Habitat

Thief ants are native to the United States, especially the Eastern states. They prefer to live in fields and meadows and can also live in grassy areas such as golf courses and lawns. They build nests in the soil, sometimes underneath rocks and logs, other times out in the open. Typically they will build their nest close to the nests of other species.

In the home, thief ants can be found inside wall voids, baseboards, soil beneath cracked foundations, and other dark areas. Often, the presence of other ant species is what brings the thief ants inside. However, they may also be feeding on your food. Thief ants love greasy, protein-rich foods and sweets, and so they are often found foraging in kitchens where food is kept.

Behavior

Thief ants will feed on almost anything organic. That includes other insects, the honeydew produced by aphids, seeds, fruits, and dead animals. Inside, they will forage in trails as they hunt for food. Often, they use wires and pipes to travel through wall voids in the house and get from room to room. They require lots of protein, so they will happily feed on meat, oils, nuts, and dairy products. However, they will also eat sweet foods.

Often, thief ants come inside when hot weather causes many of their outdoor food sources to diminish. They will also come inside on the hunt for the ants to steal from or if there is a reliable food source inside your house.

Reproduction

Thief ants are polygynous, meaning there is often more than one queen to a nest. Colonies can be anywhere from a few hundred ants to several thousand.

Thief ants reproduce by means of a nuptial flight. At certain times of the year, the queens will begin to lay eggs that can develop into winged reproductive ants that may be either male or female. Between June and October, these winged ants will emerge and start to fly. The ants mate in the air, with the males dying shortly afterward. The mated queens usually fly off to establish a new colony. However, they will sometimes return to their original nest and begin to produce eggs there, helping the colony grow even quicker.

It can take around 50 days for an egg to grow into an adult worker ant. During this time, the eggs and growing larva are tended to by adult ants. When an ant larva is ready to become an adult, it pupates and changes form from a wormlike larva to a six-legged adult.

Danger?

Due to their small size, thief ants are incapable of stinging or biting humans. However, due to their habit of foraging widely and consuming other insects, it is possible that they could transmit bacteria to human food. Pharaoh ants are known to do this, and thief ants have similar habits to Pharaoh ants. However, a link between thief ants and food contamination has yet to be proven.

Signs of an Thief Ant Infestation

Generally, the first sign of a thief ant invasion is the ants themselves. Because the fans forage in well-established trails, they can be quite easy to spot, despite their small size.

If there is a nest inside, winged reproductive ants may emerge during the summer. Pay special attention if you see ants going into a hole in the wall underneath the baseboard. This may indicate the presence of a nest.

Controlling Thief Ants

So, how to get rid of thief ants? The best way to control thief ants is to target the nest directly. To find the nest, it may be necessary to follow foraging ants. If you see ants carrying food particles, you can be sure they are returning to the colony and may help you determine where the nest is. Also look for areas of high ant activity, especially going into and out of the structure of your home.

Once the nest is located, you can treat it with a residual pesticide. Foams and dusts are especially effective in wall voids, because they will spread easily through the colony. However, make sure not to use them together, because wet foam will decrease the efficacy of a dry dust.

Recommended Product: Ortho Home Defence Insect Killer

Outdoor Control

Where thief ants are nesting outdoors, you can destroy the nest by the direct application of a liquid pesticide. Note that you will also need a sprayer to adequately saturate the soil. Pesticides such as Cy-Kick and Demand are useful for this task.

Spray Outdoor Perimeter

Spraying the perimeter of your home with a residual pesticide will help prevent thief ants from coming inside. Any ants that come into contact with the area that has been sprayed will be killed by the pesticide, even after it has dried. Sprays like Demon or Suspend provide good protection. Make sure to spray three feet up the wall from the foundation and three to six feet out from the house to create a good barrier.

How to Get Rid of Thief Ants – Best Products

Inside the House:

Inside the house, the best way to treat thief ants is to target the nest directly. If the ants are nesting in a wall void or crevice somewhere, the use of an expanding pesticide foam or dust can be very effective in destroying the colony. These products can stay active for months, making sure that the ants are completely eradicated.

Recommended Bait:

Delta Dust

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Ant Bait Stations:

If you can’t find the nest, ant baits can help. These products combine a stomach poison with an attractive bait that the ants will want to eat and bring back to the nest, feeding it to the queen and her brood and killing the ants that way.

However, thief ants don’t respond as well as some other species to baits. Often, they don’t feed on bait long enough to provide effective control. Remember to tailor any baiting program to the ant’s feeding preferences. Thief ants like sweets, but they also feed on protein, so try to use a bait that uses a protein-based attractant.

