Flora of North America species comparison

22-130 cm, erect;

nodes glabrous.

25-100 cm tall, 1.3-3.5 mm thick, erect;

nodes 4-6, glabrous.

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.

basal and cauline;

sheaths glaucous, glabrous or with hairs, margins glabrous or ciliate distally;

auricles 1-2 mm;

ligules 0.2-0.7 mm, truncate;

blades 3-10 mm wide, flattish, often glaucous.

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.

(6.5)10-25 cm long, 1.4-4 cm wide including the awns, 0.7-20 cm wide excluding the awns, flexuous, nodding;

rachises densely to sparsely hirsute on the edges, hairs about 0.2 mm, glabrous elsewhere, glaucous;

internodes (5)8-20 mm.

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.

15-25 mm, loosely appressed or ascending, with 5-10 florets;

rachillas hairy, hairs about 0.1 mm;

disarticulation above the glumes, beneath the florets.

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.

lanceolate, tapering from about midlength, adaxial surfaces glabrous, hyaline margins about 0.1 mm wide, strongly keeled distally, midvein scabrous distally, other veins smooth or scabrous, apices acute to acuminate, sometimes awned, awns 2-5 mm;

lower glumes 4-7 mm, 3-5-veined;

upper glumes 5-8 mm, 5-veined;

calluses glabrous;

lemmas 8-12 mm, lanceolate, glabrous or pilose, apices acute, awned, awns 20-40 mm, straight or flexuous;

paleas from slightly shorter than to longer than the lemmas, keels narrowly winged distally, not or scarcely extending beyond the intercostal region, distinctly outwardly curved below the apices, apices 0.3-0.5 mm wide;

anthers 1.5-2.5 mm.

= 28.

= 42.