Hubbry Logo
Acer platanoidesAcer platanoidesMain
Open search
Acer platanoides
Community hub
Acer platanoides
logo
8 pages, 0 posts
0 subscribers
Be the first to start a discussion here.
Be the first to start a discussion here.
Acer platanoides
Acer platanoides
Acer platanoides
View on Wikipedia
from Wikipedia

Norway maple
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Sapindales
Family: Sapindaceae
Genus: Acer
Section: Acer sect. Platanoidea
Species:
A. platanoides
Binomial name
Acer platanoides
Distribution map (native habitat)
Synonyms
List
  • Acer cappadocicum subsp. turkestanicum (Pax) A.E.Murray
  • Acer dieckii (Pax) Pax
  • Acer dieckii f. integrilobum Schwer.
  • Acer dieckii f. monstrosum Schwer.
  • Acer fallax Pax
  • Acer laciniatum Borkh. ex Tratt.
  • Acer lactescens Pers.
  • Acer laetum var. cordifolium R.Uechtr. & Sint.
  • Acer lobelii var. dieckii Pax
  • Acer lobergii Dippel
  • Acer palmatifidum Tausch ex Steud.
  • Acer platanifolium Stokes
  • Acer reitenbachii Dippel
  • Acer rotundum Dulac
  • Acer schwedleri K.Koch
  • Acer vitifolium Opiz ex Tausch.
  • Euacer acutifolium Opiz
  • Euacer platanoides (L.) Opiz
  • Acer lipskyi Rehder ex Lipsky
  • Acer pseudolaetum Radde-Fom.
  • Acer turkestanicum Pax

Acer platanoides, commonly known as the Norway maple, is a species of maple native to eastern and central Europe and western Asia, from Spain east to Russia, north to southern Scandinavia and southeast to northern Iran.[2][3][4] It was introduced to North America in the mid-1700s as a shade tree.[5] It is a member of the family Sapindaceae.

Description

[edit]

Acer platanoides is a deciduous tree, growing to 20–30 m (65–100 ft) tall with a trunk up to 1.5 m (5 ft) in diameter, and a broad, rounded crown. The bark is grey-brown and shallowly grooved. Unlike many other maples, mature trees do not tend to develop a shaggy bark. The shoots are green at first, soon becoming pale brown. The winter buds are shiny red-brown.

The leaves are opposite, palmately lobed with five lobes, 7–14 cm (2+3⁄4–5+1⁄2 in) long and 8–25 cm (3+1⁄4–9+3⁄4 in) across; the lobes each bear one to three side teeth, and an otherwise smooth margin.[citation needed] The leaf petiole is 8–20 cm (3+1⁄4–7+3⁄4 in) long, and secretes a milky juice when broken. The autumn colour is usually yellow, occasionally orange-red.[6][7][8]

Flower, close-up

The flowers are in corymbs of 15–30 together, yellow to yellow-green with five sepals and five petals 3–4 mm (1⁄8–3⁄16 in) long; flowering occurs in early spring before the new leaves emerge. The fruit is a double samara with two winged seeds. the seeds are disc-shaped, strongly flattened, 10–15 mm (3⁄8–5⁄8 in) across and 3 mm (1⁄8 in) thick. The wings are 3–5 cm (1+1⁄4–2 in) long, widely spread, approaching a 180° angle. It typically produces a large quantity of viable seeds.

Under ideal conditions in its native range, Norway maple may live up to 250 years, but often has a much shorter life expectancy; in North America, for example, sometimes only 60 years. Especially when used on streets, it can have insufficient space for its root network and is prone to the roots wrapping around themselves, girdling and killing the tree. In addition, their roots tend to be quite shallow and thereby they easily out-compete nearby plants for nutrient uptake.[9] Norway maples often cause significant damage and cleanup costs for municipalities and homeowners when branches break off in storms as they do not have strong wood.[10][11]

  • Leaf, adaxial side
    Leaf, adaxial side
  • Leaf, abaxial side
    Leaf, abaxial side
  • Fruit
    Fruit

Classification and identification

[edit]
Tree in flower
Bark

The Norway maple is a member (and is the type species) of the section Platanoidea Pax, characterised by flattened, disc-shaped seeds and the shoots and leaves containing milky sap. Other related species in this section include Acer campestre (field maple), Acer cappadocicum (Cappadocian maple), Acer lobelii (Lobel's maple), and Acer truncatum (Shandong maple). From the field maple, the Norway maple is distinguished by its larger leaves with pointed, not blunt, lobes, and from the other species by the presence of one or more teeth on all of the lobes.[10][11]

It is also frequently confused with the more distantly related Acer saccharum (sugar maple). The sugar maple is easy to differentiate by clear sap in the petiole (leaf stem); Norway maple petioles have white sap.[citation needed] The tips of the points on Norway maple leaves reduce to a fine "hair", while the tips of the points on sugar maple leaves are, on close inspection, rounded. On mature trees, sugar maple bark is more shaggy, while Norway maple bark has small, often criss-crossing grooves.[citation needed] While the shape and angle of leaf lobes vary somewhat within all maple species, the leaf lobes of Norway maple tend to have a more triangular (acuminate) shape, in contrast to the more finely toothed lobes of sugar maples, that narrow towards the base.[12]: 397  Flowering and seed production begins at ten years of age; however, large quantities of seeds are not produced until the tree is 20. The Norway maple is heterodichogamous—meaning there are both protogynous and protandrous trees (and, more rarely, duodichogamous trees)—and individual trees may change sexual expression from year to year.[13][14]

The fruits of Norway maple are paired samaras with widely diverging wings,[12]: 395  distinguishing them from those of sycamore, Acer pseudoplatanus, which are at 90 degrees to each other.[12] Norway maple seeds are flattened, while those of sugar maple are globose.[citation needed] The sugar maple usually has a brighter orange autumn color, where the Norway maple is usually yellow, although some of the red-leaved cultivars appear more orange.

