TUPELO • A tiny pest drew a packed audience Thursday at the Lee County Extension Office in Tupelo.
“Yes, You Can Control Fire Ants” was the topic of an interactive video program led by Blake Layton, an Extension professor and entomologist at Mississippi State University.
“We’re getting more questions about fire ants than any other pest right now,” Layton told group. “They’re the most common insect pests of home lawns and they are all over our state.”
Layton gave a brief history of the fire ant, which is not native. The black imported fire ant first showed up through Mobile Bay in 1918 and, in the 1930s, the red imported fire ant made its first appearance. The red ant is more aggressive and has, for the most part, displaced the black ant in the Southeast, he said.
The problem with fire ants – aside from their painful sting – is that, uncontrolled, they can reach a density of 50 to 200 mounds per acre.
“If they’re not controlled, you can just about step from one mound to the next,” he said. “For every big mound you can see, there are a dozen or more smaller mounds just getting started. It takes several months for them to grow big enough to be visible above the grass.”
Fire ants are omnivorous, Layton said. They eat plant and animal material – seeds, dead and live insects and dead and disabled animals. Oddly, the adult fire ant can only eat liquids, so it gathers food and carries it back to the colony to the older larvae. The larvae eat the food, regurgitate it to a liquid form, and share it with the adults. This process of social insects sharing food is called trophallaxis.
“This sharing is the reason baits work so well to eliminate fire ant mounds,” Layton said. “We’ve found the most effective way to eliminate fire ants is with both granular baits and mound treatments. We call it the one-two punch.”
Popular granular baits are Amdro, Extinguish and Advion, he said. Baits are easy, safe, cheap and they work.
“You need to apply these two to four times a year and don’t apply them directly to the mounds,” Layton said. “Broadcast the bait all over your yard, even if you don’t see mounds. All you need is a small amount – 1 to 1 1/2 pounds per acre or about 3 tablespoons per 1,000 square feet.”
Layton uses holidays to help remember when to put bait out. Early spring is the best time to apply fire ant baits because the pests are actively foraging for food.
“I apply bait around Easter,” he said. “I may come back three to four weeks later and do another round. And then I put it out again around the 4th of July and again at Labor Day.”
The bait works because the worker ants leave the underground tunnels in search of food and find the bait granules. They take them back to the colony to feed the young and once the food is shared, it’s just a matter of time before the colony is wiped out.
“It may take two weeks to two months to be effective,” Layton said.
The second part of the one-two punch is using liquid drenches or dry mound treatments to treat individual mounds. Liquid drenches contain bifenthrin, permethrin or spinosad and go by names such as Hi-Yield Bug Blaster and Bonide Eight.
“You can use these on mounds that don’t react to broadcast bait,” he said. “Or if you’ve got a barbecue or the grandkids coming over and you need to kill a mound immediately, this is the way to go.”
The most common dry mound treatment contains acephate and is found in products made by Ortho and Martin’s.
“You sprinkle the acephate on the mound and ants will be gone in five to six days,” Layton said. “It smells terrible, but it works great.”
Layton stressed that persistent prevention is key to successfully ridding your yard of fire ants.
“If you don’t want big fire ant mounds in your yard, you have to treat before you have big fire ant mounds in your yard,” he said.