Carpenter ants or wood ants? Similar to termites, they damage wood. Unlike termites, carpenter ants do not eat wood for food. They bore and tunnel their way into it to establish a nest. Spraying pesticides can make them many times worse. Learn how to control and get rid of Carpenter ants for good!
Carpenter ants in North America usually involve 3 main species. The Florida Carpenter Ant usually referred to as the red and black carpenter ant, the Camponotus Modoc (western US) and Camponotus Pennsylvanicus (eastern US) usually referred to as the big black carpenter ants .
Since the Florida Carpenter Ant, Camponotus Modoc and Pennsylvanicus have similar nesting patterns and feeding patterns, their habits and control methods are similar. Some carpenter ant species may have different diets and habits depending on the geographical region in which they are located, time of year, and certain other factors.
Big Black Carpenter Ants (C. Pennsylvanicus) colonies area usually of moderate size, some containing over 3,000 workers (up to 10 -15,000 including satellite nests). It may take 3 to 6 years for a nest this size to develop.
The Western Carpenter Ant (C. Modoc) mature colony contains about 10,000 -20,000 workers, with large colonies having up to 100,000 workers. Developmental time (egg to adult) for workers takes at about 60 days.
Worker ants of all three species have different sizes (polymorphism), with majors, minors and intermediates present. The average size of worker carpenter ants can be anywhere from 3/8 inch to more than 1/2″ long. Winged reproductive queens can be close to 3/4″ long with wings present.
Florida Carpenter Ants
Size: 3/8 ” to 1/2 ”
Color: red and black
Carpenter Ant Workers
Size: 3/8″ – 1/2″
Color: red, brown, black
Carpenter Ant Worker
Size: 3/8″ to 1/2″
They Don’t Eat Wood
Most people think carpenter ants eat wood just like termites. They do not eat wood at all. Carpenter ants “excavate” wood to make their nest and establish their colony. But they feed on plant juices, honeydew, aphids and other sweet sugary insects for their food source.
Aphids are Carpenter ants #1 choice of food. They take care of Aphids to harvest their honeydew. These ants will care for, groom, raise and nurture aphids within their colony in special “aphid” chambers. Aphids secret honeydew which is the Carpenter ants favorite food. It’s nature’s way of allowing ants and aphids to live in harmony with each other. What happens when the Aphids stop secreting honeydew? They become carpenter ant food!
It has often been thought that in order to get rid of Carpenter ants, all you have to do is to get rid of the Aphids. This is not true. Carpenter ants will feed on many plant juices and other insects. They require not only a carbohydrate food source (honeydew), but also protein. Carpenter ants get their protein from the insects and plants they feed on. As any vegan would tell you, their is a lot of protein in plants.
Getting rid of Aphids by spraying plants, shrubs and trees can help eliminate Carpenter ants, but can also complicate control strategies since the worker ants will also be killed. An overall spray method to control Carpenter ants is seldom recommended. In most cases, spraying everything outdoors with a liquid pesticide or doing what is known as an “outside wash” results in the Queens laying eggs and reproducing faster.
Carpenter ants will also “split” or bud their colonies into several new colonies for survival.
Unless you know exactly where the nest is and can kill all of the ants directly, without any getting away, baiting is the best control measure short term and long term to get rid of and control Carpenter ants.
Carpenter ants can be considered wood destroying pests because of their ability to cause damage to wood. The amount of damage carpenter ants cause is usually far less in comparison to that of subterranean termites. However, if carpenter ant nests are left untreated and undisturbed, the shear numbers of ants can be enormous and the resulting damage caused by “excavating” of wood to increase the nest size can be substantial.
Carpenter ants have a habit of cleaning and polishing the galleries in the wood. The galleries are smooth in appearance and do not resemble the rough jagged appearance of subterranean termite galleries.
During the mining or excavation phase of nest building, Carpenter ants make small “kick-out holes” out of which all the trash and debris accumulated within the nest are tossed out. These tossings are called “frass”. The frass which consist primarily of wood chips, insect particles, dead ants, etc, often form small scattered piles.
If frass of any kind is found, it should be carefully inspected with a magnifying glass to determine that it is carpenter ant frass and not the frass of drywood termites.
Drywood termites (only found in southern coastal regions) will toss their frass out of small kick out holes too. The difference is that drywood termite frass is made up of their excrement and does not contain any insect particles, wood shavings, etc. Drywood termite frass only contains fecal pellets which if viewed under a magnifying glass resemble a small football with 6 concave sides.
RELATED: Drywood Termite Identification
If you see live Carpenter ants or find their frass, then action needs to begin immediately. If you let the carpenter ants continue to populate and the nest to grow, then control becomes much more difficult and in some severe cases results in multiple nests with control difficult to achieve.
