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Fire Ant Facts

Color drawing of the red imported fire ant. By Joe McGown.
Color drawing of the red imported fire ant. By Joe McGown.
  • Fire ants first entered the United States about 1918, near Mobile, Alabama.
  • Fire ants reached Mississippi around 1930.
  • Fire ants now occur over much of the Southeast. [USDA fire ant quarantine map]
  • Northern migration of fire ants will likely be limited by cold—winter temperatures that freeze the soil deeply enough to affect overwintering colonies.
  • There are two species of fire ants in the state. Red imported fire ants are the most common, but some areas have black imported fire ants, or hybrids of these two species. These two species are similar in biology and behavior.
  • Fire ants are social insects that nest in the soil in large colonies that contain tens of thousands to more than 200,000 ants.
  • Fire ant mounds may be taller and more durable in certain soil types, such as heavy clay vs sand
  • During cold, wet weather fire ants tend to maintain their colonies high above ground—to keep brood out of water logged soil and to take advantage of solar heating.
  • During hot, dry weather fire ants tend to maintain their colonies below ground—to take advantage of cool, moist conditions.
  •  
    image of a fire ant mound surrounded by water during a heavy rain.
    Fire ant colonies can survive flooded conditions by “rafting,” and will establish a new mound wherever they happen to make landfall.
    (Photo courtesy of Chris Bennett)
  •  
    Fire ants building a bridge by joining legs to allow brood to be carried across short expanses of water, such as a water-filled tire rut.
    When forced to relocate, worker fire ants will use their bodies to build a bridge across narrow expanses of water to allow safe transportation of brood.
    (Photo courtesy of Dr. Victor Maddox)
  • Most of the ants in a fire ant colony are infertile, female workers.
  • Worker fire ants vary in size, but all are capable of stinging.
  • Usually there is only one queen per colony. The queen lays the eggs.
  • Fire ants have a complete life cycle. The eggs hatch into legless larvae, which develop into pupae and ultimately become adults.
  • Fire ants feed on a wide range of foods, including insects, honeydew, plant nectar, seeds, fruit and animal carcasses. They especially like foods high in fat.
  • Foraging workers exit the mound through underground tunnels that radiate away from the mound, exiting to the surface five to 25 feet away from the mound.
  • Adult fire ants are incapable of swallowing solid food. They have to carry it back to the mound.
  • Solid food is fed to the larger larvae, which chew and digest it and regurgitate it in liquid form.
  • Liquid food is passed from the larvae back to the workers and then shared with all ants in the colony.
  • Fire ants spread by swarming. Unmated, winged reproductive male and female ants exit the mound in mass, fly into the air and mate while airborne.
  • Newly mated fire ant queens fall back to the ground within a few hundred yards to a few miles of the mound from which they emerged, shed their wings and attempt to start new colonies.
  • At first the new queen is ‘on her own’. She lays a few eggs that eventually become small workers. These first workers then help care for their younger sisters and the colony begins to grow.
  • It takes several months for a colony to get large enough to build a mound large enough to be noticed in the average home lawn.
  • For every large mound in a lawn there are usually many younger colonies that are still too small to produce visible mounds.
  • Once a young fire ant colony is well established and has a few thousand workers, it can quickly develop into a mature colony containing tens of thousands of ants.
  • Small colonies develop into large colonies especially quickly if there are no bigger colonies nearby to compete with them.

Contact information for Dr. Blake Layton.

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News

Invasive fire ants crawl over a mound of soil. (File photo by MSU Extension/Kat Lawrence)
Filed Under: Fire Ants November 8, 2017

Just when we think we’ve conquered our tiny foes, it rains, and fresh fire ant mounds pop up in our yard.

Like many tasks around the house, fighting fire ants feels like a constant battle. My husband and I finally started seeing some progress when we followed recommendations from MSU Extension’s expert, Dr. Blake Layton. (Yeah, that’s a side benefit of my job, learning all kinds of practical information!)

Fire ant mounds are common along fence lines where they are protected from grass-cutting equipment and other traffic, such as this mound in an Oktibbeha County, Mississippi, pasture on May 11, 2015. (Photo by MSU Ag Communications/Kevin Hudson)
Filed Under: Forages, Insects-Forage Pests, Fire Ants May 19, 2015

STARKVILLE, Miss. -- Southern farmers may never win the battle against imported fire ants, but aggressive tactics can slow the pests’ invasion, reduce damage and prevent further spread across the United States.

Jane Parish is an Extension/research professor with the Mississippi State University Extension Service and the Mississippi Agricultural and Forestry Experiment Station. She said cattle and hay producers have learned to live with and work around the troublesome ants since the pests arrived in the state almost a century ago.

The biggest reason people have trouble controlling fire ants is that they only treat individual fire ant mounds. Individual mound treatments can be useful situationally, but need to be supplemented with broadcast treatments that will control all fire ants in all areas. (Photo by MSU Extension Service/Kat Lawrence)
Filed Under: Agriculture, Insects-Crop Pests, Insects-Forage Pests, Insects, Fire Ants, Insects-Pests May 15, 2015

STARKVILLE, Miss. -- People have many misconceptions on how to eliminate fire ant mounds and prevent them from coming back, and these erroneous beliefs hinder efforts to keep the harmful pest from spreading.

Many dogs spend time outside and often share their play areas with fire ants. When disturbed, the ants sting and deliver venom that can cause severe allergic reactions for some pets and children. (Photo by MSU Ag Communications/Susan Collins-Smith)
Filed Under: Fire Ants May 5, 2015

RAYMOND, Miss. -- Fire ants can be more than unwelcome guests in the home lawn; their stings can be dangerous for children and pets who share play areas with the pests.

Fire ant stings are characterized by sharp localized pain, swelling and intense itchiness that is just a short-lived nuisance for most. A raised red bump appears soon after the sting and soon turns into a sterile pustule that resembles a pimple. However, the ants’ venom can cause severe allergic reactions in some people and pets.

Most fire ants found in Mississippi are a hybrid between the red imported fire ant, pictured here, and the black imported fire ant. (Photo by Mississippi Entomological Museum/Joe A. MacGown)
Filed Under: Fire Ants April 24, 2015

STARKVILLE, Miss. -- Tell Mississippians that fire ants have completely invaded the state, and they’ll probably shrug and say they already know that. Tell them the pain actually comes from a sting rather than a bite, and they’ll say it still hurts. But tell them how to get rid of the nasty critters, and they’re all ears.

The Mississippi State University Extension Service is organizing efforts to help residents Bite Back against fire ants. The solution is a simple two-part attack, but success comes in the long-term follow-through.

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Fire Ant Control

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Entomology; extension insect identification; fire ants; termites; insect pests in the home, lawn and