Flora of North America species comparison

50-100 cm, glabrous, somewhat glaucous;

nodes usually exposed.

usually hollow, sometimes solid.

closed for less than 1/3 their length, glabrous or sparsely pubescent, shredding into fibers;

ligules 0.5-1 mm;

blades 2-10 mm wide, flat, loosely conduplicate, or involute, abaxial surfaces smooth or scabrous, glabrous or puberulent, adaxial surfaces smooth or scabrous, veins 13-35, ribs obscure;

sclerenchyma in abaxial and adaxial strands;

girders formed at most major veins.

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.

(8)10-30(40) cm, open, with 1-2 branches per node;

branches lax, spreading, spikelets borne towards the ends of branches.

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.

6-11 mm, sometimes glaucous, with (2)3-5 florets.

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.

lanceolate, smooth or scabrous, acuminate;

lower glumes 4-7 mm;

upper glumes 5-7.5 mm;

lemmas 5-8 mm, chartaceous, lanceolate, glabrous, usually smooth, sometimes scabrous towards the apices, apices acute to acuminate, unawned, sometimes mucronate;

paleas as long as or slightly shorter than the lemmas, intercostal region puberulent distally;

anthers 2-3 mm;

ovary apices densely pubescent.

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.

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.