Carpenter Ants

Overview

Carpenter ants, Camponotus spp. are among the largest ant species in North America. Although they do not eat wood materials, they still can cause noticeable damage to wooden structures by nesting in buildings. Like many pests, they are a nuisance by their presence, especially when found indoors wandering in kitchens, bathrooms, and pantries. They are also capable of contaminating and stealing human's food. While there are as many as 50 species of carpenter ants in the US, the most commonly encountered species in homes is the black carpenter ant, Camponotus pennsylvanicus. Other carpenter ant species may be more reddish-brown in color. It is important to solve carpenter ant problems as early as possible before they turn out to be costly and difficult to manage, especially when they excavate their satellite nests inside walls in confined spaces.

Facts

• Carpenter ants excavate into the wood to nest using the softest parts as channels and leaving the hard parts intact as a wall to support the gallery.
• Chambers made by carpenter ants are smooth and clean, giving them an almost sandpapered appearance. The worker ants carefully deposit any debris, such as shredded wood particles and dead insect parts outside the nest via a slit-like opening (kick-out hole). This smooth, clean form of the nest structure often appears as if it were done by carpenters, hence the name.
• The queen uses the sperm deposited at the mating flight time for all the eggs she will fertilize in her lifetime.
• The queen ant secretes pheromones (chemical signals) that regulate the behavior and some biological aspects of the other members of the colony. When the queen dies, the colony eventually dies later.
• Carpenter ants can communicate by touch (tapping the antennas), smell (leaving pheromone trails, emitting formic acid in danger, etc) or sound (drumming their heads on the floor of their chambers).
• Workers must help the new adults emerge from the pupa case; otherwise they can't emerge.
• At any given time, only 1-3% of the worker ants are outside the nest foraging for food and water.
• In harsh conditions when food is not available, worker ants can live up to six months without food.

Identification

• Carpenter ants are black or red and black in color with an evenly rounded thorax when viewed from the side.
• The waist contains one node (petiole: a stalk or peduncle, as that connecting the abdomen and thorax in ants and wasps).
• As there are several various species of carpenter ants present in Minnesota, it can be difficult to identify carpenter ants by their size alone. Additionally, carpenter ant workers are polymorphic, which means within the same species, worker ants are not all the same size. Usually the worker carpenter ants are about 3/8" - 5/8" long. Though, the queen is larger and can reach up to one inch in length.
• Another distinguished characteristic of carpenter ant species is the presence of a border of tiny hair at the end of their abdomen.
• Carpenter ants are social insects live inside a colony. Each colony is made up of different cast members: one egg-laying queen, drones (male reproductives) and workers (major and minor).
• Carpenter ants construct two types of colonies. The main colony (sometime called "parent colony"), which contain a queen, young larvae and workers. The satellite colonies, which nest inside the structure and contain pupae, mature larvae, winged male and female reproductives (swarmers) and workers.
• Carpenter ant workers make a distinctive clicking sound (like crinkling cellophane) inside the wall.

Biology

• Carpenter ants follow a complete metamorphosis, in which they go through four separate developmental stages (egg, larva, pupa and adult) during their life cycle. Homeowners sometimes mistakenly referrer to the pupa stage as "eggs" because they see the ants carry them from the parent nest to the satellite nests.
• Each colony has only one wingless egg-laying queen. This queen normally lives for over 20 years in the parent/main nest outside a structure, and lay over 70,000 eggs during its life span. Carpenter ant workers live up to seven years, and are responsible for collecting food and excavating nests. They also feed, clean, care for, defend and expand the colony.
• Carpenter ants expand to form satellite colonies, where a number of workers depart to tunnel galleries in wood to nest inside a structure.
• Carpenter ant workers are attracted to the home by the presence of "weakened wood" usually as a result of water damage in the past.
• Several satellite nests (up to ten) can be associated and connected with a single parent colony via pheromone trails. These nests can be located as far as 300 feet away from the main colony.
• Ants from these satellite nests are what the homeowner will see inside their home.
• A main colony takes two or more years to reach maturity with over 3,000 workers.
• A queen of a mature colony will produce male and female reproductives. These will be transported into satellite nests in a pupa stage usually during late summer.
• The winged male and female reproductives emerge from satellite nests and swarm during the spring.
• After mating, males die soon and newly fertilized females lose their wings, and then each queen begins to establish a new colony in a small cavity in wood, under bark, in rotted stump, etc.
• Each new queen lays about 15-20 eggs over the next 15-20 days.
• Carpenter ant eggs are always kept in the main colony outside where the moisture level is higher than the structure. Eggs usually hatch in 24 days, and newly emerged larvae go through four developmental instars within approximately 21 days. The queen rears the first brood from food reserves that are stored in her body. Therefore, workers from the first brood are smaller in size comparing to workers from next generation. However, further broods, will be fed and cared for by worker ants
• Fully mature larvae pupate in cocoons for 21 days. Initially, the queen helps the first generation workers to emerge from their cocoons. But afterward, workers will take up this responsibility for the next generation.
• The life cycle of carpenter ants last about 66 days from egg to adult at 70 to 90°F.

