QUESTION:

I was wondering how you would approach treating for earwigs which are entering a home. There is a moisture issue in the cellar.

ANSWER:

I'm glad you mentioned the moisture issue as this tells me you are tuned into Contributing Conditions. If everyone hasn't figured it out by now I am very much into looking at the overall picture so we can minimize our reliance on insecticides. Chemical tools are a great way to give immediate relief from a pest problem while we work to correct the reasons that the pest is there, where possible, and I recognize that this is not always the perfect answer. But, if we do nothing to correct issues such as outside harborage opportunities, entry opportunities, food and water resources, then we can kill all the bugs but should expect more of them to find their way back in a short period of time. Maybe this is good job security, but probably not what the customer is hoping for.

Earwigs and many other nocturnal insects do seek moist conditions, and this may not be what is drawing them into the cellar, but it could be helping these insects to survive there for a longer period of time. That moisture is also a situation that could cause other problems, such as decay fungus on wood or mold on other surfaces, and obviously moisture problems should be dealt with on the interior. This may not be an area of expertise for you, but you should recommend to the customer that they hire someone who can determine why this moisture exists and  what corrective actions could be taken to eliminate it. This will at least help with the issue of earwigs, not to mention all those other moisture lovers like springtails, psocids, fungus gnats, etc.

I think you could easily spray a residual material and kill a lot of earwigs, inside and out, but a slow walk with a critical eye around the exterior should help point out some other things. Ideally we leave a bare area around the perimeter of the foundation, at least bare with respect to turf, weeds, or groundcovers. This 2-foot perimeter could be covered with crushed rock or gravel, but not with mulch or bark, as these provide hiding places for earwigs and other bugs. It also should be as dry as possible, and if there is irrigation or poor drainage these could be corrected so that water does not settle or land next to the structure. Are there other things piled against the foundation, such as old boxes, firewood, etc. - things that provide hiding places for the earwigs directly against the foundation? Are there trees or shrubs whose branches contact the structure and could be trimmed away. Are there openings that can be permanently filled in to prevent entry by bugs? These you yourself could seal up with appropriate building materials, many of which Univar sells as exclusion products for rodents, bats, bugs, and other crawling pests.

As much as you can make life uncomfortable for the earwigs both inside and outside the less likely you will be to have many of them around the home. If the moisture problem inside can be repaired then those few earwigs that do make it in, and it is always going to happen, are more likely to die from desiccation sooner than they do now. For chemical treating I would suggest one of the microencapsulated products, as these offer perhaps the longest residual due to the microencapsulation of the active ingredient, they hold up better on damp surfaces, and it is easier for a passing crawling bug to pick up some of the capsules as they pass by. Some of these products have good and broad labeling for both inside and exterior uses, making it easy for you to stay within the Label and even to treat areas around the property where you suspect the bugs to be hiding.

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