How To Get Rid of Carpenter Ants

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STEP 1) Investigate and Identify the Problem

When it comes to ants, there is no "one size fits all" treatment for all species and circumstances. In fact, what will work to prevent and control infestations of one species of ant may actually encourage infestation when applied to other species. When inspecting for Carpenter Ant infestations, look for the following indicators:

Physical Appearance - Carpenter Ants are often called the "Big Black Ant" although some subspecies may be reddish-brown in color. Size may range from ¼ inch to ¾ inch. The ants you see may be either wingless workers or winged reproductive ants from the colony.

Frass - As carpenter ants bore their nests, they leave behind several piles of fibrous, finely shredded sawdust-like material called "frass" which is made up of wood shavings, soil, and insect parts.

Sounds - If you identify a potential nest site, try tapping against it with a screwdriver with your ear placed to the wall. Alarmed Carpenter Ants will make a faint clicking or rustling sound.

Wood Damage- Look for smooth, clean galleries and small windows or slit-like openings in infested wood as a sign of nesting. These slits acts as "garbage chutes" used to dispose of frass and other materials.

Trails - Carpenter ants form tight, closely associated trails that can be traced to the nesting area. Look for trails along carpet edges, door frames, fence tops, etc.

Carpenter Ants vs. Termites
Both Carpenter Ants and Termites cause wood damage. Find out how to determine the difference and identify which pest you have.

STEP 2) Locate the Carpenter Ant Nest or Colony

  1. Know the favorite nesting sites of Carpenter Ants. These include structural wood, wall voids, attic areas, insulation (foam or fiberglass), hollow doors, window/door casings, cabinet voids, and hollow beams.Carpenter ants also prefer wood that is slightly moist so don't leave out areas near sinks, tubs, or dishwashers.

  2. Keep an eye out for ant trails. A trail is the course of travel ants take to and from the nest. If you are always seeing these ants in the same area or location, that location is likely part of a trail.

  3. Place a piece of tape sticky side down at several locations along the trail or in the pathway of several different trails. Place a dab of honey or peanut butter on top of the tape.

  4. Keep a night watch. This may take time and patience. Wait for one of the Carpenter Ants to take the bait, and then carefully follow its trail as far as you can. Hopefully, it will lead you to its nest.

  5. Remember the signs of carpenter ant nesting as discussed in step 1. These include the presence of frass, hollowed out wood galleries, and slit-like openings in the wood.

STEP 3) Modify Your Home Environment

An effective control program for carpenter ants must include good sanitation and other modifications to your home environment. The following will discourage the entry and survival of carpenter ants:

Cut back tree limbs within 5 feet of your roof. Carpenter ants often enter homes and other structures from above by dropping from tree limbs.

Remove firewood from the sides of your home and keep piles elevated so they do not touch the soil directly.
Use caulk to seal any cracks along foundations, siding, and windows and doors.

Install mesh screens over attic and crawl space vents.

Fix plumbing leaks, properly adjust sprinkler heads, and reroute air conditioner drains as necessary to eliminate sources of water carpenter ants need to survive.

Keep your home vacuumed. Do not leave food or crumbs lying around. Store bulk food and food storage properly in airtight containers with tight-fitting lids.

STEP 4) Choosing Methods of Pesticide Application

There are four basic control methods of pesticide application for getting rid of carpenter ants, based on the known or suspected location of the colony. Most often a combination of these methods will be your most effective tool to get rid of carpenter ants, rather than using one method alone.

Outside Perimeter Treatments
:  If you suspect that carpenter ants are entering your home from an outside location to find food, you will need to treat the perimeter of your home with a residual spray such as Suspend SC, Talstar, or Cynoff WP. Used alone, these products will not eliminate ants inside voids and walls, but they will help prevent future entry by additional ants while you focus on eliminating those that have already found their way inside.

Wall Void Treatments:  Delta Dust or Drione Dust are both excellent choices for void treatments. You will need to use a hand duster or electric duster to make sure the dust is evenly distributed. If the dust is not evenly distributed the ants will be able to detect it and will avoid it. When applied properly however, carpenter ants will not detect the dust and walk through it. Then, when they return to the colony and groom themselves and each other, the poison will spread throughout the colony.  Read more on how to apply a dust treatment.

Spot Treatments of Infested Wood:  If you know exactly where a carpenter ant colony is located, a localized spot treatment with Bora-Care will quickly eliminate the infestation. Inuject Bora-Care directly into infested galleries. Once the colony has been treated, treat the surrounding area and all wood susceptible to attack to reduce the possibility of colony relocation.  Confined areas can be treated using a foaming device . You can find detailed foaming instructions on the label of the pesticide to be used, or included with the foaming device.

Baiting: Baiting is the most effective method for controlling carpenter ants. Never treat an area with spray and bait at the same time. The fastest way to destroy the effectiveness of bait is to contaminate it with another pesticide. You can use sprays and dusts while baiting, just be sure to keep the baits in separate areas.
Read more on Carpenter Ant Baiting tips and techniques

**Don't Just Spray Something!

You will be able to get rid of Carpenter Ants more effectively if you can locate where they are coming from. You may be tempted to skip this step and simply "spray something" on the visible ants or coat your baseboards with repellent poison. However, doing this will only make the infestation worse! Here's why:  Contact sprays only kill exposed worker ants, with no effect on the queen. Since ants have a natural tendency to survive, when large numbers of worker ants begin to die the instinct of the queen will be to protect herself and her colony by increasing their numbers-in other words, laying more eggs. And many times these new workers will far outnumber the originals, sometimes doubling the colony size.

Pesticide sprays tend to be repellent, meaning the ants sense the poisonous chemical and simply avoid them by making new trails. When pesticides are sprayed too close to the colony, the queens and workers may simply pack up and move the colony-eggs and all-to a different location. Sometimes this even results in "satelliting", where the colony splits into two and establishes two new nesting sites instead of one.

Carpenter Ant Kits

Carpenter Ant Kit #1
Carpenter Ant Kit #2

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