Wetwood Infected Bleeding Trees: Why Do Trees Ooze Sap

By Kathleen Mierzejewski

Older trees end up growing in adverse conditions or conditions not perfect for that particular tree. This just happens without any cause. The tree becomes too large for the area it is growing in, or perhaps at one point it received nice shade and now is larger and gets full sun. The soil becomes old and unconditioned and doesn’t nourish the tree like it used to.

All of these things can cause a tree to start showing signs of bacterial wetwood. Bacterial wetwood (also known as slime flux) is not usually serious but can be a chronic disease that can eventually cause the tree’s decline if it isn’t watched.

Why Do Trees Ooze Sap When Infected with Bacterial Wetwood?

Why do trees ooze sap? The bacterial wetwood will cause cracks in the wood of the tree where sap starts oozing out. The running sap seeps out of the cracks slowly and will flow down the bark robbing the tree of nutrients. When you see a tree bleeding sap, you know there is a problem with it, and most likely it is bacterial wetwood.

Usually when you see the a tree bleeding sap and dark bark areas around where the sap is leaking from, it is not very significant except that it ruins the look of the tree. It usually won’t kill the tree until bacteria starts to form. Once this happens, you will see a gray brown foamy liquid that is called slime flux. Slime flux can prevent the cracks from healing and will also prevent the formation of calluses.

When it comes to a tree bleeding sap or slime flux, there is no real cure. However, you can do a few things that can benefit the tree that is suffering from bacterial wetwood. The first thing is to fertilize the trees. A lot of the time the problem is being caused by lack of nourishment. Fertilizing will help to stimulate growth and lessen the severity of the problem.

Second, you can alleviate slime flux by installing plastic drainage or iron drainage. This will help to relieve the pressure from the gas that forms and allow the drainage to happen away from the tree instead of down the trunk. This should also help to alleviate the spread of bacterial infection and toxins throughout the remainder of the healthy part of the tree.

So remember, if you see a tree bleeding sap, it doesn’t mean that the tree is going to die. It simply means it has been injured and hopefully, something can be done about it before the problem becomes chronic.

This article was last updated on

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