Norway maple
Common name: Norway maple
Scientific name: Acer platanoides L.
Synonyms: 'Crimson King', 'Columnare', 'Erectum', 'Olmsted', 'Drummondii', 'Emerald Queen', 'Globosum', 'Schewedleri', and 'Summershade', and any other cultivar capable of producing viable seed.
Legal status: Specially Regulated with the requirement that sellers affix a label that advises: "Norway maple should only be planted in areas where the seedlings will be controlled or eradicated by mowing or other means. Norway maple seed is wind dispersed so trees should not be planted closer than 100 yards from natural areas."
Life cycle: Perennial
Related species: Sugar maple, red maple, silver maple, black maple, mountain maple; non-native ornamental maples
Habitat: Adaptable to many growing conditions. Grows in full sun or shade. Found naturalizing in forests, particularly within disturbed understory.
Impact: Environmental, very shade tolerant, forms dense canopy, reduces native plant diversity in understory.
Native range: Central and eastern Europe and western Asia
Means of spread: Plants reproduce by seed which can be spread by wind and water.
Background
The first documented Norway maple introduction to North America was in 1756. It has naturalized in Great Britain, the northeastern United States, and southeastern Canada. Norway maple is widely planted as a shade tree in urban areas because it can tolerate drought, deicing salt, compacted soils, and air pollution. Norway maple has many cultivars with distinct forms including columnar, and weeping varieties. Another distinct characteristic is the green to burgundy range in leaf color.
Identification
Norway maple is a large shade tree usually growing 40-60 feet tall but can grow up to 90 feet or more. Branching is opposite. Young bark is olive to light brown and becomes gray and furrowed with age. Naturalizing Norway maple could be confused with the native sugar maple. Key characteristics to distinguish from the native sugar maple are the angle of the samara, width of leaves, and white sap of leaves, petioles, and twigs (see photos).
Management
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Mechanical: Pulling or digging up roots
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Chemical: Foliar, cut stump, hack and squirt, basal bark herbicide treatment
Images and their description
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Characteristics described |
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Norway maple as a large shade tree. |
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Leaves have 5-7 lobes, often wider than long. Cultivars can be purple.
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Gray furrowed bark of older tree. |
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Fruit is a double samara, at obtuse angle. (All native maples are <90 degrees.)
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Seedling with cotyledons. |
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Norway maple seedling with first true leaves. |
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Norway maple infestation. |
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Broken petioles exude white sap. |
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Notable characteristics of Norway maple. |