Norway maple in autumn

The flowers emerge in spring before the leaves and last 2–3 weeks. Leafout of Norway maple occurs roughly when air temperatures reach 55°F (12°C) and there is at least 13 hours of daylight. Leaf drop in autumn is initiated when day lengths fall to approximately 10 hours. Depending on the latitude, leaf drop may vary by as much as three weeks, beginning in the second week of October in Scandinavia and the first week of November in southern Europe. Unlike some other maples that wait for the soil to warm up, A. platanoides seeds require only three months of exposure to temperatures lower than 4 °C (40 °F) and will sprout in early spring, around the same time that leafout begins. Norway maple does not require freezing temperatures for proper growth; however, it is adapted to higher latitudes with long summer days and does not perform well when planted south of the 37th parallel, the approximate southern limit of its range in Europe. Further, most North American Norway maples are believed descended from stock brought from Germany, at approximately 48°N to 54°N, not the more southerly ecotypes found in Italy and the Balkans that evolved for similar lighting conditions as the continental United States. The heavy seed crop and high germination rate contributes to its invasiveness in North America, where it forms dense monotypic stands that choke out native vegetation. The tree is also capable of growing in low lighting conditions within a forest canopy, leafs out earlier than most North American maple species, and its growing season tends to run longer as the lighting conditions of the United States (see above) result in fall dormancy occurring later than it does in the higher latitude of Europe. It is one of the few introduced species that can successfully invade and colonize a virgin forest. By comparison, in its native range, Norway maple is rarely a dominant species and instead occurs mostly as a scattered understory tree.[10][11]

Cultivation and uses

[edit]
Foliage and fruits; the fruit are an important characteristic for identification of this species.

The wood is hard, yellowish-white to pale reddish, with the heartwood not distinct; it is used for furniture and woodturning.[15] Norway maple sits ambiguously between hard and soft maple with a Janka hardness of 1,010 lbf or 4,500 N. The wood is rated as non-durable to perishable in regard to decay resistance.[16] In Europe, it is used for furniture, flooring and musical instruments, especially for violins.

Norway maple has been widely taken into cultivation in other areas, including western Europe northwest of its native range. It grows north of the Arctic Circle at Tromsø, Norway. In North America, it is planted as a street and shade tree as far north as Anchorage, Alaska.[17] In Ontario, it is common in cultivation north to Sault Ste. Marie and Sudbury; although not considered reliably hardy northward, it has been established at Kapuskasing and Iroquois Falls, and even at Moose Factory.[18] It is most recommended in USDA Hardiness Zones 4 to 7 but will grow in warmer zones (at least up to Zone 10) where summer heat is moderate, as along the Pacific coast south to the Los Angeles basin. They tend to prefer wetter Oceanic climates.[19] During the 1950s–60s it became popular as a street tree due to the large-scale loss of American elms from Dutch elm disease.[citation needed]

It is favored due to its tall trunk and tolerance of poor, compacted soils and urban pollution, conditions in which the sugar maple has difficulty. It has become a popular species for bonsai in Europe, and is used for medium to large bonsai sizes and a multitude of styles.[20] Norway maples are not typically cultivated for maple syrup production due to the lower sugar content of the sap compared to sugar maple.[21]

Cultivars

[edit]

Many cultivars have been selected for distinctive leaf shapes or colorations, such as the dark purple of 'Crimson King' and 'Schwedleri', the variegated leaves of 'Drummondii', the light green of 'Emerald Queen', and the deeply divided, feathery leaves of 'Dissectum' and 'Lorbergii'. The purple-foliage cultivars have orange to red autumn colour. 'Columnare' is selected for its narrow upright growth.[11][22] The cultivars 'Crimson King'[23] and 'Prigold' (Princeton Gold)[24] have gained the Royal Horticultural Society's Award of Garden Merit.

As an invasive species in North America

[edit]
Feral Norway maple in Philadelphia.

The Norway maple was introduced to northeastern North America between 1750 and 1760 as an ornamental shade tree. It was brought to the Pacific Northwest in the 1870s.[5] Today, Norway maples tend to be most common in the Pacific Northwest, in southern Ontario, and along the Kennebec river in southern Maine. The roots of Norway maples grow very close to the ground surface, starving other plants of moisture. For example, lawn grass (and even weeds) will usually not grow well beneath a Norway maple, but English ivy, with its minimal rooting needs, may thrive. In addition, the dense canopy of Norway maples can inhibit understory growth.[25] Some have suggested Norway maples may also release chemicals to discourage undergrowth,[26] although this claim is controversial.[25] A. platanoides has been shown to inhibit the growth of native saplings as a canopy tree or as a sapling.[25] The Norway maple also suffers less herbivory than the sugar maple, allowing it to gain a competitive advantage against the latter species.[27] As a result of these characteristics, it is considered invasive in some states,[28] and has been banned for sale in New Hampshire[29] and Massachusetts.[30] The state of New York has classified it as an invasive plant species.[31] Despite these steps, the species is still available and widely used for urban plantings in many areas.

