Fire Ants Here to Stay

January 17, 2021 0 Comments

first_img“We know how to control fire ants and do it economically in urban settings,” Sparkssaid. “We haven’t found an affordable way to control them in open rural areas, such aspastures.” “We’re developing control programs,” she said. “We’re studying learning how to bestuse the control programs we already have. And we’re finding more environmentallyfriendly ways to control fire ants.” “If you get rid of them one year and don’t treat the next,” she said, “they’ll be the firstthings to come back. But they’ll become established in higher numbers, because theywon’t have larger mounds to compete with. Instead of 20 to 40 mounds, you’ll havehundreds.” But zapping fire ants is an every-year commitment. “If you treat them only one year,”she said, “you’ll be worse off than if you didn’t treat them at all.” “I don’t anticipate that phorid flies will be released in Georgia for fire ant control untilscientists at the Gainesville laboratory have studied them for many years,” Sparks said. “The fact that it’s a biological control agent indicates this fly won’t totally eliminatefire ants,” said Beverly Sparks, a University of Georgia entomologist. “We can get them out and keep them at levels that are acceptable in urban settings,”Sparks said. “But if you have 300-400 acres of pastures, it’s no longer cost-effective.” But don’t expect the tiny flies to decapitate Georgia fire ants soon. Scientists are working on other biological controls, too. For now, though, everythingthey know about killing fire ants won’t get rid of them. “All we can do now is controlthem,” Sparks said. “We tend to think of fire ants in terms of eradication,” Sparks said. “Phorid flies andother biological controls will stress colonies. They’ll suppress them. But they won’ttotally get rid of them.” Sparks’ research shows the best fire ant control is a simple two-step process.”Broadcasting a bait twice a year will reduce fire ant populations by 90 percent,” shesaid. “Then supplement the bait by treating problem mounds that survive with a contactpesticide.” A few phorid flies in Florida will have Georgians cheering them on in their naturalwork, chopping off fire ants’ heads.center_img With current products, effective fire ant control costs $20 to $25 per acre per year, shesaid. In home lawns, school yards and recreational fields, that’s reasonable. So scientists look for new ways to control them. Another UGA researcher, Ken Ross,is studying fire ant genetics. The technology to eliminate fire ants hasn’t arrived, she said. But for most people,controlling them is another matter. The U.S. Department of Agriculture released some Brazilian phorid flies July 9 tobegin field tests near its Gainesville, Fla., lab. But Sparks said biological controlagents won’t banish fire ants from U.S. soil. Sparks, a research and extension scientist in the UGA College of Agricultural andEnvironmental Sciences, focuses her own research on controlling fire ant populations. Specifically, Ross is trying to find why fire ants go from single-queen tomultiple-queen colonies. In the latter, worker ants sometimes destroy egg-layingqueens. If he can find the genetic trigger that causes that, he may be able to causesingle-queen mounds, in effect, to commit suicide. The prospect is fascinating, as is the ant-beheading phorid fly. The tiny fly lays its egginside a fire ant’s body. The egg hatches into a larva, which moves into the ant’s headand causes it to fall off. The fly completes its development inside the fallen head. Fire ants compete intensely with each other, she explained. Untreated, their populationwill level off at 20 to 40 mounds per acre. But don’t get too excited. Having to treat fire ants year after year is far too costly to be practical in farm-sizeareas.last_img read more