Sep 21, 2011 – Scorpions – Predator and Pest
QUESTION:
In your opinion what's the best chemical to combat scorpions?
ANSWER:
Trust me, I will get around to the chemical part of scorpion management eventually, but I still feel the need to discuss the other parts of an overall IPM program for scorpions. Chemicals alone are not likely to give the best results that you and your customer are looking for, and the customer needs to buy into the need for their cooperation in this too. I suspect that too many homeowners still perceive "pesticides" as the magic bullet that can overcome all obstacles such as sanitation, harborage, and exclusion issues that need to be addressed and corrected.
Harborage and sanitation probably are one and the same for scorpions. There are potentially dozens of places in a landscape or yard that could provide harborage for these nocturnal animals, and many of these sites are unnecessary. It could be firewood or lumber piled on the ground that instead should be stacked neatly OFF the soil and away from the structure. It might be other clutter such as old boxes or appliances tossed outside and left there. It might be landscape features such as rocks or boards that could somehow be better situated so scorpions could not get under them during the daytime. It is helpful to the homeowner to do your inspection of their property to point out and put in writing all of these possibilities, and the more they can correct these harborage sites the fewer scorpions can there be on the property and the further from the home they need to hide, reducing the chances they will attempt to enter the structure.
Exclusion is vital, and your inspection also looks for every possible crack, gap, or hole through which scorpions might move to get inside the home. Houses can be pretty porous, and even around my own home, which you might think should be managed perfectly to keep bugs out, there are many great openings to admit bugs. In your area you might also have the "bark" scorpions in the genus Centruroides, which are quite toxic and which can climb trees and walls, so your inspection of the exterior should include a look at trees and shrubs to see if branches touch the structure, and gaps under the eaves at roofline, since the scorpions can easily climb rough stucco walls.
I mention all of this because we should never come to rely completely on pesticides. They just don't last that long and we should have a good stewardship of their use and the environment by using them only when necessary. If scorpions are living on a property there are reasons they are able to do so. If they are entering the structure there must be openings available to them. Changing both of these conditions can dramatically reduce the need to apply toxins, and keep you from having to constantly apply the material to keep an effective residual in place. In addition, a constant exposure to insecticides is a great way to encourage a buildup of resistance to the active ingredients by the pests.
According to some of our folks in scorpion-infested Arizona the synthetic pyrethroids continue to be excellent for scorpion management, along with the other issues listed above. Microencapsulated formulations such as Demand and other lambda-cyhalothrin products seems to be a popular choice. The microencapsulation helps to protect the active ingredient from the intense heat of the southwest states, and lengthens the time the product is available. The capsules also may more easily adhere to a passing scorpion, giving a better chance to get the a.i. onto and into the bug. If you have access to voids that the scorpions may hide within you could use a residual dust, and this may include dusting into access points around the perimeter of the structure.
View past Ask Mr. Pest Control questions.
In your opinion what's the best chemical to combat scorpions?
ANSWER:
Trust me, I will get around to the chemical part of scorpion management eventually, but I still feel the need to discuss the other parts of an overall IPM program for scorpions. Chemicals alone are not likely to give the best results that you and your customer are looking for, and the customer needs to buy into the need for their cooperation in this too. I suspect that too many homeowners still perceive "pesticides" as the magic bullet that can overcome all obstacles such as sanitation, harborage, and exclusion issues that need to be addressed and corrected.
Harborage and sanitation probably are one and the same for scorpions. There are potentially dozens of places in a landscape or yard that could provide harborage for these nocturnal animals, and many of these sites are unnecessary. It could be firewood or lumber piled on the ground that instead should be stacked neatly OFF the soil and away from the structure. It might be other clutter such as old boxes or appliances tossed outside and left there. It might be landscape features such as rocks or boards that could somehow be better situated so scorpions could not get under them during the daytime. It is helpful to the homeowner to do your inspection of their property to point out and put in writing all of these possibilities, and the more they can correct these harborage sites the fewer scorpions can there be on the property and the further from the home they need to hide, reducing the chances they will attempt to enter the structure.
Exclusion is vital, and your inspection also looks for every possible crack, gap, or hole through which scorpions might move to get inside the home. Houses can be pretty porous, and even around my own home, which you might think should be managed perfectly to keep bugs out, there are many great openings to admit bugs. In your area you might also have the "bark" scorpions in the genus Centruroides, which are quite toxic and which can climb trees and walls, so your inspection of the exterior should include a look at trees and shrubs to see if branches touch the structure, and gaps under the eaves at roofline, since the scorpions can easily climb rough stucco walls.
I mention all of this because we should never come to rely completely on pesticides. They just don't last that long and we should have a good stewardship of their use and the environment by using them only when necessary. If scorpions are living on a property there are reasons they are able to do so. If they are entering the structure there must be openings available to them. Changing both of these conditions can dramatically reduce the need to apply toxins, and keep you from having to constantly apply the material to keep an effective residual in place. In addition, a constant exposure to insecticides is a great way to encourage a buildup of resistance to the active ingredients by the pests.
According to some of our folks in scorpion-infested Arizona the synthetic pyrethroids continue to be excellent for scorpion management, along with the other issues listed above. Microencapsulated formulations such as Demand and other lambda-cyhalothrin products seems to be a popular choice. The microencapsulation helps to protect the active ingredient from the intense heat of the southwest states, and lengthens the time the product is available. The capsules also may more easily adhere to a passing scorpion, giving a better chance to get the a.i. onto and into the bug. If you have access to voids that the scorpions may hide within you could use a residual dust, and this may include dusting into access points around the perimeter of the structure.
View past Ask Mr. Pest Control questions.