  • Fruit (samara): note the flat seed capsule and the angle of the "wings"
    Fruit (samara): note the flat seed capsule and the angle of the "wings"
  • Typical yellow fall foliage
    Typical yellow fall foliage
  • Atypical orange-red fall colour
    Atypical orange-red fall colour
  • Purple leaves of cultivar 'Schwedleri'
    Purple leaves of cultivar 'Schwedleri'
  • Twig and buds
    Twig and buds

Natural enemies

[edit]

The larvae of a number of species of Lepidoptera feed on Norway maple foliage. Ectoedemia sericopeza, the Norway maple seedminer, is a moth of the family Nepticulidae. The larvae emerge from eggs laid on the samara and tunnel to the seeds. Norway maple is generally free of serious diseases, though can be attacked by the powdery mildew Uncinula bicornis, and verticillium wilt disease caused by Verticillium spp.[32] "Tar spots" caused by Rhytisma acerinum infection are common but largely harmless.[33] Aceria pseudoplatani is an acarine mite that causes a 'felt gall', found on the underside of leaves of both sycamore maple (Acer pseudoplatanus) and Norway maples.[34]

References

[edit]
[edit]
Revisions and contributorsEdit on WikipediaRead on Wikipedia

Acer platanoides

View on Grokipedia
from Grokipedia
L., commonly known as the Norway maple, is a large in the family native to and western . It typically attains heights of 12 to 30 metres (40 to 100 feet), featuring a dense, rounded crown formed by spreading branches. The opposite, palmately compound leaves are five-lobed with sharply pointed tips, measuring 10 to 15 centimetres across, dark green above, and produce milky sap from the petiole when damaged; they turn yellow in autumn. In spring, before leaf expansion, it bears inconspicuous yellow-green flowers in erect clusters, followed by paired winged samaras that mature in autumn and aid wind dispersal. Introduced to in the mid-18th century as a hardy urban shade and street , A. platanoides has naturalized widely and is regarded as invasive in northeastern and midwestern regions, where its prolific seed production, shade tolerance, and competition suppress native flora such as sugar maple ().

Taxonomy and characteristics

Classification and phylogeny

Acer platanoides L. is a species within the genus Acer, family Sapindaceae, order Sapindales, class Magnoliopsida, phylum Magnoliophyta, kingdom Plantae. The family Sapindaceae encompasses approximately 150 genera and over 1,900 species, including maples, which were previously segregated in the now-synonymized Aceraceae under older classifications but integrated into Sapindaceae following molecular evidence confirming close relations with genera like Dipteronia. The binomial authority traces to Carl Linnaeus's Species Plantarum (1753), where it was distinguished by its platanoid leaf morphology resembling plane trees (Platanus). Within , A. platanoides resides in section Platanoidea, a group defined by five-lobed leaves with entire margins, paired samaras diverging at acute angles, and inflorescences in corymbs. This sectional placement aligns with traditional morphology-based , supported by early chloroplast DNA analyses demonstrating for Platanoidea alongside sections like Palmata and Macrantha. Phylogenetic studies using nuclear and markers reveal A. platanoides clustering with Eurasian species such as A. cappadocicum and A. heldreichii in core Platanoidea, though broader analyses indicate potential or conflict in sectional boundaries due to incomplete lineage sorting or hybridization. A 2019 phylogenomic reconstruction employing anchored hybrid enrichment of over 500 nuclear loci provided the first high-resolution Acer tree, positioning Platanoidea as derived within the genus's diversification, which originated in during the Eocene and involved multiple Northern Hemisphere dispersals. Divergence estimates place the Platanoidea lineage arising around 20-30 million years ago in the , coinciding with cooling climates favoring temperate forests. These findings underscore Acer's adaptive radiation via vicariance and long-distance dispersal, with A. platanoides's European distribution reflecting post-glacial recolonization from refugia.

Morphological description

Acer platanoides is a typically reaching heights of 12 to 30 (40 to 98 feet), with a trunk up to 1.5 and a broad, rounded crown featuring widely spreading, ascending branches. The bark on mature trees is gray, furrowed with even grooves, and develops a ridged or plated texture. Twigs are brown in winter, and buds are paired and blunt-ended. Leaves are opposite, simple, and palmately lobed with five sharply pointed lobes, measuring 100–150 mm in length and 100–180 mm in width, often broader than long, with coarsely toothed margins on the lobes. Petioles exude a milky white sap when broken, distinguishing it from native maples like sugar maple. blades are orbicular to triangular in outline and turn yellow in autumn. Flowers are small, yellow-green, radially symmetrical with five thin petals, arranged in erect corymbs or panicles approximately 5 cm across, blooming in to before or with leaf emergence. Fruits are paired schizocarpic samaras, each wing 3.5–5.5 cm long, with wings diverging at an acute angle of 170–180 degrees for horizontal dispersal. The exhibits a dense, symmetrical form with a shallow .

Identification features

Acer platanoides, commonly known as Norway maple, is a large typically reaching heights of 12 to 30 meters with a broad, rounded crown formed by ascending branches. Its leaves are opposite, simple, and palmately lobed with 5 to 7 acute-tipped lobes, measuring 10 to 18 cm across; the lobes are separated by narrow, V-shaped sinuses that do not extend to the leaf center, and the upper surface is dark green and glabrous while the lower surface features tufts of axillary hairs at vein junctions. A diagnostic trait is the milky white sap exuded from the petiole when broken, distinguishing it from native North American like sugar maple (). The bark on mature trunks is dark gray to brown, irregularly furrowed with flat-topped ridges and shallow fissures. Twigs are stout, reddish-brown, and pubescent when young, bearing opposite leaf scars; terminal buds are large (up to 8 ), ovoid, and reddish, often with a few pairs of scales. Flowers emerge in early spring before leaves, in erect, rounded corymbs of 15 to 30 yellow-green blooms, each with five sepals and petals about 3 to 4 long, providing a subtle display. Fruits are paired samaras, 3.5 to 5 cm long, with wings diverging at an acute angle (nearly horizontal) from the central axis; the seed cavity is compressed and flat, unlike the V-shaped cavity in sugar maple samaras, and they mature green before turning yellowish-brown in late summer, persisting into winter. These samara characteristics, combined with the leaf sap and axillary hairs, serve as key identifiers separating Norway maple from similar Acer species.

