One of the most prolific insect pests is the Argentine ant. If this tiny invader shows up in your lawn or garden, you need to know how to get rid of it and fast, before it’s too late. With these unruly ants come parasites such as mealybugs and aphids that will turn your poor garden into a buffet.
Eliminating an Argentine ant infestation is difficult but not impossible. Knowing how to get rid of them is half the battle. Thankfully, there are methods to keep them away from your lawn or garden and to get them out once they arrive. Read this helpful guide for tips on how to get rid of Argentine ants and keep them from coming back.
What Are Argentine Ants?
Argentine ants, also known as Linepithema humile, are a dark brown invasive species of ant from Argentina. They’ve spread worldwide and are primarily found in California, Arizona, Illinois, Maryland, Missouri, Oregon, Texas, and Washington in the United States.
Argentine ants are unique among ants in that colonies will not attack each other and will in fact cooperate to create supercolonies. Combined with their lack of natural predators, this allows them to proliferate wildly and without contest. They also bring along other harmful pests, cultivating mealybugs and aphids to feed off their honeydew.
Argentine ants pose a great threat because they push out other native insect species that predators rely on for a food source and eat up food and water resources. This upsets local ecosystems and disrupts the food web, which can lead to beneficial pollinators and other garden critters disappearing.
How to Get Rid of Argentine Ants
Unfortunately, any ant control method for Argentine ants is more than likely going to involve some form of synthetic chemical. There are few organic solutions that will kill them, and they’ll do little against an entire colony. Thankfully, this shouldn’t mean exposing your plants to harmful pesticides.
Ant bait traps and ant bait stations are the best and most effective method you can use to get rid of Argentine ants and their nests by yourself. The foragers will carry the poison back to the nest, killing the rest of the colony. Baits won’t get rid of all of them at once right away, but it will hopefully eliminate them over time. You can buy them commercially or make your own.
Bait Trap Tips:
- Sugar traps. To make your own sugar trap, mix a tiny amount of Borax into a mixture of sugar and water and leave it out near where you’ve seen the ants.
- Protein traps. Argentine ants are attracted to both sugar-based traps and protein-based traps. They prefer protein in the springtime. To make a protein-based trap, mix two parts peanut butter with half of a part of Borax. You can also add two parts honey for a combination sugar and protein trap.
- Any ant bait trap you use against Argentine ants needs to be slow-acting so that the workers have the opportunity to bring it back to the colony. For this reason, use the Borax as part of a liquid trap and not by itself, and do not use any other kind of granule insecticide.
- If ants catch on that a certain kind of food is killing them, they will stop eating it, so if your traps have stopped working, you may need to switch brands of store-bought traps or change your recipe for homemade ones.
Argentine Ant Pesticides
Any repellent pesticide used on an Argentine ant nest will cause them to spread out and multiply into additional new colonies, worsening your problem. Therefore, any pesticide used against these creatures needs to be non-repellent.
There are some non-repellent pesticides that will work against Argentine ants, but they’re few in number and very controlled. You likely won’t be able to buy these commercially without some form of license or certification, and will need to hire a professional to apply them for you.
Argentine Ant Pesticides:
Just about the only non-synthetic solution for Argentine ants is diatomaceous earth. This is a substance formed from the fossils of diatoms, single-celled organisms resembling plankton. Diatomaceous earth kills ants on contact, including Argentine ants, by cutting open their exoskeletons and dehydrating them within approximately 24 hours.
Diatomaceous Earth Tips:
- The most effective way to kill Argentine ants with diatomaceous earth is to cover the nest. Apply a light coating on and around it. Any ants that leave or enter will die, eventually starving the colony and queens. More importantly, this method will keep Argentine ants from spreading and splitting off into more colonies. It should take roughly a week before they’re all dead since ants can survive for no longer than five days without water.
- If the nest is not in the soil and is instead underneath some wood, mulch, or other debris that cannot be reasonably covered, surround it with a perimeter of diatomaceous earth.
- You can also spread diatomaceous earth along Argentine ant trails to kill any that walk along it, but this will only get worker ants and foragers and will not solve the problem long-term.
