Festuca occidentalis Hook.

Family: Poaceae, Tribe: Poeae

Pertinent Synonyms & Notes (particularly those used in California; go to GRIN for other synonyms)


Pertinent Common Names (particularly those used in California; go to GRIN for other common names)

western fescue

Primary Disseminule Type


Description (diagnostics are in brown)

Spikelets solitary, pedicelled, consisting of (2)3–6(7) fertile florets with similar-looking though diminished sterile florets at apex, oblong, laterally compressed, 6–12 mm long. Disarticulation below each fertile floret.

Glumes persistent, similar, shorter than spikelet, ovate to ovate-lanceolate, chartaceous, without keel, surface glabrous and smooth or slightly scabrous, apices acute. Lower glume 2–4(5) mm long, 0.8–0.9 length of upper glume, 1-veined, lateral veins absent. Upper glume 3–4.5(6) mm long, 0.7–0.8 length of adjacent fertile lemma, 3-veined.

Fertile florets: rachilla persistent, scaberulous, callus blunt, glabrous.

Lemma ovate-lanceolate to attenuate, 4–8 mm long, chartaceous, without keel, 5-veined, lateral veins obscure, surface glabrous and smooth or finely puberulent and scaberulous, apex acuminate, awn apical, flexuous, 3–12 mm long, usually longer than the lemma body (but easily broken).

Palea same length as lemma, 2-veined, intercostal region scabrous to puberulent on distal third, keels scabrous.

Caryopsis narrowly elliptic, ca. 4.5 mm long x ca. 0.8 mm wide, dark purplish-brown, embryo <0.33 length of caryopsis, hilum linear, same length as caryopsis, in deep groove.

Similar Species

Similar Species Comparison Chart

Risk Assessment (codes in yellow or red indicate cause for concern; assessments are current as of mid-2011; click AUQP, NZBORIC, or NZBPI for access to the most recent versions of these databases and possible assessment changes)