Controlling Fire Ants in Pastures
Avoid forage losses, personal injury and equipment damage by controlling fire ants.
In 2003, the USDA estimated that the annual cost of problems caused by imported fire ants in agriculture was $750 million, with $38 million in losses to livestock. A relatively low amount of losses occur in direct livestock losses. The primary economic losses in livestock production associated with fire ants are due to reduced forage availability, personal injury and damage to equipment used for hay production.
| Table 1: Products Labeled for Fire Ant Treatment in Pastures
|
|
| Amdro Hydromethylnon (Toxicant) | Broadcast bait companion animals and animals not intended for food or food product |
| Amdro Pro Hydromethylnon (Toxicant) | Broadcast bait labeled for pastures and hayfields. 12-hour REI |
| Seige Pro Hydromethylnon (Toxicant) | Broadcast bait labeled for pastures and hayfields. 12-hour REI |
| Extinguish® Methoprene (IGR) | Broadcast bait, slow acting, may give longer suppression of population. Can be “tank” mixed with other baits |
| Extinguish® Plus Hydromethylnon + Methoprene | Broadcast bait |
| Esteem® Pyriproxifen (IGR) | Broadcast bait labeled for pastures, rangeland and a variety of vegetables |
| Justice® Spinosad IMT | Only in pastures |
| Sevin® 80S Carbaryl IMT | Drench only |
Source: Clemson Cooperative Extension. Compiled by Timothy S. Davis. |
|
The estimated cost of broadcast applications of fire-ant baits approved for use in pastures is $10-$15 per acre. The cost of the products alone is commonly $10 per pound (lb.), and recommended application rates vary from 1 to 1.5 lb. per acre. Total cost per acre would be $15-$20 per acre, including labor and equipment.
An evaluation of the farm, and mapping the location of problem fire ants may lead to the conclusion that the greatest impact would be obtained by a partial treatment. Start with critical areas such as farm yard, working areas, equipment storage areas, around gates and handling facilities. Only treat pastures and hayfields that will likely present a problem. This would reduce the overall cost of fire-ant control per acre.
Despite the problems they cause, fire ants also provide benefits as predators of agricultural pests. Researchers have observed a gradual decline in tick populations as fire-ant numbers have increased. Field studies conducted in Louisiana in 1972 clearly demonstrated significant fire-ant predation on ticks. Fire ants also were identified predators of the immature forms of the horn fly, which is one of the major economic pests of livestock in the United States. As such, it would be practical to accept the inevitable presence of fire ants in pastures, maintain their beneficial aspects and manage their populations below economic impact levels.
Editor’s Note: Morris Warner is a Clemson Cooperative Extension county agent for Oconee County. This article was reprinted with permission from CU in the Pasture, the Clemson Livestock & Forages Team newsletter at www.clemson.edu/extension/livestock/
newsletters/ivestock_newsletter_05_2015.pdf.