QUESTION:

What is the most effective way to get rid of German roaches?

ANSWER:

I really like a message from Dr. Robert Corrigan a few years ago at a national pest conference, where he said "everything changes when resources are limited". Now, he was speaking on rodent control, but this message is absolutely as pertinent to cockroach control as it is to rodents, and it is the essence of IPM. We must recognize that these cockroaches are present in a structure for one reason - they are finding everything they need to survive, and in general those "things" should not be available to them. These are food, water, and harborage. What is the difference between an apartment with a huge roach problem and the apartment with no roaches? Probably sanitation.

So, here is how I would start a discussion on successful elimination of German roaches. We know they likely are living entirely indoors, and therefore they are finding all the food they need, plenty of moisture since this species does need moisture, and plenty of tight, enclosed hiding places to sneak back into every morning. Your management program must begin with an inspection to locate all of these resources used by the roaches, and then develop a plan for eliminating all of them. This may take quite awhile to achieve, but bit by bit you should be able to work with the customer to clean up food residues on surfaces, to store food so that roaches cannot get to it, to repair all moisture sources, and to fill in cracks, crevices, and holes leading to voids so that the roaches can no longer get into or out of them. Every step you make in this direction means that many less roaches that can survive in an account, so even if you cannot be successful in eliminating 100% of these things you at least can take care of a large chunk of it, and every success you make means less roaches.

Another great quote is that "pesticides cannot overcome bad sanitation", and expecting insecticides to be the cure-all is fairly optimistic. You must combine the use of insecticides with these other necessary steps in your IPM program, and whether you think of it as IPM or just plain old "Sanitation" doesn't really matter. Cleaning up the roach's resources is IPM. It would be valuable to discuss the options with the customer as well, as you will get a wide disparity in attitudes about what they want done. Some are going to cooperate very well once you enlighten them on the contributing conditions that led to the roach invasion, others will think the whole solution should be left up to you. Thus, you do what you can and keep in your mind that you must be profitable on the job. But, if the customer's expectation is that they will do nothing and you will eliminate every roach, then perhaps walking away from the account is the best thing for you.

So, sanitation, exclusion and repairs are important. Consider the use of a high powered vacuum initially, as this removes large numbers of roaches and egg capsules. Consider the use of a steamer in certain places, as this quickly kills exposed roaches in crevices and perhaps sanitizes things a bit too. Use bait products, and gel baits are excellent for German roaches but need to be placed as small "pea-sized" spots directly in crevices or voids. This roach prefers to feed in seclusion where it is safer, rather than out in the open on counters. Use "crack and crevice" treatments of residual insecticides, meaning you inject the product directly into those hiding places you know or suspect are harboring roaches. This not only keeps the product away from human contact, prevents it from being removed by cleaning, but also puts the roach and the active ingredient into contact for the longest period of time.

Use insect glue traps throughout the whole process, as this can tell you where the roaches may be coming from as well as monitor your success. Consider the use of a deep void injector such as the Patriot, Actisol, or B&G P.A.D.S., as these allow you to "fog" within wall voids with a residual insecticide, again bringing the active ingredient right to the hidden roaches. Do NOT rely completely on insecticides unless this is all you have left, but strongly seek the cooperation of the customer in eliminating the contributing conditions.

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