I had to pull regular fire ant duty to keep them out of the yard in Mississippi. Once I spotted a mound, I filled a 2 1/2 gallon bucket up with water and set in on the stove. Once it was boiling, I carried it out to the mound. Fire ants will swarm out of the ground at the least provocation.
Boiling water always worked. And the dead grass in the cooked spots didn’t have to be mowed.
AMDRO