How to Get Rid of Odorous House Ants | Proven and Effective Methods

Odorous house ants live in cracks, crevices, or wherever they find safe shelter and easy access to food. More established colonies of these ants can be a source of nuisance and they can also bring some diseases. Therefore, it’s important to act immediately to eliminate an infestation of odorous house ants before any problems arise.

To get rid of odorous house ants first inspect the area to locate the ant colony. This would usually be near a source of moisture. Apply soapy water to eliminate any pheromone trails. Now you can use ant baits so any remaining ants would be attacked and killed by it. Fixing the source of moisture will prevent them from coming back.

In the following section, we have given a detailed control guide for odorous house ants and prevention tips. In addition, we also provided you with some DIY natural methods to get rid of odorous house ants infestation. Let’s begin!

What Are Odorous House Ants?

Odorous house ants (Tapinoma sessile) are very small ant species. They are also known as stink ants or coconut ants. These ants are 2.4 mm to 3.3 mm (3/32″ to 1/8″) long and have a dark brown to black appearance. The antennae of odorous ants have 12 segments and the thorax appears asymmetrical when viewed from the side. 

These ants have a caste system (workers, male and female reproductive), and each hierarchy performs a specific task. Male winged odorous house ant is responsible for only the mating process during the breeding season.

The queen lays eggs to establish a colony, while the workers do most of the heavy work. Worker ants collect food and support the entire colony.

Odorous House Ants Queen

Each colony of odorous house ants can contain multiple active queens. The survival of the colony depends upon the queen who lays eggs. A queen lays about 350 eggs in the course of a season and has a life span of more than one year.

Odorous Ants With Wings

Male and female reproductive odorous ants are also known as winged swarmers. These ants can be seen near light sources during the mating season. They swarm during the spring or early summer season but only for a short time period.

After mating, the female queen flies back to the original nest or to a new nesting site to establish a new colony. The male reproductives usually die (in 1 week to 10 days) after mating.

Where Do Odorous House Ants Live?

Odorous house ants can be found in different parts of North America, including Canada, Mexico, the Atlantic Coast, the West Coast, and different areas of New England. They build their shelters in hollow trees, under stones and moist soil, moist logs, firewood, and debris, as well as in cracks, bricks, or under pavements outdoors.

Indoors, they live in wall voids, cracks, behind cabinets, near water heaters or pipelines, under kitchen or bathroom sinks, beneath plant pots, or anywhere near moisture. They move indoors during extreme weather or heavy rain.

Do Odorous Ants Have an Odor?

The odorous house ants produce a foul smell like rotten coconut when they get squashed and that is exactly why they are named odorous ants, coconut ants, or stinky ants. The odor from these ants is comparable to some rotten foods due to similarities with the penicillium mold smell.

Are Odorous House Ants Dangerous?

While odorous house ants are not considered dangerous, larger infestations can be a nuisance and they can carry harmful microorganisms into your home from contaminated sites. The queens of these ants are highly tolerant of cold and heat and can survive for up to two months without food or water, making eradication more difficult.

It’s important to address an odorous house ant infestation during the early stages of development to prevent further problems.

Do Odorous House Ants Bite?

The odorous house ants are not aggressive in nature. They do not have a stringer and usually do not bite. Although, they will defend their colony against invaders and can bite to protect themselves just like other ants. However, their bites don’t cause much pain.

Related: Ants in My Garage | How to Get Rid of Ants in Garage

What Do Odorous House Ants Eat?

Odorous house ants can eat both sugar-based and greasy (protein) based foods, but they prefer sweet foods such as jams, jellies, juices, cakes, donuts, fruits, pastries, and dairy products.

They are attracted to spilled food on kitchen floors or counters and remain active during both day and night. In outdoor settings, they forage for honeydew-producing insects and rotten food items, as well as prey upon aphids, mealybugs, and other insects.

