Technical Papers

NJ Ant Prevention

Sunday, November 4th, 2018 by Bill Cowley

New Jersey has more than its fair share of ant species that commonly infest homes. Ants are, by far, the most common nuisance insect faced by homeowners. All of us have had ant sightings in our homes, especially after a heavy rainfall when they are seeking higher ground. Foraging ants often wind their way to the kitchen where they can infest cabinets and contaminate food. Some infesting ants are aggressive and bite or sting. Others, like wood-boring carpenter ants and acrobat ants, can cause property damage. These ants excavate galleries in wood to build their nests. By and large, ants do not transmit diseases like cockroaches and rodents. The notable exception to this is the Pharoah ant. 

Ant infestations are especially challenging to resolve. This is due in large part because of their sheer numbers and their reproductive rates. What ants lack in size, they make up for in volume! Some ant colonies can grow to thousands upon thousands of members. Also, ants build well-hidden nest sites. It is rare, indeed, to find an out-in-the-open ant nest as we do with the nests of certain wasps and bees. Finally, many ants establish multiple satellite locations away from the “seed” nest, making the infestation more difficult to treat. 

To successfully resolve an ant infestation, the ant colony (or often colonies) must be eliminated along with its protected queens. Merely killing replaceable and expendable foraging worker ants does nothing to eliminate the infestation. And with ant colonies there is not a single queen. There can literally be hundreds of them!  

Homeowners often make matters worse with DIY treatments. Often, store-bought spray treatments expand the infestation by causing the colonies to relocate to even more inaccessible locations. Even worse, improper treatments can fragment a single colony into multiple colonies. With ant infestations, a professional pest control service has the most effective tools and resources to resolve ant infestations quickly and completely. 

Common New Jersey House Ants 

Carpenter Ants

New Jersey has eight carpenter ant species of different sizes and colors. The most common is the black carpenter ant. These ants, the largest ants found in New Jersey, can range from one-quarter inch to one-half-inch in length. They has a uniform dark shiny brown to black color. Carpenter ants take their name from what they do best:  chewing and tunneling through wood to create passageways (“galleries”) for building and expanding their nesting sites. Carpenter ants are often confused with termites when the winged reproductive are swarming. The two must be distinguished because each requires different methods of control.

Carpenter ants can cause significant damage. If left untreated year after year, their damage can become extensive. Also, once a carpenter ant colony is established, they do not simply “go away.” Homes with a carpenter ant infestation often have a water or moisture problem causing decaying or mold-infested wood. Carpenter ant nests are commonly found behind bathroom tiles, around tubs, sinks, showers, and dishwashers, and under roofing, in attic beams, and under subfloor insulation or in foam insulation.    

Pharoah Ants

Pharoah (also known as “sugar ants” because of their attraction to sweet foods and liquids) are yellow or light brown. They are miniscule – even by ant standards – with a length of about 1/16 of an inch. These ants are so small that they can be difficult to see and their size allows them to breach “closed” containers we believe to be sealed.  Pharoah ants can carry a variety of pathogens. They are a serious problem in hospitals and nursing homes where they are known to crawl into wounds, IV lines, and instrumentation, feeding on blood plasma and wound dressings.

Pharoah ants are sensitive to the cold, so in New Jersey, they live exclusively indoors. They commonly nesting in warm, humid areas nearby food and water. In homes, they are typically found either around kitchens or bathrooms, nesting under sinks near water pipes or in wall voids. They feed on a wide variety of foods including not only the usual sweet attractants like jellies, honey, and fruit juices. These ants will consume grease, dead insects, toothpaste, and even shoe polish.  

Pharoah ants colonies proliferate by “budding” -- a portion of the main colony splits off into multiple nest sites. In addition, its colonies can have hundreds of queens. To complicate the situation, their nests are not in plain sight. Because of their complex nesting behavior, DIY methods with Pharoah ants are generally ineffective.

Odorous House Ants

Odorous house ants (commonly known as “sweet ants”) are small ants -- about 1/8 of an inch long. They are dark brown in color. Their common name refers to the disagreeable “rotten coconut” odor that they emit when crushed. 

These ants commonly nest indoors in wall and floor voids. If only a few ants are found in the house, they are likely nesting outdoors and you’ve spotted a few foraging ants. However, if winged swarmers are found indoors or ant sightings are frequent, there is likely a nest inside the home. These ants forage for food along well-traveled trails feeding on dead insects, sweets, and meats.  

Odorous ants are known for swarming kitchen counters and floors. Their small size allows them to crawl into closed or sealed food containers making food contamination a problem. These ants expand their colonies by breaking into smaller colonies, so there are multiple nests with multiple queens.  Homeowners can find themselves with a heavy infestation in a short amount of time. Because odorous house ants, have massive populations, inaccessible nests, and termite-like swarming behavior, DIY methods are ineffective and usually make matters worse. 

