Massaria disease affects London planes, platanus hispanica, most notably reported since 2009. Although the disease itself doesn’t seem to affect the health of the tree it can cause branches to drop. As Planes are often planted in urban areas this is cause for concern. The fungus itself has been found in the Uk previously but it is only in recent years that it has become a problem.
Cause
Thought to be the fungus Splanchnonema platani, this was formrly known as massaria platani
Symptoms
Dead strips of bark run along the top of the branches, often making it difficult to see in older trees.
Smaller branches may die within a year or so.
Flaking bark which may also expose an orange coloured sap.
Branches may decay and fall away completely within a few months.
The fungus is widespread in southern USA, it appears to only cause minor damage in warmer mediterranean climates. Symptoms of the disease have been found in mainland Europe.
Research is still ongoing to decipher if the disease is caused by splanchnonema platanior or if in fact subsequent infections.
In order to import Platanus hispanica you must have a plant passport, all imports must be notified to the UK plant health authorities so inspections can be carried out.
For more information on Massaria disease please visit Forestry.gov