Answer: It's never a good sign when the bark is splitting on the trunk, or even the branch of a tree. Once a wound like this occurs, disease causing bacteria and insects can enter and threaten the life of the tree.
Splitting can be caused by sunburn, freezing temperatures, or physical injury. If the split is clean, it will heal over time, all on its own. If the bark is jagged, or sap is oozing, clean the wound out with a sharp knife to remove dead material. A healthy tree will callous over an injury in a matter of months to years, depending upon the size of the wound.
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