Sycamore (Acer pseudoplatanus)

KingdomPlantae
PhylumAnthophyta
ClassMagnoliopsida
OrderSapindales
FamilyAceraceae
GenusAcer (1)
SizeHeight: 20 - 35 m (2)(1)
Leaf length: 10 - 25 cm (2)
Seed diameter: 0.5 - 1 cm (2)
Top facts

The sycamore has yet to be classified by the IUCN.

The sycamore (Acer pseudoplatanus) is a large, deciduous tree (2) (3) (4) with a straight, cylindrical trunk (5) and erect branches, which form a large, domed crown (2) (5). The dark green leaves are long and broad, with five pointed lobes and toothed edges (2) (3) (5). The colouration of the leaves may change to bright yellow in autumn (5) (6).

When a sycamore is young, it has smooth, grey bark (2) (5), which becomes rougher as it ages, eventually breaking up into scales, exposing the pale brown or pinkish inner bark (2). The pale green or yellow flowers of this species have very thin petals, a white stamen and bright yellow anthers (5).  Each seed has a long wing, which helps to increase the distance it travels from the parent plant (2). The seeds of the sycamore are arranged in pairs in a ā€˜Vā€™ shape (5).

The native distribution of the sycamore encompasses most of central and southern Europe, including Germany, Spain, France, Italy, Bosnia, Greece, Poland, Slovakia and Romania (5), as well as parts of southwest Asia (2). It has been introduced into other areas of Europe where it now has become established, including Ireland, the United Kingdom, Belgium, the Netherlands and Scandinavia (5). Introduced populations also exist in New Zealand and North and South America (3).

In its native range, the sycamore is found in woodlands among birch (Betula species) and fir trees (Abies species) (5). In its introduced range, this species is found in various types of woodland (3) (4) (5), estates, parks, gardens, road sides, along railways and in disturbed areas (3) (5). It can grow in a wide variety of soils and is usually found between elevations of 500 and 1900 metres (5).

The monoecious flowers (3) (5) of the sycamore appear in April, shortly after the leaves (6). The flowers are pollinated by insects (3), and around six months after pollination occurs, the seeds are mature (2). The seeds can travel a considerable distance from the parent tree, with the average seed landing between 30 and 80 metres away, although they may be carried many kilometres during strong winds (3). The sycamore can produce over 10,000 seeds per year (5).

A highly adaptable and tolerant species, the sycamore withstands high levels of pollution and salt spray (2) (3). It has a complex, heavily branched root system which helps it to remain stable during extreme wind (5).

A long-living species, the sycamore can survive for over 500 years (6).

The sycamore is an invasive species and causes many ecological problems due to its fast growth rate, adaptability and high levels of seed production. Areas which this species has invaded suffer from reduced biodiversity, damaged ecological processes and an altered ecosystem composition (5).

The dense shade created by the large canopy of the sycamore prevents light from reaching the ground (3) (7), which prevents any other plants from growing nearby (3). In Madeira, the invasion of the sycamore is responsible for the reduced population size of a rare, endemic orchid (5), and it has the ability to completely displace native tree species from woodlands. The sycamore is highly adaptable and colonises new areas with ease (3). The seeds of the sycamore can remain viable for long periods of time until environmental conditions favour their growth (5).

The sycamore is also damaging to fauna in introduced areas as they are not able to support as many herbivorous insects as native trees, which can reduce the overall biodiversity of the habitat (3).

The extremely slippery leaves of the sycamore cause many disruptions on railways and other transport networks (7).

Conservation groups spend large amounts of time and money removing sycamore seedlings from protected areas (3) (7). Removal is possible, although the roots must be completely eliminated to ensure that the individual will not grow back, and any leftover stumps must be treated with herbicide (5).

It is thought that the most effective method for managing this damaging invasive species is to use coppicing rather than attempting eradication (7).

More information on the sycamore as an invasive species:

More information on tree conservation:

This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact:
arkive@wildscreen.org.uk

  1. Integrated Taxonomic Information System (ITIS) (November, 2013)
    http://www.itis.gov/
  2. MobileReference (2008) Encyclopedia of Trees and Shrubs of the World. MobileReference, Boston.
  3. GB Non-native Species Secretariat (NNSS): Factsheet - Sycamore (November, 2013)
    https://secure.fera.defra.gov.uk/nonnativespecies/factsheet/factsheet.cfm?speciesId=25
  4. Preston, C.D., Pearman, D.A. and Dines, T.D. (Eds.) (2002) New Atlas of the British and Irish Flora. Oxford University Press, Oxford.
  5. Commonwealth Agricultural Bureaux International (November, 2013)
    http://www.cabi.org/isc/
  6. Godet, J. (1986) Collins Photographic Key to the Trees of Britain and Northern Europe: A Guide to Identification by Leaves and Needles. William Collins and Sons & Co Ltd, London.
  7. Mabey, R. (1996) Flora Britannica. Sinclair-Stevenson, London.