The best strategy is to use a combination of bait and contact pesticide to target both the nest and the foraging ants. For the most effective products, check out our ant control kits here.

Recommended Ant Bait Station:

Advance Dual Choice Ant Bait Stations

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Best Products for Outside the House:

A pesticide spray with a long-lasting residual is the best way for how to get rid of thief ants outside the house. You can use these sprays directly on a nest to destroy it and spray them around your home’s perimeter to create a repellent barrier the ants won’t want to cross.

Recommended Exterior Ant Spray:

Suspend

Buy Now

Preventing Infestations

• Create a perimeter around your home by spraying residual insecticide to keep ants away.
• Seal up any cracks and crevices that ants could use to get inside with weatherproof silicone caulk. Pay special attention to cracks in the foundation and holes in the wall where water pipes enter. Also pay attention to gas meters and air-conditioning units.
• Store food in ant proof containers such as glass or Tupperware that forms a seal so ants can’t get inside.
• Clean up any food spills as soon as they happen to avoid attracting ants. Pay special attention to grease or fat spills, as well as spills of sweet substances such as soda or ice cream.

Resources

https://animaldiversity.org/accounts/Solenopsis_molesta/
http://ipm.ucanr.edu/TOOLS/ANTKEY/thfbait.html
https://en.wikipedia.org/wiki/Solenopsis_molesta

Habitat

Native to the US, these ants are often a tree-dwelling species. Acrobat ants are not capable of boring into sound wood, but they will use holes made by other insects such as caterpillars and termites to get inside trees.

Inside the house, Acrobat ants can often be found foraging for food. Although they are omnivorous and will eat a wide range of food, they show a preference for sweets and high-protein foods such as meat and nuts.

Sometimes, Acrobat ants will establish a nest inside a structure. This usually happens in wood that has become water damaged or rotten, since it makes it easier for the ants to chew through. They will also nest in Styrofoam insulation inside wall voids. Additionally, they may recolonize dead nests of wood-destroying insects such as termites and carpenter ants.

Behavior

Acrobat ants are aggressive and predatory, and will actively hunt down other insects such as caterpillars, termites, and wasps. They also feed on the honeydew produced by aphids. Like many ants, they will protect aphids from other predators to harvest the honeydew. Acrobat ants will also sometimes protect the aphids by building shelters from chewed-up tree bark that they turn into a substance like cardboard.

Acrobat ants use their venom to immobilize their prey. They will team up to carry insects back to the nest, where they feed them to their larvae. They also use venom in self-defense, and will release it when they feel threatened. This is what generates the foul-smelling odor these ants produce.

Reproduction

Acrobat ant species are monogynous, meaning a nest only has one queen. When the nest becomes mature, the queen will start producing winged ants that are capable of reproduction. These ants can be either male or female. During the summer, these ants will leave the nest and swarm, mating in mid-air. The males die shortly afterward, and the fertilized females go on to start new nests of their own.

In the wild, new queens enter trees through holes made by other insects. The queen will lay eggs to produce workers that she will feed herself from the muscles of her discarded wings. When these small workers are old enough, they will begin foraging and help the queen care for the next generation of eggs. As the nest matures, the queen and her brood will move further down the tree, seeking out abandoned termite nests or other holes she can use to get underneath the tree.

Sometimes, a new queen will instead build a nest in damp wood inside a building. Acrobat ants can only nest in wood that has already been damaged by water or fungus. However, they can also use insulation to build a colony.

Danger?

Acrobat ants can’t hurt people directly. However, they can damage insulation by building nests inside it. Sometimes, they will also strip insulation from electrical wires, which can cause short-circuits. 

Signs of an Acrobat Ant Infestation

You may see these ants inside your home, following established trails toward a source of food or water. Often, ants that are nesting outside will make their way inside in the hunt for food. However, if you have water damaged wood in your home, the ants may also be nesting inside. If you see ants regularly going in and of a hole in the wall or a gap under the baseboard, there may be a nest inside.

Another sign that you may have a nest of Acrobat ants is the debris the ants eject from the nest. Known as frass, this material is made up of tiny particles of the substance the ants are nesting in, whether rotten wood or Styrofoam insulation. Piles of frass may be seen underneath holes where ants are nesting, and are a clear sign of an established Acrobat ant colony.

