Location: This small specimen may be found in the southernmost of three planter plots on the east end of the Anderson Hall courtyard.

Summary: A glance at this specimen makes one wonder, is this even a tree? This is a fair thought, as the spindly shrub-like specimen here is quite small and certainly does not strike the imagination in the same way that the coniferous giants of our region do. This species does in fact grow to a respectable stature of up to 30’ in some portions of its range. However, here in Washington is it most often dwarfed due to its status as an understory species, eking out a living in the shade of larger cousins. The species is generally more drought-tolerant than its close relative the Vine Maple, which is likewise a small understory example of the Acer genus. This trait means that Rocky Mountain Maples are more often found growing in forests in the rain shadow side of mountains, such as on the San Juan Islands and the east side of the Cascades. Their leaves further distinguish them from the Vine Maple, bearing three to five lobes rather than seven to nine. The bark of this tree is a traditional source of utensil and toolmaking material for Indigenous Nations in the region, and its pliable wood makes it, along with Vine Maple, a prime wood for the creation of snowshoes and other frames. 

As of this publication, this specimen is the only Rocky Mountain Maple on the UW Campus. Note that the original trunk of this tree was cut, and the current branches regrew from the old stump. This ability to resprout from the roots is highly useful for an understory species who cannot expect to simply ride out disturbances by being big and tall. While fires may burn beneath the high branches of a Douglas-fir without ever touching a living leaf, flames will certainly catch a species as low to the ground as our maple, who survives the burn by using stored energy in its roots to rise from the ashes in the years after the burn has passed. Maple trees are forage beloved of ungulates, and the fresh spring leaves and flowers are edible for our species as well.

Identifying Features light: The Rocky Mountain Maple is a smaller tree, much like its cousin the Vine Maple. It is, however, far less frequently seen inhabiting the understory of our state's forests, although it has a much wider range, growing south all the way into California and Arizona. There it is a beautiful addition to the forest, its distinctly palmate leaves with far sharper serrations and lobes than either of our other two native maples. Bright green in the summer, those leaves fade to a beautiful orangish red in fall. Fresh stems are often a red hue, and the bark as it ages turns gray and fissured. The grand beauty of this species is not matched by stature, and it seldom exceeds 30 feet in height.

Identifying Features In Depth:

1. Form: A small tree usually with low apical control and multiple trunks, spreading into slender upright branches. Generally only grows to 30 ft (9m) in height and about a foot (0.3m) in diameter.

2. Leaves: The leaves of this species grow in an opposite pattern, 1.4-4.5in (4-11cm) in length and width (although they can be far smaller). They have 3 or 5 pointed lobes, each ringed with smaller sharp serrations and a palmate venation pattern with a reddish leafstalk. They are shiny dark green above and pale below. In autumn they usually turn bright red to orange. 

3. Bark: The bark of these trees is gray or brown, thin and smooth on younger trees (more fissured on old trunks). The twigs are often a reddish brown color and slender.

4. Reproductive Bodies: Male and female flowers usually occur on separate trees (they are monoecious), and are about 6mm wide with 4 petals on drooping stalks in branched clusters. The fruit, the ubiquitous samara of the whole maple family, are paired and forked, creating the “helicopters” which spin to the ground in circles. They mature in late summer or early autumn.

Historical Background: A flexible and often densely growing tree, the Rocky Mountain maple has been employed by indigenous peoples of the Pacific northwest to build scoop nets with which salmon may be wrested from the rivers and streams of the region. Here in Washington, this tree, sometimes called the dwarf maple, shines, growing to as much as 40ft in height, impressive given that in some regions it creeps upon the ground like a vine. Like with the vine maple, indigenous tribes determined that the hard flexible wood is optimal for construction of snowshoe frames, as well as for bows. The Salish peoples carve miniature paddles to line ceremonial costumes, and the Saanich of Vancouver Island have used the bark as an antidote for poison. A small tree, it is considered a pest by many in the lumber industry and not generally seen as commercially valuable. The tree is however valuable as winter forage for wild herbivores, deer and elk often eating the low stems as winter forage and even breaking trunks to get to new growth above their reach. 

Native Range: These trees prefer moist soils especially in forested mountain slopes. They grow from near the Mexican border up to southeast Alaska and in both the Rocky Mountains and Sierra and Cascade mountains. It is the furthest north reaching maple in the new world. Near sea level in the north it prefers 5000-9000 ft (1524-2743) elevations in the south.