Flora of North America species comparison

70-100 cm, erect, mostly unbranched.

10-100 cm, erect to ascending, usually unbranched.

cauline;

sheaths mostly longer than the internodes, mostly glabrous, summit with hairs;

collars mostly glabrous, sides usually with straight or wrinkled hairs;

ligules 0.2-0.3 mm;

blades 30-55 cm long, 1-2 mm wide, pale yellow-green, loosely involute, lax, glabrous abaxially, with scattered hairs adaxially.

mostly basal or mostly cauline;

sheaths shorter or longer than the internodes, glabrous, not disintegrating into threadlike fibers at maturity;

collars glabrous, or sparsely pilose at the sides with straight hairs;

ligules less than 0.5 mm;

blades 4-25 cm long, 1-1.5 mm wide, tightly involute to flat, usually glabrous, sometimes scabridulous abaxially, gray-green, lax to curled at maturity.

paniculate, 30-45 cm long, 5-25 cm wide, oblong to ovate;

primary branches single or paired, ascending and somewhat lax to stiffly divergent, with weakly developed axillary pulvini, spikelet-bearing to the base;

lowermost branches to 15 cm.

usually sparingly branched panicles, occasionally racemes, 3-30 cm long, 2-12 cm wide, with 2 or more spikelets per node;

nodes glabrous or with straight, about 0.5 mm hairs;

primary branches 3-6 cm, appressed to divaricate, varying sometimes within a panicle, stiff to flexible, bases appressed or abruptly spreading, usually without axillary pulvini.

mostly appressed.

divergent or appressed, with or without axillary pulvini.

purplish-tinged, 1-veined;

lower glumes 10-14 mm;

upper glumes 8-9 mm;

calluses 0.5-0.7 mm;

lemmas 8-12 mm, gray mottled with purple or dark patches, narrowing to a slightly curved and twisted beak, junction with the awns not strongly marked;

awns not disarticulating at maturity;

central awns 10-25 mm, falcate;

lateral awns absent;

anthers 3, about 1 mm, brown.

usually unequal, lower glumes shorter than the upper glumes, sometimes subequal, light to dark brown or purplish, glabrous, smooth or scabridulous, 1(2)-veined, acuminate, unawned or awned, awns to 1 mm;

lower glumes 4-12 mm;

upper glumes 7-25 mm;

calluses 0.5-1.8 mm;

lemmas 6-16 mm, glabrous, scabridulous, or tuberculate, whitish to purplish, apices 0.1-0.8 mm wide, not beaked or the beak less than 3 mm, junction with the awns not conspicuous;

awns (8)13-140 mm, ascending to divaricate, not disarticulating at maturity;

central awns thicker than the lateral awns;

lateral awns (8)13-140 mm, usually subequal to the central awns, occasionally less than 1/3 as long as the central awns;

anthers 3, 0.7-2 mm.

6-7 mm, chestnut-colored.

6-14 mm, tan to chestnut.

= unknown.

= 22, 44, 66, 88.