Controlling Acrobat Ants

If Acrobat ants have established a nest inside your home, the best method to get rid of them is to directly destroy the nest. Naturally, this means you’ll need to find the nest. Concentrate on areas with a lot of moisture. Think of anywhere you’ve had a water leak in the past. You can use a moisture meter to help you identify these areas. Also inspect former termite or Carpenter ant nests.

If you find an Acrobat ant nest inside your home, you can treat it directly with a residual pesticide. Foams and aerosols are useful for this task, because they will fill the void of the nest completely. You could also use a dust, since dusts stay active in wall voids for a very long time, preventing reinfestation.

Recommended product: Termidor Foam

If the ants are nesting outside the home, a light application of non-repellent pesticide on foraging trails can help to keep the population down. However, it is unlikely to destroy the colony completely.

Poison baits can also be effective against Acrobat ants. However, bait acceptance can be poor with some species, since these ants like to prey on other insects.

Outdoor Control

Treat the nest

Check logs, stumps, firewood, and tree cavities for ant nests. Trails of foraging ants can also lead you to the colony. If a nest is discovered, treat it directly with a liquid pesticide such as Demand or a foam pesticide like Ortho Home Defense. Try to inject the pesticide directly into the wood or soil where the ants are nesting. Foams and aerosols are useful for this task.

Perimeter spray

To keep ants out of your home, perform a perimeter spray with a residual insecticide such as Suspend around the exterior of the building. Spray three feet up from the ground and three to six feet out from the wall to create a barrier that will kill any ants to try to cross it.

Best Products to Get Rid of Acrobat Ants

Inside the House:

Acrobat ants inside the house are often foragers who live outside. Therefore, the best strategy is often to focus on killing the ants and keeping them from coming inside.

Spraying foraging ant trails with a non-repellant pesticide allows the ants to bring the pesticide back into the colony when they return from foraging.

Recommended Bait Types:

Recommended Non-Repellant Insecticide:

Taurus SC

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Ant bait can also be an effective way to treat Acrobat ants when you can’t treat the nest directly. Baits allow the foraging ants to take a slow-acting poison back to the nest and feed it to the queen and the brood. A successful baiting program requires patience, but it can be a great way to destroy the colony for good.

Recommended Bait:

Advion Ant Gel

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Ant Bait Stations:

Ant bait stations provide a quick and easy way to deliver bait without the mess of gels and liquids. Bait stations keep the bait contained so that it doesn’t spill. This also helps to keep the bait safe from pets and young children.

For more information on ant bait stations click here to see our full Ant Traps and Bait Stations Review.

Recommended Ant Bait Station:

Terro Liquid Ant Bait

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Best Products for Outside the House:

Outdoors, pesticides with residual killing power are the best way to keep acrobat ants outside your house. By spraying around the building, you can create a barrier that will both repel the ants and kill any that try to cross it.

The same sprays also work as contact killers. Therefore, if you find an Acrobat nest outside, you can treat it with the same spray.

Recommended Residual Ant Spray:

Suspend

Buy Now

Preventing Infestations

• Remove tree stumps, rotten fenceposts, firewood piles, and other sources of water-damaged wood from your property.
• Use weatherproof silicone caulk to seal up cracks and crevices where ants may come inside. Pay special attention to gaps in foundations and where pipes and wires enter the house.
• Look for signs of excessive moisture such as peeling paint along soffits and around window frames.
• Be on the lookout for fratss from ants nesting inside the structure of the house.
• Keep tree branches and shrubs trimmed back so that they don’t touch the house and provide a way for ants to get to the building.
• Store food in sealed containers such as Tupperware or glass.
• Clean up food spills immediately.
• Put pet food away at night.

Resources

• https://www.pestworld.org/pest-guide/ants/acrobat-ants/
• https://www.antwiki.org/wiki/Crematogaster
• http://entnemdept.ufl.edu/creatures/urban/ants/acrobat_ant.htm

Habitat

Little Black ants can live both indoors and outdoors and prefer dark and inaccessible places to make their nests. They are often seen foraging for food both inside and outside buildings. The ants will follow pheromone trails to guide them toward food sources, and these trails are often the first indication of the presence of little black ants.

Inside the house, nests are located in woodwork, wall voids, decaying wood, and masonry. Outside, the ants can often be found in soil and rotten wood. They often nest under stones and rocks or piles of bricks or lumber. Rotting fence posts and logs also make good nest sites for Little Black ants.

