Fall is a good time to bait fire ants for spring. Most fire ant baits are slow-acting growth regulators and may take six months or more to eliminate colonies. Baits remain the best options for areas larger than an acre or so, according to UGA entomologist Will Hudson.
Many brands fall into two basic groups: those with active ingredients that are toxic to the ants (like Amdro), and those that have insect growth regulators that sterilize the queen and stop development of the immature ants in the colony.
Applied every six months, they often carry a guarantee of “no mounds” if applied correctly, but that doesn’t mean no ants.
Bait treatments cost about $20-30 per acre.
For smaller areas, or where you need zero ants, Hudson recommends a broadcast application of a contact insecticide, such as fipronil products (like Over’n’Out) or those with pyrethoids as active ingredients. Pyrethroids are active ingredients ending in -thrin such as bifenthrin, permethrin, cypermethrin or cyfluthrin. Fipronil will usually eliminate ants for a season, said Hudson, while pyrethroids are shorter lasting, but will give one to four months of control.
Costs range from less than $50 per acre for pyrethroids to more than $150 per acre for fipronil.
A newcomer to the fire ant control market is fast-acting indoxacarb, which is sold as Advion for commercial use and in the Spectracide line for homeowners.