OregonFlora species comparison

erect to ascending.

usually herbaceous; erect to sprawling;

internodes hollow or solid;

nodes prominent and usually swollen.

sheaths glabrous or white-villous;

blades 1.5–4 mm wide;

upper surfaces scabrous or hairy.

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.

5–20 cm; erect, sometimes partially enclosed in the sheath of the uppermost leaf, 2 spikelets per node or rarely 3–4 at some nodes;

internodes 3–5(8)mm;

disarticulation initially at the rachis nodes; later beneath each floret.

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.

10–15 mm, divergent, 2–4 florets; lowest florets sterile and glume-like in 1 or both spikelets at each node.

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

(10)30–100 mm including the awns; the bases hard and glabrous;

glume bodies about (2)5–10 × 1–2 mm, setaceous, 2–3-veined;

margins firm;

glume awns (8)25–90 mm; each split above the base into 3–9 unequal divisions, scabrous, flexuous to outcurving from near the bases at maturity.

(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.

fertile lemmas 8–10 mm; smooth or scabrous near the tips, 2 lateral veins extending into bristles to 10 mm;

lemma awns (10)20– 110 × 0.2 mm at the base, divergent to arching.

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 mm.

usually 2-keeled, often with additional veins.

=28.