Use a Boric Acid/sugar solution.


I have a grease ant problem and I had a bit of success with boric acid and
purina. They stopped eating purina.
Then they went after the canned stuff.
I mixed up some of the "gravy" in the bottom of the can with boric acid. They
managed to eat the gravy and LEAVE the boric acid!!!

I suppose those yankee ants are easier to kill that Florida ants.
These guys even shake off Raid ant and roach spray. If you hit them with the
liquid it kills them but as soon as it dries they walk over it with impunity.
Dursban seems to get them but only if you make an unbroken perimeter. If they
find a 1/4" spot you missed it becomes an ant highway.