How To Kill Carpenter Ants
Before any efforts are made to kill carpenter ants, a program or strategy needs to be implemented. Do not simply spray “something” on worker carpenter ants without considering the consequences. Spraying an “over the counter poison” on the ants without any strategy will greatly complicate your control and make the infestation much worse.
Pesticide Sprays Only Kill Exposed Worker Ants
Spraying pesticides on ants you see will have no effect on the queens or the colony. The strategy behind spraying is to kill the worker ants. The problem is that most pesticides require frequent re-applications over a long period of time (months) to kill the majority of worker ants. During this time the queens will go into a reproductive cycle and begin egg laying and colony splitting.
The resulting large numbers of worker ants dying results in rapid egg laying and reproduction. The queens will lay more eggs, and since the queens will not be killed by sprays, the number of eggs will grow and multiply and eventually outnumber the numbers of the original workers. That means your carpenter ant colony is now several times larger – all because the ants have a “natural tendency to survive”.
Carpenter ants will also move and split their colonies to get away from pesticide sprays. Since all over the counter pesticides are “repellent” the ants simply move away from them to avoid them.
Pesticides Are Repellent And Will Cause Rapid Egg Laying
Most chemical pesticide sprays tend to be very repellent to the ants. Chemical or pesticide repellency simply means that the ants can sense the presence of pesticides and will avoid them. The worker ants will simply avoid the chemical you sprayed and travel or trail around it. In some cases, ants and termites have been known to line their trails with the bodies of dead workers making them a “bridge” so that they can crawl over them to avoid the pesticide.
If pesticides are sprayed too close to the nest, the queens will instruct the workers to pick up the eggs and move the nest farther away. They will also instruct the workers to divide or “split” into several new nests. This splitting or dividing of the carpenter ant nest is called “satelliting” or “budding”.
After the new nests are established, the new queens begin to lay more eggs and the Carpenter ant colony has multiplied. Instead of a single nest there can be several nests to deal with, making control much more difficult.
Using Non-Repellent Pesticides Doesn’t Work
Using a non-repellent pesticide, one that the ants cannot detect may seem like the answer. Phantom Insecticide is the only spray product that comes close to being non-repellent. However, it’s effects on Carpenter ants have never proven to be consistent. That’s because Carpenter ants don’t forage indoors for food sources. The only ants that could be effected are the scouts. Worker ants will remain in the nest and/or outdoors foraging for food.
Termidor Insecticide is only for indoor use inside of walls and voids. It can also be used as outdoor barrier spray on the foundation, but is not labeled for use on eaves, attics, soffits and places where Carpenter ants would normally be found. It’s use on Carpenter ants outdoors is very minimal.
Termidor Foam can be used in a direct nest treatment. But you have to know exactly where the nest is and treat it without the worker ants getting away. If you are not successful in killing the entire nest, then rapid egg laying and reproduction will result.
Non-repellent dust pesticides such as Timbor Dust can also be used indoors. Timbor requires a very thorough dusting of every wall, void, crack and crevice to have any effects. This is usually done by removing wall switch plates, electrical and plumbing covers, etc. It can also be mixed with water and sprayed like a liquid pesticide. When the water evaporates it leaves a thin film dust on surfaces sprayed. Timbor cannot be used outdoors and will kill plants.
Carpenter ants will contact Timbor by crawling through it. Timbor then has to be ingested by ants somehow. Unless it is used as a liquid bait and eaten by them, it is not fully understood how Timbor effects ants since it has to be eaten and does not kill by contact.
As with almost all pesticide sprays and dusts, Timbors use has not proven consistent in controlling Carpenter ants, and the labor required to apply it is substantial.
Use Slow Acting Liquid Baits
Long term control of Carpenter ants can only be achieved with baits. Many Carpenter ant baits are on the professional market. Their success in controlling them is usually directly attributed to where and how often they are applied.
Maxforce Carpenter Ant Bait Gel can be used successfully if you know where the nest is located. The product is a bait gel and dries within a few days. For this reason, it has to be reapplied every few days to remain effective. Multiple applications are necessary in most cases.
Slow acting liquid baits ensure that the workers have time to return to the colony with the “toxicant” and distribute it.
Some baits such as Advance Carpenter Ant Bait and Maxforce Carpenter Ant Bait Gel can provide some control, but need to be reapplied every few days. The trick to getting these baits or any bait to work is keep a constant steady supply present.
Most baits for Carpenter ants go rancid within a few days. The only way to keep most baits available is to continually apply them.
The only bait system that has proved easy to use and does not need continual reapplication is the KM Ant Pro liquid bait dispenser and Greenway Liquid Ant Bait. This is an outdoor baiting system that provides the ants with a constant food source. It also kills the workers slow enough to not “alarm” them or cause any disruption.
This combination has proved the most beneficial in University and Government funded studies. It is also used in National Parks, by major growers and in countries around the World.
Kill Them Outdoors
Carpenter ants need a damp environment or some water source for survival. They must also be close to a reliable food source. Carpenter Ants love sweet foods such as citrus juices and honeydew, but will also eat almost anything that is insect, plant or animal related.
