Flora of North America species comparison

30-130 cm, erect to slightly decumbent;

nodes 4-9, concealed or exposed, usually glabrous, rarely pubescent.

22-130 cm, erect;

nodes glabrous.

evenly distributed;

sheaths usually glabrous, rarely hirsute, occasionally reddish or purplish;

auricles absent or to 1.8 mm, pale brown;

ligules shorter than 1 mm;

blades 2-14(18) mm wide, usually spreading or lax, sometimes becoming involute, basal blades similar to the upper blades, adaxial surfaces usually smooth, sometimes scabridulous, usually glabrous, occasionally pubescent.

often mostly basal, sometimes more evenly distributed;

sheaths glabrous or pubescent;

auricles usually present on the lower leaves, 0.5-1.5 mm;

ligules 0.1-0.5 mm, erose, sometimes ciliolate;

blades 1.5-6 mm wide, generally involute, abaxial surfaces usually glabrous, adaxial surfaces strigose, ribs subequal in size and spacing.

(3)4-16(22) cm long, 1-2.2(2.5) cm wide, erect, the bases often sheathed, with 2 spikelets per node, rarely with 3 at some nodes;

internodes 3-5 mm long, 0.25-0.5 thick at the thinnest sections, smooth and glabrous, or scabrous, or with hairs beneath the spikelets.

3.5-26 cm long, 0.5-1 cm wide, erect to slightly nodding, usually with 1 spikelet per node, sometimes with 2 at a few nodes;

internodes 3.5-15 mm long, 0.1-0.8 mm wide, glabrous or hairy.

10-15 mm, appressed to slightly divergent, with (2)3-4(6) florets, lowest florets functional;

disarticulation below the glumes and each floret, or the lowest floret falling with the glumes.

8-31 mm, 1.5-3 times longer than the internodes, appressed, with 3-11 florets;

rachillas glabrous or hairy, hairs to 1 mm;

disarticulation above the glumes, beneath each floret.

subequal or equal, the basal 1-4 mm terete, indurate, without evident venation, bowed out, yellowish, glume bodies 7-15 mm long, (0.5)0.7-2.3 mm wide, linear-lanceolate, widening above the base, 3-5(8)-veined, usually smooth or scabridulous, margins firm, awns 3-10(15) mm, straight;

lemmas 6-10 mm, scabridulous, glabrous or villous-hirsute, awns (5)8-20(25) mm, straight;

paleas 5-9 mm, obtuse;

anthers 2-3.5(4) mm.

subequal, 5-14 mm long, 1/2 - 3/4 the length of the adjacent lemmas, 0.7-1.3 mm wide, lanceolate, glabrous or hairy, smooth or scabrous, 3-5-veined, flat or weakly, often asymmetrically keeled, keels straight, margins narrow, tapering from the base or from beyond midlength, apices acute to acuminate, sometimes mucronate or shortly awned;

lemmas 7-12 mm, glabrous or hairy, hairs all alike, sometimes scabrous, acute to awn-tipped, awns to 2 mm, straight;

paleas about equal to the lemmas, keels straight below the apices, smooth or scabrous proximally, sometimes hairy, scabrous distally, intercostal region glabrous or with hairs, apices 0.2-0.3 mm wide;

anthers (2.5)3-6 mm.

usually mid-June to late July (mid-August).

= 28.

= 28.