Camille,
  You asked how to get rid of ants in hives.  I don't have a suggestion for
the existing ants, but here in Texas, fire ants can eat a hive in a day.
Beekeepers put the legs of their hive stands in cans of water with a film
of salad oil on the top.  We don't use motor oil because if it overflows
the petroleum can contaminate ground water.  Vegetable oil gets broken down
(even eaten) in the environment.  We also prune overhanging shrubs so branches
don't touch the hive, this prevents ants from coming in from the top.
Good luck.
Carol

Carol K. Malcolm
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