Native distribution and ecology

Geographic range in native habitat

Acer platanoides, commonly known as Norway maple, is native to , with its range extending from southern southward to and , and eastward across the continent to the . The species also occurs in western , including the region and northern . This distribution spans from roughly 40°N to 65°N , reflecting its adaptability to temperate climates across diverse terrains. The is absent from , including the , , the , and western , where it has been introduced rather than occurring naturally. In its native habitats, Acer platanoides thrives in forested areas, woodland edges, and river valleys, often up to elevations of 1,000–1,650 meters in mountainous regions such as the and central . Its wide native distribution underscores its status as the most widespread in , contributing to its historical use in and ornamental planting beyond its natural limits.

Habitat preferences and adaptations

Acer platanoides primarily inhabits lowland river valleys, riparian zones, and low montane areas within its native range across and western , where it occurs as a component of mixed forests. It favors deep, fertile soils that are moist yet well-drained, with neutral to slightly alkaline levels, and shows intolerance to strongly acidic conditions around pH 4 or nutrient-poor substrates deficient in . While optimal growth occurs in mesic environments with 1150 to 2600 growing degree-days above 5°C, the species can persist on drier, rocky slopes or temporarily flooded sites, though prolonged drought limits its performance. Seedlings exhibit , enabling establishment beneath canopies, though mature trees perform best in full sun to partial shade. Physiologically, A. platanoides demonstrates resilience to short-term flooding (up to four months) and develops in later juvenile stages, facilitated by efficient water use and root systems adapted to varied moisture regimes. Late-season leaf retention extends photosynthetic periods, providing a competitive edge in temperate climates with cold winters down to -24°C for insulated seedlings. Seed dispersal via wind-carried samaras, capable of traveling up to 50 meters in moderate breezes, further aids colonization within heterogeneous landscapes.

Role in native ecosystems

In its native European range, Acer platanoides functions primarily as a secondary canopy species in temperate mixed forests, forming small groups or scattered individuals rather than pure stands, and co-occurring with dominant trees such as (pedunculate oak) and (small-leaved lime). Its wide-spreading crown contributes to vertical forest stratification by casting dense shade that inhibits the growth of slower-developing plants and competitors. This shading effect helps maintain humidity in the , supporting associated adapted to partial shade in fresh, moist sites on deep, fertile soils with sub-acid to pH. The provides and resources for native , with its leaves serving as a primary source for various species, thereby supporting Lepidopteran populations integral to food webs. Seeds from its wind-dispersed samaras are consumed by birds and small mammals, facilitating cycling and dispersal within ecosystems. Flowers, which emerge in early spring before full leaf-out, attract insect pollinators, enhancing in pollinator-dependent communities. As one of Europe's most widespread native maples, A. platanoides exhibits that allows establishment beneath existing canopies, enabling it to regenerate prolifically via large cohorts in humid, nutrient-rich understories and contribute to long-term succession dynamics. In certain continental types, it achieves co-dominance, stabilizing mixed stands against disturbances like due to its robust and adaptability to elevations up to 1,400 meters in the .

Reproduction and life cycle

Flowering and seed production

Acer platanoides produces yellowish-green flowers in stalked corymbs, typically appearing in mid to late April as leaves begin to expand. In eastern North America, flowering occurs from late April to early June, triggered by warm temperatures around 15-20°C. The species is primarily insect-pollinated, with flowers attracting pollinators before full leaf-out to facilitate access. Fruits develop into paired samaras with widely diverging wings at approximately 180°, maturing in late summer. production is prolific, enabling the generation of large numbers of shade-tolerant seedlings annually. Seeds are wind-dispersed in fall via the winged samaras, which can travel laterally up to 50 meters from the parent in moderate breezes from three-quarters of the tree's height. Seeds exhibit physiological dormancy and require 90-120 days of cold stratification at 3-4°C for , often achieved naturally under winter snow cover. Viability remains high post-dispersal, supporting spring even in shaded understories, though disturbance can enhance establishment. Seed yield varies among cultivars, but the species generally demonstrates robust reproductive output conducive to rapid population expansion.

Growth dynamics and longevity

Acer platanoides demonstrates moderate to rapid juvenile growth, often reaching s of 10-15 meters within the first two decades under favorable conditions, with annual increments of 0.5-1 meter in early stages before tapering. In comparative studies, its radial growth can exceed that of native associates like sugar maple, with annual diameter increments averaging 4-5 mm in managed stands, influenced by , light availability, and competition. Growth dynamics shift with age, transitioning from upright-oval form to a broader, rounded canopy that promotes self-shading and reduced lower branch persistence, potentially limiting development but enhancing in mature specimens. Mature trees typically attain heights of 12-18 meters and similar crown spreads, though exceptional individuals in native habitats exceed 30 meters. Longevity varies by environment; in native European ranges, Acer platanoides can persist for 150-250 years under optimal forest conditions with minimal disturbance. In introduced regions such as , lifespan is frequently curtailed to 60-150 years due to factors including susceptibility, urban soil compaction, and allelopathic effects that alter site conditions over time. This reduced longevity reflects to novel pathogens and abiotic stresses, as evidenced by widespread decline in aging urban plantings.

Environmental tolerances

Acer platanoides exhibits broad environmental tolerances that contribute to its adaptability in both native European forests and introduced urban settings. It is hardy in USDA zones 4 to 7a, enduring minimum winter temperatures down to approximately -34°C (-30°F) while tolerating summer heat in temperate climates, though leaf scorch may occur on exposed, hot, dry sites. The species prefers full sun but demonstrates high , particularly during juvenile stages, allowing establishment under dense canopies. In terms of soil, A. platanoides thrives on moist, well-drained, fertile loams but adapts to a wide range from acidic (4.0) to slightly alkaline (up to 8.2), including compacted urban soils and those low in , though growth is suboptimal on highly sandy, clay-heavy, or lime-rich substrates. It shows moderate once established, resisting short-term dry spells but suffering under prolonged stress, and conflicting reports note occasional tolerance to periodic flooding for up to four months despite general aversion to waterlogged conditions. The tree displays notable resistance to urban stressors, including air pollutants such as ozone and , which supports its frequent use in street plantings. Salt tolerance varies: moderate for aerosol and soil de-icing salts in some assessments, yet field studies in high-salinity urban environments like indicate sensitivity leading to decline in over 50% of trees from 1973 to 2007. This discrepancy underscores context-dependent responses, with overall hardiness favoring establishment in polluted, disturbed habitats over pristine ones.

