The Acer Up Our Sleeves

Condemned as a weed tree, the sycamore is blamed for leaves on the line and sticky windscreens, but are we overlooking a pollution-tolerant specimen that plants itself for free, asks Jack Watkins

Jack Watkins

If the Sycamore Gap tree, on the Northumbrian stretch of Hadrian’s Wall, seems to carry a self-satisfied air, it’s with good reason. The picture-perfect nature of the site gained it an international profile when it served as a backdrop in the Hollywood smash-hit feature film of 1991, Robin Hood: Prince of Thieves. More recently, it won the Woodland Trust’s English Tree of the Year award (2016), came fifth in a European equivalent competition and was back in front of the cameras in the ITV detective drama series Vera.

Sycamores, on the whole, don’t win prizes —at least not in this country. Last year, one planted on a tower of Colchester Castle, Essex, to mark Napoleon’s defeat at Waterloo in 1815, tried to emulate the Gap Tree by getting shortlisted in the latest Tree of the Year competition. It didn’t win and the suspicion is that, as with the Gap Tree, it was allowed in on account of the oddball location as much as for being a striking specimen in its own right.

In fact, mention the name sycamore in some conservationist circles and all you will get is dark looks. The problem is that it’s a rampant coloniser. The winged, winddispersed seeds can travel considerable distances and they’ll sprout up anywhere, in town or country gardens, along railway embankments, in parks, cemeteries, hedgerows, fields and woods. It is in the last of theset hat it’s a real bugbear. The saplings can live for years in the shade, but, once they get a toehold, can take over an entire wood. They deny other species light and, within a relatively short space of time, the balance of plants and trees within may be altered.

For this reason, the sycamore, an introduced, naturalised species in Britain, is sometimes pejoratively described as a weed tree or alien. Is there an element of national bias to this? The beloved ash, for instance, can be prolific to the point of being invasive. As is the sycamore, it is shade tolerant in its early stages and capable of regenerating at a rate of 150,000 seedlings per hectare (2½ acres). The ash, however, is almost up there with the oak as a symbol of our land and so doesn’t attract the same opprobrium, except among foresters.

The family tree

Sycamore (Acer pseudoplatanus) is a member of the vast maple family, of which about 12 among the Acer genus are native to Europe. In Britain, the sole native is the field maple (Acer campestre), a reassuringly homely, somewhat unobtrusive presence in hedgerows until autumn, when its leaves turn a striking yellow. Leaves are five-lobed, as are those of the sycamore, but much smaller. Norway maple (Acer platanoides) was introduced to Britain in the 17th century and naturalised. Shorter and more slender than sycamore, its leaves are thinner textured and more finely pointed.

Native or naturalised?