MISSISSIPPI STATE -- Just about anyone with a yard knows the frustration of trying to eliminate fire ant colonies, and now is the time of year to fight the battle again.

Making a broadcast application of an effective fire ant bait between Labor Day and first frost is the best way to get rid of existing colonies and prevent many of next spring's mounds.

"These fire ant treatments must be applied broadcast, rather than as individual mound treatments, in order to control the many small colonies that do not yet have visible mounds," advised Blake Layton, Mississippi State University Extension Service entomologist. "Many small colonies are just being established by recently swarmed queens. These small colonies won't be visible now, but they will quickly become obvious next spring."

On small- to moderate-sized lawns a small, hand-powered spreader should broadcast the bait effectively. Be sure to read each product's usage instructions to obtain the desired result without wasting time and money on excess bait.

"Most fire ant baits are used at a rate of 1 to 1.5 pounds per acre, but there are exceptions," Layton said. "That's not a lot of material, so it's important not to be too heavy-handed when applying baits. With most spreaders, you'll want to start with the lowest setting possible."

Foraging worker ants will collect the bait granules and carry them back to the colony, where they will be shared with all members of the colony, including the queen. Baits are designed to be slow-acting to allow time for the insecticide to be dispersed through the colony.

"Only purchase the amount of bait needed for this season, and if you have any bait left over, wait a few days and re-treat the most sensitive sites in your lawn," Layton advised. "The oil in the baits tends to go rancid over time, and rancid bait is not attractive to ants, so you don't want to save it through the winter."

Some recommended fire ant bed treatments include Award Bait (fenoxycarb), Distance (pyriproxyfen) and Ascend (abamectin), all of which should be applied at a rate of 1 to 1.5 pounds per acre. Amdro Bait (hydromethylon) and Extinguish (methoprene) are labeled for application to pastures and rangeland, as well as lawns.

Other recommended bait products include Justice Bait (spinosad), Come & Get It Bait (spinosad) and Chipco FireStar (fipronil).

Avoid applying baits immediately before or after irrigation or rainfall. "If rainfall occurs within six hours or so after baits were applied, it is probably a good idea to re-apply," Layton said.

"After completing your fall bait application, be sure to clean up that spreader and put it where you can find it again next spring," Layton added. "Fire ant populations should be low next spring as a result of this fall treatment, but if you want to 'hit 'em while they're down,' go ahead and make another application of bait as soon as the soil temperature warms to 68 to 70 degrees."