Flora of North America species comparison

20-90 cm tall, 1.8-2.8 mm thick, erect, rigid, simple or branching from the lower and middle nodes;

nodes glabrous or sparsely hispid;

internodes glabrous.

annual, usually solid, sometimes somewhat woody, sometimes decumbent, often branched above the base.

generally shorter than the internodes, not keeled, lower nodes glabrous or hispid, hairs papillose-based, particularly near the summits;

ligules 0.5-1 mm;

blades 3-25 cm long, 2-8 mm wide, often distichous, flat to slightly involute, firm, adaxial surfaces pilose basally, glabrous or sparsely pubescent abaxially.

distichous;

sheaths usually open;

auricles usually absent;

abaxial ligules usually absent, occasionally present as a line of hairs;

adaxial ligules membranous, sometimes also ciliate, or of hairs, sometimes absent;

blades sometimes pseudopetiolate;

mesophyll radiate or non-radiate;

adaxial palisade layer absent;

fusoid cells usually absent;

arm cells usually absent;

kranz anatomy absent or present;

midribs usually simple, rarely complex;

adaxial bulliform cells present;

stomata with triangular or dome-shaped subsidiary cells;

bicellular microhairs usually present, with a long, narrow distal cell;

papillae absent or present.

3-24 cm long, usually less than 5 cm wide, open;

primary branches 2-11 cm, alternate, few, stiffly ascending to spreading;

pedicels 1-6 mm, subappressed.

ebracteate (Paniceae) or bracteate (most Andropogoneae) panicles, racemes, spikes, or complex arrangements of rames (in the Andropogoneae), usually bisexual, sometimes unisexual;

disarticulation usually below the glumes, frequently in the secondary and higher order axes of the inflorescences.

2.2-2.8 mm long, 0.8-1.3 mm wide, ellipsoid-ovoid, pale green, acute, upper glumes and lower lemmas sometimes separating (gaping) beyond the florets.

bisexual or unisexual, frequently paired or in triplets, the members of each unit usually with pedicels of different lengths or 1 spikelet sessile.

usually 2, equal or unequal, shorter or longer than the adjacent florets, sometimes exceeding the distal florets;

florets 2(-4), usually dorsally compressed, sometimes terete or laterally compressed;

lower florets sterile or staminate, frequently reduced to a lemma;

upper florets usually bisexual;

lemmas hyaline to coriaceous, lacking uncinate hairs, often terminally awned;

awns single;

paleas of bisexual florets well-developed, reduced, or absent;

lodicules usually 2, sometimes absent, cuneate, free, fleshy, usually glabrous;

anthers 1-3;

ovaries usually glabrous;

haustorial synergids absent;

style branches 2, free and close or fused at the base.

0.5-1 mm, 1/5 – 2/5 as long as the spikelets, glabrous, faintly 1-5-veined, subtruncate to broadly acute;

upper glumes and lower lemmas glabrous, extending 0.1-0.5 mm beyond the upper florets, scarcely separated;

upper glumes 7-11-veined, shorter than the lower lemmas, acute to short-acuminate;

lower florets staminate;

lower lemmas 7-11-veined;

lower paleas 1.9-2.1 mm, oblong;

upper florets 1.8-2.7 mm long, 0.7-1.3 mm wide, broadly ellipsoid, broadest at or above the middle, glabrous, shiny, smooth, apices rounded.

hila usually punctate;

endosperm hard, without lipid;

starch grains simple;

embryos large in relation to the caryopses, usually waisted;

epiblasts usually absent;

scutellar cleft present;

mesocotyl internode elongated;

embryonic leaf margins usually overlapping, rarely just meeting, x = 5, (7), 9, 10, (12), (14).

- 36, 40, 45, 54.