Crimson King Maple, Purple-leaf Norway Maple
Kingdom: Plantae, Division: Magnoliophyta, Class: Magnoliopsida, Order: Sapindales, Family: Sapindaceae, Genus: Acer, Species: Acer platanoides · Sapindaceae (Soapberry/Maple family) · Simple, Deciduous
Species
Acer platanoide 'Crimson King'
Leaf Type
Simple, Deciduous
Family
Sapindaceae (Soapberry/Maple family)
Shape
Palmately lobed, typically with 5 lobes featuring sharp, pointed tips (acuminate)
Size
Large; approximately 5-7 inches in length and width, which is standard for a mature specimen of this cultivar.
Margin
Sparse, sharp teeth along the edges of the lobes; otherwise mostly entire between the points.
Arrangement
Opposite; leaves are positioned in pairs directly across from one another on the stem.
Rarity
Very Common; one of the most frequently planted ornamental shade trees in North America and Europe.
Color & Pattern
Deep maroon to dark reddish-purple (almost black) on the upper surface; dark green undertones suggest slight light-driven fading. Veins and petiole are a matching deep burgundy.
Venation Pattern
Palmate; several main veins radiate from the base where the leaf meets the petiole.
Texture & Surface
Smooth (glabrous) and somewhat leathery; the surface has a slight waxy sheen.
Description
A medium-sized deciduous tree reaching 40-50 feet. It is famous for its dense, symmetrical oval crown and striking purple foliage that lasts all summer, unlike other maples that turn green. The bark is gray-brown with vertical furrows, and it produces yellow-maroon flowers in early spring.
Key Features
Milky sap exuded from broken petioles, deep purple summer color, and wide-spreading samaras (winged seeds) with an angle of nearly 180 degrees.
Habitat
Widely cultivated in urban and suburban landscapes; prefers well-drained soil in full sun to maintain its deep color.
Geographic Range
Species native to Europe and Western Asia; 'Crimson King' is a popular ornamental cultivar grown globally in temperate zones.
Condition Notes
Fair to Good; shows some physical tearing and insect herbivory (small holes) near the center. Slight bronzing at the edges suggests late-season exposure.
Interesting Facts
The 'Crimson King' cultivar was selected in Belgium in the 1930s. It is so successful that in some regions, the parent species (Norway Maple) is considered invasive due to its heavy seed production and dense shade.
Medicinal & Uses
Primarily ornamental; used for shade and aesthetic appeal in landscaping. The wood is hard but less valued than Sugar Maple. Sap contains sugar but is rarely tapped commercially.
Ecological Role
Provides heavy shade which can inhibit ground-level biodiversity. Its seeds are eaten by squirrels and birds, but it is often criticized for outcompeting native woodland species.
Similar Species
Acer platanoides 'Schwedleri' (which turns green by mid-summer) and Acer palmatum (Japanese Maple, which usually has more deeply divided lobes).
Foraging Tips
Identify in summer by the unmistakable dark purple foliage. To confirm it is a Norway Maple vs. a Sycamore Maple, break a leaf stem; a Norway Maple will produce a droplet of milky white latex.
Toxicity Warning
Generally non-toxic to humans. Note: The leaves are reported to be toxic to horses if consumed in large quantities, potentially causing laminitis.