Fire Ants in Your Yard? UT Extension Offers Control Recommendations

Painful Pest Can Be Eliminated Using the Two-Step Method

JACKSON, Tenn. – Fire ants are a common nuisance in Tennessee lawns, infesting residential neighborhoods, schools, playgrounds, golf courses, parks and more. University of Tennessee Extension is offering control recommendations to help keep these painful pests from ruining your summer fun.

“Fire ants are easy to disturb, and their stings can cause anaphylaxis if someone is allergic,” says Kim Brown, UT Extension specialist. “To keep you and your community safe, we encourage using the two-step method of fire ant management.”

For step one, broadcast applications of bait-formulated insecticides should be conducted once in spring and again in fall to control colonies before they become established. Hand-held applicators can be used to distribute bait evenly across lawns, suppressing mounds by up to 90% when used according to label directions.

“Fire ant bait has low rates of insecticide and no residual activity. If you have children or pets, you can use this method in your yard and still enjoy being outdoors. However, if colonies are still present after seven to 10 days, proceed to the second step,” says Brown.

For step two, remaining colonies should be treated individually by sprinkling bait one to three feet around the mound. Both broadcast applications and individual treatments should be conducted while ants are foraging or actively leaving the mound in search of food. To determine if ants are foraging, place one to two tablespoons of bait or a small amount of canned tuna, hot dog, an oily potato chip or other greasy foods nearby. If these samples attract fire ants within 30 minutes, it is an ideal time to apply.

“Foraging activity slows when temperatures drop below 65 degrees Fahrenheit or rise above 90,” says Karen Vail, professor and Extension urban entomologist. “In the summer, late afternoon or early evening is a good time to treat mounds. Do not mix bait with other materials or use outdated insecticides, anything older than two years or not stored in an airtight container must be replaced. Once opened, stored bait can become distasteful to ants over time, so only purchase the quantity needed for the current application. It is also important to apply when grass is dry and rain is not expected, ensuring the ants can easily bring bait back to the nest.”

Flammable substances like gasoline are not recommended for fire ant control, as they pose safety risks to the user and can contaminate the soil. Home remedies, such as large quantities of boiling water, can eliminate mounds approximately 60% of the time, particularly on cool, sunny mornings when ants are near the surface. However, in addition to potentially harming the applicator and surrounding lawn, boiling water often does not kill the queen and instead causes the colony to relocate.

“In addition to baits, other individual treatment options for step two include drenches, which are diluted liquid concentrates poured on top; dusts, which are powdery insecticides sprinkled across the mound; and injectable products, which are inserted directly inside. Regardless of the product you choose, always follow the label instructions and apply only the recommended amount,” says Brown. “The colony should die off anywhere from days to weeks later depending on the product selected.”

For more information on fire ant control, please visit fireants.tennessee.edu or contact your local county Extension office.

The University of Tennessee Institute of Agriculture is comprised of the Herbert College of Agriculture, UT College of Veterinary Medicine, UT AgResearch and UT Extension. Through its land-grant mission of teaching, research and outreach, the Institute touches lives and provides Real. Life. Solutions. to Tennesseans and beyond. utia.tennessee.edu.