Avena (barbata, fatua) Herbaceous Semi-Natural Alliance
Wild oats grasslands

USDA Ecological Section Map

Summary Information

  • Primary Life FormHerb
  • Elevation10-1200 m
  • State RarityNone
  • Global RarityNone
  • DistributionUSA: CA, OR?
  • Endemic to CaliforniaNo
  • Invasive species rank See remarks
  • Endemic to California Floristic Province and DesertsNo
  • Date Added2009/09/01

Characteristic Species

Avena barbata and/or Avena fatua is dominant or co-dominant in the herbaceous layer. Emergent trees and shrubs may be present at low cover.

Vegetation Layers

Herbs < 1.2 m; cover is open to continuous.

Membership Rules

  • Avena fatua > 50% relative cover, and native herbs relatively low in cover in the herbaceous layer (Keeler-Wolf and Evens 2006).
  • Avena spp. > 50% relative cover, and native herbs < 10% relative cover in the herbaceous layer (Evens and Kentner 2006, Klein et al. 2007).
  • Avena spp. > 75% relative cover; other non-native or native plants < 5% absolute cover, if present, in the herbaceous layer (Evens and San 2004).


Waste places, rangelands, openings in woodlands.

Other Habitat, Alliance and Community Groupings

MCV (1995) California annual grassland series
NVCS (2009) Avena fatua herbaceous alliance
Calveg Annual grasses and forbs, Non-native/ornamental grass
Holland Valley and foothill grassland, Non-native grassland
Munz Valley grassland
WHR Annual grassland
CDFW CA Code 44.150.00

National Vegetation Classification Hierarchy

Formation Class Mesomorphic Shrub and Herb Vegetation (Shrubland and Grassland)
Formation Subclass Mediterranean Scrub and Grassland
Formation Mediterranean Grassland and Forb Meadow
Division California Grassland and Meadow
Macro Group California Annual and Perennial Grassland
Group Mediterranean California naturalized annual and perennial grassland