Trees suffering from disease

Trees can be affected by a wide range of different pests and diseases. Although many are not hugely harmful to the tree or yourself, you may find the following information useful. Further Government advice is available.


If you see fungus (it can look like toadstools, brackets or large mushrooms) growing on the tree, particularly at the bottom, please report this to us. You can use the other general enquiries form or call 020 8854 8888.

Brown leaves on a horse-chestnut

If you are concerned about a horse-chestnut that has leaves that have turned brown, it has probably been infected by a leaf-mining moth. Although this affects the visual appearance of the tree it does not make the tree unsafe and is not harmful to public health.

Stem or branch bleeding

Some trees, particularly Horse Chestnut, Birch and Oak may show signs of stem bleeding which may result in individual branch or even whole tree death. If a tree is showing signs of such decline please report it to us using the other general enquiries form or call 020 8854 8888.

Oak Processionary Moth

This particular caterpillar is spreading on Oak trees across London. For more detailed information on this disease please see our dedicated page.