Habits

• Habitats- As their common name may indicate, carpenter ants are capable of excavating wood materials to build a nest. They prefer moist damp wood, but in heavy infestations, they may tunnel into solid wood. Primarily, the infestation begins in pre-existing, rotted hole or void of wood, and then expands into both decaying and intact adjacent wood around original holes. At homes, carpenter ants habitually build their satellite nests around rotted windowsills or doorframes, around sinks or other moist, poorly drained places near kitchens and bathrooms. However, satellite nests do not need as much moisture as the main nest (where eggs are found) and can be found throughout a home, even in dry areas such as hollow doors and insulation. Parent nests are always built outdoors and located in decaying or rotten wood such as in a live or dead tree, stump, woodpile, or landscaping materials. Carpenter ants leave behind "frass" as a cone-shaped pile accumulating of fibrous, finely shredded, coarse sawdust materials. This frass may contain wood fragments, soil, and insect parts. Examining the kick out hole will lead to smooth and sandpapered galleries (nest). During the warm sunny days of the winter months, carpenter ants may become active and be seen in the house. In this situation, it is important to find out where these ants are coming from. If carpenter ants are coming out of firewood during winter, they will not build a new nest inside the house. Otherwise, if they are seen inside the home during the winter, and not associated with firewood, it definitely means you have a satellite nest inside the home since the colonies outside the home are dormant during the winter.

• Feeding habits- Carpenter ant workers maintain trails between the parent and satellite colonies. Depending on the temperature, carpenter ants are generally active from April to mid-October. Worker ants are most active after sunset, and remain working throughout the night until sunrise. However, it is not unusual to see them foraging on their trails during the day. Foregoer workers carry food back to the nest and feed it to the queen, larvae and other members in the nest. They prefer sweet, especially honeydew, but they can feed on a different variety of food materials, such as dead insects, meat, grease and fat. Interestingly, carpenter ants change their feeding preference throughout the season. For example, they prefer protein-based food materials during the spring to accommodate larval development needs of protein. During the summer when adult workers are active, a switch is made to carbohydrates (e.g., honeydew) as an energy source for the hard working workers. This crucial fact is important in bait selection process throughout the ant season. The presence of an occasional ant infestation does not necessary mean the presence of a nest in your home. When food is not abundant, forager ants may enter the house searching for food within 100 yards away from the nest. However, the continuous presence of ants inside the house, especially in a big number is a better indication of nesting possibility inside the indoor premises.
• Aggressive behavior- Carpenter ants are not aggressive, but they can deliver non-poisonous bites when handled.

Treatment

It is common to see workers of carpenter ants entering buildings, especially those located within 300 feet from their parent nest looking for food. These infestations are more experienced by people, mainly as the weather warms in the spring and cools in the fall. In order to successfully prevent or manage carpenter ant infestations, the Adam's carpenter ant program is developed to contain two pesticide treatments. The first treatment is normally applied during the spring, while the second treatment is scheduled in the fall. These applications are designed to place an insecticide barrier, approximately one foot up the foundation and one foot out from the foundation wall. Additionally, applications of crack, crevice and spot treatments around any other ant entry points, such as windows, doors, vents, wires, pipes, attached fencing, tree limbs, etc, as well as along porches or patios and flower boxes. The purpose of the barrier treatment is to intercept any ant that is attempting to enter or leave your home. However, if ant's nests or trails are found, they can be treated directly with an insecticide. The treatment of carpenter ants is usually performed with "non-repellent" insecticides that are not detectable by the ants and are transferred to other individuals as they feed and groom each other. During this process, the product is shared throughout the colonies resulting in the elimination of the entire colony. Interior treatments are generally applied to moisture areas, such as bathrooms, kitchens, laundry areas, furnace rooms, and doorways, where ants may be foraging for food and water. The treatment material is effective in controlling ants for several months and eliminates the need for costly monthly/bi-monthly treatments with traditional insecticides. Therefore, and as above-mentioned, Adam's recommends that the treatment of carpenter ants be performed twice annually, and all structures treated are put under a renewable annual guarantee. This will solve the carpenter ant problems and reduce the costly unnecessary repeated treatments.

