[Technically Speaking] They’re as good once as they ever were

The title of this article is a knock-off of a line from a song by Toby Keith. In the song he says, "I’m not as good as I once was, but I’m as good once as I ever was." Recently I have spoken with a number of pest management professionals and reflecting on these conversations and my experience over the last several years, it may be time to revert to old fashioned cleanouts when accounts are heavily infested with German cockroaches.

When we encounter new accounts that have heavy infestations of cockroaches it is important to consider why the problem is so bad. Some possibilities include:

• Poor service from the previous pest management firm.

• Lack of tenant cooperation.

• Lack of management support, e.g., only service complaints with no scheduled rotation.

• Behavioral resistance to bait products.

Oftentimes it is not easy to deduce what the cause of the problem is but if we can realistically eliminate the first three factors there is no easy way to determine if behavioral resistance to bait is the problem. Regardless of the reason, a decision must be made on how to proceed and get the situation under control.

BACK IN THE DAY. Back in the day of the "spray and pray" approach to pest management, problems evolved from the overuse of residual insecticides, i.e., physiological resistance. A lot of effort was spent testing for cockroach resistance and coming up with schemes for addressing the problem, mostly through rotation of products. Unfortunately, resistance testing took a lot of time and resources, so rotation was haphazard and unscientific. Many times, because of cross resistance, this led to more serious resistance problems.

Some new active baits and baiting formulations were developed at an opportune time. Traditional spray active ingredients were not performing as well as they had and there was increased emphasis on least-toxic approaches to pest management, particularly where human exposure was greatest — in the home.

At the outset baits were very effective. The new AIs and the fact that the products were readily ingested overcame physiological resistance in cockroach populations. The baits were consumer friendly: there were no volatile organic compounds to be concerned about; and they could be applied with minimal preparation, such as emptying cabinets (although this remained a helpful practice).

Despite these favorable attributes, baits had several shortcomings. They do not rapidly kill cockroaches, thus the "thrill of the kill" is gone. Large amounts are required to eliminate large cockroach populations. Misapplication and over application result in ugly residues.

However, the most recent development with baits, behavioral resistance, is the most disheartening. Despite the adjustments manufacturers make to their products’ matrixes, we are foolhardy to believe that cockroaches will not (through genetic adaptation) continue to win the war and persist at unacceptable levels. They have adapted successfully to environmental changes for more than 350 million years and everything humans have to offer as far as pest control — they are survivors.

This is a population problem and not a universal problem with all German cockroaches. Fundamentally, a population is a genetically isolated group of animals of the same species, in this case German roaches. It is possible in an apartment building to have many German cockroach populations that appear the same but are physiologically and/or behaviorally different. Thus, these populations respond differently to insecticides and/or baits depending on their historical exposure to these products and the survivors’ reproductive success.

The only way to be certain of eliminating these adaptations is to eliminate the specific gene pool by eradicating the population. This does not prevent immigration of another population into the area that may have similar or very different physiological and/or behavioral differences.

WHAT TO DO? Considering the facts that there is known behavioral resistance to baits, baits have been widely used in the industry for the last 10 years, and there is a need to reduce heavy populations quickly, in my opinion, there are two options:

• Vacuuming — this method is preferred by IPM purists but is labor intensive; it can be used when there are only a few units requiring an intensive treatment; unfortunately, there is no residual activity; and it rarely removes all of the roaches. My experience in vacuuming to remove heavy populations over the last two years is twofold: apartment and restaurant management rarely will pay for this type of service; and PCOs will not provide it when they are only getting $5 per unit.

• Clean-out spraying — in the absence of this type of service for almost 10 years it is unlikely that there will be resistance problems with the currently registered residual insecticides. Providing that appropriate preparation is made, e.g., removing all of the items from cabinets and eliminating clutter, these products if applied correctly leave a residual and can eradicate the population. The advantages of cleanouts are that they produce immediate results and are cost effective.

When encountering apartments and restaurants with heavy cockroach populations, the best course of action would be to:

• Perform a thorough inspection, identifying those units/areas with moderate-heavy infestations and complete a sanitation report for management.

• Require tenants (via management) that these units be prepared for treatment, i.e., remove all items from cabinets and perform basic sanitation.

• Arrange for assistance from management to pull out stoves and refrigerators.

• Perform a thorough crack and crevice treatment.

• Perform follow-up inspections within two weeks and bait as needed.

• As needed, bait other units and areas.

• Use baits as needed for routine maintenance in all units.

I am not advocating a return to baseboard spraying or even a return to their routine use for cockroach control. However, cleanouts, although not as popular as they once were, in some situations may be as good once as they ever were.

The author is president of Innovative Pest Management, Brookeville, Md. He can be reached at rkramer@giemedia.com.