Festuca idahoensis Herbaceous Alliance
Idaho fescue grassland

USDA Ecological Section Map

Summary Information

  • Primary Life FormHerb
  • Elevation20-2500 m
  • State RarityS3?
  • Global RarityG4
  • DistributionCAN: AB. USA: CA, CO, ID, MT, NV, OR, UT, WA, WY (NatureServe)
  • Endemic to CaliforniaNo
  • Endemic to California Floristic Province and DesertsNo
  • Date Added1995/11/01

Characteristic Species

Festuca idahoensis is dominant or co-dominant in the herbaceous layer with Achillea millefolium, Anthoxanthum odoratum, Arrhenatherum elatius, Bromus carinatus, Carex tumulicola, Danthonia californica, Festuca rubra, Holcus lanatus, Melica californica, Nassella pulchra, Poa secunda and Pteridium aquilinum. Emergent trees and shrubs may be present at low cover.

Vegetation Layers

Herbs < 1 m; cover is intermittent to continuous.

Membership Rules

  • Festuca idahoensis is characteristically present and usually > 30% relative cover with other perennial grasses in the herbaceous layer (Evens and Kentner 2006).


Many landforms, aspects, and soil types. The USFWS Wetland Inventory (1996 national list) recognizes Festuca idahoensis as an UPL plant.

Other Habitat, Alliance and Community Groupings

MCV (1995) Idaho fescue series
NVCS (2009) Festuca idahoensis herbaceous alliance
Calveg Perennial grasses and forbs
Holland Bald Hills prairie, Serpentine bunchgrass, Great Basin grassland
Munz Coastal prairie
WHR Perennial grassland
CDFW CA Code 41.250.00

National Vegetation Classification Hierarchy

Formation Class Mesomorphic Shrub and Herb Vegetation (Shrubland and Grassland)
Formation Subclass Temperate and Boreal Shrubland and Grassland
Formation Temperate Grassland, Meadow, and Shrubland
Division Vancouverian and Rocky Mountain Grassland and Shrubland
Macro Group Western North American Temperate Grassland and Meadow
Group Western dry upland perennial grassland