If you want to cool off your fire-ant problem, do it now.
The ground temperature is just right, and if you do what the experts recommend, your property could be practically ant-free until fall.
"It's time to begin treatment when the soil temperature is between 65 and 75 degrees," said Sid Mullis, coordinator for the University of Georgia Extension Service office for Augusta-Richmond County. "The temperature in the Augusta area has been fluctuating between 65 and 72 degrees the last couple of weeks, and the rain has made this the ideal time to treat."
The best treatment is a two-step process, beginning with broadcasting a bait, such as Amdro, Award, Ascend or Distance, which the ants take back to the mound, Mr. Mullis said.
Use a pound to 1 1/2 pounds per acre. The average lawn will take a half-pound, he said.
"If they broadcast this bait in the spring and fall, they will get anywhere from 75 percent to 95 percent control," Mr. Mullis said.
A week after broadcasting the bait, treat surviving colonies with an insecticide. One of the best treatments for individual mounds is acephate, commonly sold as Orthene, he said.
Stan Diffie, research coordinator with the Department of Entomology at the University of Georgia Coastal Plain Experiment Station in Tifton, also recommends the two-step process of baiting and then treating remaining colonies.
"If you have some money, they're pushing a product called Over 'N Out, a granular insecticide that you water in," Mr. Diffie said. "Do the bait, but if I were rich, I'd do the granular. Wait a week and treat the remaining live colonies."
Over 'N Out contains fipronil, a compound used in Frontline topical flea and tick control for cats and dogs, REGENT corn insecticide and ICON FS rice insecticide, according to Garden Tech, makers of Over 'N Out. A 10-pound bag costs $20 to $30 and will cover 5,000 square feet. One application will last from spring to fall, Mr. Mullis said.
"Golf course superintendents have been using it for years for mole-cricket control, so it will probably add benefits for homeowners with a mole-cricket problem," he said.
Up to a quarter of a million fire ants may live in one large mound, such as those found in pastures. Mounds in residential yards seldom get that large, Mr. Diffie said. Ant colonies typically extend three feet down but can go farther, he said.
"That's why it's so hard to kill them with some of these drench materials, the products you mix with water," he said. "If they're way down in the ground, it may not reach them."
The advantage of using a drench material is it kills the ants immediately. The disadvantage is the hassle of carrying water if you have several mounds to treat.
"You can get tired of carrying water, since the recommended application is two gallons on each mound," Mr. Diffie said.
If you want to keep fire ants out, you need to use the two-step treatment twice a year, preferably in the spring and fall, since that's when they're most active.
"Don't think you can treat them once, and that's enough," he said.
Mr. Diffie is involved in biological control work at the experiment station in Tifton that could drastically reduce or eliminate the pests.
The USDA has imported a disease that affects only fire ants, and studies are under way to see if it will spread to other ants, he said.
An experiment is also under way in Tifton to eliminate fire ants using a "decapitating fly."
"We've also released a fly that lays an egg on the neck of the ant, and when the larvae hatches it eats the inside of the fire ant's head, which then falls off," Mr. Diffie said.
The flies are very expensive, and the study is still in the experimental stage, so don't look for them as a solution to your fire-ant fight anytime soon, he said.
Fire ants have infested 276 million acres of land and continue to invade about 6 million new acres each year.
Fire ants are adapting to cooler climates and, as a result, now infest 16 states, spreading as far west as California and as far north as Delaware.
More than 30 million Americans live in fire-ant country.
Each year, 25,000 people require medical attention for allergic reactions to stings, ranging from rashes to anaphylactic shock, according to the American Academy of Allergy, Asthma and Immunology.
Fire ants first came to the United States on cargo ships from South America in the 1930s.
Reach Sylvia Cooper at (706) 823-3228 or firstname.lastname@example.org.