Cultivation and human uses

Historical introduction and planting

Acer platanoides, commonly known as Norway maple, originated in the temperate forests of extending into western , where it has been utilized in traditional and for its rapid growth and shade provision, though precise records of early native-range planting are limited. Cultivation records beyond its natural distribution begin in Britain, with the earliest documented instance in 1683, when George listed the species among trees transplanted from gardens. This introduction to the marked its adoption as an ornamental tree valued for its broad canopy and adaptability to varied soils. The species reached North America in the mid-18th century, introduced around 1756 by Philadelphia botanist John Bartram, who obtained seedlings from England via Philip Miller of London and propagated them in his nursery. Bartram began commercial distribution by 1762, promoting it as a hardy shade tree suitable for farms, estates, and early urban plantings in the northeastern United States. Initial plantings emphasized its tolerance to transplanting, pollution, and compacted soils, attributes that distinguished it from slower-growing native maples like Acer saccharum. By the 19th and early 20th centuries, A. platanoides gained widespread favor in European and North American for avenue and park plantings, with selections for columnar forms aiding its use in constrained urban spaces. Its propagation through nurseries accelerated dissemination, leading to extensive establishment in temperate zones where it was planted for aesthetic and functional shade benefits prior to recognition of its invasive potential.

Ornamental and urban applications

is employed in ornamental landscaping for its fast growth, reaching 12-18 meters in height with a dense, rounded canopy that delivers effective shade coverage. Its broad, five-lobed leaves provide a lush appearance, transitioning to yellow hues in autumn, enhancing visual appeal in parks and gardens. The species exhibits showy yellow-green flowers in spring, contributing to its decorative value. In urban settings, A. platanoides serves as a and tree due to its adaptability to compacted soils, , , , and de-icing salts. It tolerates a pH range from acidic to alkaline and thrives in clay, , or , making it resilient in modified environments like islands and roadside plantings. The tree's ease of and resistance to wind and damage further support its use in municipal forestry programs. Selected cultivars amplify ornamental traits; for instance, 'Crimson King' features maroon-purple foliage throughout the season, while 'Schwedleri' displays red-purple young leaves maturing to green. These varieties maintain the species' urban tolerances, including to and soil extremes, allowing for colorful accents in landscapes without sacrificing hardiness. Historically, it ranked as the most planted for eastern U.S. urban streets, valued for uniform structure and low maintenance.

Timber, medicinal, and other utilitarian uses

The wood of Acer platanoides is employed sparingly as lumber, primarily in , for veneer production and specialty items such as tool handles, gunstocks, and violins due to its fine structure and acoustic qualities. It exhibits moderate hardness (Janka hardness of 1,010 lbf) and straight grain, rendering it workable for turning and gluing, though it tends to burn during high-speed machining and offers low resistance to decay. Medicinal applications specific to A. platanoides are minimally documented, with the sap suitable for beverage or syrup production but lacking established therapeutic validation; broader uses within the Acer genus include traditional remedies for rheumatism, bruises, eye ailments, and pain relief, supported by phytochemical reviews but requiring species-specific verification. Other utilitarian roles encompass for , construction of boxes, crates, and pallets, as well as and small turned objects, leveraging its availability in managed forests despite inferior compared to hard maples.

Selected cultivars

Numerous cultivars of Acer platanoides have been selected for ornamental qualities, including variations in foliage color, crown shape, and growth vigor, with over 100 developed for commercial use in . These selections often emphasize tolerance to urban conditions while enhancing aesthetic appeal in landscapes. 'Crimson King' features rich purple-red foliage throughout the growing season, originating from a 1937 selection in and introduced in the United States by 1947; it grows to large sizes suitable for parks and s but produces dense shade that can suppress understory growth. 'Emerald Queen', selected in in 1963, exhibits vigorous upright growth with a balanced crown, making it popular as a street due to its lustrous leaves and adaptability to pollution. 'Globosum' forms a compact, globular crown on a standard, with bronzy-green emerging leaves turning dark green; listed since 1873 from , it is favored for small spaces and formal plantings despite slower growth. 'Drummondii' displays green leaves with creamy-white variegated margins, reaching up to 12 meters, introduced before 1903 from , though it requires protection from hot sun to maintain coloration. 'Schwedleri', an older , produces purplish-red young leaves that mature to green, offering seasonal color contrast and suitability for ornamental gardens. 'Deborah' emerges with bright red leaves transitioning to deep over 4-6 weeks, forming an oval-rounded habit ideal for accent planting. Some cultivars, such as 'Medzam' (), are noted for reduced seed production, potentially mitigating invasiveness concerns in introduced ranges.

Introduced ranges and invasiveness

Global distribution outside native range

Acer platanoides has been introduced extensively outside its native Eurasian range, with the most significant establishment occurring in . First imported to the around 1756, initially to eastern , the species was planted widely as an ornamental in urban and suburban landscapes across the continent. By the , it had escaped cultivation and naturalized in forested habitats, particularly in the northeastern and midwestern states from to and southward to , as well as in and in . In , the was introduced to the in 1683, where it has been cultivated ornamentally but shows limited naturalization compared to North American populations. Introductions to other continents, such as and , have occurred through ornamental plantings, though self-sustaining populations remain sparse and not widely documented as invasive. Overall, North American distributions dominate non-native occurrences, driven by historical planting preferences for its and rapid growth.

