Plane trees of various species are native to North America, eastern Europe and Asia. They have been introduced to the United Kingdom, where they are widely planted in town and city streets, parks and public gardens for their amenity and shade, and resilience to air pollution and water shortages.
The species most commonly seen in the United Kingdom is London plane (Platanus x acerifolia, syn. P. hispanica). This is a naturally occurring hybrid of western or American plane (Platanus occidentalis), also known as American sycamore, and eastern or Oriental plane (P. orientalis).
A number of cultivars are identified, but there is no knowledge about their relative merits in British forestry.
London plane is a light-demanding species which reaches large sizes, tolerates pollution, and can be very long lived. It is cold hardy to -29°C, but is sensitive to exposure, particularly to cold, drying winds.
It grows best on soils of medium to rich nutrient status and fresh to wet soil moisture. However, it will grow on drier soils, and is drought tolerant. It is not suited to very wet or alkaline soils.
If used in forest plantations it needs early and regular thinning to provide adequate space for crown development.
Pests and pathogens
Plane trees are commonly affected by anthracnose, caused by the fungus Apiognomonia veneta, which mostly causes only shoot and leaf death, but the effects can sometimes be severe.
Two other fungal pathogens which are significant in Europe could become very damaging to Platanus species in the UK.
One is canker stain of plane, also known as plane tree wilt, caused by the fungus Ceratocystis platani. This disease now occurs in several European countries and has caused considerable damage to plane trees, including to the famous avenue of plane trees lining the Canal du Midi in France.
The other is Massaria disease, in which the fungus Splanchnonema platani is believed to play at least some part. It attacks the bark and cambium on the branches of London plane, causing sudden branch breakage, creating a public safety issue in towns and cities.
London plane is likely to benefit from climate warming, and it might prove a useful forest tree on warmer sites in eastern lowland Britain.
It produces attractive timber which is used in some countries for veneer and flooring, as well as plywood and pallets.
Its tolerance of air pollution and drought has led it its being widely planted for shade and amenity in UK towns and cities, especially in southern England.
London plane is categorised as a Plot-stage species. These are species that have not been planted on any significant scale but have demonstrated silvicultural characteristics in trial plots and have qualities suitable for forestry objectives to justify further testing and development.