Answer: If you have fire ants, use Amdro, Award, Logic or similar granule bait preparations. These don't kill instantly but give the workers a chance to take the bait back to the mound as food where its pesticides disrupt reproduction by hormonal control over queen ants. Fire ants forage out of underground tunnels that lead all around within 100' of a mound. Therefore use a broadcast spreader to evenly distribute the bait over your yard.
Broadcast these granules all over the infested area on a nice day so that the fire ants get all of the bait. The worker ants will take the granules into the mound. Be patient because these baits take about 6 weeks to take effect; the mound will die. You should have control for many months and additional spot applications of the granule baits when you see small mounds restarting should keep things tolerable (or with just a mound or two, boiling water poured on the mound when it comes up after a rain is very effective).
If you coordinate with neighbors and use the same treatment area-wide on the same week, you will reduce the rate of re-invasion.
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