Oryzopsis exigua

HABIT Perennial; caespitose. Culms erect; 10–30 cm long. Leaf-sheaths smooth, or scaberulous. Ligule an eciliate membrane; 3–4 mm long; pubescent on abaxial surface; acute. Leaf-blades erect; filiform; involute; 5–10 cm long; 1 mm wide.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted; linear; 3–6 cm long. Primary panicle branches appressed.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; 4–6 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus pubescent; obtuse.

GLUMES Glumes persistent; similar; reaching apex of florets; thinner than fertile lemma. Lower glume ovate; 4–6 mm long; 1 length of upper glume; hyaline; without keels; 3–5 -veined. Lower glume lateral veins obscure. Lower glume apex acute. Upper glume ovate; 4–6 mm long; 1 length of adjacent fertile lemma; hyaline; without keels; 3–5 -veined. Upper glume lateral veins obscure. Upper glume apex acute.

FLORETS Fertile lemma elliptic; dorsally compressed; 4–6 mm long; coriaceous; without keel. Lemma surface pubescent. Lemma margins convolute; covering most of palea. Lemma apex dentate; 2 -fid; obtuse; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 4–6 mm long overall; with a straight or slightly twisted column; deciduous. Palea 1 length of lemma; coriaceous; 2 -veined; without keels.

FLOWER Lodicules 2; 1.5 mm long. Anthers 3; 1.5–2 mm long. Styles connate below.

FRUIT Caryopsis apex rostrate.

DISTRIBUTION North America: western Canada, northwest USA, and southwest USA.

NOTES Stipeae. Fl Pac NW 1994.

Please cite this publication as detailed in How to Cite Version: 3rd February 2016.