What Are the Treatments for Tree Fungus?

Some tree fungi occur on the surface of the tree and are often harmless; the most harmful fungal infestations occur under the bark.

Tree fungal infections are very difficult to treat. Some fungal infections are minor and don't affect the long-term health of the tree. Others, like Dutch Elm disease, often result in the death of the tree. The best thing to do is to make sure that the tree is healthy enough to resist fungal infections in the first place. However, once a fungal infestation has occurred, there are a few ways to treat the fungus.


Fungal infections can be caused by natural spread or by using contaminated tools and equipment. If you are working with a number of trees and suspect that one or more has a fungus, be sure to thoroughly clean your tools before working on another tree. In some cases, prophylactic treatments can be injected into a healthy tree to prevent fungus from nearby trees from infecting the protected trees. By ensuring that all aspects of the tree's environment are ideal, some trees may be able to naturally resist fungal infestations. It is also very important to seal tree wounds or areas where branches have been removed. Tree bark protects the tree from various diseases, and any breaks in the bark need to be sealed to protect the tree.

Prophylactic Treatments

In areas where a number of trees have been infected by a particular fungus, healthy trees can sometimes be injected with a chemical anti-fungal to help prevent further spread. For example, in areas with Dutch Elm disease, healthy trees can be treated to prevent the spread of the fungus. These treatments last for up to three years. Other tree diseases that can be slowed or stopped by prophylactic treatments include a number of citrus tree diseases and sycamore anthracnose.

Treating Infected Trees

Treating a tree where a fungal infestation has become well established can be difficult and sometimes impossible. In some cases, prophylactic treatments can slow the fungus enough for the tree's natural defenses to take over and kill the fungus. Some Dutch Elm disease injections have had positive effects on trees with heavy infestations of the Dutch Elm fungus.

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