Treatment necessary to counter ants

For many of us, our homes are safe, warm and perfect for raising families. Unfortunately, many pests have realized this as well.

As we move into spring, pests, such as ants, may become a problem. They are actively looking for food or a new place to nest — a search that could find your home. So, if you turned on the kitchen light last night and found hundreds of ants covering the counter top, then here are some strategies to control ants.

We typically think of ants as outdoor pests that invade the picnic table. However, there are more than 100 common species recognized as household pests that nest indoors behind molding, baseboards and counter tops. In either case of an indoor or outdoor ant, control begins with finding the nest — a task much easier said than done.

Ants typically follow regular routes or chemical trails between the food source and their nest. Watch the ants to locate their trail. Try to follow them back to the nest. I once followed a trail from the kitchen counter to a nest 20 feet out in the yard. The journey took them through a tiny hole in the kitchen window, across the roof of a covered porch, down the drain spout of the gutter, over a small concrete walk and into the grass another 5 feet.

If you are not lucky enough to find the nest, you might consider treating the exterior of the house using an insecticide labeled for use as a lawn treatment. Apply the treatment in a 2- to 4-foot wide area around the entire building. This treatment is temporary and more treatment may be necessary.

Some examples of exterior use chemicals are carbaryl (Sevin), Acephate (Orthene) and other various synthetic pyrethroids such as cypermethrin, cyfluthrin, lambda-cyhalothrin, bifenthrin and permethrin.

Inside efforts should center around baits. Foraging workers feed on the bait and return it to the nest where they share it with the rest of the colony. However, baits are slow-acting and it may take several weeks to see a reduction in numbers. Likewise, not all ants are equally attracted to baits. Ant baits that you buy in stores will be attractive to some species but not others. Experiment with foods that are attractive to the ants. Try peanut butter, sweets, fruit or meat products.

A homemade bait can be made by mixing two parts boric acid to 98 parts of food attractant (1/4 teaspoon of boric acid to about 4 tablespoons of food attractant). These baits should be placed on small jar lids, pieces of cardboard, in straws or something similar. Locate the feeding stations in places where ants are commonly observed.

Finally, consider steps to prevent entry. It is generally assumed that careless cleaning habits in the kitchen will make the area more susceptible to ants. Of course, it is hard to be specific about how clean is clean enough. However, when faced with an ant problem, increased efforts of proper food storage, waste disposal, and cleaning of kitchen surfaces will be needed. In some cases, entry points can be sealed or caulked to prevent entry.


— Bruce Chladny is horticulture agent at K-State Research and Extension-Douglas County. For more information, call him at 843-7058 from 8 a.m. to 5 p.m. weekdays.