Argentine ants are an invading species that used to live in Bolivia, southern Brazil, Argentina, Uruguay, and Paraguay. These days you can find them in South Africa, New Zealand, Japan, Australia, the US, and Europe, among other places.
It is believed that Argentine Ants (Linepithema humile) came to the mainland U.S. for the first time in New Orleans on coffee ships from Brazil in the late 1800s.
These days, you can find Argentine ants all over the southern states, as well as in California and Hawaii. In Arizona, Missouri, Illinois, Indiana, Maryland, and the Pacific Northwest, there are also some outbreaks that are not as common.
Like all ants, Argentine ants go through a process called full metamorphosis as they grow up. Depending on the temperature, development times can vary, but on average, eggs hatch in 28 days and ants become adults in 74 days.
How To Identify Argentine Ants
Since Argentine ants are so small, their color, tracks, and the fact that they don’t smell when you squash them are the best ways to tell them apart from other ants. Most of the time, people see the wingless worker ant, which is light to dark honey brown and 2 to 3 mm long.
In New Zealand, most home ants are black. When they are looking for food, Argentine ants are very busy. Most of the time, their paths are five or more ants wide, and they can go up trees and buildings. The White Footed Ant is the only type of ant in New Zealand that likes to climb trees.
Their trails aren’t as strong unless they’re moving a nest, in which case you would see them carrying their eggs. Argentine ants look a lot like Darwin Ants, which are also a type of bug.
There isn’t a strong smell of formic acid when you squash an Argentine ant, though. There is with some other ants, like Darwin Ants.
Where Have They Been Found?
It was in 1990 that Argentine Ants were first seen in Auckland. Since then, they have been seen in Northland, Waikato, Bay of Plenty, Hawke’s Bay, Wellington, Nelson, Blenheim, and Christchurch.
They have a lot of babies, but they don’t swarm (fly off to make new homes). In other words, they don’t spread very quickly (unless foraging queens are carried in boxes, potted plants, cars, etc.). But if a place is infested, it will have a lot of ant nests and a lot of them.
A few hundred meters per year is how fast they naturally spread. Their main way of getting to new places, though, is by moving nests and/or queens, which usually happens when garden tools or plants are moved.
Queen ants and workers that go out to find food can also be moved in cars. When Argentine ants fly away, they almost never do so.
Why Are They A Threat To NZ?
If you don’t do anything, Argentine ants will really bother your home and yard. Because they have so many nests”up to six per square meter”they eat a lot and will use almost any food source they can find.
It has been known for them to get into fridges, freezers, and screw-top jars! They are thought to be one of the worst home pests in California.
Native invertebrates are in danger from Argentine ants because they are very violent and kill and scare off other insects. They get up in trees and can kill bird babies in the nest.
Another thing they do is hunt for food, and they compete with animals like birds and insects that eat honeydew or nectar.
Aphids, scale insects, and other bugs that make honeydew are “farmed” by Argentine ants. These insects feed on plant sap and are protected by ants. Ants will even move the insects to new plants or parts of the plant.
This is a very big problem for organic farmers and farmers who use integrated pest management, because they depend on predators to keep these bugs in check. It has also been said that Argentine ants eat fruit fields directly, and that large groups of them can damage flowers, which makes it harder for fruit to set.
They are one of the worst citrus pests in Australia. They also do a lot of damage to grape, banana, and tomato crops.
Are Argentine Ants Dangerous?
Argentine ants are not dangerous to people. These ants, on the other hand, quickly multiply and attack other types of ants, as well as other bugs and even small animals.
What Do Argentine Ants Eat?
Argentine ants like sweet foods like syrup, fruit drinks, or plant fluids, especially honeydew that aphids make. They will eat almost anything, though, like meat, eggs, oils, and fats.
How to Get Rid of Argentine Ants
Any way to get rid of Argentine ants will probably involve some kind of man-made poison, which is a shame. They are hard to kill with natural remedies, and a whole group is too big for them to handle.
1. Bait Traps
The best and most effective way to get rid of Argentine ants and their nests on your own is to use ant food stations and traps. The hunters will bring the poison back to the nest, where it will kill the rest of the group. Their lures won’t get rid of all of them at once, but they should get rid of most of them over time. You can buy them in stores or make your own.
Bait Trap Tips:
- Sugar traps. Add a little Borax to a mixture of sugar and water to make your own sugar trap. Place it near where you’ve seen the ants.
- Traps for protein. The Argentine ant is drawn to both sugar-based and protein-based traps. In the spring, they like protein better. Two parts peanut butter and one half part borax can be mixed together to make a food-based trap. You can also add two parts honey to make a trap for both sugar and protein.
