Sep 11, 2011 – A Unwelcome Mat For Scorpions

QUESTION:

I have reviewed most of the questions and answers submitted to you on scorpions and I am on board with all the chemical and non-chemical solutions you suggest. My question is how do scorpions get into homes? I would like to attack our ever-growing problem in Las Vegas by concentrating on entry areas.

ANSWER:

I'm really pleased that you are taking this necessary IPM approach to scorpion control, with the recognition that reliance on chemicals alone simply is not the best long term solution. Bugs of all kinds exist around our structures and a great many of them provide some benefit to our landscapes and the general environment. This may be due to their feeding on other insects, as scorpions do. While we can acknowledge that these are beneficial creatures we still don't want them wandering around on our bedroom floor at night, so keeping them OUT of the home is the most important aspect. Attempting to kill all arthropods that live in our yards is inappropriate and would require a terrible over-use of insecticides. Whether all of your customers like it or not they really do need to accept some tolerance and understanding of the living things around us.

If we "think" like a scorpion we recognize that we like to hunt at night and hide during the daytime, and we'd prefer to hide under something that provides darkness and some level of moisture. We hunt for other arthropods as our food, so we rely on having that prey available to us relatively near to where we hide. We are opportunists that investigate places where we may get lucky and find some food, and will crawl into and under other things in the hope of finding some insect hiding there. In this activity we often end up crawling along the base of the outside wall of a home, and if some gap presents itself we may crawl into it to look for food. If we are Bark Scorpions such as the Centruroides species found in the Southwest states we may also climb trees to look for insects, and if that tree or shrub happens to be touching the roof of a home we may end up on the roof and now find other gaps to move through. The inside of a home really is a foreign environment for us, and if we are trapped inside we likely will die, since proper food and harborage may not be available.

So, as the PMP we look at these activities of the scorpion and try to put up roadblocks. We eliminate other arthropods on a property so that scorpions have no reason to hang around there. We remove, where we can, outside harborage opportunities to limit the number of scorpions that can live on a property. We create barriers of open ground around the structure to discourage these secretive animals from spending time out in the open, for even a scorpion will have its own enemies that want to eat it. We carefully examine the trees and bushes around a structure to be certain that no branches or foliage touch the structures, and use a pair of pruning shears as one of our pest management tools. We carefully inspect the outside of the structure from soil to roof line, knowing that scorpions could possibly climb a rough wall too, and identify all gaps wide enough to allow these flattened critters to squeeze through.

Common entry points are exterior doors that are not well fitted, such as garage doors and side doors of garages. These gaps can be close with weather stripping and brush or plastic strips under the doors, and can be installed by the PMP as another valuable and legitimate service in the overall pest "management" effort. Even windows may have gaps, and in areas like Las Vegas people may be inclined to leave windows open at night and rely on screens to keep critters out. Screens are notoriously poor fitting or damaged to allow scorpions in, and these can be repaired or replaced as needed to seal the area around that screen framing. There are always wide gaps under the eaves of the roof line, and while it may take time to accomplish these can be fllled with caulking and then painted, or filled with some other appropriate material. These gaps admit a lot more than just scorpions, and "pest proofing" a home accomplishes a great deal for a very long time, and greatly reduces the need to use pesticides to kill bugs.

You can also monitor the interior using glue traps placed fairly liberally, but along likely travel paths such as edges of walls. Finding scorpions in the traps could help you to identify possible entry points near that location that you had not found earlier. Make sure all vent screens to attic or crawl space are in good condition with a mesh small enough to keep scorpions from crawling through, and repair those with holes or where the screen has pulled away from the edge. The customer needs to be educated on the wisdom of this approach, and I hope that most homeowners, when they recognize the long term benefit of keeping scorpions out with minimal use of toxic tools, will buy into it and help as well.

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