Native to Europe, this maple has an unusually symmetrical, dense crown. Due to their high shade, drought, and air pollution tolerances, as well as their shallow root system, these are considered invasive and are pushing out other native species. However, ‘Crimson King’ is still planted commonly due to its magnificent foliage. The leaves are somewhere between a maroon and purple and appear exceptionally striking.
Acer platanoides (Norway Maple)
Hardiness Zones: 3-7 (survives, but will not thrive, in zone 7)
Height: 9-15 meters (30-50 feet) tall (capable of reaching 28 meters (90 feet) tall)
Diameter: 6-12 meters (20-40 feet) across
Growth Rate: rapid (at first), slows down with age
Age: up to 150 years
Root System: shallow, remains mostly at the surface
Subspecies: ‘Crimson King’ (has maroon-purplish foliage, slower growth rates), ‘Emerald Queen’ (has deep green foliage), ‘Deborah’
(changes from bright red to dark green leaves, changing to orange-bronze in autumn), ‘Schwedleri’, ‘Globosum’ (dwarf), ‘Summershade’ (more resistant to heat), ‘Columnare’/’Erectum’/’Olmsted’ (columnar, vertical growth)
Tolerates: drought, pollution (poor air quality), shade, typically pest resistant
Problems (major): Verticillium may kill off an entire tree.
Problems (minor): The bark may succumb to sunscald in the summer and frost cracks (radial shakes) in winter, especially on younger trees. Leaf scorch may harm some trees receiving too much light (mostly in the summer). Leaf hoppers can be a problem if not noticed soon. Bark splits relatively frequently. Norway Maples are apparently reducing Sugar Maple populations due to competition. The shallow roots sometimes
cause complications. Dense shade and some toxins, created by older trees especially, crowds out other plants.
Poisonous: Pushes out other native species by producing toxic chemicals. These are not known to be poisonous to horses, although Acer rubum (Red Maple) has foliage that is.
Soil requirements: “average” (not picky about certain soil types), well-drained soils
Air requirements: tolerant of urban conditions and poor air quality
Watering requirement: medium
Sun requirement: full sun or part-shade
Cones (male): none
Cones (female): none
Leaves: have 5 sharply pointed lobes, up to 15 centimeters (7 inches) across
Flowers: Maroon-yellow flowers occur in early spring in clusters known as “corymbs”.
Fruits: 2 inch long, purplish-red samaras occur in pairs connected at their bases (the non-winged areas)
Seeds require stratification: yes
Monoecious or Dioecious: dioecious (separate male and female trees)
The petioles (“leaf stems”) release a milky-textured sap. The gray-colored bark has splothces of black and shallow bark furrows. These trees are native to Europe.
Shade tree, be careful for their shallow root systems, however. Variety ‘Crimson King’ has exceptional foliage.
A. platanoides foliage and samaras (seeds) of ‘Emerald Queen’
A. platanoides flowers and foliage
The three (3) images provided were taken by me during the summer of 2013. They may be used for informational and educational purposes, as long as this article or online journal is appropriately cited.