Acer pseudoplatanus

Acer pseudoplatanus
Sycamore Maple leaves
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Rosids
Order:	Sapindales
Family:	Sapindaceae[1]
Genus:	Acer
Species:	A. pseudoplatanus
Binomial name
Acer pseudoplatanus L.

Acer pseudoplatanus, the sycamore maple, is a species of maple native to central Europe and southwestern Asia, from France east to Ukraine, and south in mountains to northern Spain, northern Turkey, and the Caucasus.^[2][3] It is not related to other trees called sycamore or plane tree in the Platanus genus. Its apparent similarity to the species of that genus led to its being named pseudoplatanus, using the prefix pseudo- (from the Ancient Greek for "false").

Other common names for the tree include false plane-tree,^[4] great maple,^[4] Scottish maple,^[4] mock-plane,^[5][6] sycamore,^[4][6] or celtic maple.^[7]

Description

The sycamore maple is a large deciduous tree that reaches 20–35 m tall at maturity, with a broad, domed crown. On young trees, the bark is smooth and grey but becomes rougher with age and breaks up in scales, exposing the pale-brown-to-pinkish inner bark. The leaves are opposite, large, 10–25 cm long and broad with a 5–15 cm petiole, with leathery texture, palmately veined with thick veins protruding on the underside surface, with five lobes with toothed edges, and dark green in colour with whitish underside; some cultivars have purple-tinged or yellowish leaves. The leaves are often marked with black spots or patches which are caused by the fungus Rhytisma acerinum.^[8] The monoecious yellow-green flowers are produced in spring on 10–20 cm pendulous racemes, with 20–50 flowers on each stalk. The 5–10 mm diameter seeds are paired in samaras, each seed with a 20–40 mm long wing to catch the wind and rotate when they fall; this helps them to spread further from the parent tree. The seeds are mature in autumn about 6 months after pollination.^[3][9]

The sycamore is able to produce suckers from roots when they are exposed to sunlight after the mature tree has fallen.

A number of species of Lepidoptera use the leaves as a food source; see Lepidoptera that feed on maples.

The name "sycamore" originally belongs to the fig species Ficus sycomorus native to southwest Asia (this is the sycamore or sycomore referred to in the Bible). The name was later applied to this species (and others; see also Platanus) by reason of the superficial similarity in leaf shape.

Cultivation and uses

Sycamore maple bark on a mature tree

It is noted for its tolerance of wind, urban pollution and salt spray, which makes it a popular tree for planting in cities, along roads treated with salt in winter, and in coastal localities. It is cultivated and widely naturalised north of its native range in northern Europe, notably in the British Isles and Scandinavia north to Tromsø, Norway (seeds can ripen as far north as Vesterålen); Reykjavík, Iceland; and Tórshavn on the Faroe Islands. It now occurs throughout the British Isles, having been introduced in the 17th century.^[10]

Ted Green (2005) believes that the sycamore has been present in Britain since at least the Bronze Age citing that Sycamore pollen has often been confused with that of Field Maple in Bronze Age and Iron Age burials. He suggests that it should be renamed "Celtic Maple".

The lack of old native names for it has been used to prove its absence in Britain before introduction in around 1487, but this is challenged by the presence of an old Scottish Gaelic name for the tree, fior chrann which suggests a longer presence in Scotland at least as far back as the Gaelic settlement at Dal Riada. This would make it either an archaeophyte (a naturalised tree introduced by humans before 1500) or perhaps native if it can be seen to have reached Scotland without human intervention.

At the moment it is usually classified as a neophyte, a plant that is naturalised but arrived with humans on or after the year 1500.^[11] It has been suggested that it could have been common up until Roman times when it went through a decline possibly brought about by climate change and human activities, surviving only in the mountains of Scotland.

In North America, escapes from cultivation are most common in New England, New York City and the Pacific Northwest. It is planted in many temperate parts of the Southern Hemisphere, most commonly in New Zealand and on the Falkland Islands.

The popular cultivar 'Brilliantissimum' is notable for the bright salmon-pink colour of the young foliage.

It is planted for timber production; the wood is white with a silky lustre, and hard-wearing, used for musical instrument making, furniture, wood flooring and parquetry. Occasional trees produce wood with a wavy grain, greatly increasing the value for decorative veneers. The wood is a medium weight for a hardwood, weighing 630 kg per cubic metre.^[12] It is a traditional wood for use in making the backs, necks and scrolls of violins. The wood is often marketed as rippled sycamore.^[13] Its uses are mainly indoor due to its perishability when in contact with soil.^[12]

The flowers produce abundant nectar, which makes a fragrant, delicately flavoured and pale-coloured honey.

It is also used as a species for medium to large bonsai, in many areas of Europe where some fine specimens can be found.^[14]

Invasive species

It is considered an environmental weed in some parts of Australia (Yarra Ranges, Victoria),^[15] and also Mount Macedon, near Daylesford, parts of the Dandenongs and Tasmania where it is naturalised in the eucalypt forests, ^[16] New Zealand,^[17] the United States,^[18] environmentally sensitive locations in UK ^[19] and Norway.^[20]

Oscillants

As in a number of other species, on wet ground the rocking movement of a tree in high winds may result in the oscillatory movements of water within pools formed from groundwater at the base of such trees. Water moves up and down with this back and forth movement of the tree, resulting in water rising up and withdrawing, often expelling liquified soil and creating cavities amongst the roots. These features are known as oscillants.^[21]

• 

  A full oscillant.

• 

  Half-full stage.

• 

  Oscillant empty.

The Darnley plane tree

The Darnley Sycamore

Mary, Queen of Scots, is said to have nursed her sick husband, Henry Stuart, Lord Darnley, back to health under this Plane (Plane is the Scottish name for the species) tree at Darnley in Glasgow. Queen Mary came to Glasgow early in 1567, having left Holyrood Place in Edinburgh on 24 January to collect her husband.

Darnley had reportedly contracted small-pox and the Queen intended to bring him back to Holyrood on a litter as he was too weak to ride a horse. Darnley returned with his wife, only to be murdered a few days later on 10 February.^[22]

References

External links

Wikimedia Commons has media related to: Acer pseudoplatanus

• University of Connecticut - Acer pseudoplatanus page
• Watch more sycamore (Acer pseudoplatanus) video clips from the BBC archive on Wildlife Finder