Acer macrophyllum Forest & Woodland Alliance
Bigleaf maple forest and woodland

USDA Ecological Section Map

Summary Information

  • Primary Life FormTree
  • Elevation0-1400 m
  • State RarityS3
  • Global RarityG4
  • DistributionCAN: BC. USA: CA, OR, WA (NatureServe)
  • Endemic to CaliforniaNo
  • Endemic to California Floristic Province and DesertsNo
  • Date Added2009/09/01

Characteristic Species

Acer macrophyllum is dominant or co-dominant in the tree canopy with Abies concolor, Alnus rhombifolia, Alnus rubra, Calocedrus decurrens, Cornus nuttallii, Picea sitchensis, Pseudotsuga menziesii, Quercus chrysolepis, Quercus kelloggii, Quercus lobata, Sequoia sempervirens, Taxus brevifolia and Umbellularia californica.

Vegetation Layers

Trees < 75 m; canopy is intermittent to continuous; it may be two-tiered. Shrub layer is infrequent or well-developed. Herbaceous layer is sparse or abundant.

Membership Rules

  • Acer macrophyllum > 25% relative cover in the tree canopy (NatureServe 2007).
  • Acer macrophyllum > 5% absolute cover in the tree canopy (Jimerson et al. 1996) and usually > 30% relative cover.


Raised stream benches, terraces, and lower slopes with seeps. Soils may be rocky. The USFWS Wetland Inventory (1996 national list) recognizes Acer macrophyllum as a FAC plant.

Other Habitat, Alliance and Community Groupings

MCV (1995) Douglas fir series
NVCS (2009) Acer macrophyllum forest alliance, Acer macrophyllum seasonally flooded forest alliance, Pseudotsuga menziesii-Acer macrophyllum forest alliance
Calveg Pacific Douglas-fir, Coastal mixed hardwood, Interior mixed hardwood, Bigleaf maple, Montane mixed hardwood
Holland North Coast riparian forests, Central Coast riparian forest, Douglas-fir forest, Coast range mixed coniferous forest
Munz Douglas fir forest, North Coast coniferous forest
WHR Douglas fir, Montane hardwood-conifer
CDFW CA Code 61.450.00

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 Upland Vancouverian mixed woodland and forest