Acer glabrum
Native to western North America, this broadleaf maple is valued for wildlife habitat and slope stabilization, features striking red bark and crimson autumn foliage, tolerates shade to sun on moist montane sites, often forms a small to medium multi-stemmed tree with a deep root system that helps stabilize soil, and produces winged seeds suited to wind dispersal.
Common Names
Rocky Mountain Maple, Douglas Maple, New Mexico Maple, Rock Maple, Mountain Maple, Greene's Maple, Torrey Maple, Dwarf Maple, California Mountain Maple, Sierra Maple
Summary
Rocky Mountain Maple is a western North American deciduous shrub or small tree, typically 12–30 ft tall with a multi‑stem or single‑trunk form and smooth gray bark when young; leaves are palmately lobed (3–5 lobes), flowers are greenish‑yellow in spring, and fruits are winged samaras, with autumn color ranging from yellow to red and habitat along stream banks and moist sites in conifer forests.
Preferring moist, well‑drained soils, it grows best in full sun to part shade and tolerates sandy, loamy, and heavy clay soils with moderate drought tolerance once established; irrigation may be needed in hot, dry periods. It provides erosion control and woodland‑garden value as an understory tree, supports wildlife (browse for moose, elk, and deer; nectar for native bees), and features wind‑dispersed seeds and root‑crown sprouting after disturbance; seeds require chilling to germinate, and nursery stock is available; prune in summer after leaf development to avoid sap bleed; hardiness zones 3a–8b.
Lifecycle
Perennial
Height
12-30 feet
Spread
10-20 ft
Hardiness Zones
Zones 4–8
Sunlight Requirements
Ideally full sun, tolerates partial sun to partial shade.
Soil Type
Loamy, well-drained soil
Soil Drainage
Moist, well-drained soils.
Soil pH
5.8–7.5, slightly acidic to neutral, tolerates moderate alkalinity
Bloom Color
Insignificant
Bloom Time
Spring (April–June, varies by elevation)
Foliage Color
Green
Fall Foliage Color
Yellow, orange and red
Leaf Lifecycle
Deciduous
Growth Rate
Moderate; 1-2 ft per year
Seasons of Interest
Spring and Fall
Propagation Methods
Seeds, Cuttings, Layering, Micropropagation, Root crown sprouts/suckers
Attracts Wildlife
Bees, butterflies, other pollinators, and birds are attracted
Taxonomy
- Taxonomic Rank
- Species
- Author
- Pursh
Superior Taxa
- Kingdom
- Plantae
- Subkingdom
- Pteridobiotina
- Phylum
- Angiosperms
- Order
- Sapindales
- Family
- Sapindaceae
- Subfamily
- Hippocastanoideae
- Genus
- Acer