- If you want to catch Argentine ants with an ant bait trap, it needs to work slowly so that the workers have time to bring the bait back to the colony. Because of this, don’t use Borax by itself; instead, use it as part of a liquid trap. Also, don’t use any other type of powder insecticide.
- If ants figure out that a certain type of food is killing them, they will stop eating it. If your store-bought traps aren’t working, you may need to switch brands or change the recipe for the ones you make at home.
2. Argentine ant Pesticides
If you use a herbicide that is meant to keep Argentine ants away from a nest, they will leave and start new colonies, making your problem worse. Because of this, any pesticide used on these animals must not frighten them.
Pesticides that don’t kill the ants will kill Argentine ants, but they’re hard to get and follow strict rules. You probably won’t be able to buy these in stores without a license or approval. You will also have to pay someone to apply them for you.
3. Imidacloprid Fipronil Diatomaceous Earth
Diatomaceous earth is pretty much the only non-man-made option for Argentine ants. This is a substance made from the fossils of diatoms, which are single-celled creatures that look like plankton. Diatomaceous earth cuts open ants’ exoskeletons and dries them out within 24 hours, killing them instantly. This includes Argentine ants.
Diatomaceous Earth Tips:
- Putting diatomaceous earth over the nest is the best way to kill Argentine ants. Put a thin layer of paint on and around it. Any ants that leave or come in will die, which will make the colony and queens finally go hungry. The most important thing is that this will stop Argentine ants from moving and making new colonies. Since ants can only live without water for five days, it should be about a week before they’re all gone.
- Make a circle of diatomaceous earth around the nest if it’s not in the ground but under some wood, mulch, or other things that can’t be easily hidden.
- This will only kill worker ants and foragers and won’t solve the problem in the long run. You can also spread diatomaceous earth along Argentine ant trails to kill any that walk along them.
- Blow sand and bait traps can be used together. So that you don’t miss anything, you can either mix it into the food or use diatomaceous earth with bait traps.
- Wear safety gear. Wear safety glasses, gloves, and a mask when working with diatomaceous earth. Even though it might not be poisonous, it can irritate the skin and eyes if it comes in touch with them. If you breathe it in, it can make you short of breath.
- It’s better to have less. A thin layer of diatomaceous earth will work better and cause you less pain than a thick layer.
4. Stop The Spread of Argentine Ants
It’s important to remember that an Argentine ant colony can have more than one queen ant when you’re trying to get rid of them. If you try to destroy a nest, it might break up into smaller groups, which will make the problem worse. To do this, there are some things you should not do.
Tips to Prevent Argentine Ants From Spreading:
- Do not try to flood or kill an Argentine ant nest. Their nests aren’t very deep, and if any of them survive, they’ll split off and start new groups.
- Do not spray the nest. Normal pesticides sprayed on the nest will have the same effect as flooding: they will make more nests.
- Do not use a pesticide that keeps bugs away. If you try to get rid of Argentine ants with repellents, they will split up into different nests. This may make them panic and lay more eggs.
5. Exclude Argentine Ants From Your Home
There are a few things you can do to keep Argentine ants out of your home while you wait for the traps to work.
- Protect your home: Caulk should be used to seal any holes or crevices that ants might be using to get in, whether they are inside or outside. This will help keep them from coming inside.
- Cut back your plants: You can stop Argentine ants from getting in through another way by cutting back any bushes or trees that touch the side of your house.
- Put your trash away: The ants might be drawn to the smell of your trash. Putting something over it will hide the smell and make your house less appealing.
- Clean really well: If you clean your house really well, you can get rid of any spots, water, or other food sources that Argentine ants might be looking for.
FAQ About Argentine Ants
Can Argentine Ants Hurt Me?
Not at all. Argentine ants can’t sting, and their bites don’t hurt people. They won’t hurt you unless you are allergic to them. But they may crawl over dirty places like sewage, and if they come into your house, they can spread germs.
Will An Argentine Ant Colony Go Away On Its Own?
Not at all. In comparison to other species, Argentine ants live pretty long. Queens live for several years, and workers live for about a year. Queens and groups of workers will eventually leave the colony to start a new one, which will make your problem worse. If you let them, they’ll spread too fast to stop.
Why Do Argentine Ants Smell Bad When They’Re Crushed?
When many types of ants are crushed, they often give off a musty smell that only some people can smell. This is because they have formic acid in their blood, which is safe.
When To Hire A Pest Control Professional
In the event that you can’t get rid of Argentine ants in your yard or garden, it might be time to call a professional. The pest control people in your area can get rid of these bad ants and keep them away for good.