Carpenter Ants
Carpenter ants are social insects that live in colonies, primarily in wood. They hollow out wood to build their nests. Carpenter ants are an excellent indicator of moisture problems in a home or structure. Carpenter ants are attracted to damp wood, wooded or heavily foliaged areas, stumps, and homes. Carpenter ants destroy wood. They do not know the difference in a dead tree stump or the wood used to build your home. They can cost a homeowner thousands of dollars in damages if not identified and controlled.
Identification
Carpenter ants are among the largest ants in the United States. Adults vary in length from about 1 /4 inch up to 7 /16 inch. Each colony has one functional, wingless queen, 9 /16 inch long. Their color ranges from a red-brown, to a solid black, or red-brown and black.
The ants develop through several stages in their metamorphosis: egg, larva, pupa and adult. All stages can be found in a colony, but identification is made from the adults, which are the familiar ant-like insects with 6 legs, 3 distinct body regions with a constricted waist, and prominent elbowed antennae. Carpenter ants have only one segment or node between their thorax and abdomen, a circle of hairs at the tip of their abdomen, and an evenly rounded thorax when viewed from the side. Some may have wings.
Winged carpenter ants resemble winged termites and, in Texas, it is not uncommon for both of these important wood-destroying insects to swarm at about the same time. It is vital that they be identified accurately, because control measures differ greatly for the two insect groups. See “Termites” to help you identify the differences between the two.
Ants look like ants with three body parts, where as termites only have two body parts.
Biology
The colony remains small during the first year, but in later years it grows rapidly, up to a maxi-mum of 2,000 to 3,000 ants. It usually takes 3 to 6 years for a colony to reach this size, at which time winged reproductives are produced.
A mature colony produces 200 to 400 winged individuals each year. Production drains colony resources, keeping ant numbers down. Winged reproductives usually swarm in spring and early summer. Right after a rain or a shower and the sun comes out is a prime time to see their movement around the home.
The main purpose of carpenter ants in the environment is to break down dead wood and put it back in the ground so new growth can take place.
Areas Infested
Carpenter ants normally build their nests in hollow trees, logs, posts, landscaping timbers, voids in the ground and wood used in homes and other structures. Unlike termites, they do not feed on wood but merely use it as a place in which to build a nest. They prefer moist or partially decayed wood, frequently entering existing cavities or void areas through cracks and crevices. Door frames, window frames and moisture/pipe areas are a prime place for them to nest.
Occupied galleries are kept immaculate. Shredded wood fragments from the excavations are carried from the nest and deposited out exit holes or cracks and crevices. These piles are usually, but not always, found around window sills, door frames, or under doors. The piles may also contain inedible parts of insects from their diet, dirt, and dead ant bodies from the colony. The piles are often referred to as frass. Piles might not always be visible, because ants may dispose of it in hollow parts of trees, void areas in structures, or unused galleries in the nest.
They usually nest in wood that is very moist or previously damaged by water or termites. Typical locations include.
- Wood rot from plugged drain gutters, damaged flashing, wood shingle roofs, poorly fitted or damaged siding, improper pitch of porch floors, between the roof and ceiling of flat deck porches, hollow porch posts and columns, leaking door and window frames and leaks around fireplaces;
- Areas around plumbing in kitchens and bathrooms where water leaks have occurred, soaking the surrounding wood;
- Wood in contact with soil, such as porch supports, siding and stair risers;
- Wood in areas of poor ventilation or condensation such as cellars, crawl spaces, attics or under porches;
- Stumps, wood piles, Debris in gutters or around the home.
- Around bathtubs or hot tubs;
- Hollow wooden doors, hollow ceiling beams, voids around the shower.
- Sill plates and floor joists;
- Voids under attic insulation or under insulation in crawl spaces; and
- Voids above windows, doors and bay windows.
Control
Inspection
The Inspection is the most important part of controlling any insect population. Carpenter ants are no exception. It’s not uncommon to see carpenter ants out and about around the eaves and perimeter of the home. These ants are usually foraging for food. These are easy to kill, but finding the colony and eliminating it is the only way to get rid of them completely.
Outside a structure, examine any tree stumps, roof edges, trim boards, facial boards, attached fences, foliage around the home, wooden columns, overhanging tree limbs, vines, power / cable and utility lines. In living trees, openings to a nest are usually in knotholes, scars, dead areas, or dead limbs. Carpenter ants may travel as far as 60 yards from their nesting place to a food source, and it is sometimes possible to follow foraging carpenter ants to find their nest.
Prevention
To greatly reduce the likelihood of carpenter ant infestations:
- Repair and replace all wood rot;
- Repair plumbing and roof leaks;
- Eliminate all wood siding and wood columns in contact with the ground;
- Provide good ventilation under the house and in the attic;
- Drain water away from the structure;
- Remove stumps, logs and wood debris near the house;
- Keep storage sheds away from the home;
- Keep firewood off the ground and away from the house;
- Trim back all tree limbs and all shrubbery from being in contact with the home (Tree limbs 4 ft. off & shrubbery 18 inches off the home);
- Keep exposed wood sealed and painted;
Insecticide Treatment
Carpenter ants are social insects, they groom, feed, and are constantly bumping into each other. Treatment of Carpenter Ants is best done using a baits or slow acting insecticides so that they can transfer it through out the colony. This increases the chance of killing out the colony and not just the few that come in contact with the insecticide. Liquid baits allow the ants to spread the chemical through out the colony. It allows the ants to travel unknowingly through treated areas and therefore spread the chemical to other ants and through the colony.
There are several ways we treat for carpenter ants;
- The use of a granular bait. This bait is put in active run ways, perimeter of the home/structure, or in the attic. Carpenter ants then take the bait back to the colony where the colony feeds on it.
- Fumigation can be used in controlled hollow voids such as hollow doors. A small hole is drilled in the door, fumigate is then injected into the door void.
- Slow kill liquid treatment. Liquid treatments can be made around the perimeter of the home or by drilling 1/8 inch holes in the mortar between bricks 4 ft. apart and injecting a liquid bait or slow kill insecticide in the void behind the bricks.
Carpenter ants are a wood destroying insect that needs to be identified and controlled as soon as possible.
