San Antonio Express News
Sunday, September 12, 2004
By Nathan Riggs
In the seven years that Fire Ant Awareness Week has been a part of each Texas September, many changes have occurred in the way fire ant treatments are chosen, applied and evaluated. This year, Fire Ant Awareness Week in Texas runs September 12 through 18, 2004. Let’s examine some of the changes that have occurred since the inception of this annual event in 1998.
First of all, the way fire ant treatments are approached has changed dramatically. The once popular method of treating entire lawns with insecticides that kill everything (and sometimes not do much to the fire ants) have been replaced with more sensible, target-specific means. Gone are diazinon and dursban (chlorpyrifos) and in all products containing fipronil, permethrin, or bifenthrin. Permethrin and bifenthrin are newer synthetic pyrethroid insecticides providing better safety around mammals. Fipronil is an ingredient found in Merial® Frontline™ flea products and Gardentech® Over-N-Out™. While bifenthrin and permethrin are considered broad-spectrum insecticides, fipronil is different. It sticks to the soil and stays put, but only kills insects that dig a lot. Fire ants and mole crickets are the primary targets for Over-N-Out®. Over-N-Out® is applied once per year, kills all fire ants within three weeks after treatment, and continues to do so for 12 to 14 months. For all practical purposes, treating your entire lawn with a broad-spectrum insecticide for fire ants should only be done as a last-ditch effort. There are more efficient, less impacting ways as we’ll see next.
If you have less than five fire ant mounds in your lawn, treat only those mounds. This will allow native ants and other insects to survive and flourish after the fire ants have died. Mound treatments can be as simple as hot water or as complex as you wish them to be. The only rules that must be followed go something like this: 1) Follow all granular treatments (not baits) with one gallon of water. 2) Treat early in the morning or late in the evening during hot weather, 3) Moisten “flat” fire ant mounds with water prior to treatment to bring the ants to the surface, and 4) DO NOT disturb fire ant mounds prior to treatment because the ants will try to vacate the nest and escape the treatment.
Many mound treatments are on the shelves for fire ants. Whether conventional or naturally based, be sure to follow the label directions for success.
For those of you with more than fire mounds in your yard, there is only one way to effectively deal with fire ants in a cost-effective, low toxicity and time-saving manner: The Texas Two Step Method. The Two Step Method is easy and conforms to many folks’ wishes for a low cost, low toxicity way to terrorize fire ants. Here’s how it works. Step One involves choosing a fire ant bait product to spread over the lawn. Today’s bait choices include Amdro®, Ortho® Fire Ant Killer™ Bait Granules, Green Light® Fire Ant Control with Conserve®, Award® and Extinguish™. The first three baits on the list work within 14 days of application and the last two kick in around six weeks after treatment. Spread the baits at the rate of one pound per acre with a hand-held spreader. There should be no rainfall or watering within 12 hours of bait application for best results.
For those who prefer natural ingredients, the Ortho and Green Light baits contain spinosad, a chemical extracted from soil organisms. The Green Light and Extinguish baits are also approved for vegetable gardens.
The second step of the Two Step requires treatment of “nuisance” fire ant mounds near high traffic or sensitive areas with a fast-acting mound treatment. All mounds are not treated in the second step-just the “nuisance” mounds described above.
The Two Step requires a cost of ~$5 per year investment in chemicals, and one treatment lasts six months or longer. The best time to treat fire ants for maximum effect is in the fall of the year. Fall treatments reduce fire ants 90% by springtime.
The best place to use the Two Step Method is in a concerted neighborhood effort targeted at fire ants. San Antonio neighborhoods have reduced pesticides and treatment costs for fire ants by as much as 90% by banding together for a “Fire Ant Day.” Call the Extension office at (210) 467-6575 for more information on fire ants and “Fire Ant Days” or visit the Texas Fire Ant Program website at http://fireant.tamu.edu.
This article was written by Nathan Riggs, Extension Agent-IPM, with Texas Cooperative Extension’s Texas Fire Ant Research and Management Program.