I am sorry for this delayed reply to your gardening question. The spring rush has brought a deluge of questions and we are working hard to catch up!
The ants are not causing a problem for the plum tree. The tree is most likely suffering from some type of root problem or perhaps borers in the trunk and main branches. Look for signs of sawdust coming from holes in the trunk or branches sometimes with sap coming out of the holes too.
I suggest you call your County Extension Office to see if they can diagnose the tree from a picture or a sample you bring in. They can then know which product to recommend if a spray is needed. Their contact information is:
1262 Government Circle, Ste 40
Jonesboro, GA 30236-5905
Thanks for the question. Best wishes for a wonderful gardening season. Please stop in again soon!
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