Nov 14, 2011 – The Many Ways To Kill Them
QUESTION:
German cockroaches: before we seal around pipe openings under sinks of apartments, is it best to leave gel bait on pipes, spray in gap with insecticide/igr mix, or dust?
ANSWER:
Good question, and I think we should consider what our longest term goal is when we put the insecticide into that gap that then is permanently closed. By the way, wonderful that you consider this IPM step, rather than the idea that every time you visit this account you add another application of contact insecticide into that opening. So much better, I believe, to just eliminate the opening.
Since we can only kill a cockroach one time perhaps we should look at the products that are going to provide the longest residual once we close an opening. Since it is possible that future roaches could move around in the void behind that former opening it would be desirable to kill those as well. Sprayed products and baits are going to have a relatively short residual or acceptance - months perhaps, but still short. But, dust formulations of inorganic active ingredients will last for many years if that void inside remains dry. Since we still believe that actives such as silica gel dust (Drione, Tri-die) or Diatomaceous Earth (MotherEarth D, Alpine D) can be very effective on cockroaches, these might be the best choice. They also present the least hazard to any people or pets that might possibly contact them in the future.
Puffing the dust in with a hand held bulb duster or plunger duster like the Mini Dust-R will create some turbulence that helps to push the dust further into the void, and if you really wanted to get the dust dispersed well you could go with a small battery operated duster such as the Exacticide or Power Puff. These look like cordless drills and run on a rechargable battery, and are very convenient for dusting into voids through small openings.
Injecting an IGR ahead of time, perhaps from an aerosol to keep the interior of that void dry, might be useful too. If roaches are inhabiting the void this could be very helpful in stopping the development of new adult roaches from either eggs or early nymphs.
View past Ask Mr. Pest Control questions.
German cockroaches: before we seal around pipe openings under sinks of apartments, is it best to leave gel bait on pipes, spray in gap with insecticide/igr mix, or dust?
ANSWER:
Good question, and I think we should consider what our longest term goal is when we put the insecticide into that gap that then is permanently closed. By the way, wonderful that you consider this IPM step, rather than the idea that every time you visit this account you add another application of contact insecticide into that opening. So much better, I believe, to just eliminate the opening.
Since we can only kill a cockroach one time perhaps we should look at the products that are going to provide the longest residual once we close an opening. Since it is possible that future roaches could move around in the void behind that former opening it would be desirable to kill those as well. Sprayed products and baits are going to have a relatively short residual or acceptance - months perhaps, but still short. But, dust formulations of inorganic active ingredients will last for many years if that void inside remains dry. Since we still believe that actives such as silica gel dust (Drione, Tri-die) or Diatomaceous Earth (MotherEarth D, Alpine D) can be very effective on cockroaches, these might be the best choice. They also present the least hazard to any people or pets that might possibly contact them in the future.
Puffing the dust in with a hand held bulb duster or plunger duster like the Mini Dust-R will create some turbulence that helps to push the dust further into the void, and if you really wanted to get the dust dispersed well you could go with a small battery operated duster such as the Exacticide or Power Puff. These look like cordless drills and run on a rechargable battery, and are very convenient for dusting into voids through small openings.
Injecting an IGR ahead of time, perhaps from an aerosol to keep the interior of that void dry, might be useful too. If roaches are inhabiting the void this could be very helpful in stopping the development of new adult roaches from either eggs or early nymphs.
View past Ask Mr. Pest Control questions.
