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Douglasii

Acer glabrum (AY-ser GLAH-brum)

Family: Sapindaceae Native Understory (15-40 ft)

Rocky Mountain maple is a deciduous shrub or small shade tree in the maple family (Sapindaceae) and is native to western North America from Alaska south to California and west to Nebraska and south to New Mexico. The specific epithet means smooth, without hair, referring to its smooth stems and leaves. The species is named after David Douglas, a Scottish botanist who in addition to this tree, is also known for the Douglas fir. This tree will grow 12-30 feet in height and spread 10 to 20 feet wide. It usually has a multi-trunk habit and a shrub-like growth and a narrow crown in more open areas. It can be tall and spindly in closer stands of trees. Can withstand sandy, loamy, and heavy clay acidic soils, prefers well-drained soil and needs lots of organic matter. It performs best in semi-shade to shade. Plant in a location sheltered from strong winds, frost, and afternoon sun. This is a relatively low-maintenance tree, and should only be pruned in summer after the leaves have fully developed, as it may 'bleed' sap if pruned in late winter or early spring. There are four varieties with distinct distributions. They are listed below. It is primarily grown for its ornamental red fruit in the late summer and fall and its interesting red twigs that stand out, particularly in the winter. The fall color is knock-out yellow-to-red. Works well for erosion control, in a woodland garden and as an understory tree. Best grown in its native habitat and would not be appropriate for the southeast. Insects, Diseases, and Other Plant Problems: No significant insect or disease problems. In alkaline soils, it can develop manganese chlorosis. Watch for aphids, leafhoppers, borers, scale, and caterpillars. Also note that verticillium wilt attacks the vascular system and can be fatal. Canker, fungal leaf spot, and root rots may also occur. Wind and ice may break some branches. The Clemson Cooperative Extension Home and Garden Information Center has a factsheet on common maple diseases and insect pests. More information on Acer .

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 61 attributes.

How it fits the guild

Guild layer 2 - Understory (15-40 ft) Optimal soil pH Acid (<6.0)
See companions & conflicts ↓

Companions & Conflicts

Curated pairwise relationships between this plant and others in the library — who feeds whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.

No curated interactions recorded for this species yet.

Also noted by NC State

Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.

Often confused with Acer rubrum
Fills a similar niche Quercus nigra Ulmus alata Ulmus americana
Native alternatives Acer rubrum

Full plant profile

Growing Conditions
Plant type
Shrub; Tree
Life cycle
Woody
USDA zones
3a, 3b, 4a, 4b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b
Light
Dappled Sunlight (Shade through upper canopy all day) | Full sun (6 or more hours of direct sunlight a day) | Partial Shade (Direct sunlight only part of the day, 2-6 hours)
Soil texture
Clay; High Organic Matter; Loam (Silt); Sand
Soil pH
Acid (<6.0)
Soil drainage
Good Drainage | Moist | Occasionally Dry | Very Dry
Mature size
Height: 12 ft. 0 in. - 30 ft. 0 in. | Width: 10 ft. 0 in. - 20 ft. 0 in.
Growth rate
Rapid
Maintenance
Low
Canopy layer
2 - Understory (15-40 ft)
Form & Appearance
Habit / form
Erect; Multi-trunked; Rounded; Spreading
Texture
Medium
Foliage
Deciduous
Leaf color
Gold/Yellow; Green; Pink; Red/Burgundy
Leaf margin
Lobed
Leaf size
1-3 inches wide
Hairs present
No
Leaf detail
Lobed leaves green most of the year turn yellow to brick red in the fall.
Fall color
Gold/Yellow; Red/Burgundy
Flower color
Green
Flower value
Fragrant
Flower form
Cyme; Insignificant
Flower size
< 1 inch
Flower detail
Green, insignificant flowers in April in terminal drooping cymes. The flowers are dioecious (individual flowers are either male or female, but only one sex is to be found on any one plant so both male and female plants must be grown for pollination to occur.
Bloom time
Spring
Fruit color
Brown/Copper; Green; Pink; Red/Burgundy
Fruit type
Samara
Fruit size
< 1 inch long
Fruit detail
Red winged samaras. This plant has green, insignificant flowers in April, which are pollinated by insects and followed by showy red winged samaras in late summer. Plant is dioecious.
Bark color
Dark Brown; Dark Gray; Light Brown; Light Gray
Bark detail
Smooth, brownish gray bark becomes fissured with age
Stem color
Red/Burgundy
Stem detail
The stems are smooth and red in winter.
Wildlife & Ecology
Native status
Native
Origin
Western North America
Distribution
Alaska, Alberta, Arizona, British Columbia, California, Colorado, Idaho, Mexico Northeast, Montana, Nebraska, Nevada, New Mexico, Oregon, South Dakota, Utah, Washington, Wyoming, Yukon
Wildlife value
Members of the genus Acer support Imperial Moth (Eacles imperialis) larvae which have one brood per season and appear from April-October in the south. Adult Imperial Moths do not feed. Food and shelter to wildlife
Attracts
Butterflies; Moths; Pollinators; Small Mammals; Songbirds
Play value
Attracts Pollinators; Pieces Used in Games; Wildlife Cover/Habitat; Wildlife Food Source; Wildlife Nesting
Food & Medicine
Harvest time
Fall; Summer
Fruit type
Samara
Landscape Use
Landscape location
Slope/Bank; Woodland
Landscape theme
Butterfly Garden; Children's Garden; Nighttime Garden; Pollinator Garden; Shade Garden; Winter Garden
Design feature
Shade Tree; Understory Tree
Garden tags
#shade garden #small tree #low maintenance #deciduous #winter interest #fall interest #shade tree #erosion control #children's garden #red fruits #small mammals #red stems #multitrunked #clay soils tolerant #fast growing #bird friendly #butterfly friendly #imperial moth #larval host plant #nighttime garden #samaras #fall color yellow #fall color red #pollinator plant #wildlife friendly #woodland #winter cover #nesting site
Problems & Resistance
Insect problems
Common Insect Pests of Maple in North Carolina
Disease problems
Common Disease Pests of Maple in North Carolina
Resistant to
Diseases; Erosion; Insect Pests
Particularly resistant to
erosion
Propagation
Seed

Planted at Hunnicutt

Nobody’s planted this one yet.