Behavior

Little Black ants are opportunistic scavengers that will feed on a wide range of food. Grease, oil, meat, fruit, vegetables, and sweets are all on the menu for these tiny ants. They will also feed on other insects, and like many ants, have a particular liking for the honeydew secreted by aphids. Little Black ants will guard aphid colonies to protect this important food source. Often, little black ants come indoors after rain because the honeydew washes off the plants outside, making it necessary for them to seek out new food sources.

Like most ant species, Little Black ants bring food back to the colony and feed it to the larvae and queen. They practice a distinct division of labor to keep the colony functioning. Foraging adults only make up a small percentage of the total population of the colony. The adult ants are dependent on the larvae, just as the larvae are dependent on the adults. For that reason, the best way to get rid of these ants is to directly target the nest.

Reproduction

Little black ants are polygynous, meaning a nest has more than one queen. Ordinarily, the queens are the only members of the colony capable of reproduction. However, in summer, a mature colony will begin producing winged reproductive ants that can be either male or female. These winged reproductives take part in a nuptial flight and mate in the air. After mating, the males soon die, and the mated females fly off to found nests of their own.

Once a queen establishes a nest, she will begin producing eggs. Typical Black Ant colonies number a few thousand individuals. Similar to Fire ants, Little Black Ants go through a complete metamorphosis in their lifecycle, from egg to larva to adult. It takes around one month for an egg to grow to adulthood, at which time it will either begin foraging for food to support the colony or else help look after the larvae and maintain the nest.

Danger?

Little Black ants are not a significant vector of disease. And while they have stingers, they are only used on prey or in battles with other ants. Little Black ants are too small to sting humans or pets and are incapable of causing structural damage, but they will sometimes excavate already rotten wood to build a nest. Mostly, they are just a nuisance.

Signs of an Little Black Ants Infestation

Because of their small size and secretive habits, these ants can be hard to spot at first. Usually, the only way to know you have a problem is to spot the ants themselves. You may find them moving in trails through your kitchen or bathroom. You may even see them entering a crack in a wall or a gap in a baseboard as they come and go from the nest.

Controlling Little Black Ants

The quickest and most effective way to get rid of Little Black ants is to destroy the nest. Targeting the nest directly with a residual pesticide will destroy the queens and the brood, breaking the lifecycle of the colony. The residual pesticide will also keep killing ants that come into contact with it even after it has dried. Because little black ants often nest in hidden and inaccessible areas, residual pesticides can be safely used to control them.

Recommended Product: Suspend Polyzone Insecticide

However, because of their secretive nature, it is often impossible to find an indoor nest of Little Black ants. In these situations, the best tactic is usually to use a poison bait that the ants will bring back to the colony themselves. Although baiting takes longer than treating the nest directly, it is a safe and effective way to deal with an ant colony when you can’t locate the nest.

Outdoor Control

Outdoors, you can use pesticides such as Suspend or Demon to soak the soil or wood where little black ants are nesting to destroy the colony. These pesticides have a powerful residual effect and will continue to kill ants even after they are dry. Note that you will need a sprayer in order to apply these products.

Spray Outdoor Perimeter

You can help to protect your home from little black ant infestation by using residual pesticide to spray around the outside of the building. Spray all the way around the house, creating a band of pesticide around three feet high on the wall and 3 to 6 feet out into the surrounding soil. Pay special attention to areas where ants are likely to get inside, such as cracks in the foundation or places where pipes enter the house.

Best Products to Get Rid of Little Black Ants

Inside the House:

Indoors, if you can find where the ants are nesting, you can treat the colony directly to achieve the quickest control possible. Foaming pesticides can be great for wall voids, since you can inject the pesticide and let it expand to fill the void. Dusts and powders can also be very effective inside wall voids, since they will stay active for a very long time. In this way, they not only killed the nest but also prevent any new nests from being established.

Recommended Bait Types:

Recommended Foam:

Ortho Home Defense Insect Killer

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Recommended Dust:

Terro T600 Ant Dust

Buy Now

Ant Bait Stations:

Ant bait stations are a great choice to use when you’re not sure where the nest is located. By combining a stomach poison with attractant bait, bait stations cause the ants to bring the poison back to the colony themselves. While this can take some time, it ensures that the poison spreads through the colony and kills all the ants.

Also, bait stations keep things neat by storing the ant bait inside plastic containers. This helps reduce spills and also ensures that pets or young children can’t access the bait.

For more information on ant bait stations click here to see our full Ant Traps and Bait Stations Review.