- You can use diatomaceous earth and bait traps together. Mix it into the bait or use an application of diatomaceous earth in conjunction with bait traps to ensure you’re covering all your bases.
- Use protective gear. When using diatomaceous earth, wear breathing protection, eye protection, and gloves. It may not be toxic, but it can irritate the skin and eyes if it comes into contact with them and cause shortness of breath if inhaled.
- Less is more. A thin coating of diatomaceous earth is more effective than a thick one, and will result in less irritation for you.
Prevent Argentine Ants From Spreading
When attempting to eliminate Argentine ants, it’s very important to keep in mind that one colony can have multiple queen ants. If you attempt to destroy a nest, it may separate into smaller colonies and make your problem worse. To this end, there are a few things you need to avoid doing.
Tips to Prevent Argentine Ants From Spreading:
- Do not try to drown or flood an Argentine ant nest. Their nests are shallow, and any survivors will branch off and form new colonies.
- Do not spray the nest. Spraying the nest with typical insecticides will have the same effect as flooding, making the nests multiply.
- Do not use a repellent insecticide. Any repellents used to try and control Argentine ants will cause them to split off into multiple nests and may make them panic and increase egg production.
Exclude Argentine Ants From Your Home
If Argentine ants are showing up in your home, there are a few things you can do to keep them out while you wait for the traps to work.
- Seal your home. Sealing any cracks or crevices that ants may be using as an entry point, both inside and outside, with caulk will help prevent them from coming inside.
- Trim your foliage. Trimming any bushes or trees so that they don’t touch the side of your house will take away another avenue Argentine ants may be using to enter.
- Cover your trash. The smell of your trash may be attracting the ants. Covering it will suppress that smell and make your house less inviting.
- Do a deep clean. Thoroughly cleaning your house will remove any stains, water, or other food sources that may be attracting Argentine ants.
What Causes Argentine Ants?
There are a few reasons Argentine ants might be invading your home or garden. They naturally spread out over time, but certain things can attract them and cause them to make your spaces a nesting ground.
Argentine Ant Causes:
- Moisture. They’re attracted to moisture, so birdbaths or puddles in your yard could be bringing them in.
- Food. Any stray food in your house could also be attracting them, even dried spills.
- Weather. Like many creatures, Argentine ants prefer a warm environment. If it’s cold out, they may seek shelter in your home.
- Parasites. If you have an infestation of other insects that Argentine ants typically coexist with, such as mealybugs or aphids, the ants may be attracted to them.
How to Prevent Argentine Ants
There are a few things that you can do to keep Argentine ants from invading your home or garden.
Preventing Argentine Ants:
- Eliminate food and water sources. If there’s no food or water for the ants to feed off of, they’re less likely to come to your home or garden. Don’t leave out any standing water or food, including rainwater, and cover any outdoor garbage.
- Keep your yard clear of debris. Argentine ants will nest in wood piles, mulch, grass clippings, and other yard debris. Keeping it clear and storing any necessary firewood away from your home can keep them away. Twenty feet should be sufficient.
- Keep your home clean. Cleaning any spills quickly, regularly disposing of garbage, frequently wiping down countertops and other surfaces, and keeping food in sealed containers will prevent your home from attracting Argentine ants.
- Protect your yard and the perimeter of your home. As long as ants haven’t already moved in, you can keep them away with regular treatments of long-lasting insecticide sprays or diatomaceous earth that will kill them on contact and deter them from your home.
FAQ About Argentine Ants
No. Argentine ants cannot sting and their bite is harmless to humans. Unless you are allergic, they pose no personal danger to you. That said, they may crawl over unsanitary areas such as sewage, which can spread germs in your house if they enter it.
No. Argentine ants are relatively long-lived compared to other species, with queens living for several years and workers living for approximately one year. Eventually, queens and groups of workers will leave the colony and create a new one, worsening your problem. If you let them, they’ll spread uncontrollably.
It’s common for many species of ants to release a musty smell when they’re crushed, but only some people can smell it. This is due to the formic acid inside their bodies and is harmless.
Call in the Cavalry
If your yard or garden is infested with Argentine ants and nothing seems to get rid of them, it may be time to contact a professional. Your local pest control experts can rid your yard of these devilish ants and keep them away for good.