OregonFlora species comparison

orange-brown at the base.

usually herbaceous; erect to sprawling;

internodes hollow or solid;

nodes prominent and usually swollen.

sheaths mostly glabrous;

throats densely hairy;

basal sheaths reddish brown, becoming flat with age; lower ligules 0.3–1 mm, densely hairy;

hairs 0.2–1 mm; upper ligules to 2.5 mm; hyaline to scarious, glabrous or hairy;

blades 10–30 cm × 0.5–2 mm when flat but usually rolled or convolute and to 1 mm in diameter;

outer surfaces glabrous;

inner surfaces with spreading hairs.

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.

congested, 10–15 cm;

branches ascending.

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.

terete or slightly laterally compressed, 16–24 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.

tapering from below mid length, glabrous;

tip narrowly acute; awnless;

lower glumes 16–24 mm, 1-veined;

upper glumes 13–19 mm, 3–5-veined.

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

(0)3(6).

(6)8–10 mm, 0.6–0.8 mm thick.

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.

sharp, 0.8–1.6(3) mm; hairy.

densely and evenly hairy;

hairs approximately 0.5 mm;

lemma awns bent once, 35–45(80) mm; first segment with spreading hairs 3–8 mm; terminal segment glabrous; smooth.

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.

3.2– 5.1 mm, approximately 50% as long as the lemma.

usually 2-keeled, often with additional veins.

1–3 mm long; a tuft of hairs at the tip.

=66, 68; ±74.