Most currently-available fire ant baits work very well when applied according to the label instructions. The key to using baits is patience. If you use a bait product and apply it properly (use fresh product, apply when ants are foraging for food when temperatures are 65 to 95 degrees F), a broadcast application should give 80% to 95% control. Choose a bait based on cost of the bait, how soon you need to have fire ant control, and how long you want to wait between bait applications. The way a fire ant bait works depends on the active ingredient in the bait. Some baits contain an insecticide that kills all ants that ingest a sufficient dose, including the workers and the queen. Baits containing a synthetic insect hormone called an IGR or Insect Growth Regulator reduce the production of viable eggs and re-direct larval development to prevent production of new worker ants; they do not directly kill the queen or the adult workers. Each fire ant bait acts somewhat differently, so read the label to determine the right way to apply each product and how much product to use. Currently, eight insect control chemicals are used as active ingredients in fire ant baits: abamectin, fenoxycarb, fipronil, hydramethylnon, indoxacarb, s-methoprene, pyriproxyfen, and spinosad.
Broadcast-applied granular fire ant baits include:
Fast-acting baits: Products that eliminate fire ant colonies within a 3 to 10 days. Nothing, however, is left in the environment after a few days to prevent re-invasion of treated property, either by mating flights or ground-migration of ant colonies from adjacent untreated areas.
- indoxacarb, sold as Spectracide Once N Done and Advion; I
Faster-acting products: The first fire ant workers will die in about 2-3 weeks, but it can take 4-6 weeks to kill achieve maximum reduction of ant colonies (Note: when used as an individual mound treatment). Insecticide-based baits usually provide several months of control depending on re-invasion (see above).
- hydramethylnon, sold as Amdro, Amdro Pro, Amdro Fire Ant Bait Yard Treatment, Probait;
- spinosad, sold as Fertilome Come and Get it, Ortho Fire Ant Killer Bait Granules, Penn-Kill Fire Ant Killer Bait, Southern Ag Payback Fire Ant Bait, and Green Light Fire Ant Control with Conserve;
- fipronil, bait formulation sold as Maxforce FC
Slower-acting products:
- abamectin, sold under the trade names of Ascend, Advance 375 A Fire Ant Bait, and Varsity; the active ingredient is technically a nerve poison that performs similar to IGR products (see below) when broadcast-applied, but works faster when applied as an ant mound treatment.
Slower-acting, longer-lasting bait products containing IGR's (Insect Growth Regulators): These materials act quickly to prevent new fire ants from developing, but it takes longer for the existing workers to die. Results from broadcast applications of fenoxycarb, and pyriproxyfen can be seen in 6-8 weeks. S-methoprene takes 8-12 weeks. Insect growth regulators usually provide 6-12 months of control. It all depends on how soon new fire ant queens or ground-migrating colonies re-invade the area.
- fenoxycarb, sold as Award and Hi-Yield Logic;
- s-methoprene, sold as Extinguish;
- pyriproxyfen, sold as Distance (urban uses)and Esteem (agricultural uses).
Combination products: If you want to have faster control than you get with an IGR (Insect Growth Regulator), yet longer-lasting control than you get with an faster-acting insecticide-based bait, you can mix the two types of baits together at half rates.
- Extinguish Plus is a commercially available mix of hydramethylnon and s-methoprene.
Product availability: There are a number of products available to at retail outlets for homeowner use (see fact sheet ANR-175A). However, not all bait products are sold at retail stores. If you are having trouble finding a fire ant bait, try looking at big-box stores, hardware stores, home and garden centers, home improvement stores, farmers' co-ops, pesticide distributors, and do-it-yourself pest control stores.
Be sure the use site is listed on the product label: Amdro Pro, Esteem, Extinguish, and Extinguish Plus can be applied to active cattle pastures and hayfields. Extinguish can be used on most cropland and vegetable plots. Fertilome Come and Get It Fire Ant Killer and Green Light Fire Ant Control with Conserve can be used on home garden plots, provided they are less than 1 acre. Esteem can be used by commercial growers in many tree fruits and nut orchards, as well as in certain vegetable and fruit crops. Note: A particular fire ant control product may not be registered (legal to use) in every state. This is especially true it you live in a western state with very few fire ant-infested counties. What does this mean? Purchase your fire ant control material in the state that you live in, and make sure you find fire ants on the label of the pesticide. Your county Extension office should be able to help you confirm if a particular pesticide is registered in your state.
Broadcast application: The most effective way to apply bait is to broadcast it. Small areas can be broadcast using a hand-held seed spreader. Larger areas can be treated using seeders with a larger hopper and a wider swath width. A fire ant bait has three ingredients. The insect control chemical (called the active ingredient) is dissolved in soybean oil, which attracts the ants. The oil is absorbed onto a corn-based carrier, allowing the bait to be easily spread. Fire ant workers quickly pick up the bait, moving the active ingredient into the fire ant colony and away from other organisms. Fire ant baits, when applied as directed, are considered to provide minimal risk to the environment because they contain such a small amount of active ingredient. The ants extract the toxicant-laden oil and feed it to other members of the colony. Because the active ingredient is relatively slow-acting, there is ample time for the material to be fed to the queen. Baits are the most effective method to keep the queen, the heart of the colony, from reproducing. Baits also effectively treat mounds not large enough to be seen. For more information see "Broadcast Baits for Fire Ant Control" and "The Latest Broadcast on Fire Ant Control Products" . See YouTube videos of ground and aerial application.
Target specificity: When imported fire ant control is desired, selecting and applying a bait in such a way to assure that it is targer-specific will maintain other ant species in the fauna of the treated area to help provide biotic resistance that may help prevent imported fire ant resurgence. Fire ant bait products are formulated specifically for the targeted red, black or hybrid imported fire ant species. In areas where these exotic invasive fire ants are prominent (e.g., more than 20 ant mounds per acre), these surface-dominant foraging fire ants out-compete non-target ants for the broadcast applied bait. However, where fire ant population levels are low, non-target ants attracted to the soybean oil formulation may be affected by the treatment.
The food lure in conventionally-formulated granular fire ant bait products' formulations (soybean oil) is not attractive to many other pest ant species in and around the home, particularly to sugar-feeding ants. One bait product, Amdro Ant Block containing hydramethylnon, has been modified with the addition of sugar to make it attractive to a wider array of pest ant species such as the Texas leaf-cutting ant. Another granular ant bait, Advance Carpenter Ant Bait containg other proprietary attractants, making that bait attractive to other ants such as carpenter ants and Rasberry crazy ants. Still another ant bait, MaxForce Professional Insect Control Granular Bait, is formulared on ground silkworm pupae, a protein, making it attractive to a other pest ant species. Other ant bait products are available including liquid or gel baits formulated to attract these other ants. Look for names of ant species on the product label to assure that the formulated product may work on the target species.
