07/31/2026
Great information on bacterial wetwood!
Why is my tree âbleedingâ white foam? Weâve had several calls this week!
The White County Extension Office has received several calls and text messages this week about trees oozing a white, foamy substance from the trunk or large limbs. While it may look alarming, this is often slime flux, also known as bacterial wetwood.
Slime flux occurs when naturally occurring bacteria inside the tree ferment sap. As pressure builds, the liquid is forced out through a crack, pruning wound, or other injury. When the sap reaches the outside of the tree, it may appear dark, wet, bubbly, or even foamy like the photo below.
You may also notice flies, beetles, ants, or other insects gathering around the ooze. Donât worryâtheyâre attracted to the sugary, fermenting sap and are not the cause of the problem.
What should you do?
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Keep the tree watered during extended hot, dry weather.
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Apply 2â3 inches of mulch around the base of the tree (but keep it away from the trunk).
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Avoid wounding the trunk with mowers, w**d eaters, or unnecessary pruning.
What should you NOT do?
â Donât drill holes into the tree to âdrainâ the sap.
â Donât paint or seal the wound.
â Donât spray insecticides or fungicides on the affected area.
In many cases, otherwise healthy trees can live with slime flux for many years. The best treatment is reducing stress and maintaining good overall tree health. However, if you notice extensive dieback, large dead limbs, or have concerns about the treeâs safety, it may be time to have it evaluated by a certified arborist.
If youâre seeing something unusual on your trees and arenât sure what it is, feel free to contact the White County Extension Office. Weâre always happy to help identify problems and recommend the best course of action!