OregonFlora species comparison

with bases somewhat compressed-keeled;

internodes glabrous; shiny below the nodes.

usually herbaceous; erect to sprawling;

internodes hollow or solid;

nodes prominent and usually swollen.

blades 2–7(11) cm × 1–2.8(4)mm; flat, occasionally conduplicate;

lower surface smooth or minutely scabrous;

upper surface minutely scabrous;

margins and midveins not conspicuously thickened; greenish;

tips acute.

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.

6–21 × 4–16 cm, broadly ovoid; open;

branches whitish;

primary branches 3–12 cm × 0.05–0.1 mm; capillary; lower branches spreading, not appearing clustered;

pedicels 3–14 mm; longer than the spikelets.

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.

1.2–2.1 mm.

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

equal, 0.6–1.7 mm, 1-veined; purplish, minutely scabrous particularly on the veins;

tips acute.

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

(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.

1.2–2.1 mm, lanceolate to oblong-elliptic; somewhat gray, glabrous; smooth, occasionally minutely scabrous near the tips;

tips acute; awnless or mucronate; the mucros to 0.3 mm.

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.

1–1.3 mm; greenish yellow to purplish at maturity.

usually 2-keeled, often with additional veins.

=20, 22, 28.