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Rocky Mountain Maple
Acer glabrum Torry
Reported by Lewis and Clark Expediton at the Lemhi River on 13 Aug 1805.
Rocky Mountain maple is a native, deciduous tall shrub or small tree. It often grows 20 to 30 feet tall, with crown widths from 10 to 20 feet (3-6 m) wide and a stem diameter up to 12 inches, though it can reach 40 feet tall, and 2 feet (0.6 m) in diameter. Rocky Mountain maple is usually tall and spindly in closed stands, with a more dense and brushy growth form in open stands. Though it may have a single dominant stem, Rocky Mountain maple most often occurs as a multi-stemmed shrub 5 to 6.5 feet tall.
Rocky Mountain maple has opposite, ascending to erect branches, rounded twigs, and a narrow crown. The bark of Rocky mountain maple is smooth until maturity, when fissures develop. Rocky mountain maple has a wide, spreading root system with a combination of deep and lateral woody roots . It may be monoecious, or dioecious. Flowers are borne in loose terminal cymes arising from lateral buds and grow in drooping clusters. The paired seeds are winged samaras. Seeds are 0.16 to 0.2 inch long and samaras are 0.08 to 0.12 inch long..
Rocky Mountain maple occurs on wetlands, stream banks, canyons, and upland mountain slopes Though it occurs on both moist and dry sites. Rocky Mountain maple is more closely tied to drainages in arid zones of its distribution, but occurs on drier exposures northward and at higher elevations. On upland sites, Rocky Mountain maple grows on lower, mid, and upper slopes , alluvial terraces, summits, ridge tops, snow chutes, and talus slopes. (Source)Medicinal Uses: A bark decoction was used as a poison antidote.
Other Uses: Maples generally have a good, strong and pliable wood. The rocky mountain maple's wood was widely used by the native peoples of the central west coast of North America. It was used for making miniature paddles that served as rattles on ceremonial costumes. It was also used for making drying racks, drum hoops, snowshoes, spears, pegs, toys and masks. Women used it to make their sweathouses because it is easy to bend and for the same reason it was also often used to make a child’s first bow. The fibrous bark was woven into mats and into rope.
Value to Animals:
Ruffed grouse in Idaho eat the leaves and buds of Rocky Mountain maple . Rocky Mountain maple seeds are also important forage for grosbeaks and small mammals.
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