Finding an anthill on your property can feel unsettling. Whether it’s a small mound in the lawn or a line of ants marching from a crack in your baseboard, it’s natural to be concerned.
The good news is that most ant situations are manageable and don’t point to a major infestation. The key is to correctly identify where the problem is and what kind of ants you're dealing with. An anthill far out in the yard is very different from one found inside your home or pressed up against the foundation.
This guide will walk you through how to assess the situation calmly, determine if you can handle it yourself, and know when it’s the right time to call a pest control professional.
Image Alt: A close-up view of a common black ant anthill in a garden.
First, Identify the Anthill's Location
Before you do anything else, the first step is to figure out exactly where the ants are setting up camp. Is the anthill inside your home, right against the foundation, or further out in the yard? This single piece of information will guide all of your next steps.
Take a slow walk around the inside and outside of your home. Pay close attention to baseboards, window frames, and the edges of your foundation. A flashlight is a great tool for checking darker areas like crawl spaces, behind appliances, and under decks. Once you’ve located the source, you can decide how to proceed.
What to Do About an Anthill Inside Your Home
Finding an anthill or a steady trail of ants indoors requires more immediate attention. Ants inside the house are either nesting within your walls or have found a reliable food source and a clear path inside.
Step 1: Look Closely at the Ants
Not all ants are created equal. Some are just a nuisance, while others can cause structural damage or deliver painful stings. Observe the ants from a safe distance.
- Do they look large? Ants larger than a quarter-inch, especially if they are black, could be carpenter ants. Look for piles of fine sawdust (called "frass") near their trails, which indicates they are tunneling through wood.
- Are they red and aggressive? Reddish ants that swarm and sting when disturbed are likely fire ants. Their stings are painful and can cause allergic reactions.
- Do they bite? While many ants can bite, if you’ve experienced a particularly painful bite, it’s worth being cautious.
When to Stop: Call a Professional Immediately
If you suspect you have carpenter ants or fire ants, do not try to treat them yourself.
- Carpenter ants can cause significant structural damage by carving out nests in the wood framing of your home. A professional is needed to locate and eliminate the entire colony.
- Fire ants are highly aggressive and their stings can be dangerous. Eradicating an indoor colony requires specialized products and expertise.
For these situations, the safest and most effective solution is to contact a licensed pest control professional.
Step 2: A Safe DIY Fix for Minor Indoor Ants
If the ants are small, non-stinging, and don't appear to be carpenter ants, you can likely handle the issue yourself.
- Use Ant Bait: Instead of spraying the ants you see, use ant bait stations or gel. The worker ants will carry the poisoned bait back to the nest, which eliminates the entire colony, including the queen. Place small, pea-sized drops of bait along their trails, but keep them out of reach of children and pets.
- Seal Entry Points: Use caulk to seal any small cracks or holes you see along baseboards, window frames, or where pipes enter the home. This blocks their path inside.
- Clean Thoroughly: Wipe down kitchen counters, sweep floors, and store food in airtight containers. Removing their food sources makes your home far less attractive to them.
- Monitor for 7 Days: It can take several days for the bait to work its way through the colony. Be patient and resist the urge to spray the ants you see—they need to take the bait back to the nest. Keeping a simple log in an app like Casa can help you remember when you started the treatment and track if activity is decreasing.
If you still see significant ant activity after a week, the colony may be larger than the bait can handle. At this point, it's time to call a professional for a more thorough assessment.
How to Handle an Anthill Outside Your Home
Outdoor anthills are a normal part of the ecosystem. Often, they can be left alone. However, if they are too close to your house or in a high-traffic area, you may need to intervene.
Step 1: Check Its Proximity to Your Foundation
Measure the distance from the anthill to your house.
- Is it within 3 feet of the foundation? An anthill this close poses a risk. The colony could easily expand and find its way inside your home through tiny cracks in the foundation.
- Is it more than 3 feet away? If the mound is far out in the yard and not bothering anyone, the simplest option is often to leave it be.
Step 2: For Anthills Close to Your House
If the anthill is within that 3-foot zone, take a closer look at its size and the amount of activity.
- Is the mound smaller than 6 inches tall?
- Is ant traffic light? (If you watch for a minute, do you see fewer than 20 ants coming and going?)
If you answered yes to both, you can try a low-impact DIY treatment. If the mound is large or bustling with activity, the colony is well-established and more difficult to remove. In that case, your best bet is to call a pest control professional.
DIY Deterrent for Small, Nearby Anthills:
- Apply Diatomaceous Earth: This natural powder, made from fossilized aquatic organisms, is harmless to humans and pets but deadly to insects. It works by absorbing the oils from their exoskeleton, causing them to dehydrate.
- Sprinkle a thin layer of food-grade diatomaceous earth over the mound and the surrounding soil.
- Gently disturb the top inch of the anthill with a small rake or shovel and apply another light layer.
- Keep the area dry for at least 48 hours, as the powder is most effective when it isn’t wet.
- Check for activity after 3 days. If the ants are gone or significantly reduced, your work is done. If activity is still high, it's time to call a professional.
Image Alt: A person wearing garden gloves sprinkles white diatomaceous earth powder on an anthill in their lawn.
Step 3: For Small Anthills Far from Your House
If a small anthill is in a place where you don't want it—like the middle of a play area—but is far from your house, relocation is a good option.
- Prepare a bucket with a few inches of soil from a distant part of your yard.
- Quickly scoop the top 6 inches of the anthill into the bucket using a shovel.
- Carry the bucket at least 50 feet away to an undisturbed area, like a back corner of your property.
- Empty the bucket and gently flatten the soil.
- Rake the original spot level and water it lightly to wash away any remaining scent trails.
- Check the original location in two days. If the ants have rebuilt, they are more persistent than average, and it may be worth calling a professional to discuss other options.
Typical Time and Cost
- DIY: Treating a minor ant issue yourself is very affordable. Ant bait or diatomaceous earth typically costs between $10 and $20. The process requires a small amount of active time and a few days of monitoring.
- Professional: Hiring a licensed pest control professional for a one-time ant treatment generally ranges from $150 to $350, though costs can vary based on your location and the severity of the problem.
You're Prepared to Handle It
Dealing with ants is a common part of homeownership, and now you have a clear plan. By identifying the location and assessing the situation, you can make a confident decision about whether to tackle it yourself or bring in an expert.
Managing a home means knowing what to watch for and how to respond. With the Casa app, you can track your home maintenance tasks, get timely reminders, and access clear advice for challenges just like this one. Download Casa today to feel more prepared for whatever your home sends your way.
