Festuca idahoensis - Danthonia californica Herbaceous Alliance
Idaho fescue - California oatgrass grassland

USDA Ecological Section Map

Summary Information

  • Primary Life FormHerb
  • Elevation2-770 m
  • State RarityS3
  • Global RarityGNR
  • DistributionUSA: CA, OR, WA. (NatureServe).
  • Endemic to CaliforniaNo
  • Endemic to California Floristic Province and DesertsNo
  • Date Added2020/01/07

Characteristic Species

Danthonia californica, Festuca idahoensis and/or Festuca rubra is dominant or co-dominant in the herbaceous layer with Achillea millefolium, Aira caryophyllea, Anagallis arvensis, Arrhenatherum elatius, Avena spp., Briza maxima, Briza minor, Bromus carinatus, Bromus diandrus, Bromus hordeaceus, Chlorogalum pomeridianum, Cynosurus echinatus, Hypochaeris radicata, Koeleria macrantha, Lolium perenne ssp. multiflorum, Nassella pulchra, Plantago lanceolata, Rumex acetosella, Sisyrinchium bellum and Vulpia bromoides. Emergent trees or shrubs may be present at low cover, including Baccharis pilularis, Elymus glaucus, Pseudotsuga menziesii, Rubus ursinus or Toxicodendron diversilobum.

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).
  • Danthonia californica > 50% relative cover in the herbaceous canopy (Keeler-Wolf et al. 2003a).
  • Festuca californica, Festuca idahoensis, Festuca rubra, or Danthonia californica at least 10% relative cover and often > 30% relative cover in the herbaceous layer with a variety of other herbs in upland settings (Buck-Diaz et al. 2021).
  • Festuca rubra > 50% relative cover or most conspicuous native grass in the herbaceous layer in upland settings (Keeler-Wolf et al. 2003a).
  • Festuca idahoensis, F. californica, F. rubra, Heterotheca sessiliflora, and/or Danthonia californica > 50% relative cover in the herbaceous layer. Bromus carinatus, Elymus glaucus, Nassella pulchra, Plantago erecta, and a variety of native and non-native forbs and grasses may be < 30% relative cover (Buck-Diaz et al. 2021, Sikes et al. 2021).


Coastal bluffs, headlands, terraces, slopes, balds, and ridgetops. The USFWS Wetland Inventory (2012 national list) recognizes Festuca idahoensis as a FACU plant, and Danthonia californica as a FAC plant.

Other Habitat, Alliance and Community Groupings

MCV (1995) California oat grass series, Idaho fescue series
NVCS (2009) Danthonia californica herbaceous alliance, Festuca idahoensis herbaceous alliance, Festuca rubra herbaceous alliance, Festuca rubra intermittently flooded herbaceous alliance
Calveg Wet grasses and forbs, Perennial grasses and forbs
Holland Coastal terrace prairie, Bald Hills prairie, Serpentine bunchgrass
Munz Coastal prairie
WHR Perennial grassland
CDFW CA Code 41.251.00

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 Vancouverian Lowland Grassland and Shrubland
Group Vancouverian coastal grassland