Flora of North America species comparison

20-100 cm.

10-600 cm, erect or decumbent.

compressed, glabrous, margins villous distally;

ligules 1-2.5 mm, ciliate;

blades 8-25 cm long, 2-5 mm wide, flat or folded, scabrous on both surfaces.

6-15 cm, tightly spikelike, pale green;

rachises scabrous or villous;

bristles usually solitary, 4-15 mm, ascending.

terminal, panicles, usually dense and spikelike, occasionally loose and open;

disarticulation usually below the glumes, spikelets falling intact, bristles persistent.

2.2-2.8(3) mm, elliptical.

1-5 mm, usually lanceoloid-ellipsoid, rarely globose, turgid, subsessile to short pedicellate, in fascicles on short branches or single on a short branch, some or all subtended by 1-several, terete bristles (sterile branchlets).

about 1/2 as long as the spikelets, 3-veined;

upper glumes from 3/4 as long as to equaling the florets, 5-veined;

lower lemmas equaling the upper lemmas, 5-veined;

lower paleas 1/2 - 3/4 as long as the upper paleas, lanceolate;

upper lemmas apiculate, finely and transversely rugose;

upper paleas similar.

membranous, not saccate, less than 1/2 as long as the spikelets, 1-7-veined;

upper glumes membranous to herbaceous at maturity, 1/2 as long as to nearly equaling the upper lemmas in length, 3-9-veined;

lower florets staminate or sterile;

lower lemmas membranous, equaling or rarely exceeding the upper lemmas, rarely absent, not constricted or indurate basally, 5-7-veined;

lower paleas usually hyaline to membranous at maturity, rarely absent or reduced, veins not keeled;

upper florets bisexual;

upper lemmas and paleas indurate, transversely rugose, rarely smooth;

anthers 3, not penicillate;

styles 2, free or fused basally, white or red.

small, ellipsoid to subglobose, compressed dorsiventrally.

membranous and ciliate or of hairs;

blades flat, folded, or involute, or plicate and petiolate (subg. Ptychophyllum).

= 9.

= 54, 68, 72.