Flora of North America species comparison

60-160 cm, thickened basally, sometimes appearing cormous;

internodes sometimes pubescent below the nodes.

usually hollow, sometimes solid.

usually glabrous, sometimes pilose or retrorsely scabrous, particularly at the throat, veins often prominent;

ligules 2-4 mm;

blades 15-25 cm long, 5-12 mm wide, both surfaces usually scabridulous, glabrous, sometimes the adaxial surfaces with hairs.

distichous;

sheaths usually open to the base, varying to closed for nearly their full length;

auricles present or absent;

abaxial ligules absent;

adaxial ligules scarious or membranous, sometimes puberulent or scabridulous, usually not ciliate, cilia sometimes shorter than the base;

pseudopetioles rarely present;

blades usually linear, sometimes broadly so, venation parallel;

cross sections non-Kranz, mesophyll nonradiate, adaxial palisade layer absent, fusoid and arm cells usually absent;

midribs usually simple;

adaxial bulliform cells present;

stomates with parallel-sided subsidiary cells;

epidermes usually lacking bicellular microhairs, sometimes with unicellular microhairs, papillae usually absent, when present, rarely more than 1 per cell.

12-30 cm;

branches 7-11 cm, spreading to reflexed, with 4-7 spikelets, spikelets restricted to the distal portion, axils frequently with brownish pulvini;

pedicels straight;

disarticulation above the glumes.

usually terminal, panicles, spikes, or racemes, usually ebracteate;

disarticulation usually below the florets, sometimes below the glumes, at the rachis nodes, or at the inflorescence bases.

12-18 mm, with 3-5 bisexual florets;

rachilla internodes 2.5-3 mm.

usually bisexual, infrequently unisexual or mixed, usually laterally compressed or not compressed, occasionally dorsally compressed, with 1-30 sexual florets, distal floret(s) often reduced, infrequently spikelets with 1-2 reduced or staminate basal florets and a single terminal sexual floret.

usually 2, upper or lower glumes sometimes absent, rarely both glumes absent;

lemmas without uncinate hairs, awned or not, awns single, basal to apical;

paleas usually well-developed, sometimes reduced or absent;

lodicules 2(3), usually lanceolate and broadly membranous distally, rarely truncate and fleshy, usually not veined or obscurely veined, sometimes distinctly veined, sometimes ciliate;

anthers (1, 2)3;

ovaries glabrous or sometimes hairy distally, sometimes with an apical appendage;

haustorial synergids absent;

styles (1)2 (-4), bases close together, sometimes fused.

4.5-7 mm long, 1-1.5 mm wide, 1-3-veined;

upper glumes 6.5-9 mm long, 1.2-1.8 mm wide, 3-5-veined;

lemmas 9.5-12 mm, glabrous or scabrous, 7-veined, apices bifid to emarginate, awned, awns 3-10 mm;

paleas about 2/3 the length of the lemmas;

anthers 1.3-2.5 mm;

rudiments 3.5-6 mm, tapering, resembling the bisexual florets.

hila linear, elliptic, ovate, or punctate;

endosperm usually hard, sometimes soft or liquid, with or without lipids, starch grains compound or simple;

embryos less than 1/2 the length of the caryopses;

epiblasts usually present;

scutellar cleft usually absent;

mesocotyl internode usually absent;

embryonic leaf margins overlapping, x = 7, 10.

= unknown.