A
helicopter takes off at Camp Misty Meadows on its way to apply fire ant
bait to 100 acres there. (Photo courtesy of Bart Drees, Texas Cooperative
Extension)
(College Station)—Urban residents have bags of ant bait and hand-held spreaders. Landowners with large tracts of land have crop dusters. But what about the people with moderate-sized properties who want to enjoy their land without the bother or health hazards of red imported fire ants?
Recent Texas Cooperative Extension demonstrations may provide part of the answer, said Bart Drees, Extension entomologist.
Recently compiled results from the demonstrations showed excellent control of fire ants was achieved by applying a "hopper blend"—a combination of two granular baits—from a helicopter, he said.
On June 16, the helicopter treatment was applied to 100 acres at Camp Misty Meadows near Conroe, a camp owned by the Girl Scouts of San Jacinto Council.
Before treatment, each of the five monitored areas averaged 120 ant mounds per acre on the day of treatment, said Paul Nester, Extension agent for integrated pest management in Harris County. Four months later, mound numbers had been reduced by 96 percent to four mounds per acre, he said.
A reduction of more than 82.2 percent occurred after the second demonstration, which took place on 130 acres at the Britt Rice exotic game ranch near College Station, Drees said. Fire ant mound numbers were reduced from an average of 199 mounds per acre on June 17—the day of treatment—to 35 mounds per acre on Dec. 1.
Areas around houses and ponds were treated with either hand-held applicators or with a ground rig that Extension faculty also helped develop, Drees said.
"We've got the data now," Drees said. "We got great control. The goal of our program is to bring fire ant control to larger land tracts. The larger the area you manage ants on, the longer the control lasts."
Extension demonstrations with crop duster-applied bait have shown an 80 percent to 90 percent reduction of fire ant mounds. However, helicopters are more maneuverable than crop dusters and can fly over mixed urban/agricultural areas or urban areas, he said.
"With a helicopter, you can fly over near-urban neighborhoods with agricultural areas in between and provide community-wide application on a larger scale, provided you have approval and support of all the residents," Drees said.
The helicopter distribution method's "surgical" precision allows it to avoid farm ponds where bait is not allowed to fall, Drees said. Helicopters also reduce "drift" into areas where individuals or communities have opted out of treatment.
The red imported fire ant was accidentally introduced into the U.S. in the 1930s. It now infests more than 260 million acres of land in nine southeastern states.
In Texas, the average number of fire ant mounds is 67 per acre, and with multiple-queen colonies, many neighborhoods and areas have more than 300, Drees said.
"We've got an ant problem," he said.
Extension promotes the Texas Two-Step program—a bait treatment followed by nuisance mound treatment—for urban yards as the least-toxic, most cost-effective approach for heavily infested properties and neighborhoods. Other approaches are also available and can be used where justified.
Fire ant control options available to ranchers and large-tract landowners include aerially applying baits using a crop duster or helicopter at a cost of about $17 per acre that includes the cost of the insecticide bait product, he said.
"To justify this expense in a commercial operation, operators need to potentially be losing $17 per acre," Drees said, adding that the cost is reasonable if high-value animals or costly equipment are in danger of being destroyed by the ants. In other cases, potential human medical problems such as allergic reactions to ants justify the expense.
If landowners cannot justify treating the entire property, Extension recommends a targeted plan, such as using Two-Step or other chemically based method around homes, barns and other areas where people congregate. In pastures, non-chemical or cultural options such as periodic dragging of fields, immediate removal of hay bales for fields, and scheduling animal fertility programs to avoid summertime calving, can help avoid ant problems without an insecticide.
Extension and Texas Agricultural Experiment Station researchers are cooperating with the University of Texas and the U.S. Department of Agriculture in phorid fly releases as part of a biological control effort. The tiny flies parasitize fire ants and suppress ant foraging during the daytime. Other research is being conducted as well.
"We are trying to provide as many alternatives (for ant control) as possible," he said. "The helicopters are a small piece of a bigger picture."