Splanchnonema platani

The disease, Massaria (Splanchnonema platani), was previously found only in Germany and Holland but has now been discovered in the UK. The disease affects London Plane trees (Platanus ‘x’ hispanica). Whilst Planes are not native trees as they were introduced to the UK some 300 years ago, they now form an integral part of London’s landscape. The tree was such a significant feature of the capital that it became known as the London Plane. These are some of the tallest of the capital’s trees and one of the most planted.

This picture on the right below shows an example of an infected branch. The top half of the branch shows the decayed deadwood due to the Massaria infection and the bottom half shows live wood.

London Planes are notoriously disease tolerant, have very few current threats from pests and disease and are very resilient to changes in environmental conditions. The discovery of the Massaria fungus in the UK poses a real threat to this tree species in England’s capital and other cities and towns. It also presents a huge problem for the specialists that manage them. This fungus can rapidly decay branches, making them liable to fall. It was originally thought to affect only unhealthy trees but has now been found on healthy trees as well.

As it was first identified in Europe during 2003, very little is known about how the disease spreads. Once the disease has been confirmed, the only solution is to remove any branches that show signs of the infection to prevent them from failing. This unfortunate branch removal could lead to the disfiguration of many beautiful trees. Currently, there has been no need to remove any entire trees. Due to the speed that the disease decays branches, some Local Authorities are changing their inspection programs for all London Plane trees in high risk areas. At a time when councils are having to find significant cuts, this disease demands that Tree Officers undertake more inspections and pruning work that will compound the financial problems for tree managers.