[Ant Control] Carpenter Ants Up Close

Photo by Henrikhl, Dreamstime.com

I became an avid student of carpenter ants in hopes to redeem my professional dignity after my first failed treatment. The account in question, a house in the West End of Richmond, Va., sat on a plot of land no more than 150 feet from the James River. The initial inspection did not show much at all, in fact the first two or three visits were on cloudy and unusually cool days for summertime. The only evidence I had to help identify the pest species was the description from the owner, “I’m seeing huge, intimidating black ants everywhere! And I want them gone!”

OK, so it didn’t take a pest control veteran to figure out that the pest species was indeed the black carpenter ant (Camponotus pennsylvanicus). What it did require was someone who understood the life cycle, colony structure, eating habits and required harborage — none of which I knew thoroughly. Since the house was so close to the James River, I could not fire up the 100-gallon rig to create a hefty chemical barrier for fear of creating a runoff situation and to avoid any type of drift.

So I pulled out my trustworthy air-compressed spray can and saturated the foundation. After several premature, “that ought to do it” statements, both my customer and her neighbors were quite disappointed. What was I missing? Was this some new breed of carpenter ant that smiled in the face of death and drank my insecticide for breakfast? After receiving an earful of disappointment and regret, I convinced my customer to allow me one more shot.
 

What to do? With only two days before the treatment, I made my way to the library. There I found books similar to a book that was already in my possession — NPCA’s Field Guide. I spent nearly six hours reading and learning about the carpenter ant. When I returned to my customer’s house, I was more than equipped with knowledge and confidence. The problem was solved by simply detaching the clothing line that connected the house to a huge tree where the ants were living. After weeks of headaches, confusion and dismay, the solution was not in a chemical formulation alone. Somehow, at that moment, I knew that there was a universe of information, techniques and resources I had yet to discover.

A decade later, I was afforded the opportunity to spend a year in the Dodson Urban Entomology Lab in Blacksburg, Va., feeding, watering and observing Dr. Dini Miller’s colonies of Blaberus giganteus, Periplaneta americana, Blattella germanica and Cimex lectularius. I can say that not one second was wasted.

However, the most fascinating species to care for were the two colonies of carpenter ants. I spent hours watching them forage, consume sugar water (with red food coloring) and feast on wounded American cockroaches. This lab time was in combination with textbook descriptions, studying theories of ecological dominance and developing an in-depth understanding of Integrated Pest Management (IPM). All of this helped greatly in being able to develop customized treatment strategies. There is no rubber-stamp strategy sufficient for every single home, regardless of the similarities. There are, however, means and methods that allow for complete customer satisfaction and promote environmental responsibility.
 

Defining IPM. IPM dictates that before any thought goes into a treatment strategy, positive identification needs to be made first. Too often a customer will exaggerate the size, out of entomophobia, and this could lead you down the path of a misapplication, an unsatisfied customer and even worse — a marred reputation. Once a positive identification has been made, we can move on to determine the approximate size of the population.

If your client’s property is being invaded by small workers, this indicates that the colony is rather young and newly formed. A new queen nourishes her first born with the flight muscles from her thoracic region, therefore, the first workers are relatively small in comparison to the next generation of sisters. Having a working knowledge of not only the life cycle but understanding the colony hierarchy will help you design an effective program.

In most situations, the carpenter ant nest will be extremely hard to find, but this does not necessarily spell failure. Black carpenter ant photo courtesy of Clemson University — USDA Cooperative Extension Slide Series, Bugwood.org

Once the colony has grown to the second and third generation, it begins to socially function. The queen initiates job assignments and each ant falls into line. The colony is separated into workers who forage for food and workers who attend to the needs of the nest. The queen steadily produces eggs.

Whether the colony is small or large, you must identify the needs of the survival triangle: food, water and shelter. I always search for a structural satellite nest (shelter) first. A satellite nest by definition is a temporary dwelling. It does not require the mandatory moisture content like the parent colony because there are no eggs in this nest — only workers, pupae and mature larvae. Therefore, you may find a satellite nest in the insulation under the house, in the wall voids or even around the dishwasher. Many extension agencies’ literature suggests that locating the nest prior to a treatment is crucial to the success of any given program. In most situations, the nest will be extremely hard to find, but this does not necessarily spell failure — there are two more needs that can be sought out and stressed or eliminated.

While water is an absolute necessity for all living creatures, carpenter ants can acquire their hydration from a food source if necessary. Other sources, such as condensation, droplets on leaves, puddles in shaded areas (but more commonly backed-up and leaf-littered gutters) provide an adequate amount of water for this insect. Of the three elements needed, shelter and water can be obtained outside of the client’s home. A professional may never truly find the nest or the source that provides hydration for a colony — but if there’s a constant ant trail in the house, there is a food source.

Common knowledge suggests that most species of ant love sweet sugary foods and juices. This may hold some truth but carpenter ants will feed on an array of foods, including proteins and starches. Have you ever noticed they rarely stop to eat? Of all the bread crumbs they are hoisting away, why don’t they stop for a lunch break to re-energize? The reason is if the substance is not a liquid, the adult worker cannot consume it. Those huge and strong mandibles are for pulling, fighting and carrying only. The worker carries the food particles back to the nest and feed them to the larvae (wormlike immatures), who possess chewing mouthparts. They chew the food and then regurgitate it to feed the entire colony including the egg producing queen (trophallaxis).

Formulation Choice. So why did I spray to create a chemical barrier on my first carpenter ant job? Oh that’s right, because spraying was the only technique I knew. Locating the nest may be virtually impossible and determining a viable water source may present a barrage of possibilities but you know absolutely that the carpenter ants are entering the house for food. Having an understanding of trophallaxis encourages me to utilize a method to eliminate the queen as quickly as possible. Therefore, granular baiting is the technique and formulation of choice for me.

This formulation’s label does allow for broadcast applications but I choose to use it in a more controlled environment. In cases where I cannot find one single ant during my inspection, I will sprinkle a few particles at each corner on the exterior and within minutes, I’ll see activity on at least one location, if not all. This formulation is great but is susceptible to moisture and may have an odor that may attract non-target domestic animals. To eliminate the threat of being compromised by water and also to avoid exposure to children and domestic animals, I prefer to use rodent stations as shelter and protectant for the bait.

Over the years, I have obtained favorable results by creating a chemical barrier and still find success with this treatment. Now that I find myself in a position to not only teach pest control techniques but to preserve my environment, my choices for everyday strategies are greatly influenced. This is why my IPM programs usually lead to granular baits for carpenter ants. IPM is more than just professional lingo and by no means translates into “no chemical.” It is a methodology that can be used in every aspect of the pest management professional’s daily routine.

The author is with Environmental & Consumer Educators, Spring Valley, N.Y. He can be reached at dbailey@giemedia.com.