When a carpenter ant activity is frequently encountered in a home. The Adam's pest management professional (PMP) will inspect the house to determine the areas of highest potential for ant nesting activity and apply a directed treatment to that area to quickly eliminate any satellite nests. The PMP will also determine if there are any current or past water leaks or any obvious water damaged areas, such as around window ledges, door frames, thresholds, leaky roofs, sky lights, patio doors, decks (ledger board area), porch additions (where roof meets house), water stained wood, leaky plumbing, bathtub problems, or windows which develop condensation or frost in the winter that may need maintenance by the homeowner to reduce the likelihood of future infestations. The PMP will also search for the presence of coarse sawdust material with insect parts as a major indicator of carpenter ant activity. It is not necessary to drill large and possibly damaging holes into walls or windows in your home to solve your ant problem.

This because of the fact that ants living inside the structure of the home will definitely forage inside and outside the home and will pass through the treated areas and receive a lethal dose of insecticide. However, it is important to remember that when non-repellent insecticides are used, the nature of this kind of pesticides allows ants to take the poison active ingredients back to their nest; therefore, ants may continue to be seen after treatment until the entire colonies die. If baits methods are used, ants will be eliminated within the two to three weeks following the treatment.

To successfully manage carpenter ants, preventive and protective measures against these pests are also crucial. If there are any tree limbs touching the home Adam's recommends that the homeowner contact a professional tree trimming company to correct that problem so that ants cannot enter the home directly from the tree and bypass the treatment barrier around the home. Shrubs next to the home should also be trimmed back from touching the structure. Any dead stumps around the home should also be removed.

In conclusion, carpenter ant treatment programs and pricing plans vary widely from company to company, as does the pricing. Ant infestations are a potentially serious problem but the structural integrity of your home is not threatened so don't be rushed into a treatment program which may cost you hundreds of dollars. Adam's has been treating homes for over 30 years and has developed a treatment program that is very effective and affordable to homeowners.

Frequently Asked Questions

Q: Do you need to drill holes in my walls?

A: It is usually NOT necessary to drill holes in order to treat for carpenter ants. The ants themselves need to have a means of getting in and out of the void areas, so we inspect and treat all those possible entry/exit points. We may remove electrical outlet/switch covers, which gives us access to common travel routes of these ants. DRILLING HOLES IN EXTERIOR WALLS IS NOT EFFECTIVE because the insulation in the walls will usually prevent the insecticidal dust from freely flowing throughout the complete void area. Consumers should be able to expect that pest control technicians will stop the damage being created by carpenter ants, not create more problems with unsightly holes in their walls and windows.

Q: Do carpenter ants bite?

A: Although it is possible, it is very rare that they will bite humans. You might have to lie down in a hollow log infested with ants in order to get bitten. Anyhow, carpenter ants will bite and spray formic acid into the wound in defense and on contact. Usually, their bits feel like a pinch and do not need a treatment unless the skin is broken and the bitten person is hypersensitive or allergic to the spray formic acid.

Q: Do we have to leave the house when you do a treatment?

A: It is not required that you leave. However, if you feel more comfortable, you can leave for about 2 - 4 hours until the application has completely dried. If you stay in the house, homeowners, children, and pets, should not be in the area while it is being treated. Customers should advise the technician of any health related issues present in the household so that the technician can take any appropriate precautions.

Q: Is the pesticide treatment harmful to pets?

A: The only pets that seem to be sensitive to minor changes in their environment are birds and fish. If you have birds, you may want to move it to another location. During the treatment process all pets must be moved to areas of the home, which will not be treated and kept there until the treatment has dried. Once the treatment is dry pets can resume their normal activities.

Q: Is my house going to be damaged by carpenter ants?
A: Unlike termites, carpenter ants do not eat the wood in your home; they bore into it to make their galleries. Although carpenter ants do cause damage and should be of concern, they're nests grow at a relatively slow rate. Also, remember that the nests are usually bored into wood that is already damaged due to water or dry rot, therefore you should be concerned about damage do to water leaks and seek to get that corrected. The presence or rotted wood does not necessarily mean you have carpenter ants, however, the presence of carpenter ants may indicate a rotted wood issue in the structure. Anyway, the extent of carpenter ant damage depends on the number of satellite nests found inside you house, as well as the period of the infestation (how long they have been tunneling inside the wall). Therefore, it is advisable to act fast when you see carpenter ants before they become a real problem in your home.