University of Maryland Extension

My tree looks like it has a wet bleeding wound on the trunk. What is this?

Carolyn Puckett

Your tree may have a bacterial infection called “wetwood” or “slime flux”.  Wetwood is most commonly found on mulberry, poplar or elm, but can infect many other hardwood trees, such as maple, oak or black gum.  Symptoms are a vertical crack on the bark with bleeding, discoloration, and a foul or alcohol-like scent.  The bleeding liquid is clear at first, but feeding on the fluid by fungi, yeasts, bacteria, and insects can turn the seepage into a smelly, slimy ooze.

The bacterial infection starts in the center or heartwood of the tree and may spread to the sap wood.  Once a tree is infected, it cannot be cured.  The infection is not fatal to the tree, but may weaken the tree somewhat, making it more vulnerable to drought or to other diseases and insects.  While a shunt can be put in the tree to siphon off the fluid, the results are cosmetic only—it does not help the tree. Puncturing the tree or pruning off live growth may even expand the wetwood infection.  You can carefully remove dead bark around the wound to promote drying of the area. 

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