Fall Color Series: Acer grandidentatum

November 15, 2019

Next on our Fall Color spotlight: Acer grandidentatum!


Native to the Western United States and regions of Northern Mexico, Acer grandidentatum is a close relative to the Sugar Maple – often referred to as Western Sugar Maple, Bigtooth, or Canyon Maple. The genus Acer comes directly from Latin language, literally translating to “maple tree,” while the specific epithet grandidentatum means having large teeth, in reference to the deeply toothed foliage.

C.Maylett [CC-BY-SA-3.0-migrated]

The Bigtooth Maple has a spotty distribution, and may be found dappled across southeastern Idaho, south-central Montana, western Wyoming, south to Arizona, New Mexico, south-central Texas, and into northern Mexico. Historically it has been tapped and its sap has been harvested for syrup production – today North America is the largest producer of maple syrup, harvesting around 10,000,000 gallons every year!

Steve Hurst @ USDA-NRCS PLANTS Database [Public domain]

In its native landscape, Bigtooth Maple prefers sites in canyons, ravines, on mountainsides and slopes, and along mountain streams. It is slow growing to 25′-40’ tall, although the overall mature size and structure of the tree varies with access to moisture in the soil; in areas of high moisture it may be found as a single or multi-trunked tree, while in drier areas with limited access to water, Bigtooth Maple may present itself as a shrub. The striking pigmentation that Bigtooth Maple takes on during fall outshines any other Acer! Here at the nursery we carry Acer grandidentatum ‘Schmidt’ – more commonly known as the Rocky Mountain Glow Maple.

This tree is highly unique, because it is Acer grandidentatum grafted onto the rootstock of Acer saccharum. First introduced by J. Frank Schmidt Nurseries, Rocky Mountain Glow maple grows to be smaller and more compact than typical Acer saccharum. The leaves of the Rocky Mountain Glow Maple resemble that of the Sugar Maple but are much smaller in size. Throughout Spring and Summer, they maintain their dark emerald green coloration, and non-showy flowers lead to the production of winged samaras. Arrival of fall ignites a fiery show of yellows, golds, oranges, and reds that give the tree’s canopy a glowing aura.

Acer grandidentatum ‘Rocky Mountain Glow’ fall color-

C.Maylett [CC-BY-SA-3.0-migrated]

In the cultivated landscape, Rocky Mountain Glow Maple slowly grows to reach 15′ – 25’ tall, with a spreading canopy to about 15’. Issues and pests concerning the Rocky Mountain Glow Maple are minimal, but include chlorosis (chlorosis: a yellowing of the leaves due to a lack of chlorophyll) and sunscald. Preferential to moist, well-drained soil and moderate to full sun, this tree will do well as a stand-alone specimen or in a grouping to build a vegetative privacy screen. Avoid planting Rocky Mountain Glow on streets, because of the overall mature size of the tree and susceptibility to soil compaction.


Companion plants for Acer grandidentatum: Berberis (Barberry), Cornus (Dogwood), Hemerocallis (Daylily), Ligustrum (Privet), Potentilla (Potentilla), Weigela (Weigela)



“Acer grandidentatum.” USDA Fire Effects Information Systems. https://www.fs.fed.us/database/feis/plants/tree/acegra/all.html#BOTANICAL%20AND%20ECOLOGICAL%20CHARACTERISTICS.

“Acer saccharum subsp. grandidentatum.” Missouri Botanical Garden. http://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?taxonid=241814.

Perry, Nick. “Featured Tree: Rocky Mountain Glow Maple (Acer grandidentatum ‘Schmidt’.” University of Minnesota – UFore Nursery & Lab. https://trees.umn.edu/news/featured-tree-rocky-mountain-glow-maple-acer-grandidentatum-%E2%80%98schmidt%E2%80%99.

“Top Regions Producers of Maple Syrup.” Maple Syrup World. https://www.maplesyrupworld.com/pages/Top-Regions-Producers-of-Maple-Syrup.html.