Introduction to North America

Acer platanoides, the Norway maple, was first introduced to in the mid-18th century as an ornamental tree. The earliest documented importation occurred in 1756, when botanist brought seedlings from to his nursery in , Pennsylvania. Bartram, recognized as America's first native-born professional botanist, included the species in his 1762 catalog, promoting it for its shade and aesthetic qualities after its prior cultivation in since 1683. Initial planting focused on urban and landscape settings in the , valued for its rapid growth, tolerance to pollution, and dense canopy. By the late 1700s, it had spread to other eastern states through nurseries and horticultural interest, though adoption remained limited until the 20th century. In , widespread planting accelerated after , particularly as a replacement for American elm (Ulmus americana) decimated by . Municipalities in and favored it for street tree programs due to its hardiness and low maintenance, leading to extensive establishment in urban forests by the and . Similar trends occurred in the United States during the and , amplifying its presence across the Northeast, Midwest, and .

Mechanisms of invasion and ecological impacts

Acer platanoides establishes invasive populations primarily through its exceptional shade tolerance, enabling seedlings to germinate and survive in low-light forest understories where native competitors struggle. Wind-dispersed samaras facilitate broad seed dispersal, while reduced predation pressure in introduced ranges—due to fewer specialized herbivores—enhances propagule viability compared to native ecosystems. Rapid juvenile growth and phenotypic plasticity allow it to exploit variable light conditions, with seedlings exhibiting twice the biomass under native red maple (Acer rubrum) canopies than vice versa. Competitive superiority manifests in dense canopies that transmit only 5% of to the , suppressing native regeneration. In experimental plots, native saplings grew 28% shorter beneath A. platanoides canopies than under native ones, with height reductions of up to 26% for species like A. rubrum in invaded areas. Survival rates for native seedlings, such as A. rubrum, drop to 60% under A. platanoides versus 75% under conspecifics, compounded by asymmetric resource competition. Ecological impacts include diminished diversity, as dense shading eliminates native wildflowers and spring ephemerals, while inhibiting shrub and tree recruitment. alterations arise from modified cycling, with elevated rates (p < 0.001) under A. platanoides leading to accelerated leaching and reduced availability for natives. Overall, invasions reduce and favor conspecific banks, potentially eroding native forest composition over decades.

Management and control strategies

Mechanical control methods are effective for small populations and seedlings of Acer platanoides. Seedlings and small saplings can be hand-pulled from moist soil, particularly early in the when are smaller and easier to extract completely, including roots. Larger saplings may require digging or mechanical pulling with , while mature trees can be cut to ground level, though resprouting is common without follow-up treatment. Repeated cutting or mowing can suppress regrowth over time but demands ongoing monitoring. Chemical control is typically necessary for larger trees or to prevent resprouting after mechanical removal. The cut-stump method involves felling the tree and immediately applying herbicides such as or to the fresh cut surface, targeting the layer for systemic uptake. Basal bark applications, using a 20% solution of ester in an oil-based carrier, are recommended for stems up to several inches in diameter, applied around the base during dormant seasons for optimal efficacy. Oil-based formulations of can also be foliar-sprayed on seedlings, but care must be taken to avoid non-target native vegetation. Integrated strategies emphasize prevention and long-term management due to the species' prolific production and dispersal. New plantings should be avoided, and existing seedlings removed promptly to limit spread; control efforts often extend beyond the immediate area to address seed rain from nearby mature . Post-removal site restoration with is advised to restore ecological function and prevent reinvasion, as A. platanoides alters soil conditions and suppresses understory recovery. In regions like the northeastern U.S., where it is not always legally mandated, voluntary removal is promoted through municipal programs and landowner education. Challenges include the tree's tolerance to urban stressors and potential for widespread resprouting, necessitating multi-year treatments for eradication.

Pests, diseases, and biological interactions

Natural enemies in native vs. introduced ranges

In its native range spanning central and eastern Europe to western Asia, Acer platanoides experiences substantially higher levels of foliar herbivory and fungal infection from co-evolved natural enemies than in introduced ranges such as North America. Quantitative assessments of leaf damage on fallen foliage reveal average herbivory rates of 7.4% in European sites (e.g., Norway, Slovakia, Germany) compared to 1.6% in North American sites (e.g., New York, New Jersey, Canada), representing over three times greater damage in the native range across multiple study years. Fungal leaf infections follow a similar pattern, averaging 3.7% in Europe versus 1.0% in North America. These disparities align with the enemy release hypothesis, whereby introduced plants evade specialist herbivores and pathogens, facilitating population expansion and invasiveness. Specific insect herbivores in the native range include such as Periphyllus lyropictus and Periphyllus testudinaceus, which form dense colonies on undersides, as well as gall-inducing midges like Drisina glutinosa that produce distinctive on leaves and shoots, and various leaf-mining insects targeting maple foliage. Vertebrate enemies, including birds and small mammals, also consume seeds more readily in , exerting additional population control absent or reduced in introduced areas. In , while some generalist insects and introduced pests like the Norway maple inflict damage, total herbivory remains low (e.g., 0.4–1.3% area loss), with no equivalent suite of specialists; damage, for instance, is negligible compared to native congeners like sugar maple. Pathogens exhibit parallel release dynamics, with European tar spot fungus () causing more widespread leaf lesions natively, though sporadic outbreaks occur in post-introduction. Overall, this reduced enemy pressure in introduced ranges—despite occasional establishment of translocated pests—contributes to A. platanoides' competitive advantage over native trees, as evidenced by lower damage relative to co-occurring species like . No targeted classical biological control programs have been implemented against A. platanoides in invasive contexts, relying instead on mechanical and chemical management.

