Most ants commonly found in Canada are not aggressive, though some can sting and bite if provoked. In general ants do very little damage and can be beneficial as they eat moths and other insects.
However, some types are known to invade homes and while the occasional unwelcome guest isn’t a big deal, things can get out of hand if they are not dealt with quickly and effectively. They may nest in wall voids, wood and pantries and continue to spread if they have access to steady sources of food and water.
In this guide we provide a step-by-step action plan for identifying, managing and getting rid of ants as well as reviews of the best ant killers (insecticides) available in Canada and how to make your own ant bait at home.
How to get rid of ants
1. Identify the type of ant
Common infesting ants in Canada
|Image||Ant||Size (mm)||Color||Diet||Antennae||Waist||Nesting||Most Active|
|Carpenter||6 to 25||Black to reddish-black||Insects, plants, protein and sweet food||Elbowed (bent)||1 node, no spines||Tunnels in damaged or decaying wood (doesn’t eat wood)||Night|
|Pharaoh||1.5 to 2||Translucent yellow to light brown and have a darker abdomen (back end).||Varied diet of sugars, proteins and fats, dead insects||12 segments, 3 segment club||2 nodes, no spines||Hidden in wall voids, under flooring, in furniture in kitchen and bathrooms||Day|
|Thief||1.5 to 2.2||Light brown or yellow||Grease, protein (meat, dairy, other ants’ food)||10 segments, 2 segment club||2 nodes, no spines||Near other ant colonies, rotting wood and soil||Day and night|
|Pavement||2.5 to 3||Pale brown to black, legs are lighter||Greasy and sweet foods, seeds, dead insects||12 segments||2 nodes, 2 spines||Cracks in garages, driveways and building foundations||Night|
|Odorous house||2.4 to 3.3||Brown to black||Sweets (honeydew), seeds, insects||12 segments||1 node,||Day and night|
|Argentine||1.6 to 2.8||Light to dark brown||Sweets (workers), proteins, grease||12 segments||1 node, uneven||Cracks in concrete, under leaves, shrubs or small stones||Day and night|
Thief ants are often confused for pharaoh ants. Thief ants’ antennae have only 10 segments on their antennae with only 2 segments on the club while pharaoh’s have 12 and 3 respectively. This can be tough to spot as they are so small so it can easier to look for the pharaoh ant’s darker back end or thief ant’s preference for grease and protein.
Carpenter ants are sometimes confused with termites, however, carpenter ants have bent antennae and a narrow midsection while termites have straight antennae and a thick midsection. Unlike termites, carpenter ants do not eat wood. They simply dig tunnels to create their nests and push the wood dust aside.
Argentine ants give off a stale musty smell when crushed while odorous house ants release a rotten coconut-like smell.
2. Observe their movements to determine the nest location
Follow the trail of ants in the direction that you see larger numbers back to their point of entry. The higher the traffic, the closer you are to the nest.
Ants that forage for food do so in a branching network pattern. As they travel from the nest to look for food, they leave behind pheromone trails to build branches in the network that lead to food sources for other ants to follow.
As they make more trips and other worker ants follow the same trail, the pheromone trail is strengthened – making it a stronger branch in the network. This is how they find their way back to the nest. In the case of pharaoh ants, they can leave either positive (food found) or negative (no food/danger) pheromones to alert others.
Each “trunk” leading from the nest divides into a number of branch routes depending on food availability. If a food source has been found, the path to it will be come the primary branch, while if food is scarce, workers will create many new branches in different directions.
3. Carefully remove nearby sources of food
Ants need consistent sources of water and food to survive and thrive so the easiest way to get rid of them for good is to cut off access which will make the area less desirable. Dispose of any infested food as ants can spread salmonellosis and dysentery.
Removing all other competing food sources to the bait will increase the likelihood that the ants take to it.
- Fix leaky plumbing or humidity problems
- Put all pantry items in sealed containers (eg. honey, peanut butter and baked goods)
- Clean up grease, sugar and crumbs on countertops, backsplash, floor and around appliances
- Clean and seal cooking oil containers
- Clean and dry dishes and leave the sink dry overnight
- Remove or cover pet bowls
- Rinse containers before putting them in the garbage or in recycling bins
Resist the urge to disinfect or wash the areas more than is required to remove the food sources. This can make the colony feel threatened and prompt them to relocate or split off into another colony (known as “budding”).
