Taxonomic name: Acer ginnala (Maximowicz)
Synonyms: Acer ginnala subsp. theiferum (Fang), Acer ginnala var. euginnala (Pax), Acer tataricum, Acer tataricum subsp. aidzuense, Acer tataricum subsp. semenovii, Acer tataricum subsp. tataricum, Acer tataricum subsp. tataricum var. torminaloides, Acer tataricum var. laciniatum (Regel), Acer theiferum (Fang)
Common names: Amur maple (English-United States), Amur-Ahorn (German-Germany), érable du fleuve Amour (French-Canada), érable ginnala (French-Canada), Feuer-Ahorn (German-Germany), ginnala maple (English-United States), Mangolian vaahtera, Siberian maple (English)
Organism type: tree
Acer ginnala, commonly known as Amur maple, is a decidous tree, native to Russia and northern China. It was introduced into the United States as an ornamental, due to its vibrant colours in autumn. It has since escaped from cultivation and has the potential of becoming naturalised. The Amur maple is tolerant of a wide range of environmental factors including temperature, drought, soil, pH and light.
Acer ginnala is a small ornamental tree that at maturity reaches a height of 4.5-6 metres (Mehrhoff et al. 2003). The trunk is multi-stemmed with smooth gray bark that becomes furrowed with age (VTFD, 2006). The leaves are opposite, simple, three lobed with doubly serrate margins (VTFD, 2006). The terminal lobe is noticeably much longer than either adjacent lobe, with a leaf length between 2.5-7.5cm (Mehrhoff et al, 2003). The twig is slender, reddish-brown, glabrous, with pale lenticels and short vegetative buds (VTFD, 2006).
agricultural areas, natural forests, ruderal/disturbed, urban areas
The Amur maple can grow in a wide range of habitats, from open to distrubed forests, early successional forests, streamsides, swamps, urban areas, roadsides, edges, and gardens (Mehrhoff et al. 2004). This species of maple can establish in a variety of soils, from sandy loam to heavy clays (Gilman, 1993) and acidic and alkaline pH ranges of 6.1-7.5 (FS, 2005). The Amur maple can withstand prolonged periods of dryness, but grows optimally in moist, well-drained soils (FS, 2005). It is salt tolerant (FS, 2005) and is temperature hardy to Zone 3 (-40°C to -34°C) through Zone 9 (-6°C to 0°C) with maximum and minimum winter temperatures limiting its southern and northern range respectively (Tree Link, undated). It prefers full sun, but can tolerate partial shade (Bernheim, undated).
Acer ginnala has the potential to displace native vegetation, including native maple species, due to its tolerance of partial shade and its ability to shade out other species (FS, 2005). The Amur maple also has the potential to outcompete native flora with its ability to establish in a wide range of habitats and environmental conditions (Mehrhoff et al. 2003). Maples can also release compounds that can inhibit the growth of nearby plants (Morris, 2004). In the United States this species is currently listed only as an invasive in Wisconsin and as a noxious weed in Conneticut (USDA, 2007), however the Forest Service lists the species as invasive in the states of Illinois, Massachusetts, Missouri, New York, Vermont, Conneticut, and Wisconsin (FS, 2005).
The Amur maple is used mainly for ornamental purposes, having bright red leaves in the fall, red seed pods in winter, fragrant flower clusters, and a spreading crown which makes it ideal for screenings and hedges (Gilman, 1993). This species also has some potential value as habitat for wildlife, providing food and shelter (Bernheim, undated). Traditionally in its native range, the leaves were dried and used as a preservative for food storage, or made into a dye (Morris, 2004). The young leaves could also be subtstituted for tea and contains an antioxidant, anti-inflammatory, and anti-tumor compound called quercetin (Morris, 2004).
Native range: Russian Federation, Mongolia, China, Japan, Korea (GRIN, 2007).
Known introduced range: United States (Wisconsin, Conneticut, Illinois, Massachusetts, Maine, New Hampshire, New York, Pennsylvannia, Vermont, Ohio, Michigan, North Dakota, Iowa, Kentucky, Washington, Minnesota) (USDA, 2007; Menashe, 2004).
