Flora of North America species comparison

30-90 cm, glabrous;

basal branching mostly intravaginal.

10-140(150) cm, erect, usually glabrous, usually smooth;

nodes 1-6; branching intra- or extravaginal at the base, not branching above the base;

prophylls concealed by the leaf sheaths.

basally concentrated;

sheaths smooth or scabridulous;

ligules 1-4 mm, hyaline, truncate, rounded, or acute;

basal blades 4-15 cm long, 1-1.5 mm wide when flat, 0.5-0.8 mm in diameter when folded or convolute.

sometimes basally concentrated;

cleistogenes not present;

sheaths open, glabrous, smooth to scabrous;

auricles absent;

ligules 0.2-15 mm, membranous to hyaline;

blades 0.5-16 mm wide, flat, involute, valvate, or folded, often tapering in the distal 1/3, apices acute to acuminate, not stiff, basal blades not overwintering, sometimes not developed, flag leaf blades well developed, longer than 1 cm.

9-15 cm, lower nodes with 1-2 branches;

branches 1-6 cm, somewhat flexuous, ascending to divergent.

3-40 cm, terminal panicles, open or contracted;

branches straight or flexuous, usually scabrous, rarely smooth;

pedicels often appressed to the branches.

1.5-7.5 mm, with 1 floret;

rachillas not prolonged beyond the floret;

disarticulation above the glumes, beneath the floret.

subequal, 3-6 mm long, 1.3-2 mm wide, ovate, 1-3-veined, apices acute to mucronate;

florets 2.2-4.5 mm, obovoid, dorsally compressed;

calluses 0.2-0.5 mm, hairy, disarticulation scars elliptic;

lemmas coriaceous, evenly pubescent, tan at maturity, margins widely separated even when immature;

awns 5-15 mm, persistent, once- or twice-geniculate, first segments strongly twisted;

paleas similar to the lemmas in length, texture, and pubescence;

anthers 1-2 mm;

ovaries developing 2 conelike style bases, each bearing a single, unbranched style.

from 1 mm shorter than to exceeding the florets, subequal or the lower glumes longer than the upper glumes, membranous, 1-9-veined, veins evident, apices obtuse to acute or acuminate;

florets 1.5-10 mm, usually dorsally compressed, sometimes terete;

calluses 0.1-0.6 mm, glabrous or with hairs, blunt;

lemmas 1.2-9 mm, smooth, coriaceous or stiffly membranous, tawny or light brown to black at maturity, 3-7-veined, margins flat, separated and parallel for their whole length at maturity, apices not lobed or lobed, glabrous or hairy, hairs about 0.5 mm, not spreading, awned, lemma-awn junction evident;

awns 1-18(20) mm, centric, often caducous, almost straight to once- or twice-geniculate, scabrous;

paleas as long as or slightly longer than the lemmas, similar in texture and pubescence, 2(3)-veined, not keeled over the veins, flat between the veins, veins terminating near the apices, apices often pinched;

anthers 3, 0.6-5 mm, sometimes penicillate;

styles 2 and free to their bases, or 1 with 2-3 branches.

about 2.5 mm long, 0.5 mm thick;

hila linear, almost equaling the caryopses.

glabrous, ovoid to obovoid;

hila 1/2 as long as to equaling the length of the caryopses.

= 11, 12.

= 22.