Originally published on May 22, 2020.
Each year during the summer months when we are out on the lawn, enjoying the weather, we know that one person who is bound to find the fire ants. Who knows that person may actually be you!
These imported fire ants inflict painful stings and create these unsightly mounds across the lawn and landscape. Most of the time though, it is the mounds that are level with the lawn that end up getting us when we are outside enjoying our lawn and playing catch.
Fire Ant workers foraging for food.
There are a variety of products and methods to help control these pests. Unfortunately, there is no treatment that will permanently eradicate them from your lawn. The product or method that you choose to use in your lawn will depend on a variety of factors. How many mounds do you see? Do you have pets and/or children who enjoy the lawn? Do you have them near a pond? These are just some of the questions you will need to ask yourself when choosing a control method for your home.
As always, it is important to read and understand the label of the product you will be using as your control method. It is also important that you feel comfortable and can apply as directed on the label. Finally, make sure that you are using all labeled personal protective equipment when applying any of the products below.
Fire ant mounds are unsightly in the lawn but will also kill the grass
where they are formed leaving bare spots once the colony is controlled.
Baits are a pesticide that is combined with material that fire ants will consume as food. This product will be collected by the ants and brought back to the mound. It is important to use fresh bait, and to apply it when the ground and grass are dry with no rain forecasted for at least a 24-hour period after application. It is also important to apply the bait at a time where the worker ants are actively searing for food. Test a small amount of bait (about 1 tablespoon) on the ground and wait approximately 30 minutes to determine if the worker ants are actively foraging. Research shows that most of the foraging takes place when the temperature is between 70° to 95° F.
Baits are typically spread with a handheld or walk behind spreader. These are safer to use around a water source, such as a pond, just remember to apply with the pond or water source at your back so you do not spread into the water accidentally. Remember to look at the label to locate the spreader setting to apply this product. It will also list the amount of square feet that it will cover. It is important to remember that baits are slower acting and may take several days for you to see results. Also, make sure to follow the label recommendations on how long to keep anyone off the lawn after application.
These products, such as those containing acephate, are applied as a dry dust. The ants walk through the treated soil and get dust on their bodies. They then transport the insecticide directly into the mound. Within a few days the entire colony should be killed. When using a dust, it is important to distribute the recommended amount evenly over the undisturbed mound. Some of these dusts are white or yellow in color and can be very appealing to a pet or child. Please make sure to not allow pets or children on the lawn unattended as they both may be curious as to what this may be. Again, follow all label recommendations when using these products.
These are exactly what they sound like. A mound drench is where the insecticide is mixed with water, per the label rate, and then applied in sufficient volume to penetrate the entire nest. Generally, about 1 gallon of diluted mixture is poured gently over the top of each mound. This type of control is difficult and time consuming if you have several mounds in your lawn but is a great choice if you have no way of keeping a pet off the lawn.
One of the most common control methods that I have seen recently is the use of granules. These products are insecticides in granule form and are spread on each individual mound. These are most effective if you sprinkle the amount recommended on the mound and directly adjacent to the mound itself.
There are a few active ingredients used in fire ant control products, such as boric acid, pyrethrin, pyrethrum, rotenone, citrus oil extract and diatomaceous earth. Diatomaceous earth, a natural silica-based dust will kill some ants, but it rarely eliminates ant colonies when used alone. If using these products, you will want to avoid breathing in the dust particles.
Most home remedies do not work well, and in most cases end up only feeding the pests that you are trying to kill. For example, spreading grits or laying orange peels on a fire ant mound only provide a food source for them. Shoveling one fire ant mound and placing it on another in the attempt to force one ant colony to kill the other is not effective. Finally, do not use gasoline or other petroleum products for fire ant control. While many of the products will kill fire ants, they are extremely flammable, will kill grass and other plants, and it is extremely bad for the environment.
It is important to remember we are controlling these fire ants and it may take several applications or methods to control them in your lawn depending on how severe the ant population may be. We always want to use all the products discussed here in the most safe and responsible manner. This is done by following all label recommendations on the product because remember the label is the law.
It is my hope that if you are the one person that always seems to find the ants in your yard, one of these methods will help save you from getting stung at least one less time in the future. If you have any questions about these control methods please give Mark Carriere, County Agent, a call at the Pointe Coupee Extension Office, (225) 638-5533, or send him an email at mcarriere@agcenter.lsu.edu. More information on this and numerous other topics can also be found by visiting the LSU AgCenter website.