There are numerous ways to manage fire ants, but they are often broken into two categories- broadcast treatments and individual mound treatments. Individual mound treatments are used to treat one mound at a time and can be labor intensive and may result in more pesticide being spread into the environment. Broadcast treatments spread product (granular or bait) over a large area.
Individual mound treatments include pouring boiling water onto the mound, using insecticide mound drenches, spreading insecticide granules onto the mound and watering them in, sprinkling insecticidal dusts on top of the mound or using bait-formulated insecticides around the perimeter of the mound. There are also many “home remedies”, but be advised that many of these do not kill fire ants. Many home remedies make the fire ants move to a new location (often 1-2 feet away), but do not kill the ants.
Bait-formulated insecticides most often consist of a de-fatted corn cob grit coated with soybean oil; the soybean oil is where the active ingredient (what kills the pest) is dissolved. Worker ants collect bait as a food source and take it back to the colony to share with other ants, including the queen. Depending on the active ingredient, the bait may cause the queen to die or be unable to produce viable eggs, which gradually kills off the colony. When using baits, results are often slower to observe when compared to individual mound treatments, but can provide 80-90% suppression for 12-18 months. A bonus to broadcasting baits is that the amount of active ingredient is generally very small, which places less chemical into the environment.
With any pesticide treatment, read and follow all label instructions. Make sure to water in the pesticide if the label instructs to do so. Failure to water in chemicals when recommended by the label does an inadequate job of killing the ants. Baits should not be watered in or used before a rainfall event; baits will not be picked up by ants if they get wet.