When people think of “dangerous invasive pests,” fire ants might not necessarily come to mind.
While many people view fire ants as a ubiquitous part of life, the pests have actually only been in North Carolina since the 1950’s, after being imported to the United States in the early 20th century. Since first being detected in Brunswick County in 1957, the ants, known formally as Red Imported Fire Ants, have spread throughout the state and are now found in 77 counties.
The ants are nearly impossible to eradicate said Whitney Swink, State Regulatory Entomologist. This is due to a combination of factors; the ants breed remarkably fast and can out-compete other ant species around them, and they have proven adaptable to all kinds of changes in their environment.
“They are really good at adapting to disturbed areas. Construction, for example, new neighborhoods coming in with a bunch of equipment. That is, for lack of a better word, candy for fire ants,” Swink said. “Disturbed areas make is much easier for them to get into the ground, likely because the soil is getting loosened up which eliminates some of the work they would have to do to burrow underground.”
The ants can also feed on all kinds of things, from plant roots to small animals and even parts of electrical and farm equipment. Add all of that to the ants’ dedication to protecting their queen – the insects will go as far as creating a living raft from their bodies to keep their queens out of the water during flooding – and you have a recipe for an extremely difficult to dislodge pest.
The ants are most prevalent in eastern and central North Carolina, Swink said, but could begin to appear in the colder areas to the West.
“There was some older research which showed that the ants absolutely could not survive in the colder climates at higher elevations, so most of western North Carolina would hypothetically be spared from fire ants,” she said. “Current research, however, is showing that they are actually adapting and getting better at burrowing deeper underground, and we are beginning to find them in western North Carolina.”
Fire ants both bite and sting, but while painful and uncomfortable, a single bit or sting is unlikely to pose serious danger. However, in cases where the victim is allergic or has been bitten or stung several times, the ants can be dangerous, especially to young children.
“Most people if bitten or stung will have a pretty minor allergic reaction, but some people can have severe reactions, especially if you somehow end up with a lot of bites,” Swink said. “For instance if you step on a mound that you didn’t know was there. In general they are a cause for concern. They aren’t something you should be terrified of, but certainly exercise caution around them.”
To help slow down the ants, the North Carolina Department of Agriculture and Consumer Services maintains a fire ant quarantine in counties with established fire ant populations. The quarantine mandates the inspection of a list of items when moving through or into non-quarantine counties, including sod, soil, hay and straw, nursery stock, logs or pulpwood with soil and soil-moving equipment.
People who find fire ants on their property should contact their local agricultural extension for information on how to treat them. County extension agents are the people who will be most up to date on the right pesticides and chemicals to use in treating a fire ant infestation, Swink said.
Swink also recommended that people be aware of if they live within the fire ant quarantine, and report sightings if they are not.
“If people live within the quarantine, we already know the fire ants are there,” she said. “If you have fire ants popping up in western North Carolina, say Surry County for example, and you start seeing fire ants, I would be curious about that. That would be a sign that they are spreading beyond our quarantine, and we as a regulatory agency would want to take a closer look and keep an eye on that population.”
A map of the quarantine area is available online at https://www.ncagr.gov/plantindustry/Plant/entomology/documents/ncifaquarantine.pdf. To report fire ants outside of the quarantine area, contact Swink at (919) 707-3742.