Scientific Name
Festuca idahoensis Elmer
Common Name(s)
Idaho fescue
Tribe / Family Name
Poeae
Flowering Period
Late May to August
Symbol
FEID
Description
Idaho fescue is a native cool-season perennial bunchgrass that reproduces from seeds and tillers. Culms usually range from 25–85 cm tall and glaucous. Its inflorescence is a loosely contracted or open panicle usually 7–15 cm long with erect to ascending branches. Spikelets are usually 7.5–13.5 mm long, somewhat flattened, loosely 4- to 7-flowered (rachilla joints usually visible), and awned (the lemma awns usually 2–6 mm long). Ligules are 0.2–0.6 mm long, membranous, ciliolate, glabrous, and longer on the sides.
General Info
This vigorous, long-lived grass can be found in open woodlands and grasslands, sagebrush steppe, rocky slopes, meadows, foothills, plains, and alpine sites.
Similar Species
Idaho fescue looks similar to other fescue (Festuca) species, because most of them have enrolled basal leaves and usually contracted to open panicle inflorescences. Remember to look for spikelets that are loosely 4- to 7-flowered, lemma awns up to 6 mm long, and black roots to distinguish Idaho fescue from other fescues.
Picture of growth habit.
Close-up picture of loosely contracted panicle inflorescence (example of immature growth).
Close-up picture of open panicle inflorescence (example of mature growth).
Close-up picture of spikelet.
Close-up picture of membranous ligule.
Close-up picture of black, fibrous roots.
Illustration of Idaho fescue. USDA-NRCS PLANTS Database / Hitchcock, A.S. (rev. A. Chase). 1950. <i>Manual of the grasses of the United States</i>. USDA Miscellaneous Publication No. 200. Washington, DC.