Recommended Ant Bait Station:

Maxforce FC Ant Bait Stations

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Best Products for Outside the House:

Outdoors, direct pesticide treatment is the best way to kill a colony of Little Black ants. Make sure to soak the soil or wood where the ants are living using a sprayer. Choose a residual pesticide that will continue to kill ants that attempt to recolonize the area.

You can also use these products to create a barrier around your house. Even after the pesticide dries, the barrier will repel any ants trying to enter and kill any that cross it.

Recommended Residual Pesticides:

Suspend Polyzone Insecticide

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Demand CS

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Preventing Little Black Ant Infestations

• Use weatherproof silicone caulk to seal up gaps and cracks in the exterior of your house and prevent ants from getting inside. Look for cracks in the foundation, gaps where water and gas pipes enter, dryer vents, and air conditioning conduits.
• Cut back branches that come into contact with the house. Ants can use these as a highway to get inside.
• Remove any areas of rotten or water damaged wood. Little Black ants like to build nests in these areas.
• Inside, store all food in sealed containers such as Tupperware or glass. This will ensure ants can’t reach your food.
• Perform a regular exterior spray of your house to keep ants and other bugs from Check inside your home for water leaks and areas of water damage where ants could nest.

Resources

• https://web.archive.org/web/20120806014546/http://urbanentomology.tamu.edu/ants/little_black.html
• https://en.wikipedia.org/wiki/Little_black_ant

Habitat

Ghost ants are highly adaptable in their nesting habits. Colonies are moderate to large in sizes with several reproducing female ants. These ants commonly occupy local areas that are small or unstable to support entire large colonies outdoors, such as:

• Tufts of dead, moist grass
• Plant stems
• Cavities beneath detritus in open
• Potted plants
• Under loose bark
• Bases of palm fronds

Indoors, they mostly stay in places like:

• Wall voids or gaps
• Cabinetry
• Baseboards
• Potted indoor plants
• Foundation cracks
• Spaces between books

In the United States, the ghost ant is commonly found is Florida and Hawaii. Its range is expanding. They have now reached some parts of Texas.

Behavior

Ghost ants are highly adaptable in their habits when nesting. They thrive indoors and outdoors. Their colonies have multiple reproducing female ants and their colonies can range from medium to large sizes. They are opportunistic nesters, they nest in an area for a few days or weeks and then they start looking another place.

Multiple female reproductive ants spread out in different sub colonies. They are very attracted to the indoors and they build their colonies by means of budding. Budding is when one or more female ants, accompanied by several workers and some brood (larva and pupae) leave an established nest or colony to find a new nesting site. Fighting between members of different colonies or nests is not common.

The worker ants have a mannerism of running erratically when disturbed. They like honeydew and they tend to honeydew-excreting insects. They feed on dead and live insects, including some species of ants. Movement of worker ants are slow and deliberate. They will get into structures from their nests near foundations or from plants near the building.

Reproduction

Ghost ants have a polygene and unicolonial colonies. Unicolonial colonies have separate but cooperatively interacting nests. Their nests can build up large numbers. Individual nests may have 100 to 10000 ants and will have multiple reproductive female ants. New colonies are formed by the migration of one or more female reproductive ants accompanied by several workers. They have not been reported to have nuptial fights like the other ant species. No fighting between nest members or colony members were reported or observed based on studies, at least those from within the same area.

Ghost ants have four larval stages from the hatching of eggs to the adult stage. The worker ants development from egg to adult lasts 16 to 52 days. Its embryonic stage is longer than the larval, prepupal or pupal stages. One female queen can produce 5.3 eggs per day and is relatively slow compared to other ant species. None the less, because of the multiple reproductive female ants in a colony, the colonies are able to grow substantially.

Danger?

Ghost ants post a social impact through their association with food supplies.
Based from different studies, these ants have been reported as a significant urban pest capable of infesting residential kitchens, commercial food chains etc, in large numbers. They can get into buildings and other structures though small openings, cracks and crevices. It has been established that this is one of the most common ant species infesting houses. There are no reports about structural damages or wiring, but it’s been considered as the most important house-infesting pests. Complaints were mostly due to it being a general nuisance or infesting food.

The health impacts of ghost ants vary. Some reports are about people suffering from mild irritation of the skin following contact with the ant. They may also have some contribution to disease transmission. They are prevalent in hospitals in South America and are capable in transporting pathogenic microbes such as Enterobacter cloacae and Staphylococcus.

