Fire ants can be easily identified by the mounds they build.

“They typically like building their mounds in areas that are disturbed, such as where two different types of turf come together or along curbs,” says Janis Reed, Ph.D., board-certified entomologist and technical services manager for the pest control division at Quali-Pro. “Most people know they have encountered fire ants because they got stung by one.”

Unlike those built by other ant species, fire ant mounds do not have a center; instead, they appear as flat or dome-shaped sand that has been “worked,” according to Rakim Turnipseed, Ph.D., product development manager, insecticides, for FMC Professional Solutions.

Mounds can be 1 to 2 feet across and as high as 1.5 feet.

“If the mound is disturbed with a stick or another long object, fire ants will emerge rapidly in large numbers and travel vertically onto the object, a behavior not typically exhibited by other ant species,” Turnipseed says.

How to ID

For those who dare to take a closer look, fire ants typically sport a reddish/brown color. They have two nodes between the thorax and gaster, 10-segmented antennae and a two-segment club at the end of each antenna. It’s important to avoid getting too close to the female fire ants, which can sting.

The pests mostly dwell in southern states and are most active after rain. During the winter, they reside deeper in the soil, but because they mostly thrive in warm-weather states, fire ants are active all year long.

“Fire ants can build mounds in most types of soil, even after rainfall as they prefer to work with and maneuver through damp soil,” Turnipseed says. “They are quite resilient after flooding caused by rain as they have the ability to float until they reach dry land and build a new mound almost overnight.”

Damage control

The damage fire ants cause is two-pronged, Reed says.

“There’s an aesthetic damage up through the turf due to their mounding activities,” Reed says. “There’s also the damage to a worker who may reach down to pick up an object and instead get five or six fire ants on them and be stung.”

To help keep fire ants under control, Reed recommends putting out fire ant baits both at the beginning and end of their active season.

“You can cover a large area without a lot of product,” Reed says. “It pays to manage fire ants over time rather than just when they become a problem.”

Generally, fire ant baits should be used when temperatures are between 70 degrees F and 90 degrees F, Turnipseed says.

“They are easy to apply and don’t take any specialized equipment,” Reed says. “The most effective time for bait applications is in the fall because you’re attacking those fire ants when they’re going into the lean winter months. If you can knock down numbers at that time of year, you can get the best control.”

Additionally, regularly mowing lawns can knock down some mounds and cause them to be relocated, but this will not likely reduce the number of mounds, according to Turnipseed.

Reed says the main cultural practice to help control fire ants is to keep the turf healthy.