Around here is "Chew toy of the Gnat Gods" (A book locally published here in Savannah, Ga) Best way to get rid of fire ants is uncooked Grits. Pour some around the mound....they take it down. After a day or so, add water. The Grits swell up and plug up the mound and most things in it.
In combo with Ampro...they DIE!
BUUUWWWAAHAAAHAAAAAA! (had to add a maniacal laugh!)