Originally created 06/30/00

South feels sting of fire ants



AIKEN - Got fire ants?

Then learn to live with them.

It's the answer that nobody wants to hear, but it's the only one researchers can come up with. Fire ants cost homeowners millions each year, send some of them to the hospital and occasionally kill a few.

But they have no natural enemies - except humans, who don't know how to control them. That means they're likely to be around forever, communing with roaches when all other life has disappeared.

"We'll probably never eradicate the fire ant," said Tim Davis, a Clemson University Extension agent. "We can only hope to control them to the point that they're not on every street corner."

Right now, it's hard to find any place in the South that has been spared. Economists estimate the fire ant is a $3.8 billion problem, causing damage in dozens of ways - medical, electrical, structural and economic. Fire ants can ruin crops, and in states that rely on tourist dollars, they're enough to make people stay away.

At airports statewide, ants keep knocking out the flashing lights that line the runways. Each time maintenance crews replace the copper circuit boards, it costs $3,500, Mr. Davis said.

It is thought that fire ants came to the United States in the 1930s as castaways aboard ships from South America. Since then, they've thrived in the South, but Mr. Davis said there is evidence the ants are heading North to cooler climates. They might spread up the East Coast beyond Washington and across the nation to Oregon, Mr. Davis said.

Right now, fire ants are as far north as southern Arkansas, southern Tennessee and North Carolina and as far west as Texas. Recently, mounds were found in Los Angeles, Riverside and Orange counties in California.

Locally, recent rains have brought temporary relief to stunted crops and lifeless lawns, but they also have brought fire ants to the surface from their underground chambers. And with temperatures soaring toward triple digits, they have moved indoors to cooler quarters.

"Now that it's rained, it seems like fire ants are everywhere," said Phil Napier, who owns a hardware store in Graniteville.

He's right. When there wasn't much rain, the fire ants stayed buried where the ground was much softer, cooler and moister. But they've made a grand appearance in recent weeks, and business has picked up at Napier's Hardware.

"I've doubled my pesticide sales," Mr. Napier said. "Customers are complaining that they're everywhere you step and have crawled into their houses. It's a mess, for me and everybody else."

But before homeowners declare war, agriculture experts want weekend yard warriors to know a thing or two about what they're up against:

Don't use bait when forecasters are predicting rain, no matter how slight the chance.

Apply bait when worker ants are searching for food. In the summer, that's usually during the evening and at night. During spring and fall, it's usually in the warmer daylight hours.

To find out if they're foraging, leave a tiny bit of bait next to an active mound. If ants begin attacking the "food" within 10 to 30 minutes, it's a good time to apply. But remember, ants are less active when the soil temperature is below 70 degrees and higher than 95 degrees.

Homeowners in South Carolina spend at least $112 million each year on insecticides, repairs and medical and veterinary care, according to Clemson University. That's not counting what the ants cost businesses, industry, tourism and agriculture. Researchers soon will conduct a statewide survey to figure out exactly how much.

Researchers do know that fire ant stings in South Carolina have increased 34 percent in the past 12 years, according to researchers at Medical University of South Carolina in Charleston.

In 1998, two people died and at least 33,000 sought medical care for stings - estimated to be only about 5 percent of cases, said Dr. Stan Schuman of the medical university's Department of Family Medicine.

Clemson Extension Agent Terry Mathis remembers when a young child died after being stung by fire ants. It's a story he won't soon forget.

"The child was involved in a wreck, and when EMS workers pulled him out of the car, they sat him on top of a mound not knowing it," Mr. Mathis said. "They heard the baby crying, but they thought it was from his injuries. When they went over to care for him, the poor thing was covered head to toe."

Mr. Davis said techniques to control the fire ant are promising.

Two years ago, the Legislature gave Clemson University $1 million for fire ant research but required scientists to collaborate with 11 other states, including Georgia, North Carolina and Florida. With the money, they began fighting fire ants with flies - imported flies from South America.

The tiny insect, called a phorid, takes aim, then dive-bombs the ant with an egg, which quickly hatches into a maggot and moves into the ant's head. When the maggot is mature, it releases an enzyme that causes the ant's head to fall off.

Entomologists released the flies along the Grand Strand last year, but they seem to be losing the battle. The weather has worked against them.

Clemson University entomologist Clyde Gorsuch fears that the flies released at a Myrtle Beach golf course didn't survive last summer's hurricane, last winter's snow and now a drought.

Although the flies fend for themselves once they are established, scientists must closely watch their initial progress.

The flies harass the fire ants, which retreat to their mounds to avoid an attack. That means the ants won't forage as much, which also means they won't produce as quickly.

"They'll have a tougher time with the phorid fly around," Dr. Gorsuch said.

They also will be hard pressed to defend themselves against a microorganism called theolohania, which infects ant colonies and causes disease. The worker ants give the pathogen to the queen, she loses weight and lays fewer eggs.

"Using natural means to control fire ants restores balance to the environment," said Mac Horton, a Clemson entomologist. "Fire ants are having as harsh an impact on the environment as anything man can do."

Reach Chasiti Kirkland at (803) 279-6895.