As “scout” Carpenter ants forage for food outdoors, they leave “pheromone” trails to instruct the worker ants where to feed. This pheromone trail is instrumental in Carpenter ant control. The pheromone trails will lead directly to the food sources.
Spraying chemicals can disrupt these pheromone trails, cause the ants to scatter, and encourage rapid egg laying and reproduction.
Most pesticide sprays only kill the worker ants and will not penetrate the core of the colony. Additionally, when using sprays you may actually stress out the colony which can cause the Queens to lay more eggs for colony preservation. The colonies will then split or “bud” into several new colonies. This is called ant colony “budding”.
This is why slow acting baits always provide the best control of Carpenter ants. But in most cases, they have to be applied outdoors to be accepted.
Indoor baiting is marginally effective. As mentioned, Carpenter ants forage outdoors for food sources. In order for baits to work, they have to be accepted by Carpenter ants and utilized as a secondary food source, then as a primary food source as their other food sources become depleted.
This is why regular applications of baits are key to Carpenter ant control. Baits have to be available at all times for them. A single application of a granular or gel bait could be worthless due to it becoming rancid before the ants find it. Granular and gel based Carpenter ant baits are food based and need continual re-application.
Repeated applications are the norm with ALL baits except the KM Ant Pro liquid bait dispenser. It keeps the liquid bait protected and prevents evaporation. This “patented” dispenser is the one of its kind that offers uninterrupted feeding for up to 90 days.
Related: KM Ant Pro Liquid Bait System
The KM Ant Pro liquid bait dispenser provides an alternative food source containing a honey and boron based bait matrix. This combination provides Carpenter ants with a food source that is slow acting enough to kill the worker ants over a 60-90 day period. Slow enough that the colony does not get disturbed or begins re-population and egg laying efforts.
Once the worker ants have died, the colony cannot feed itself and begins to slowly starve. Over a period of several months, 90%+ control has been obtained in areas where pesticide sprays provided little to no control.
The KM Ant Pro system will kill outside foraging ants preventing them from getting indoors, and also create a protective barrier that stops off-premise ants. It works for almost all species of invasive aggressive ants and works well to kill Carpenter ants.
Don’t Try To Kill Them Indoors
Indoor treatment for Carpenter ants begins outdoors. Unless the outdoor invading ants are stopped, they will continually invade and indoor control efforts of any kind will be useless. No indoor treatment is 100% effective, because Carpenter ants live and forage for food primarily outdoors.
Carpenter ants live in nests excavated in wood, which is usually hidden inside a wall or eave. If you know exactly where the nest is located there are a few products that can be used to kill them. But you can’t let any get away!
Indoor baiting will have little to no effect on a large Carpenter ant colony.
Treatment of wall voids with BorActin Dust can give limited control, although it usually takes several weeks or months to see results. Repeated applications may also be necessary to “dust” areas where ants are seen or found.
Indoor baiting with Maxforce Carpenter Ant Bait Gel can also give results although colony control is usually not achieved.
If you absolutely must do something indoors to kill carpenter ants, then Termidor Foam and Timbor will give the best results. As mentioned previously, these products only work if you know exactly where the nest is located. If you don’t know where the nest is located, then any indoor efforts can be useless.
Make It Easy
Controlling and getting rid of Carpenter ants can be a futile experience if the correct methods are not used. There are no magic sprays or bombs that will kill an active hidden Carpenter ant nest located inside a hidden wall or void.
Carpenter ants don’t just mysteriously appear with a “fully populated” colony. It’s usually a process where a single queen was embedded into a nest and egg laying began. Colony development takes time, years in some cases. Overnight or instant cures are not available. It’s a game of patience unless you are really lucky at finding the nest.
In most cases, if you stick to an outdoor baiting plan, control of Carpenter ants will come – even if you are finding them indoors.
It’s very simply a process of letting them find and accept your bait as their secondary food source, and ultimately their primary food source. When this is achieved, control of indoor ant colonies as well as outdoor colonies is much easier – and longer term. Outdoor baits can then be used to “ward off” invading ants and help prevent future infestations.
Using Carpenter ant baits takes time to work, but don’t cause the Queens to begin rapid egg laying and reproduction. Sometimes, as is the case the KM Ant Pro Liquid Bait System, this can be several weeks to a few months. But once they transition to feeding, control will come quickly.
If its winter and using outdoor baits isn’t realistic, then waiting until spring arrives is usually the best option. Indoor treatments may seem like a quick fix, but almost always result in problems down the road that were caused by “human error” or impatience.
Carpenter ants have been around for over 200 million years. If you find them wandering around somewhere, don’t make the mistake of thinking a $5.00 can of bug spray will solve the problem. As with most things, a strategic calculated approach works best. If you have taken the time to read this article, then you are half way there.