According to the Bifen IT
product label: Fire Ant control is optimized by combining broadcast applications that will control foraging workers and newly mated fly-in queens with mound drenches that will control existing colonies. If the soil is not moist, then it is important to irrigate before application or use a high volume of water for the application. Apply broadcast treatments at 0.5 to 1 fluid oz. per 1,000 square feet. You can dilute the recommended amount of Bifen IT in 1-5 gallons of water. Use enough water to penetrate thatch or sod. Treat mounds by applying 1 oz Bifen IT Professional per mound in 1 to 2 gallons water by sprinkling the mound until it is wet and treat 3 feet out around the mound. Use the higher volume for mounds larger than 12”. It is recommended that you use a broom handle to poke down through the center of the mound to allow the solution to penetrate. For best results, apply in cool weather (65 - 80˚F) or in early morning or late evening hours