- Remove yard debris (especially decaying wood)
- Eliminate standing water
4. Place ant bait nearby
Baiting is the most reliable way to eliminate the entire colony.
You want to use a non-repellent ant bait – I’ve listed the best ones below. Insecticides such as Raid will kill the ants you see instantly on contact, but will not prevent the nest that is hidden nearby from producing new workers, and may cause it to bud as well.
Place one of the baits next to each of the highest-traffic foraging paths that you observed earlier and try to space them out a bit.
5. Wait and replace baits as needed
Now it’s time to be patient which is the hardest part. Resist the urge to kill or remove the ants you see or adjust the location of the bait.
The ants may continue to pass by the bait for a few hours while they follow their existing foraging paths, but they will eventually detect and check out the new food source.
The ants will eat it up and carry it back to the colony to regurgitate it to feed to larvae and other ants. The active ingredient (eg. borax) disrupts their digestion system and kills them slowly which gives them time to make a couple trips back and forth between the bait and the colony.
This process can take up to a couple of weeks, but in my case there was not a single ant in sight after 4 days.
6. Change up the bait
If the ants don’t take to the bait you set out it may be because you’ve misidentified them, have an appetite for something else or placed the bait in an area they’re avoiding for another reason. Depending on the time of year, feeding cycles and the current dietary needs of the colony, they may be more interested in:
7. Clean the area
Clean the areas where you saw the ants foraging with warm water and dish soap or vinegar. This will remove any pheromone trails and prevent the scent from attracting scouts back to the area. You may also try applying a deterrent such as cinnamon or peppermint oil, chili powder or lemon juice to turn them away.
8. Prevent ants from getting into your home
Seal the exterior and interior of your home including:
- Trim overgrown vegetation and tree branches that are touching or overhang your home
- Add weatherstripping around doors, replace door shoes
- Caulk cracks and crevices around windows, doors, vents and foundation
- Seal wall voids with spray foam
- Move wood piles away from your home
Best ant killers
- Best overall – Terro Ant Killer
- Best for protein feeding – Raid Dual Control Ant Baits
- Best natural and non-toxic ant killer – Diatomaceous Earth
Best overall – Terro Ant Killer
- Active ingredient: Borax, 5.4%
- Types of ants: sweet-eating (pharaoh, argentine, pavement, carpenter, odorous)
Terro’s liquid ant bait comes with 6 small low-profile plastic containers filled with an odourless clear solution and are ready to use and mess-free. All you have to do is twist or cut the top off and place it next to where you see the most ants. The ants will detect and check out the sweet liquid and the active ingredient borax will slowly disrupt their digestion system until they are dead. They should be left where children and pets can’t access them.
We recently had an infestation of what I figured to be pharaoh ants that had entered our kitchen through gaps in the backsplash and found a bottle of olive oil on the counter that hadn’t been completely sealed and cleaned off.
The ants were so small I wouldn’t have noticed if it hadn’t been for the sheer number of them. It was when I reached for the bottle of olive oil that I saw movement on and around it on our dark countertop. I immediately threw it out and cleaned the grease of the backsplash and stovetop.
While the ants initially continued to follow their existing paths to the remnants of the olive oil, with a few hours they found the bait. For the first 2 days, the numbers around the trap surged as they swarmed the bait (as you can see in the photo below). This was a bit disconcerting, but is actually good sign that the bait is working as intended. Many of the ants died in the fluid, but others climbed over them to get to it.
On the 3rd and 4th day, the numbers going to and from the bait declined and it appeared as though they were removing the dead ants from the bait (and I assume bringing them back to the nest?). By the 5th day, there was not a single ant in sight! I highly recommend giving this bait a try.
I plan to leave them out for a while yet and will update this section with any developments. Now it’s time to caulk the backsplash and seal any cracks I can find outside the house.
Best for protein feeding – Raid Dual Control Ant Baits
- Active ingredient: Abamectin, 0.05%
- Types of ants: protein-eating (thief, argentine, carpenter, pharaoh)
If your ants aren’t interested in sweet-based baits, the next approach you should try is to attract them with a protein-based bait.Thief ants for example are resistant to conventional ant traps, and are not attracted to sweets. They’re more interested in proteins such as meat, dairy and other ants’ food.
The active ingredient Abamectin is a delayed-action insecticide which gives the ants time to return to the colony and spread it to others through contact or food sharing.
