OregonFlora species comparison

erect or decumbent, sometimes with saucer-like glands below the nodes.

usually herbaceous; erect to sprawling;

internodes hollow or solid;

nodes prominent and usually swollen.

sheaths glabrous or occasionally glandular; tops with hairs to 5 mm;

blades (1)5–20 cm × (1)3–5(10)mm;

lower surfaces glabrous or sometimes glandular;

margins with conspicuous glands.

alternate, 2-ranked; each consisting of a sheath that encircles the culm and a blade;

sheaths open or closed with margins fused for much or all of their lengths;

auricles present or absent;

ligules usually present at the sheath-blade junction; on the side toward the culm, membranous or of hairs, rarely absent;

blades usually linear to lanceolate with parallel veins.

(3)5– 16(20) × 2–8.5 cm, oblong to ovate, condensed to open;

primary branches 0.4–5 cm, appressed or diverging 20–80° from the inflorescence axis;

pedicels 0.2–3 mm; stout; straight; stiff, usually divergent, occasionally appressed;

disarticulation below the florets; each floret falling as a unit;

rachillas persistent.

usually complex aggregations of spikelets into panicles; racemes, or spikes, usually with a main axis;

spikelets usually supported on pedicels;

disarticulation above or below the glumes, usually beneath each floret, sometimes in or below the inflorescence axis.

6–20 × 2–4 mm, gray or greenish, 10–40 florets.

consisting of 2 glumes subtending 1–many florets arranged on either side of the rachilla, laterally or dorsiventrally compressed, occasionally round in cross section.

broadly ovate to lanceolate, membranous, usually glandular;

lower glumes 1.2–2 mm, usually 1-veined;

upper glumes 1.2–2.6 mm, usually 3-veined.

(0)2, with an odd number of veins, sometimes awned.

0.5–0.7 mm, globose to broadly ellipsoid, not grooved.

(0)3(6).

usually bisexual, sometimes pistillate, staminate or sterile, usually consisting of a lemma and palea with the flower between them; the flower itself reduced to stamens; a pistil; and 2 lodicules.

usually a caryopsis.

2–2.8 mm, broadly ovate, membranous;

keels with 1–3 saucer-like glands, obtuse to acute.

usually with an odd number of veins, awned or awnless, with calluses;

lemma awns; if present, arising at the tip; along the back or near the base, sometimes curved; bent, or twisted.

1.2–2.1 mm; hyaline;

keels scabrous or sometimes also ciliate.

usually 2-keeled, often with additional veins.

3, 0.2–0.5 mm, yellow.

=20.