05/03/2025
Spotted this week: Kretzschmaria deusta
This week I came across Kretzschmaria deusta, also known as the cinder fungus, on a beautiful mature beech tree. This fungus is typically found around the base of trees, often nestled in the buttress roots.
The tree I inspected was showing clear signs of decline, with a high proportion of deadwood, particularly in the crown. After a closer look around the base, I identified the presence of Kretz.
While I’ve mostly observed this fungus on beech trees, Kretzschmaria deusta can also affect other broadleaf species like horse chestnut and sycamore. In spring, it starts with a whitish appearance, gradually turning grey before becoming charcoal black by late summer.
The impact of Kretz is notable—it can lead to the rapid decline of large, mature trees. Deadwood in the crown is often one of the first indicators that something is amiss. If you're working with trees, it's essential to look out for signs like these and investigate further.
Early detection is key to understanding and managing tree health.
Unfortunately, if there is a target within falling distance of the tree, there is not a lot that can be done to manage the tree moving forward. The fungus can make the wood very brittle, often leading to ceramic-like failure at the base of the tree, increasing the risk of collapse. In these cases, careful monitoring and, in some instances, tree removal may be necessary for safety.
If you have spotted any warning signs in your tree, please drop a comment or message and we can take a look.