Related: What Do Ants Eat? | Ant Feeding Habits

Odorous House Ants vs Carpenter Ants: Difference

The odorous house ants and carpenter ants can be differentiated by their appearance and size. The odorous house ants are smaller (up to 3 mm or 1/8″ long) than carpenter ants (up to 12 mm or 15/32″ long). Odorous ants are dark brown to black in color, while the other hand, carpenter ants have a reddish-black body.

Carpenter ants produce formic acid when they get crushed which smells like vinegar whereas smashed odorous ants produce a rotten coconut-like smell. The odorous house ants do not cause any structural damage whereas carpenter ants excavate wooden structures to build their shelters.

What Attracts Odorous Ants?

When trying to flee the flooding of its shallow earth nest, this ant is most likely to invade dwellings following periods of heavy rain. They will build warm, moist nests indoors, such as those inside walls, under sinks, and near hot water pipes. 

Although this ant prefers sweets like fruit juices and pastries, it will also eat a variety of things like meats and pastries. Due to changes in the environment, these ants usually relocate their nests during the summer.

Signs of Odorous Ants Infestation

The fragrance of odorous ants is the easiest way to tell if you have them. They typically move in lines, but if they feel threatened or disturbed, they may rush wildly while exhaling as they do so.

Although decaying coconuts are the most common comparison, several people have also connected their smell to a peculiar pine scent.

How to Get Rid of Odorous House Ants: Step-by-Step Instructions

The odorous house ants are one of the most common house-invading ants. Our integrated pest management strategy will help to permanently eliminate these ants in your house and outdoors.

Our guide includes different steps such as inspection, treatment (using one or more methods), and tips for preventing the re-establishment of odorous house ants. Now let’s start with our detailed guide!

Step 1: Inspection of Infested Sites

The first step is the investigation or inspection of potential nesting sites, entry points, and mounds of odorous house ants. Inspect all of the wall voids, cracks, and dark and narrow spaces near moisture which can provide shelter to odorous house ants. 

Step 2: Application of Insecticide

After the inspection of the infested areas, choose one or multiple treatment methods to get rid of the odorous house ant colony. In the following sections, you will find several treatment methods that will help you to eradicate them effectively.

Ants Baits or Ant Traps

Ant baiting is a powerful and effective method for eliminating odorous house ants both indoors and outdoors. Simply place ant bait at entry points, near ant trails, and close to nesting sites. The ants will consume the bait and take it back to their nests, killing the entire colony, including the queen.

This process can take time to take effect. There are different types of commercially available ant baits, including sugar-based and protein-based baits, that work on odorous house ants.

Ant Baits and Traps

Indoor and Outdoor Insecticide Sprays

Indoor and outdoor insecticide sprays can also help to treat odorous house ant infestation. Apply the ant spray on the exterior walls, inside of the holes, and cracks, at the ant trails, near the entry points, and at nesting sites.

Related: Best Natural Ant Sprays | Kids and Pet-Friendly Sprays

The insecticide sprays show instant results and provide excellent protection against ants. But they will only work on the ants that you can see in front of you. This is why baits are a better option when dealing with a large colony.

Best Insecticide Sprays

Dust Treatment for Odorous House Ants

Insecticide dust is also very effective against odorous house ants. The insecticide powder kills the ants directly when it comes in contact with them.

Apply the dust inside cracks and wall voids, behind cabinets, inside narrow spaces, and at all the potential nesting sites. You can also use professional dusters to make the process easier.

Dust Treatment

Step 3: Prevention

The best way to prevent odorous house ants from invading or re-establishing in your home or yard is to maintain cleanliness and remove factors that can attract them. Remove all moist wood shavings, wood logs, mulches, brick piles, and debris from your yard.

Consider growing ant-repellent plants like catnip, lavender, or peppermint. Cut tree branches close to property walls to prevent ants from entering your home. Inside your home, seal all holes, cracks, and spaces that could provide shelter for odorous ants.

Keep your kitchen and bathrooms dry and fix leaky pipelines. Clean your kitchen regularly and promptly dispose of food leftovers and crumbs after every meal. Store food items in covered containers and refrigerate them when possible.

How to Get Rid of Odorous House Ants in Walls?

