Arbutus menziesii Forest Alliance
Madrone forest

USDA Ecological Section Map

Summary Information

  • Primary Life FormTree
  • Elevation100-1400 m
  • State RarityS3.2
  • Global RarityG4
  • DistributionCAN: BC. USA: CA, OR, WA(USDA Plants)
  • Endemic to CaliforniaNo
  • Endemic to California Floristic Province and DesertsNo
  • Date Added2009/09/01

Characteristic Species

Arbutus menziesii is dominant or co-dominant in the tree canopy with Acer macrophyllum, Notholithocarpus densiflorus, Pseudotsuga menziesii, Quercus agrifolia, Quercus chrysolepis, Quercus kelloggii, Quercus wislizeni and Umbellularia californica.

Vegetation Layers

Trees < 40 m; canopy is continuous. Shrub layer is sparse to intermittent. Herbaceous layer is sparse.

Membership Rules

  • Arbutus menziesii > 50% relative cover in tree canopy (Evens and Kentner 2006).


Stream terraces and upland slopes with productive soils or steep slopes with shallow, rocky, infertile soils.

Other Habitat, Alliance and Community Groupings

MCV (1995) Tanoak series
NVCS (2009) Not treated
Calveg Pacific madrone, Tanoak
Holland Mixed evergreen forest
Munz Mixed evergreen forest
WHR Coastal oak woodland
CDFW CA Code 73.200.00

National Vegetation Classification Hierarchy

Formation Class Mesomorphic Tree Vegetation (Forest and Woodland)
Formation Subclass Temperate Forest
Formation Cool Temperate Forest
Division Western North America Cool Temperate Forest
Macro Group Californian-Vancouverian Montane and Foothill Forest
Group Vancouverian evergreen broadleaf and mixed forest