Flora of North America species comparison

20-250 cm tall, 3-10 mm thick, erect or decumbent, simple or branched from the lower nodes;

nodes glabrous;

internodes glabrous, glaucous.

2-300 cm, herbaceous, sometimes hard and almost woody, or woody, simple or branched, bases sometimes cormlike;

internodes solid, spongy, or hollow.

shorter or longer than the internodes, not keeled, glabrous;

collars often glaucous and purplish;

ligules 1-5 mm;

blades 7-50 cm long, 2-13 mm wide, erect or ascending, firm, thick, flat basally, more or less involute towards the apices.

cauline, basal, or both, basal leaves not forming a winter rosette;

ligules membranous, usually ciliate;

blades filiform to ovate, flat to involute, glabrous or pubescent, cross sections with Kranz anatomy and 1 or 2 bundle sheaths or with non-Kranz anatomy;

photosynthesis C4 with NAD-me or NADP-me pathways, or, in plants with non-Krantz anatomy, C3.

10-80 cm long, 2-17 cm wide, contracted, slightly nodding;

primary branches whorled or opposite, strongly ascending to appressed;

pedicels 0.5-15 mm, appressed to slightly divergent.

terminal on the culms and branches, often also axillary, terminal panicles typically appearing after midsummer;

sterile branches and bristles absent;

disarticulation usually below the glumes, sometimes at the base of the upper florets, if at the base of the upper florets, then the florets not very plump at maturity.

4-7.7 mm long, 1.5-2 mm wide, narrowly ovoid, glabrous, acuminate;

lower florets staminate.

1-8 mm, usually dorsally compressed, sometimes subterete or laterally compressed, unawned.

and lower lemmas relatively thick;

lower glumes 2.8-4 mm, 1/2 - 4/5 as long as the spikelets, 3-9-veined, apices of the midveins sometimes scabridulous;

upper glumes and lower lemmas extending 1.5-3 mm beyond the upper florets, apices stiffly gaping;

upper glumes 3.9-7.6 mm, 5-9-veined;

lower lemmas slightly shorter than the upper glumes, 7-9-veined, lower paleas 3-7 mm, oblong-hastate, folded over the anthers;

lower florets staminate;

upper florets 2.4-3.9 mm long, 1-1.8 mm wide, narrowly ovoid to oblong, glabrous, smooth, shiny, lemma margins clasping the paleas only at the base.

usually unequal, herbaceous, glabrous or pubescent, rarely tuberculate or glandular, apices not or only slightly gaping at maturity;

lower glumes minute to almost equaling the spikelets, 1-9-veined, truncate, acute, or acuminate;

upper glumes slightly shorter to much longer than the spikelets, 3-13(15)-veined, bases rarely slightly sulcate, apices rounded to attenuate;

lower florets sterile or staminate;

lower lemmas similar to the upper glumes;

lower paleas absent, or shorter than the lower lemmas and hyaline;

upper florets bisexual, sessile or stipitate, apices acute, puberulent, or with a tuft of hairs;

upper lemmas usually more or less rigid and chartaceous-indurate, usually shiny, glabrous or (rarely) pubescent, usually smooth, sometimes verrucose or transversely rugose, margins involute, usually clasping the paleas, rarely with basal wings or lunate scars, apices obtuse, acute, apiculate, or with small green crests;

upper paleas striate, rarely transversely rugose;

lodicules 2;

anthers usually 3.

smooth;

pericarp thin;

endosperm hard, without lipid, starch grains simple or compound, or both;

hila round or oval, x = 9 (usually), sometimes 10, with polyploid and dysploid derivatives.

= 36, 54.