Common pests and pathogens

Norway maple (Acer platanoides) is susceptible to several fungal pathogens causing leaf spots and blights, including anthracnose (Discula spp.), which produces irregular brown lesions on leaves and twigs, often leading to premature defoliation in wet springs. Tar spot, caused by , is particularly prevalent on this species, manifesting as black, tar-like fruiting bodies on leaves that reduce but rarely kill the tree. , induced by soilborne spp. fungi, is a significant affecting maple, blocking water flow and causing branches with yellowing leaves; it is more severe in stressed trees and can lead to dieback. Other notable pathogens include powdery mildew (Uncinula spp.), which forms white fungal growth on leaves, and Nectria canker (Neonectria spp.), producing sunken, discolored bark lesions that girdle branches. Bacterial leaf scorch (Xylella fastidiosa) causes marginal leaf browning and scorching, progressing inward over years. Sooty bark disease (Cryptostroma corticale) affects the tree as a host, producing spore masses under bark that can spread to native maples, though it causes limited damage to Norway maple itself. Root and crown rots from Phytophthora spp. occur under poor drainage, leading to basal cankers and tree decline. Insect pests are generally not severe, with no major defoliators consistently damaging mature trees. Scales, such as cottony maple scale (Pulvinaria innumerabilis), occasionally infest branches, forming waxy egg masses that excrete honeydew, promoting . The eriophyid Aceria pseudoplatani can deform young leaves and buds if infestations are heavy, though impacts are typically minor. Aphids and leafhoppers may cause minor feeding damage, but Norway maple shows relative resistance compared to native North American maples.

Comparisons with native congeners

Norway maple (Acer platanoides) demonstrates superior competitive ability against native North American congeners, particularly sugar maple (A. saccharum) and red maple (A. rubrum), through faster growth rates and enhanced resource acquisition. Seedlings of A. platanoides exhibit greater growth, enabling canopy gap capture up to a earlier than most native trees, including A. saccharum. In experimental comparisons, A. platanoides displays higher photosynthetic capacity and larger stem diameters than A. saccharum under varying light regimes, contributing to its dominance in mixed stands. Additionally, A. platanoides seedlings allocate more biomass to roots and produce more leaves than A. saccharum, enhancing establishment in conditions. Shade tolerance further favors A. platanoides over natives; its seeds germinate effectively in deep shade, surpassing A. saccharum in this trait, while adult cast denser shade that suppresses regeneration of species like A. rubrum. Norway maple's broader site adaptability, including disturbed habitats, contrasts with A. saccharum's restriction to rich, mesic soils, allowing invasion into diverse native maple-dominated forests. In resource use, A. platanoides captures more efficiently—over 150% relative to A. saccharum seedlings—and exploits available nutrients more effectively when co-occurring with the native, leading to reduced native recruitment. Ecological impacts include lower herbivory on A. platanoides in compared to , reducing pressure relative to natives like A. rubrum, whose seedlings face higher predation. Its shallow exacerbates competition by limiting water and nutrient access for native plants and seedlings. While A. rubrum tolerates wetter soils better than A. platanoides, the invader's earlier leaf-out and prolific seeding overwhelm such niches in upland s. Overall, these traits enable A. platanoides to displace congeners, altering composition where introduced.

