MONTVALE, N.J. (April 15, 2005) - The red imported fire ant (RIFA) will continue to make its way north and west into areas of the United States previously thought to be too cool for fire ant activity, says a joint study by the USDA's Agricultural Research Service Center and the University of Arkansas. According to the study, counties as far north as Prince George's County, Md. will experience "certain" fire ant activity that, in time, could pose a serious public health threat. Fire ant stings cause painful burning, itching and swelling, and in some cases, severe allergic reactions.

Results of the study predict that red imported fire ants will likely move 50-100 miles north into Oklahoma and Arkansas. They will also likely continue expanding into portions of Virginia, Maryland, and Delaware in the east and New Mexico, Arizona, California, Oregon, Nevada, and maybe even Washington and Utah in the west. A separate report published in the Journal of Allergy and Clinical Immunology (JACI) in 2000 indicates fire ants are traveling north and westward at a rate of about 120 miles per year. The report also indicates that fire ants are able to reproduce in areas where temperatures get as low as 10 degrees Fahrenheit.

"This migration is an indication that fire ants are more cold tolerant than scientists previously thought," explains Dr. Nate Royalty, PhD., entomologist with Bayer Environmental Science. "We expect fire ant expansion to continue northward and westward as fire ants find more areas to infest."

Natural fire ant expansion is exacerbated by movement of infested soil. Fire ants can also "hitchhike" on birds or mass together to form a floating ball to ride out floods, which can take them as many as 10 miles away from their original colony. Another method is through breeding, which happens 300 to 800 feet in the air. After mating, the female floats back down to the ground and attempts to establish a new colony on a suitable moist site. Although usually just a few feet from her original colony, the female will sometimes establish her new home miles from the original location.

Children, the elderly and pets are the most at risk for fire ant stings. More children are stung each year by fire ants than by all other insects combined.

Traditional methods of treatment consist of treating mounds individually through the use of a drench, injections, dusts, baits or fumigants. These methods provide a quick kill of active mounds, but do little to keep fire ants out of turf for a sustained period. Since 2001, many lawn care and pest control professionals recommend a new way to combat the population - fire ant prevention. With preventative, granular insecticides like TopChoice^™ from Bayer Environmental Science, the treatment is spread over lawns and beds like a fertilizer, creating an exclusion zone where no fire ant can survive.

"Fire ant prevention through the use of technologies like TopChoice may be the best options for folks with little experience dealing with these pests," says Royalty. "Homeowners should talk with their local lawn care or pest control professional, or visit www.nofireants.com for more information."