Signs of a Ghost Ant Infestation

When you put a teaspoon of sugar, you can judge the level of contamination by how many worker ants are floating on the surface of your drink!
These ants have a peculiar color and marking and is small in size. Look for them in kitchens and bathrooms, sinks, counters and floors. When crushed, they emit a smell of a rotten coconut, so if you notice this smell after cleaning up, you might want to do a thorough check and look out for these ants.

Controlling Ghost Ants

The key to the majority of eradication of Ghost ants is repeatedly applying high-density, highly attractive baits laced with toxicants. The ants take them back to the nest and distribute it to all colony members and the queens.

The first step would be looking for indoor and outdoor nesting spots. Follow the ant trail from inside your house leading to walls, garden areas, patio, porch, backyard or front yard. If you don’t see a trail leading outdoors, most likely they have found a place to nest inside your home already. You can try looking for them under the sink, between cabinets, books, under pots, inside the drawers and cupboards. In some cases, you may also find them behind walls, under the floor and other hard to reach areas of your home.

Remember to inspect the following:

• Trails for nests inside and outside the house.
• Look for outside nesting locations, like under the lumber, firewood piles, mulch, rocks, loose tree barks or other places of decaying matter.

Controlling Ghost ants Indoors; especially on hard to reach areas, you can use ant baits like Syngenta Advion Ant Gel.

Controlling Ghost ants Outdoors; you can use a non-repellant spray like Taurus SC. These non-repellant sprays are non-recognizable or undetected by ghost ants, so they don’t avoid them like other sprays. These sprays kill the ants on contact and by transfer. The worker ants bring back residue of the insecticide to the nest and transfer the insecticide to other colony members.

You can also treat the nest directly. Once you have located the nest outside the house, the best control method is the drench method. Get enough amount of the solution to reach the whole colony. You can use products like Bifen IT and pour it directly into the nest as per the manufacturers instructions.

Best Products to Get Rid of Ghost Ants

Inside the House:

If you have spotted the nest inside the house, the best management method is baiting. Using typical sprays will scatter the colonies, so are not recommended.

Recommended Bait Types:

Terro Liquid Ant Baits

Buy Now

Combat Max Killing Bait

Buy Now

If you need a spray to reach tiny cracks and spaces inside the house, we recommend:

Spectre PS

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Best Products for Outside the House:

Drenching the ant nest is the best way to get rid of the ants outside the house. Make sure to follow the instructions with caution.

Fuse Insecticide

Buy Now

Taurus SC

Buy Now

Preventing Ghost Ant Infestations

As with all invasive pests, prevention is always better and way easier, than cure. Management and control of the invasion pathways of Ghost Ants and the potential supply source is the best method for inhibiting infestation.

• Inspect food packages from groceries.
• Clean up food spills after meal preparation or consumption. The more crumbs or spills are out in the open, the more likely that these forager ants will enter the home.
• If you have a garden, keep the trees, shrubs and vines well-trimmed. Tree branches or shrubs can be bridges or highways for ants to enter your home.
• Set aside time to inspect and check for leaks, cracks, crevices and holes on the walls, foundations and beams of the house. Make sure to fill them with caulk or other materials that can close off these spaces.
• Put piles of wood or other house construction materials as far away from the house as possible.

Resources

• Wikipedia
• Ant Wiki
• Wiki Media Commons
• Entomology and Nematology l University of Florida
• Invasive Species Compendium CABI.Org

Habitat

Fire ants are ground-nesting ants that usually nest outdoors. Though the southern fire ant will sometimes nest in the wood or masonry of buildings, especially if it is in contact with the soil.
Red imported fire ants also usually nest outside, but will often build nests adjacent to foundation walls. Also, they can sometimes be found inside homes in areas with exposed soil, such as crawlspaces and bath traps. As a heat-loving ant, fireplace hearths and furnaces are also attractive to them. Often, red imported fire ants will be brought into a building via potted plants.
When fire ants do get inside, they are often searching for food or for new place to nest. They are attracted to electricity and can often be found in areas such as:

• Electrical junction boxes
• Air conditioners
• Gas and water meters
• Outdoor lights.

Outside the home, fire ant nests can be identified by the large mounds that they build. The mounds of the red imported fire ant are typically rounded, up to 18 inches high and 24 inches in diameter or more. Southern fire ant mounds are flatter and more regular, covering approximately 2 to 4 ft.² each. Both species prefer sandy soil that gets plenty of sun.

