Fire ants commonly infest lawns, schoolyards, athletic fields, golf courses and parks, where they pose a medical threat to people and animals. Their mounds also detract from the appearance of the landscape and can damage lawn care equipment.
This program suppresses ants in ornamental turf and non-agricultural lands, including roadsides. It is also suitable for pasture and rangeland if the products selected are specifically registered for use in these sites. Similarly, an "organic two-step" program can be implemented using a bait and a mound treatment combination considered "organic" or using products certified by the Organic Materials Review Institute (OMRI). This approach is best suited to medium-sized or large areas, and the cost is moderate. It is not suggested for use in previously untreated areas with few fire ant mounds (20 per acre or fewer, or 0.46 or fewer per 1,000 square feet). Some bait products may affect native ants that compete with imported fire ants. The goal of this program is to reduce fire ant problems while minimizing the need to treat individual mounds.
The two steps involve: 1) broadcasting a bait product (see the section on Baits in Fire Ant Treatment Methods), followed by 2) treating nuisance mounds with a faster acting individual mound treatment or with a mound re-treatment of the bait.
Repeat the bait application when ants re-invade the area and mound numbers reach about 20 per acre or exceed the tolerance level for a situation. Bait products do not protect against reinvasion by ant colonies from surrounding land or by newly mated queens. Ant populations can fully recover within 12 to 18 months of the last bait treatment. Low-lying, moist and flood-prone areas are more prone to re-infestation.
This approach is best used in small areas of ornamental turf (usually 1 acre or less) where there are fewer than 20 to 30 mounds per acre or where preservation of native ants is desired. This program selectively controls fire ants, but rapid re-invasion should be anticipated. It generally requires more labor and monitoring than other programs, and is not suggested for large or heavily infested areas.
This program eliminates many ant species in treated areas and it reduces re-invasion of treated areas as long as the contact insecticide remains effective. However, these products are more expensive, use more insecticide, and have greater environmental impact than other methods. This approach is frequently used by commercial applicators for treating ornamental turf. Long-residual products that contain a pyrethroid usually work most rapidly. Fipronil granular products eliminate ant colonies more slowly but have longer residual effects.
Any of the three programs can be mixed and matched within a managed area where different levels of fire ant control are desired. On golf courses, for instance, Program 3 might be suitable for high-use areas such as putting greens and tee boxes. In fairways and rough areas, Program 1 might be sufficient. On athletic fields, where as many ants as possible must be eliminated, Program 3 should be used, and the program should begin early enough to attain maximum suppression by the time the field is in full use. People with severe allergies to fire ant stings should follow Program 3 for their lawns or use a bait on a calendar schedule. For grounds around schools, day care centers, mental health facilities, and other sensitive sites, broadcast application of a fire ant bait product twice per year is one of the least-toxic methods of control. Control should be monitored with routine surveillance for re-invading ant mounds that need to be treated.
In some states, special regulations may govern the selection and use of fire ant products on school grounds. In Texas, for example, all pesticide applications must be made by licensed applicators. Schools in Texas are encouraged to use botanical, microbial, or insect growth regulator insecticides because of their extra high margin of safety. Appropriate bait treatments for Texas schools include formulations containing abamectin, spinosad, pyriproxifen or methoprene. Good first choices for mound treatments around schools and other sensitive areas include botanical insecticides containing pyrethrins, d-limonene or other natural compounds such as spinosad. For the greatest degree of safety, use only formulations that are washed immediately into the mound and leave minimal surface residue. Laws governing pesticide use in and around schools are subject to change each year. If in doubt about laws governing pesticide use around schools in your state, contact your state’s lead agency for pesticide regulation. State-by-state summaries of pesticide laws can be found on the Internet at NPMA Pestworld.