Odorous house ants often nest inside wall voids, wall cracks, or holes. The most effective way to get rid of them in walls is to use insecticide dust or ant baits, or a combination of the two. Apply the dust inside the wall cracks to kill most of the ants instantly.

If you suspect there is a nearby colony, use ant baits near the ant trails and entry points. Ants will take the bait back to their nest, killing the entire colony. You can also use sprays to treat the infested wall voids, following the manufacturer’s guidelines and read the labels carefully for the best results.

How to Get Rid of Odorous House Ants Naturally: Instructions

There are several ways to get rid of odorous house ants naturally. For example, you can prepare homemade insecticide sprays, ant baits, or traps. These methods are inexpensive and do not require toxic chemicals.

Ant Repellent Plants

You can plant different ant-repellent herbs in your garden or around the boundary wall of your house to deter odorous ant infestations. Some of the ant-repellent plants are rosemary, peppermint, thyme, lavender, sage, catnips, garlic, pennyroyal, cinnamon bark, etc.

You can also use the essential oils of these plants to prevent the odorous ants from invading your house. To create an ant barrier, take a few drops of peppermint oil on a cotton ball and wipe the potential nesting sites of odorous house ants to keep them away.

Vinegar Spray

Mix equal parts of water and vinegar (1:1) to prepare an ant-repellent spray. Pour the vinegar solution into the spray bottle and apply it directly at the ant trails, wall cracks, and other suspicious areas. The vinegar helps with removing the ant’s pheromone trails.

Related: Does Vinegar Kill Ants? | Effective Ant Control Guide

Water and Soap Spray

Soap and water solution is a harmless and effective way to kill ants and several other types of insects. You can prepare the soapy solution by mixing equal parts of liquid soap and water. Simply apply the spray and the ants will suffocate to death.

Ground Coffee

Ground coffee is another inexpensive home remedy for the odorous ant infestation. Sprinkle ground coffee around your garden and close to the walls of your house to prevent the entry of odorous house ants.

Cornstarch

Cornstarch is a safe way to kill ants without using toxic insecticides. Apply the cornstarch near the ant trails and shelters. Workers will take the powder back to their nest to feed the other ants. This process will eventually cause the death of the entire colony.

Natural Borax Baits | DIY Ant Bait

To prepare sugar-based ant bait, mix ground sugar and borax (3:1 ratio). Put the baits near cracks, ants’ trails, and at the entry points of odorous ants. The sugar will attract the odorous house ants and they will take the bait back to their nests. After they consume the bait, borax will kill the entire colony.

To prepare a honey borax bait, mix 1 tablespoon of honey and 1.5 tablespoons of borax. Apply the paste to a disposable container and place it near the ant trails.

Prepare a greasy ant bait by mixing 2 teaspoons of borax in 1 teaspoon of peanut butter. Put the bait on a lid or tape and place it near the ant trails in order to get rid of the entire odorous house ant colony.

Odorous House Ants Facts

• Odorous house ants produce a rotten coconut-like smell when they get squashed and that is why they are referred to as stinky ants, coconut ants, and odorous house ants.

• Multiple satellite-odorous house ants colonies are interlinked to one primary colony. The linked channels also help the ants to exchange food and workers.

• The male and female reproductive odorous house ants develop wings for a short time during the mating season which helps them during the breeding process.

• According to previous studies, the queen of odorous house ants can survive for over 2 months without water and food.

• The queen of odorous house ants has a high tolerance for hot and dry environments which means that she can ensure the survival of a colony even in harsh weather conditions.

List of Sources

PennState College of Agricultural Sciences (2020). Odorous House Ants, Insect Advice from Extension.

Davis, R. and Taylor, A. (2019). Odorous House Ants (Tapinoma sessile).

Michael F. (2018). Ant Control for Householders. Extension Entomologist, University of Kentucky

Buczkowski, G. and Richmond, D.S. (2012). The effect of urbanization on ant abundance and diversity: a temporal examination of factors affecting biodiversity. PloS one, 7(8), p.e41729.

Odorous House Ant Identification Resources, University of Nebraska – Lincoln