Pavement Ants

Pavement ants are small ants about 1/8 of an inch long and are dark brown to black in color. They are so-named because they ofte nest under sidewalks and driveways. If you see piling dirt removed from the nest in a mound on top of the pavement, often located between sidewalk cracks, these are likely pavement ants. These ants also nest under stones, logs, boards, patio blocks and other items lying on top of the ground.

Pavement ants rarely nest indoors. Rather, they become a nuisance when they enter homes in search of food.  Entry points include doorways, cracks, and spaces under siding. The expansion joint along the lower edge of sliding glass doors is a common, but often overlooked, entry point.  

A pavement ant infestation can be quite serious if large numbers of these ants swarm into buildings built on concrete slabs. Because of the inaccessibility of their nests, eliminating these infestations is challenging and requires professional treatment. Winged pavement ant swarmers are seen in the spring and summer. They are often mistaken for termites. Correct identification is essential since the treatment for these insects differs.

Acrobat Ants

Acrobat ants are relatively small, only about one-eighth of an inch. The vary in color from light brown to black. They have a segmented body with a heart-shaped abdomen that is usually darker than the rest of its body. They feed on a variety of foods including other insects and sweets, and like many ants seek out aphid honeydew. Acrobat ants are so-named because of their unusual “contortion act” behavior when disturbed – they bend their abdomen over their body. 

These ants are aggressive and territorial. They have stingers, emit a foul odor when threatened and are quick to bite. Like all ants, the acrobat ants produce swarmers, winged, reproductive individuals that disperse in order to start new colonies. While swarmers are harmless, they are often the first indication of an infestation.

Acrobat ants are a wood-nesting ant. A tell-tale sign of wood-nesting insects, including acrobat ants and carpenter ants, is wood residue (“frass”) deposited nearby their entry holes. These ants are attracted soft, moist water-damaged wood and seldom tunnel into dry, sound wood. As such, these infestations usually indicate that there is damaged building materials in need of repair. Foam insulating board or sheathing behind siding and around skylights, wall voids, and hollow beams are also popular acrobat ants nesting locations. If nesting outdoors, they often find their way inside homes through cracks around windows and doors and other openings.  

Citronella Ants 

Citronella ants are about 3/8 of an inch long and are yellow to red-brown in color.  They are so-named for the citronella-like odor they emit when crushed. These ants feed on the excretion of aphids and mealybugs, which, in turn, feed on the roots of shrub. These ants live in subterranean colonies that typically have mounds of soil around the openings where excavated soil is deposited.  

On occasion, homeowners will find themselves with an inside swarm of citronella ants. Swarming typically occurs in mid- to late summer. Normally, these ants go unnoticed unless the swarmers enter through expansion cracks in slabs or around door or window openings. Although these intrusions are alarming, the ants do not reproduce within the home. As with other ant swarms, they can be confused with swarming termites, and it is important to know the difference for proper treatment. 

Homeowner Steps to Help Prevent Ant Infestations

As with many household pests, sanitation is important to minimize attractants. Our homes are attractive to insects because we offer them the necessities of life:  shelter, food, and water. Store food in glass or plastic containers with lids that can be tightly sealed. Do not leave out pet food overnight. If you have a severe ant infestation, place the food bowls in a shallow container filled with soapy water to keep the ants at bay. 

Outdoor ant infestations often turn into indoor ant infestations. Homeowners should reduce potential outdoor ant harborage areas around their home by keeping their yard clear of loose stones, boards, and bricks under which the ants can build nests. Establish a vegetation-free zone along the foundation to discourage ants from nesting too close to the home. Finally, do not spread mulch directly against the home’s foundation, and any mulch near the house should be no more than a couple of inches deep.

To the extent possible, seal gaps and cracks around the foundation.Realistically, locating and sealing gaps and cracks for mice is hard enough. For tiny insects like ants, it’s almost impossible. Still, don’t make it too easy for them and see obvious potential entry points.

If you do have an infestation, don’t make matters worse by haphazard DIY spraying. The last thing you want to do is force the ants to move their trail to another more inaccessible location that’s harder for the pest control technician to track. Also, ant baits are only effective if there are no food scraps that are more attractive. Food attractants must be removed. 

Ant colonies living within the walls may indicate that there are moisture problems in your home that need to be corrected. If there are wood-boring ants, which are attracted to soft water-damaged wood, there the home may be in need of repair.  

Professional pest control services have treatments for ants that are not available to the general public as well as specialized equipment to inject these applications into inaccessible locations. Pest infestations only get worse with time. DIY pesticides in homes are not only potentially hazardous, they are also ineffective and spread the infestation, making it even harder to treat. In the long-run, it’s less expensive and less aggravating for a pest control service to resolve the infestation while it is still in its early stages.