Vine Maple: Acer circinatum - Normally a species occurring west of the eastern foothills of the Cascades, this species extends a little farther east in the Simcoe and Wenatchee Mountains.
Douglas Maple: Acer glabrum var. diffusum - This species possibly comes into the region in extreme southeastern Oregon?
Douglas Maple, Rocky Mountain Maple: Acer glabrum var. douglasii (Synonyms: Acer douglasii, Acer glabrum ssp. douglasii) -
Rocky Mountain Maple: Acer glabrum var. glabrum (Synonyms: Acer glabrum var. greenei, Acer glabrum var. torreyi) - Extends west across Idaho to extreme eastern Oregon.
Bigleaf Maple, Oregon Maple: Acer macrophyllum - Primarily a species of the west of the Cascades (below 4000'), this can be found occasionally on the east Cascade slopes and east in the Columbia River Gorge to The Dalles, OR.
Box Elder: Acer negundo (Synonyms: Acer negundo ssp. californicum, Acer negundo var. californicum, Acer negundo var. negundo, Acer negundo var. variegatum, Negundo aceroides, Negundo californicum, Negundo negundo) - Introduced from eastern USA. Occasional escapee, especially along water courses.
Norway Maple: Acer platanoides (Synonym: Acer platanoides var. schwedleri) - Introduced species from Europe. Occasional escape to the wild.
Sycamore Maple: Acer pseudoplatanus - Introduced species. Rare escape to the wild.
Silver Maple: Acer saccharinum (Synonyms: Acer dasycarpum, Acer saccharinum var. laciniatum, Acer saccharinum var. wieri, Argentacer saccharinum) - Introduced from other regions of North America.
Sugar Maple: Acer saccharum -Non native. Occasionally utilized in domestic landscapes east of the Cascades.