Behavior

Southern fire ants are omnivores. They feed on a wide range of food, including sugars, seeds, plants, and other insects. Like many ant species, the honeydew produced by aphids is an important food source for these ants. Southern fire ants have been known to remove insulation from phone and electrical wires, and have even been found chewing on clothing. However, this tends to happen more with clothes that have had food spilled on them. Although fire ants are capable of preying on other insects, they tend to scavenge more than they actively hunt.

Fire ants get their name from their sting. While they usually sting in defense of the nest, they can sting unprovoked. When a fire ant stings, it begins with a bite. Locking its mandibles in place in the skin of its victim, it then curls its body and delivers multiple stings with a stinger located at the tip of its abdomen. While stings can occur anywhere on the body, they are most common on the legs and feet, since most people are standing when they get stung.

Fire ant venom is an alkaloid, and causes a stinging sensation similar to that of a wasp. The burning sensation usually results in a raised bump or pustule and a reddening of the surrounding skin. However, in some people, an allergic reaction to the ant’s venom can cause a much more serious problem. In rare cases, people who are stung may go into anaphylactic shock. This tends to occur with people who’ve been stung by an ant or wasp in the past. In rare cases, anaphylaxis can be life-threatening if not treated quickly. Serious allergic reactions occur in approximately 2% of the population who get stung. It’s also important to note that anaphylaxis can happen even in people who are not allergic to the ants if they get stung enough times.

It’s estimated that around 30 to 60% of people who live in fire ant infested areas of the US are stung each year.

The red imported fire ant is also an aggressive species that will sting to defend its nest. These ants evolved in the rainforests of South America, and so they have a unique reaction to flooding. When water levels get too high, the ants form a raft from their bodies and drift on the water until they find dry land. Because they are outside of the nest, these ants are even more aggressive than usual and inject higher doses of venom when they do sting. This has caused deaths in hospitals and care homes where these aggressive ants enter and deliver multiple stings to bedridden patients.

Reproduction

Southern fire ants reproduce by swarming. Ant larvae fed a special diet become capable of reproduction and can be either male or female. Guided by pheromone signals, these winged ants will take to the air in the afternoon or evening of hot days between May and October. The lifecycle of fire ants is quite an interesting one. Fire ants will mate in the air, after which the males will die. The females will fly off to establish a new colony in the first suitable spot they can find. However, new queens can sometimes be found one to two miles from the nest they emerged from.

Red imported fire ants also reproduce by swarming. However, the colonies can be either monogyne or polygyne, meaning some have a single queen while others have multiple queens. Nests with a single queen reproduce only by swarming and are territorial. Polygyne nests, on the other hand, are not territorial and can reproduce both by swarming and by budding. Budding is a process in which a queen from an established colony will take a small group of workers and move out of the nest to begin a new colony elsewhere.

Once the queen has founded a colony, she will begin laying eggs. A single queen can produce more than 1500 eggs each day. It takes between 22 and 38 days for an egg to become an adult ant. For the first generation of workers, the queen regurgitates oils, lays sterile eggs as food, and even feeds the young her unneeded wing muscles.

The ants hatch from the eggs as limbless larvae. The larvae molt as they grow, shedding their skins through four larval stages. At the end of this process, the larvae pupate and emerge as adult ants. The first generation of workers then helps the queen raise the next generation.

Single queen colonies grow slower than multiple queen colonies, but end up being larger. Eighty thousand individual ants is typical for a single queen nest, but there may be as many as 250,000 individuals in the colony.

Colonies take a year or two to become fully mature. At this point, they begin producing reproductive ants of their own. Six to eight mating flights can take place between spring and fall, producing 4500 swarmers in one year.

Danger?

Fire ant stings are common in the areas where these species are active. In the southern US, most fire ant nests have a single queen and are therefore aggressively territorial. Stepping on or bumping into a fire ant mound will trigger an attack from the creatures. Stings are particularly common on children and household pets who don’t know to avoid the mounds.

Fatalities from fire ant stings are extremely rare. It’s estimated that the red imported fire ant has killed around 80 people since it was introduced to the US in the 1930s. Often, deaths occur due to allergic reaction, underlying health conditions, or immobile people being unable to escape from the ants. However, as an invasive species, red imported fire ants have had a severe effect on the populations of native wildlife. Ground-nesting birds are especially vulnerable to these ants, who often kill young birds in the nest.

Signs of a Fire Ant Infestation

In areas with a fire ant population, you may see foraging ants either outside or inside buildings. As colonies become established, visible mounds will start to form, usually in sandy soil outside. While the mounds make the ants potentially dangerous, they also make it easy to locate where ants are nesting. But remember, the ants can also nest in wood within the walls of a building. If you see lots of fire ants indoors, you may need to check your walls to make sure the ants aren’t nesting inside.

