I have not had time to confirm this but it appears to be slime flux or wetwood disease. I have seen this disease on other trees for many years but this is a good picture of this disease symptom.
It is usually non-life-threatening for the tree but in warm weather it can attract flies and sap beetles, insects attracted to the smell of yeast and alcohol.
Read more about slime flux or wet wood by following this link
And this one as well.
Whenever you make any kind of cut into a tree or plant, make sure your knife or pruner has been sanitized and preferably sterilized before you make the cut. I prefer to use alcohol or an open flame but household cleansers such as 409 and others will provide some measure of sanitation.
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| I have not had time to confirm this because the picture was sent to me, but this appears to be slime flux or wetwood disease on African sumac. Great picture forwarded to me by Joy Mandekic. |
Some other pictures of mine of this same disease.
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| I took this picture of wetwood a long time ago and digitized it from a slide. |
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| From Jim Falcone |
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| Also from Jim Falcone |