Plane Wilt

Plane wilt, more correctly called Canker stain of plane, is a highly destructive disease that affects plane trees, and poses a threat to our iconic London plane, a tree widely found in urban environments. 

The causal agent is a fungus native to North America called Ceratocystis platani. It is not currently present in the UK but is known to be killing plane trees in mainland Europe. The fungus can be introduced to trees through wounds, or by root-to-root contact below the ground. It can spread on contaminated tools and machinery, in airborne sawdust and in water. The disease affects the trees’ water and nutrient transport systems and is fatal within 2 to 10 years of infection. 

Canker stain of plane causes sudden canopy dieback and wilting of foliage. This can occur across the whole crown if the fungus enters via the roots, or in discrete areas of the crown if the fungus is introduced above ground. Leaf loss and yellowing may also occur. The disease causes stem cankers which can appear as leopard-spot or flame-shaped lesions with yellow margins visible through the bark. These can be difficult to see and show up more clearly when the bark is wet. Older cankers can appear as vertical cracks in the bark. Under the bark cankers, dark brown staining will be evident.  

For more information on plane wilt, see the resources below.