It has been widely reported that the large mounds created by fire ants damage pickups, all-terrain vehicles (ATVs), shredders and hay equipment. Mounds cause horses to fall and riders to take bad spills. Other negative fire ant impacts include injury and loss to livestock and wildlife, infested feed and damaged electrical/telephone equipment. Carrying capacity of the ranch is reduced because cattle will not graze in and around fire ant mounds.
So what’s a producer to do? Producers have to determine how fire ant infestations will affect the bottom line while homeowners worry about the ants stinging family members and guests, and the unsightly appearance of mounds on the front lawn.
Effective fire ant control requires a programmed approach, and pretreatment planning is an essential part. Annual economical losses caused by fire ants need to be calculated and compared with treatment costs. The cost of eliminating fire ants from an entire operation may not be justified by economic losses, particularly on large ranches. In this case, the better option is to identify and treat those areas only where control costs are justified. To control costs, fire ant management may be confined to high-traffic work areas, feedlots, hayfields and calving pastures. Treatments can be limited in lesser work areas, infrequent traffic locations and in the back pastures.
One cost-effective and environmentally friendly approach to manage fire ants is called the two-step method. This approach works best in fully infested areas of 20 or more mounds per acre and where there is little or no concern for preserving native ant species. Two-stepping includes broadcasting a bait insecticide over an entire area in the spring between late April to mid-June and in the fall between late August and mid-October. Remaining individual problem mounds are then treated with an approved drench, granule, bait or dust insecticide.
A hand-held seeder or spreader is ideal for broadcast treatments of lawns or other small areas around buildings or equipment. A low-volume applicator mounted on a tractor, the receiver hitch of a pickup truck or ATV is suited for pastures, hayfields and range less than 200 acres. For low-traffic areas, there are skip swath techniques for applying insect growth regulator baits. Two acres are covered with only enough bait for one acre by applying the material on every other swath.
Individual mound treatments, the second step in the two-step program, are generally considered the most labor-intensive and costly treatment methods and they give the shortest fire ant-free period. However, fast-acting methods are the most desirable in some situation, especially where preservation of native ant species such as red harvester ants and other competitor ant species is desired.
Check the pesticide label to ensure the product is registered for pasture use. Although there are many available fire and bait products, only specific ones such as Extinguish Plush, Extinguish and Amdro Pro and Esteem can be applied around animals used for food production. Amdro Pro should not be confused with Amdro when making pasture applications. Under favorable conditions, fire ant colonies multiply rapidly and can eventually engulf the entire ranch. When they appear, it is important to initiate a control program that fits ranch operations.
Source: Kenneth Johnson, Jr., County Extension Agent, Agriculture & NR