Ant hills on the lawn are a complete eyesore once they’ve been allowed to spread unhindered, but will they actually kill off all the grass if left unchecked?
Ants do kill lawns, but not by eating the grass. The soil mounds created as they build their nests can be over two feet across, and will eventually smother the grass. You can kill ants with store bought insecticide and organic methods, but preventing ant nests growing is the best option.
Let’s dive down into this subject in more detail, and discover how exactly ants damage your lawn (they don’t mean it honest!), and what we can do about it without killing the grass or harming our pets or kids.
Can Ants Destroy a Lawn?
We here believe in the rights of all people, animals, and insects. We all need to live our best lives – ants too – but not necessarily on our lawns.
Ants are social creatures. Communal. They build fascinating and elaborate structures underground. The trouble is the soil they dig up gets piled up around the outside of their little cities.
It’s the pile of dirt that’s the problem. Some ants have mounds that are up to 2 feet across. The mounds of dirt smother and kill grass plants.
Ants also like to feed on the fungi that surround grass roots – mycorrhizae. In a healthy lawn, this fungus colonizes around grass roots. Microscopically, they look like strings attached to roots. The fungal strings help the grass absorb water and nutrients, increasing lawn richness and health.
For some lawns, the problem is not the ants themselves – it’s the company they keep. Ants love honeydew. Honeydew is the sweet secretion of aphids, scale insects and mealybugs. Ants fascinatingly create aphid zombies by first tranquilizing them with their feet (!), then making sure they can’t escape by eating their wings.
As amazing as all this is, the trouble is that aphids, scale insects and mealybugs are not good for lawns and gardens.
If you’ve ever lived in Texas, you know all about fire ants. Fire ants don’t destroy lawns, they just kill any desire you have to be out on your lawn. Fire ants are a type of aggressive, stinging ant.
Fire ants in your lawn are a huge problem. You should check in with your local agricultural extension office to find the best – and safest- ways to deal with these pests.
Do Ants Actually Eat The Grass On My Lawn?
Nope. Ants don’t eat grass. But they do tunnel through it and feed on the good fungus that surrounds the roots.
A few tunnels in your lawn are a good thing. But the bigger the colony, the more tunnels, and the worse it is for your grass. At some point, your lawn will become OVER aerated. Water just runs through the tunnels and your grass starts to die.
How Do I Get Rid of Ants in My Lawn Without Killing The Grass?
This is tricky because so many of the ways to kill ants are also harmful to your grass. Or to your kids. Or to your pets.
There are many insecticides that will kill ants instantaneously and not hurt grass. If you need immediate action, be sure to check for ones that won’t hurt kids or pets.
Most experts say that prevention is the way to go with ants. Ants are persistent, so you have to be more persistent. When you are outside, mowing or gardening, watch for anthill sites. The minute you see one, disrupt them with a rake.
Can I Get Rid of Ants Overnight?
Yup. You can use an insecticide. If you want to kill them organically, though, you’ll have to play a long game.
When you first see an ant mound, get out your rake and scatter it. Many times, the ants will relocate to a spot where they won’t be disturbed (like your neighbor’s lawn).
For minor infestations, you can soak a big sponge in sugar water. Put it next to the ant hill. Leave it for a day, then wash out the dead ants. If you still have ants, put it out again.
Does Vinegar Kill Ants? (But Not Kill Grass?)
Vinegar’s natural acidity kills ants, but also grass. It will also kill any other, maybe beneficial, bugs you pour it on, so pour carefully.
Experts recommend using distilled white vinegar. Mix a solution using equal parts vinegar to water. Pour it into a spray bottle and spray the mound. You can also pour some directly into the mound.
If white vinegar isn’t doing the trick, another, stronger, vinegar you can try is apple cider vinegar.
Does Salt Kill Ants? (And Not Harm My Lawn?)
Salt is a desiccant. It kills ants by drying up their exoskeletons. Mix up a salty solution and spray it on the ants and it will kill them.
But, like vinegar, it will also kill your grass.
What Animals Eat Ants? (And Not Grass?)
The list of creatures that eat ants is long and most don’t eat grass. But you’re not going to love them in your yard. Like bears and coyotes. And – humans.
Ants are tasty snacks for many animals. For others, they are the only thing on the menu. Ants are relatively high in protein and fat. They are also – as you know – abundant. Ants have so many natural enemies that there’s a feeding behavior – myrmecophagy – that is defined by consumption of ants and termites.
Black widow spiders, jumping spiders and wasps love ants. Some pathogens, viruses and fungi love ants. Unfortunately, several other ant species eat ants, and often they are the aggressive, biting ones.
Then there are the humans that eat ants, although not usually in the US. In Australia, India, Thailand and Columbia, ants are a delicacy.
On the plus side, many bird species love ants. Flickers, sparrows, chickadees, nuthatches, grouse, and starlings all love ants. Lizards, armadillos, snails, toads, and snakes eat ants.
The nematode Steinernema Carpocapsae living in your lawn can also help with ants. This nematode is effective against fleas, ticks, ants, caterpillars, cutworms, and termites.
How Do I Get Rid of Ants in My Lawn Without Harming Pets?
There are several organic ways to get rid of ants in your lawn. Even though these methods are organic, try to limit your application to just the area of the ant’s nest.
One method uses canola oil – other sources use olive oil. Use a large bowl or bucket to make a solution of 1 1/2 tablespoons of canola oil, one teaspoon of mild dishwashing soap and one quart of water. Use a whisk to mix them all up. Pour some into a spray bottle. Then, spray the mixture onto the mounds. You can also pour some directly down the nest entrance.
Another method uses diatomaceous earth. Diatoms are microscopic aquatic organisms with skeletons made of limestone. Diatomaceous earth consists of many, many diatom skeletons. It looks like talcum powder. Here’s a video showing diatomaceous earth, from under a microscope.
Diatomaceous earth (DE) causes insects to dry out. When insects, like ants, crawl through diatomaceous earth powder, the sharp diatom skeletons act like glass on the insect’s exoskeleton. The ants die of dehydration, usually in 48 hours.
Make sure you buy food-grade DE. It’s non-toxic to pets – it’s even OK for them to roll in it – and it won’t harm grass. Be aware that sprinkling DE on your lawn may also kill other insects with exoskeletons.
Dawn dishwashing soap can also kill ants. It won’t hurt the grass or your pets. Try mixing a solution with 10 to 20 drops, or 1 teaspoon, of dish soap into a spray bottle filled with water.
Have some cornmeal? Try sprinkling cornmeal, or dry grits, next to the ant mound. Ants will eat the cornmeal, then it will expand in their stomachs, killing them.
One smart method involves boiling water – but not on your lawn, which will kill the grass. Get a large flower pot, set it away from grass, pets and kids, and bait it with a piece of fruit. Once you have plenty of ants swarming the fruit, carefully pour the boiling water over the ants. Repeat as many times as necessary.
Ant hills on the lawn are bad news, and although you can kill the ants with insecticide or organic solutions, it’s best to try and nip the problem in the bud by stopping the ant hills taking hold in the first place.
This means keeping your eyes peeled for those tell-tale little hills of soil when you’re out mowing the lawn or gardening – then acting quickly to kill the ants so the nest can’t grow.
If you find yourself playing catch-up, then even when you’ve killed the ants you’ll still have to flatten and re-seed the ant hills to return your lawn back to its former glory.
So remember, when it comes to ants on your lawn, the best defense is staying ahead of the game! 🙂
Homeowner and property investor Larry Jones founded Take a Yard in 2020 to bring you the very best outdoor living content, based on his years of experience managing outside spaces. Read more >