QUESTION:
I have two mobile homes, where one had a bad German roach problem and now the other also has roaches and never had them before. What is going on? Am I doing anything wrong? She keeps it very clean. What do I need to do?
ANSWER:
It may sound trivial, but be sure of the kind of roach you are finding in this second mobile home. California has good populations of the Vaga roach, which strongly resembles its cousin the German roach, but which lives outdoors, comes to lights, and flies. Just possibly you or she has found a few of the Vaga roaches in this clean home and mistaken them for Germans. The Vaga roach has a distinct black area down the front of its “face” between the eyes. If these definitely are Germans it would not be unheard of for them to occupy a home that seems clean to you and me, but still holds food and harborage opportunities for the roaches. If there has been that really bad infestation in a mobile home immediately adjacent to this second one it could be very possible for some of the roaches to be forced to look for less-competitive accommodations, and they may have moved out and over next door. It’s also possible that both of these tenants shop at the same infested grocery store, and the odds simply were that the second home was going to get some hitchhiking roaches at some point in time.
So, I don’t know that YOU are doing anything wrong except believing that somehow it is your fault, which it probably is not. You now need to do a very thorough inspection of this second home to determine the extent of the problem, to identify the food resources the roaches are being offered, to identify moisture sources that do not need to exist, and to identify exactly where the roaches are hiding so you can deal with them at that point. These roaches could not survive in this very clean home if there were no food, water, and harborage available to them, so at some level these must be present and food, at the least, can be eliminated. Discuss this diplomatically with the customer so that she does not feel she is being accused of being unsanitary. Even low levels of spills and clutter will support some roaches, but the customer must cooperate with you in your effort to remove the resources the roaches are using and to clean as thoroughly as possible.
Start with the inspection, recommend all the sanitation corrections needed, where possible use caulking to close all openings to harborage, use gel baits within crevices that are as close to the roach harborage as possible, treat directly into the harborage openings with a crack and crevice application, dust into walls with a residual dust (and silica gel or diatomaceous earth are good options), and place insect glue traps in various places to monitor your results or to inspect for additional roach populations you may not have discovered initially. If there are pets here their food should be placed only as they feed and then removed and sealed up until the next meal. Water dishes should not be left out at night. All other foods should be placed in sealed containers such as plastic tubs.
With the variety of selections we have for German roach control today these pests are not as invincible as they once seemed. Baiting continues to be excellent, and offer a bit of a variety of baits to see which ones they like. Some of the current aerosol products are excellent for the crack and crevice application, so discuss this with your local Univar sales reps to see which brands are giving the best results in your area. The inorganic dusts do a great job of killing roaches and lasting for many years in the future in case new roaches enter.
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