Controlling Fire Ants (including recommended product and Outdoor Control options)

Fire ant control can be difficult. Not only will the ants aggressively defend their nests, but reinfestation is always a possibility. While you may be able to remove them from your property for a season, there is a high risk that your property will be re-colonized by one or more queens during the next nuptial flight. For that reason, you may need to perform multiple treatments throughout the year to keep the fire ant population down.

Recommended product: Ortho Orthene Fire Ant Killer

Outdoor Control

There are multiple methods you can use to control fire ants outdoors, and each has their pros and cons. The best strategy is to use a mixture of different methods to achieve maximum control. The methods you can use on fire ants are:

• Direct injection of fire and mounds
• Broadcast application of bait
• Broadcast treatment with a contact pesticide

Directly injecting the mounds is the quickest way to kill fire ants, but make sure you use adequate protection to prevent ants from biting. You’ll also need to do a thorough inspection of your property to make sure you find as many mounds as possible. While larger mounds are easy to spot, you’ll probably miss some of the smaller nests that are mostly underground.

A broadcast application of bait delivers food that the ants will bring back to the colony and feed one another. While this can take longer, it’s a good way to kill off colonies you can’t find. Let the ants bring the poison into the nest for you. You’ll want to wait 7 to 10 days after applying bait before you interfere in any other way with the nests so that the ants have time to spread the poison through the colony.

A broadcast treatment with a contact insecticide will kill foraging ants on contact. However, killing foraging ants will not get rid of a colony by itself. For that reason, broadcast insecticide treatments are better used as a preventative measure to keep your property from being reinvested by reproductive fire ants. Multiple applications per year are usually needed. This is best done after you have already eliminated all the nests you can find on your property.

Best Products to Get Rid of Fire Ants

Inside the House:

The best products to use for treating fire ants indoors are baits. This avoids the need for spraying potentially harmful chemicals in your home. Also, it means that the ants will carry the poison back to the nest themselves, so you can achieve effective control without needing to know where exactly the ants are nesting.

Most bait uses a stomach poison to kill ants. However, there are baits on the market that combine a poison with an insect growth regulator. These powerful chemicals disrupt the lifecycle of the fire ant and sterilize the queen, making reproduction impossible.

Before using any fire ant bait in your home, make sure the label states it can be used indoors.

Recommended Bait Types:

Regular Bait:

Advion Ant Bait Gel

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Bait with insect growth regulator:

Extinguish Plus Fire Bait

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Ant Bait Stations:

Ant bait can be messy. That’s especially true when it comes to fire ants, since the bait often comes in the form of granules designed more to be spread outdoors than inside. That’s why ant bait stations can be a useful tool to control fire ants inside a building. Bait stations keep the bait in one place and let the ants come and go. This protects the bait from being spread around, and also keeps it safe from family pets or young children.

For more information on ant bait stations click here to see our full Ant Traps and Bait Stations Review.

Recommended Ant Bait Station:

Kness Ants-No-More Ant Bait Station

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Best Products for Outside the House:

Fire ants are best dealt with outside, since that’s where they are most likely to be. The best strategy for controlling fire ants outdoors is to begin with an outdoor bait. Then, once you’ve given the ants enough time to absorb the bait, target the mounds directly to destroy them with the pesticide application. Then, perform regular broadcast pesticide applications to kill any queens that attempt to recolonize your property.

Best Outdoor Bait:

Amdro Fire Ant Bait Granules

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Best Mound Treatment:

Ortho Orthene Fire Ant Killer

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Best Preventative Treatment:

Ortho Fire Ant Killer Broadcast Granules

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Preventing Fire Ant Infestations

• Regularly inspect your property to quickly detect any mounds that are forming.
• If you discover mounds, bait and then treat them directly with Ortho Ant Killer.
• Regular applications of a preventative treatment such as Ortho Broadcast Granules can help prevent new colonies from forming.
• Keep fire ants from getting inside your home by sealing up any cracks and crevices around air conditioning conduits, electrical sockets, gas and water meters, cracks in the foundation, and any other entrance points. Weatherproof silicone caulking is good for this task.
• Teach children to stay away from fire ant mounds to reduce the risk of them being stung.

Resources

• Wikipedia – red imported fire ant
• Wikipedia – southern fire ant
• Treatment of fire ant stings
• Fire ant bites
• Survey of anaphylactic reactions to fire ant stings