Flora of North America species comparison

(3)10-50(80) cm, often highly branched above the base.

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

cauline, glabrous;

sheaths shorter than the internodes, not disintegrating into threadlike fibers;

ligules 0.4-1 mm;

blades 2-14 cm long, 1-2.5 mm wide, flat to involute.

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.

panicles, 5-15(20) cm long, 0.5-3 cm wide, often interrupted below;

nodes glabrous or with straight, less than 0.5 mm hairs;

primary branches 1-4 cm, erect to ascending, without axillary pulvini, with 3-8 spikelets.

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.

crowded.

divergent or appressed, with or without axillary pulvini.

unequal, 1-veined, acuminate;

lower glumes 4-8 mm;

upper glumes 6-11 mm;

calluses 0.5-0.8 mm;

lemmas 6-9 mm, slightly keeled, midveins scabrous, junction with the awns not evident;

awns not disarticulating at maturity, flattened and straight to somewhat curved at the base, central rib flanked by equally wide pale wings;

central awns 7-15(20) mm;

lateral awns somewhat shorter, occasionally only 1-2 mm;

anthers 3, 0.3-0.7 mm.

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.

6-14 mm, tan to chestnut.

= 22.

= 22, 44, 66, 88.