Introduction pathways to new locations
For ornamental purposes: Introduced to New England in 1860 for use as an ornamental tree in the landscape due to its brilliant red autumn colors (Mehrhoff et al. 2003).
Local dispersal methods
For ornamental purposes (local): The Amur maple is readily propagated by seed and vegetative reproduction through cuttings and layering (Morris, 2004).
Garden escape/garden waste: Can escape into natural forest areas through seed production and establishes easily due to its tolerance of a wide variety of environmental factors, including soil, pH, light, temperature, and water (Mehrhoff et al. 2003)
Horticulture (local): The green industry is a major contributor to the propagation, distribution and establishment of ornamental invasive species in the United States (Li et al. 2004).
On animals (local): The winged samaras of Acer ginnala are dispersed by wind (Mehrhoff et al. 2003).
Preventative measures: For invasive species that are considered ornamental one management option is to restrict the planting of such plants in a cultivated landscape (Barton,et al. 2004). Other preventive measures can arise from legislation and policy establishing the restriction of sale and possession of potentially aggressive and invasive plant species (Li et al. 2004). A survey (Peters et al. 2006), showed that some regulation and codes of conduct in the horticulture industry was acceptable to businesses and professionals. Other preventitive actions are education on the retail and consumer level, as well as education in the forms of newsletters and conferences for professionals in the industry (Peters et al. 2006).
Physical: Some mechanical means of control are through pulling or cutting the tree back as close to the ground as possible (FS, 2005), since this species can tolerate heavy pruning (Bernheim, undated). Another physical control option is through prescribed burning (FS, 2005), however this will not eradicate it (Minnesota DNR, 2007).
Chemical: General herbicides can be used as an effective control option following labeled guidelines for application (FS, 2005). Glyphosate and triclopyr applied at the base of the stump after an initial cutting are recommended (Minnesota DNR, 2007).
Biological: New areas of genetic research and plant breeding technology are now available for some forms of control of ornamental plants that could be a threat as invasive species. Plant gene technology for producing male and female sterility cultivars, as well as seed sterility, and parthenocarpy through the use of hormones and gene mediated vectors are all new possibilities to allow the cultivated use of ornamentals without the risk of them reproducing in the wild (Li et al. 2004). However this type of genetic engineering is relatively new and not entirely without risk. Some of the species tested can cross and reproduce with similar species of the same genus that are wild type (Li et al. 2004). This type of management would also only function in preventing new introductions into the wild and would not be applicable for already established populations(Li et al. 2004). Another drawback to sterile breeds of ornamentals is that it is not an effecttive management strategy for plants that mainly spread by vegetative means (Li et al. 2004). Several native species of fungi, arthropods, and diseases exist that could be used as potential biological controls, but no known species are being tested as a control agent for release at this time.
Integrated management: Very little research and monitoring has been performed on the status and distribution of the Amur maple (Mehrhoff et al. 2003), making it difficult to determine its occurrence and the effect it has on native populations.
Acer ginnala requires moist, well-drained soils for optimal growth. The use of fertilisers and irrigation can cause this species to grow rapidly (Gilman, 1993).
The Amur maple develops hemaphroditic flowers (Morris, 2004). The flowers are white, to creamy pale yellow, fragrant infloresences (VTDF, 2006) on peduncled panicles (Mehrhoff et al. 2003).
Acer ginnala is a perennial tree that flowers from May-June. The fruits that develop are reddish-brown, nearly parallel samaras about 2cm long. The samaras can persist through the winter and are dispersed by the wind (Mehrhoff et al. 2003).
Principal sources: Mehrhoff, L.J., Silander, Jr., J.A., Leicht, S.A., Mosher, E.S., & Tabak, N.M., 2003, IPANE: Invasive Plant Atlas of New England, Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT.
Forest Service (FA)., May 9, 2005. Forest Health Staff, USDA, Weed of the Week, Amur Maple Acer ginnala, Newton Square, PA.
Compiled by: National Biological Information Infrastructure (NBII) & IUCN/SSC Invasive Species Specialist Group (ISSG)
Last Modified: Friday, 11 May 2007