Given the warning that the product contains peanuts it might be safe to assume that the protein portion is something similar to peanut butter.
Best natural ant killer – Diatomaceous Earth
Diatomaceous earth is a naturally occurring, non-poisonous sand made of silica that is extracted from the earth. It is made of many tiny fragments of fossilized remains of microscopic, aquatic organisms called diatoms. The silica absorbs the waxy coating from an insect’s exoskeleton causing it to dehydrate and die and the fragments have sharp edges which speed up the process.
“Food grade” DE means it contains a lower concentration (0.5 to 2%) of crystalline silica and considered safe for humans. Regardless of the name, we do not recommend eating it regardless of what you’ve read online or in reviews. There is no evidence that it has health benefits and inhalation can cause inflammation and scarring of your lungs so wear a mask while handling it.
It can be placed around areas you want to protect such as in cracks and crevices in your home to create a barrier that will keep out insects including ants. It maintains its effectiveness as long as it is dry and remains in place.
Residual outdoor insecticide
I was unable to find an insecticide in Canada that claimed long-lasting residual effectiveness such as Spectre 2 SC in the US.
There are products such as Ortho Home Defense Max Insect Control that appear to provide outdoor protection, but upon closer inspection this turns out to not be the case.
Home Defense Max Indoor & Perimeter Insect Control is an effective way to kill bugs and prevent them from coming into your home. Home Defense is now available with a Continous Spray Wand applicator.
- Effective indoor and perimeter insect control
- Use the new Wand for easy perimeter application. This creates a bug killing barrier.
I think the name and design of the product, wording of the description, and the inclusion of a professional-like wand applicator could lead some consumers to believe that it provides long-acting protection. However, this is not the case. If you look deep into the frequently asked questions section online, you’ll find an answer that confirms that the product is a contact insecticide and not a residual:
A “barrier” is “a fence or other obstacle that prevents movement or access” which I don’t think accurately describes the product. You also won’t find the word “outdoor” anywhere – only “perimeter” which when I was searching for an outdoor barrier spray made me immediately think of the outer perimeter around my home and it is classified by Home Depot and Canadian Tire as an Indoor/Outdoor product. What does perimeter mean in this case? Interior baseboards?
I think this is very misleading at best.
According to one reviewer (who gave it 1 star), there used to be a residual spray available in Canada and another user mentioned that this product used to create a barrier, but that it no longer does. The video accompanying the product on CanadianTire.ca doubles down on the supposed barrier effects:
Now, this is not to say the product doesn’t effectively kill a wide assortment of bugs when they’re hit with the spray, which it seems to based on many reviews.
However, if you have a serious invasion of pests and want long-lasting protection around your home, you’ll have to enlist the help of a pest control company that can apply a residual spray.
What is an insect growth regulator (IGR)?
An insect growth regulator is a chemical inhibits the life cycle of an insect by mimicking or inhibiting one of the hormones involved in the molting process which is necessary for growing insects to form a new exoskeleton that is larger than the previous one. This causes premature molting or interrupting the transformation from larva to adult.
Insect growth regulators (IGR) in Canada
While the number of IGRs legal for use in Canada is limited compared to the US, justification is typically provided and is often due to their health risks to humans. Unfortunately the distribution of those that are legal seems to be limited to commercial companies (not for sale to consumers) and/or only in larger quantities.
- Pyriproxyfen – 10% (under review) (eg. NyGuard IGR, Archer IGR)
- Thiamethoxam – 0.01% (2019 review by Health Canada limited its uses to protect bees) (eg. OPTIGARD® Ant Gel Bait Insecticide)
- Diflubenzuron (for cattle)
- Azadirachtin (for tree protection)
How to make DIY ant killer with borax?
To make your own ant bait, you’ll need to mix together 3 simple components:
- Food (protein, fat or sugar)
- Active ingredient (poison).
Making your own ant bait is easy and can be done using a common, readily available chemical compound available in the laundry or cleaning sections at grocery and hardware stores which is also useful for cleaning stains, mold and mildew and whitening and deodorizing laundry: borax. The most common brand you’ll see is 20 Mule Team Borax.
1. Measure the food source
Add 4 to 6 tbsp. of sugar to the plastic container you’ll use to hold the bait.
Sugar is the easiest source and likely to attract most common types of ants and this tester found that sugar was much more effective at attracting ants than honey or peanut butter. Other food sources that may be worth trying include confectioners sugar, corn syrup, lard, shortening.
