Question
I had a very  healthy Cherry Tree for the past 12 years until this spring.  I noticed that it did not bloom at all and then shortly after the leaves began to appear black(dried and dead).  I live in south Alabama and this past winter was very mild...we had 2-3 frost advisories which is pretty normal every year.
The only thing that varied this year was a large ant mound at the base of the tree.   Could the ants have compromised the tree?  I noticed red sap weeping from the lower part of the trunk.  Is it too late to save the tree?  
Thank you for taking your time with my question.
Sincerely,
Christine

Answer
Hi Christine:

I suspect that the ants have only a minor role in the tree health.  The weeping sap that you observed may indicate insect activity within the tree a.k.a. borers.  These insects actually tunnel inside the wood of the tree.  Enough tunneling and numbers of individuals may indeed affect the tree's health.  Insecticides have a difficult time getting to the insect once they get inside the tree.  Most are effective as preventatives.  Consider contacting your local county Agriculture Extension office (usually located in the county courthouse) to arrange a "house call" in order to provide you with an on site evaluation of the tree health.

Regards
Steve