Flora of North America species comparison

30-110 cm, stout, erect;

nodes glabrous.

65-400 cm, erect;

nodes pilose.

glabrous;

ligules 2-3 mm;

blades to 35 cm long, 2-5.4 mm wide, conduplicate (rarely flat).

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 1.6-7.1 cm, usually divergent, rarely merely ascending;

branch axes 0.6-1.1 mm wide, glabrous, terminating in a spikelet.

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.

2.5-3 mm long, 1.5-2.2 mm wide, paired, appressed to the branch axes, elliptic-ovate, light to dark brown.

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 usually with short, appressed pubescence, rarely glabrous, 5-veined, margins entire;

lower lemmas with short, appressed pubescence or glabrous, 3-veined, margins entire;

upper florets dark glossy brown.

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.

1.4-1.6 mm, brown.

= 20, 40, 60.

= 20, 40, 60.