Why am I losing the battle against fire ants in my yard? ASK THE HORT AGENT
Question Why am I losing the battle against fire ants in my yard?
Answer As Elizabeth Barrett Browning said, “Let me count the ways.” There are many reasons why your control tactics may not be working. First, keep in mind that fire ants have no intention of going peacefully. They are survivors and colonizers. All efforts to control them must be calculated and wholeheartedly executed.
The two primary pesticide approaches are mound treatments and baits. Mound treatments are pesticides which are applied directly to the fire ant mound. The two general types of mound treatments are powders (dusts) and drenches. The success of either type can be jeopardized if the fire ant mound is disturbed prior to adding the pesticide.
Drenches require water. Improper mixing of the pesticide, resulting in the wrong rate, can be a factor in treatment success. Varying amounts of water are used with drench treatments depending on the brand. If the pesticide label says to use 3 gallons of water, then 1 gallon may not be enough, and 5 gallons may be too much. Simply read and follow the label instructions.
Both types of mound treatments kill hundreds of fire ants even if they are applied incorrectly. However, there is only one fire ant per mound that really matters – the Queen. If you do not kill the queen, then a new mound will pop up nearby in 1 to 3 days. It is imperative that this new mound is treated as soon as it is identified. A fire ant queen is easier to kill in a small new mound than in a large old mound. Therefore, schedule a second or third scouting trip around your property within 3 days of any mound treatment.
Wire flags can be used to help with fire ant mound monitoring. First, place a wire flag beside every fire ant mound. Then treat the mounds. Being able to spot the flags will help you monitor treated mounds and distinguish them from new mounds. The flags can be removed and reused after the mounds have been declared inactive.
The second major pesticide approach is the use of baits. These products work best in situations where every fire ant mound can not be treated individually (ex. large properties, ditch banks, fence lines, etc…). The downside is time. Baits typically require from 2 to 8 weeks to work, depending on the brand used. They do not work overnight. This time lag is often interpreted as “not working.” In reality, it’s just slow. Baits also have to be fresh. Old bait may become rancid and not attractive to the fire ants.
Baits and powdered mound treatments need to be applied when the ground is dry and will continue to be dry for several hours. Dew does count as moisture, especially this time of year when dews are heavy.
For more info on fire ant control visit this website http://edis.ifas.ufl.edu/LH059 If you don’t have internet access, then call the Extension Office at 893-7533 or email me at gpierce@harnett.org
Fire ant colonization is greatest during the fall and spring. The use of mound treatments and a bait during the fall or spring is called the Texas two-step method. Getting rid of the fire ants (even temporarily) will be reason to two-step around the yard.
Gary L. Pierce
Horticulture Extension Agent
Harnett County | 
