First, is it worth treating your pasture at all? If the answer is yes, there are several baits that can be broadcast for imported fire ant control in pastures. These baits cost about $10-15 per acre. The cost of labor and equipment needed to apply the bait also must be considered. Baits containing hydramethylnon (Amdro Pro), pyriproxyfen (Esteem), (s)-methoprene (Extinguish), or a mixture of hydramethylnon and (s)-methoprene (Extinguish Plus) are currently labeled for use in cattle pastures or pastures for companion animals. In addition to the above materials, Award fire ant bait (containing fenoxycarb) can be applied to pastures grazed by companion animals such as horses. If you are treating more than 100 acres you might want to consider aerial application of fire ant bait. A mound drench containing carbaryl (such as Sevin 4F, Sevin XLR, and Sevin 80S, that are labeled for use in pastures) can be applied to individual mounds. Fire ant baits can also be used as individual mound treatments, but do not work as quickly as carbaryl. It would not be economical to treat very many mounds individually, because of the cost of the materials and labor involved. More information can be found in Management of Imported Fire Ants in Cattle Production Systems. See also: FAQ #824: Which bait do I use?
To customize the needs of your operation, use the Fire Ant Decision Tool, a module that helps cattle ranchers develop their own site specific fire ant management plan.
Note: A particular fire ant control product may not be registered (legal to use) in every state. This is especially true if 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.