References

  1. https://www.fs.usda.gov/database/feis/plants/tree/acepla/all.html
  2. https://plants.ces.ncsu.edu/plants/acer-platanoides/
  3. https://www.invasive.org/browse/subinfo.cfm?sub=3002
  4. https://landscapeplants.oregonstate.edu/plants/acer-platanoides
  5. https://plants.usda.gov/plant-profile/ACPL
  6. https://fsus.ncbg.unc.edu/show-taxon-detail.php?taxonid=3827
  7. https://www.researchgate.net/publication/236024878_Phylogenetics_of_Acer_Aceroideae_Sapindaceae_based_on_nucleotide_sequences_of_two_chloroplast_non-coding_regions
  8. https://ecommons.cornell.edu/bitstreams/e45af7be-b42c-4660-a626-dc18b5ed8f12/download
  9. https://naturalhistory.si.edu/sites/default/files/media/file/2016-frawley-poster.pdf
  10. https://onlinelibrary.wiley.com/doi/10.1111/jse.12535
  11. https://www.nature.com/articles/s41598-020-78145-0
  12. https://gobotany.nativeplanttrust.org/species/acer/platanoides/
  13. https://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?taxonid=275380
  14. https://extension.umd.edu/resource/norway-maple
  15. https://dendro.cnre.vt.edu/dendrology/syllabus/factsheet.cfm?ID=6
  16. https://www.nrs.fs.usda.gov/pubs/jrnl/1990/ne_1990_nowak_003.pdf
  17. https://www.euforgen.org/species/acer-platanoides
  18. https://auf.isa-arbor.com/content/16/11/291
  19. https://www.cabidigitallibrary.org/doi/full/10.1079/cabicompendium.2883
  20. https://forest.jrc.ec.europa.eu/media/atlas/Acer_platanoides.pdf
  21. https://www.woodlandtrust.org.uk/trees-woods-and-wildlife/british-trees/a-z-of-british-trees/norway-maple/
  22. http://www.columbia.edu/itc/cerc/danoff-burg/invasion_bio/inv_spp_summ/Acer_platanoides.html
  23. https://vtinvasives.org/sites/default/files/2016-10/NorwayMaple_finalTREATMENT.pdf
  24. https://journals.ashs.org/view/journals/horttech/19/1/article-p91.xml
  25. https://plants.usda.gov/plant-profile/ACPL/characteristics
  26. https://plantfacts.osu.edu/tmi/Plantlist/ac_oides.html
  27. https://bplant.org/plant/68
  28. https://www.agriculture.nh.gov/publications-forms/documents/norway-maple.pdf
  29. https://auf.isa-arbor.com/content/7/2/38
  30. https://www.glenridgenj.org/shadetree/norwaymaple/
  31. https://hort.ifas.ufl.edu/database/documents/pdf/tree_fact_sheets/aceplaa.pdf
  32. https://hort.ifas.ufl.edu/trees/ACEPLAD.pdf
  33. https://sunyorange.edu/inttreetour/acer_platanoides.html
  34. https://hort.ifas.ufl.edu/database/documents/pdf/tree_fact_sheets/aceplak.pdf
  35. https://www.mndnr.gov/invasives/terrestrialplants/woody/norwaymaple.html
  36. https://pmc.ncbi.nlm.nih.gov/articles/PMC7847709/
  37. https://www.columbia.edu/itc/cerc/danoff-burg/invasion_bio/inv_spp_summ/Acer_platanoides.html
  38. https://www.treesandshrubsonline.org/articles/acer/acer-platanoides/
  39. https://concordma.gov/789/Norway-Maple-Acer-Platanoides
  40. http://libraryexhibits.uvm.edu/omeka/exhibits/show/uvmtrees/norway-maple-introduction/norway-maple-history
  41. https://www.invasive.org/alien/pubs/midatlantic/acpl.htm
  42. https://elsoms.com/rest-of-world/trees/broadleaf-species/norway-maple-acer-platanoides
  43. https://mortonarb.org/plant-and-protect/trees-and-plants/norway-maple/
  44. https://www.natickma.gov/1838/Norway-Maple
  45. https://trees.umn.edu/norway-maple-acer-platanoides
  46. https://cipwg.uconn.edu/wp-content/uploads/sites/244/2013/10/final-Norway-Maple-factsheet.pdf
  47. https://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=b975
  48. https://forestupdate.frec.vt.edu/content/dam/forestupdate_frec_vt_edu/newsletter/archives/2017/31_4/GagnonNorwaymaple.pdf
  49. https://auf.isa-arbor.com/content/8/9/241
  50. https://www.wood-database.com/norway-maple/
  51. http://www.naturalmedicinalherbs.net/herbs/a/acer-platanoides=norway-maple.php
  52. https://pubmed.ncbi.nlm.nih.gov/27132717/
  53. https://blog.irontreeservice.com/tree-profiles-norway-maple-cultivars-part-5/
  54. https://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?taxonid=254944
  55. https://onnurserycrops.wordpress.com/2016/07/07/research-shows-some-norway-maple-cultivars-are-not-invasive/
  56. https://www.iucngisd.org/gisd/species.php?sc=979
  57. https://nwwildflowers.com/compare/?t=Acer%2Bplatanoides%2C%2BAcer%2Bpseudoplatanus
  58. https://www.ontarioinvasiveplants.ca/wp-content/uploads/2021/05/BMP_NorwayMaple_April2021_WEB.pdf
  59. https://treecanada.ca/resources/tree-killers/norway-maple/
  60. https://www.brandywine.org/conservancy/blog/invasive-species-spotlight-norway-maple
  61. https://ecologicalprocesses.springeropen.com/articles/10.1186/s13717-020-0213-5
  62. https://besjournals.onlinelibrary.wiley.com/doi/full/10.1111/j.1365-2745.2007.01337.x
  63. https://cipwg.uconn.edu/ci-norway-maple/
  64. https://www.dnr.state.mn.us/invasives/terrestrialplants/woody/norwaymaple.html
  65. https://woodyinvasives.org/woody-invasive-species/norway-maple/
  66. https://extension.umd.edu/resource/invasives-your-woodland-norway-maple
  67. https://www.maine.gov/dacf/mnap/features/invasive_plants/acerplat.htm
  68. https://kingcounty.gov/en/dept/dnrp/nature-recreation/environment-ecology-conservation/noxious-weeds/identification-control/norway-maple
  69. https://link.springer.com/article/10.1007/s10530-008-9255-9
  70. https://www.forestpests.org/vd/8195.html
  71. https://www.forestpests.eu/pest/drisina-glutinosa
  72. http://www.ukflymines.co.uk/Keys/ACER.php
  73. https://portal.ct.gov/caes/fact-sheets/plant-pathology/common-diseases-of-maple
  74. https://content.ces.ncsu.edu/common-disease-pests-of-maple-in-north-carolina
  75. https://www.umass.edu/agriculture-food-environment/landscape/fact-sheets/tar-spot-of-maple
  76. https://www.forestresearch.gov.uk/tools-and-resources/tree-species-database/131554-norway-maple-nom-2/
  77. https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/acer-platanoides
  78. https://hort.ifas.ufl.edu/database/documents/pdf/tree_fact_sheets/aceplae.pdf
  79. https://academic.oup.com/jipm/article/4/1/B1/820374
  80. https://portal.nifa.usda.gov/web/crisprojectpages/0195980-a-plague-of-maples-modeling-the-spread-of-an-invasive-exotic-tree-species-acer-platanoides.html
  81. https://academic.oup.com/treephys/article/32/11/1339/1646606
  82. https://besjournals.onlinelibrary.wiley.com/doi/full/10.1111/j.1365-2745.2007.01270.x
  83. https://bplant.org/compare/68-93
  84. https://www.mdpi.com/1999-4907/3/2/190
  85. https://www.fs.usda.gov/research/publications/iitf/iitf_gtr_54.pdf
  86. https://kingstonrotary.ca/stories/why-is-the-norway-maple-an-%25E2%2580%259Cenemy%25E2%2580%2599-of-our-native-biodiversity
  87. https://extension.usu.edu/yardandgarden/research/maples-in-the-landscape/
  88. https://research.fs.usda.gov/treesearch/18721
Add your contribution
Related Hubs
User Avatar
No comments yet.