired, divergent to spreading from the branch axes, elliptic, brown to stramineous, often purple-tinged.

absent;

upper glumes and lower lemmas glabrous or sparsely pubescent, hairs shorter than 0.1 mm, 3-veined, margins entire;

lower lemmas lacking ribs over the veins;

upper florets stramineous.

usually absent, if present, to 0.9 mm, triangular;

upper glumes smooth, papillose-hirsute, 3-veined;

lower lemmas smooth, papillose-hirsute or glabrous, 3-veined;

upper florets white.

1.8-2 mm, golden brown or white.

= 60, ca. 64.

= 20, 40, 60.