2. Mix in the borax
Add 1 tbsp. of borax to the container and shake to mix well.
Ant baits you buy from the store will tell you exactly what the active ingredient is and how much of it is included. The recommended Terro Liquid Ant Bait states that it is 5.4% borax.
The concentration of borax is very important. Too little borax may not kill them reliably, while too much may make the bait undesirable or kill them too quickly that they don’t have time to bring it back to the nest. We suggest starting with the ratios made by the professionals as they’ve done much more testing.
3. Add warm water
Add 2 cups of warm water to make a liquid bait that has a concentration of approximately 5% borax.
- 2 cups of water = 492g
- 1 tbsp of borax = 27g
- 4 tbsp of sugar = 54.75g
To make a dry bait, add only a teaspoon of water to the dry mix and shake well to combine. This should bind the sugar to the borax while maintaining a granular form for the ants to pick up and bring to the nest. Add a bit more water if necessary (it should not become a syrup as it will not be accessible to the ants once it dries out).
Depending on the type of ant and the colony’s current needs, they may not take to the first type of food you try.
4. Place in a container near a high-traffic area
Place some of the bait in enclosed container(s) such as a plastic water bottle or yogurt container and puncture small holes in the plastic near the base. Label the container with a warning “contains borax” so everyone ext to the area you see the most ants. Keep the rest in a sealed container to keep it from drying out so you can re-apply to the bait stations.
A downside to making your own ant bait is that they tend to dry out quickly, requiring you to frequently re-apply new bait to the area. This is not a problem for the Terro Ant Bait in my experience as the solution has not dried out after being set for more than 2 weeks (with active air circulation and a dehumidifier in use).
Is borax/boric acid safe?
Borax and boric acid are both naturally occurring compounds known as borates – compounds containing the element boron and oxygen. Also known as Sodium Tetraborate, Borax is made up of sodium, oxygen and boron, while boric acid is a mixture of borax and other minerals such as boracite and colemanite.
According to Health Canada, Canadians are already exposed to boric acid in their diet, but that additional exposure from other sources should be reduced as much as possible to avoid overexposure which has the potential to cause developmental and reproductive health effects including disrupting the body’s hormones.
As of July 22, 2016, Health Canada advises Canadians to avoid homemade pesticide and slime (children’s craft) recipes using boric acid or borax.
Borax should not come into contact with your eyes or mouth and should not be ingested. As such, it should be kept out of reach of children and pets.
As a result, a number of pesticide products containing boron were banned in Canada. A list of which can be found here.
When to call a pest control company?
If you’re facing a severe infestation (multiple locations and/or separate instances) or you’ve followed the steps above and the ants keep coming back after multiple DIY attempts, it’s time to call a pest control professional.
Should I use an ant trap, bait, repellent or contact insecticide?
For most common types of ants, ant traps, repellent or non-residual contact insecticides should only be used as a preventative measure to attract and kill of the odd worker ant that finds its way into your home to forage for food to stop them from creating a pheromone trail into your home.
Using these products once many of the common ants that infest homes and gardens have multiple queens in each colony
What pesticides for ants are legal in Canada?
To find a registered pesticide, you can use the Health Canada online label database. The following are legal in Canada (concentrations are examples and do not constitute the limit):
- Borax – 5.4%
- Boric Acid – 5% (NiBan-FG)
- Abamectin – 0.05% (Advance375 A Ant Bait – 0.011%)
- Permethrin – 0.25%
- Imidacloprid – 0.03% (Ant-Trax)
- Hydramethylnon – 2.15%
- Disodium Octaborate Tetrahydrate – 6%
Researching how best to kill ants has probably led you to a number pesticides that are recommended and sold on US websites but seem to be unavailable in Canada.
Starting April 18, 2018, you can no longer bring unregistered pesticides into Canada from other countries such as the US if they are not equivalent to those already registered in Canada for personal use in or around your home (i.e., Domestic Class products). An equivalent pesticide is one that has the same active ingredient in the same concentration.
The following pesticides are not legal (unregistered) in Canada:
- Pesticide Label Search – Health Canada
- Pest Control Products Act – Department of Justice
- Use Pesticides Safely – Health Canada
- Pesticides in Canada – Consumer Safety
Over to you
Do you have an ant infestation in or around your home? We’re interested to know – what kind of ants do you think they are and what do you plan to do to control them? Help others by leaving your experience in a comment below!