[Annual Cockroach Control Issue] IPM Basics for Cockroach Control

The German cockroach is not at the top of many pest management professionals’ list of "money bugs." If you have followed the articles published in PCT magazine throughout the past five years it seems evident that cockroaches are now playing second or third fiddle to other pest complexes as far as frequency of calls and/or revenue dollars. There just doesn’t seem to be a lot being discussed in the industry about German cockroaches.

Several university urban entomology programs have shifted research focus away from exploring German cockroach biology and behavior as it pertains to feeding, foraging, bait palatability, insecticide resistance and integrated control strategies. This is clearly evident by looking at the number of German cockroach presentations at entomology conferences and symposiums. Why is this so?

It is unlikely that any single factor is solely responsible. But, it is hard to imagine that the great "bait race" to develop highly palatable bait bases coupled with highly effective active ingredients hasn’t had something to do with it. If by chance your business has experienced a downturn in German cockroach work, it is easy to ignore reviewing the basic strategies to successful German cockroach control with your technicians in preparation for the eventual roach calls that will come in. New technicians may not even receive full German cockroach treatment training beyond gel baiting with multiple types of gel baits from various manufacturers.

Make no mistake about it, the German cockroach is a great testament to the ability of our best known insect pest complexes to adapt and survive. I agree with Dr. Austin Frishman, who always says, "The roaches will always win in the long run." I am therefore not convinced that they are going to go away anytime soon. What follows are some basics to take into account when training and preparing your employees to effectively employ an integrated strategy to German cockroach control.

IPM IS BETTER. We have all heard the phrase "Integrated Pest Management (IPM)." In short, IPM means using not only a variety of chemical types and forms but other non-chemical strategies as well. Are you incorporating IPM into your German cockroach treatment program? If not, you may experience frustration with treatment failures due to possible insecticide resistance, or when baiting perhaps even bait avoidance or behavioral resistance.

On the flip side, it typically costs money to practice a true IPM approach in all situations. It is sometimes more economical to use one major chemical, whether it is a residual or a tube of the latest greatest gel bait. A single formulation application approach may work for one-time treatments of a non-problem account but be cautious of over simplification. Past research indicates that this can rapidly accelerate the build-up of resistant individuals in an active infestation of German cockroaches. Classic Integrated Pest Management concepts specific to German cockroach control may include the following:

Proper Inspection And Surveying The Scope Of The Infestation. The cornerstone of any IPM program is proper pest identification and with the German cockroach this should be fairly easy to do. When the heavy infestation call comes in, cockroach activity is easy to spot by looking for live roaches, dead bodies or frass build-up in classic German cockroach harborage sites, such as cracks and crevices. In extreme cases, where a population has been left to flourish under poor sanitation conditions and with plenty of food and water available, German cockroaches can build up enormous numbers, whereby it is difficult to inspect a crack or crevice without a few live individuals present.

In other accounts where a cockroach or two have been sighted or reported the inspection takes on a more important role. Key areas near potential food or water sources and high humidity conditions should always be inspected first. The inspection can be gradually branched out from these areas if no cockroaches are found. Ensure that technicians are well equipped with two important inspection tools – a good reliable flashlight and a flushing agent.

Sanitation. Even for a German cockroach it is difficult to survive in an environment where proper sanitation has been employed and diligently practiced. Whether in the home or restaurant setting, poor sanitation is a major contributing factor to cockroach survival. Upon initial inspection, pointing out these poor sanitation conditions, with an action plan for correction, which may not be obvious to the homeowner or management, can be the difference between a successful or unsuccessful treatment program.

Of course the three big things to watch for are potential food, water and shelter sources. Sanitation is especially important when attempting to employ baits to gain control. Baits are food and must effectively compete with other food sources scattered throughout the environment. Removing any and all sources of food for the German cockroach (which can be about anything with calories in it) can greatly enhance the effectiveness of your baiting programs.

Chemical Rotation/Bait Rotation. In apartment complexes and commercial facilities that are under continued service, remember to rotate residuals and baits alike. This has been demonstrated to greatly reduce the likelihood of resistance problems.

Vacuuming. In accounts with many visible roaches that you can see it’s a good idea to get as many of them as possible before you treat. This may be easier said than done but there are a few devices available on the market to help you with this task. Vacuums do a good job (providing you can reach the cockroaches) and are a great component to the IPM program in that no conventional chemicals are being used.

Sticky Traps. Use sticky traps to monitor low-level infestation accounts. The great thing about monitor traps is that sometimes the staff and/or homeowner become involved in the monitoring, telling you where they have seen a stray nymph or two crawling near the trap area or in another area. Using monitoring traps can help you pinpoint applications or avoid them altogether. In some instances they have even been used intensively to significantly reduce German cockroach populations to an acceptable level of control without the usage of any chemical treatment at all.

Using Chemicals Other Than Baits. Since 1985 we’ve heard more about cockroach baits than any one other method of treating these critters. Baits have become the standard method to control German cockroach infestations and with good reason. They are unobtrusive when applied correctly, they allow for pinpoint treatment, they work relatively fast, very little product is needed in most instances, they are successful over a broad range of infestation types and are labeled for use in almost all treatment areas including food preparation/handling areas. The list goes on. Most bait formulations until just recently (see the cover story of the January 2003 issue of PCT) have not exhibited signs of failure due to resistance/advoidance of any type. Some newer technicians, hired during the heyday of baits, may not even be aware that there are other, alternative chemical formulations available to tackle the problem.

Three other forms of chemicals readily come to mind that, when used properly following the basic guidelines outlined above, can give control satisfaction every bit as good as baits: dusts, insect growth regulators and liquid or foam residual crack and crevice treatments. These bait alternatives can be especially effective in accounts that are taken over that were previously under strict baiting programs. Again, chemical rotation or simultaneous usage of more than one chemical type may not be the cheapest, quickest plan of attack but it can be the solution to an already problematic "bait only" account and it can furthermore potentially help to reduce the propagation of the bait avoidance aversion phenomenon.

CONCLUSION. Take some time to review these basic strategies, share them with your technicians, and make sure that new technicians are not solely trained in gel bait application techniques for German cockroach control. There are other tools at your disposal that will let you attack any German cockroach problem. Be ready to use all of these strategies when the time comes.

Will the German cockroach return as a major money bug? Or did they really leave us in the first place? Either way, be prepared with a total control program when the inevitable call comes in.

The author is a research scientist at SC Johnson & Son Inc., Racine, Wis., in the Insect Control RD&E Division of the company’s Worldwide Consumer Products Group. He can be reached at rkopanic@pctonline.com.