Scorpions are most common in the southern states from coast to coast, although they are found as far north as British Columbia. Most of the scorpions that invade homes or other buildings are generally not dangerous. While they will sting if someone accidentally contacts them, their sting is seldom more painful than that of a wasp or honeybee. There is one deadly species in southern Arizona and adjacent areas of Texas, California, and New Mexico. This species is not found in South Carolina or in the southeastern US.
Scorpions are attracted to areas that provide shelter, moisture and their prey: mostly insects. Scorpions often enter homes in the spring and fall but there is no clear evidence to indicate why scorpions will invade homes at certain times of the year and not at others. Once inside the home, scorpions prefer hidden places with cover. Scorpions can readily enter buildings through cracks 1/8 inch wide. Around the home scorpions may be found in accumulations of lumber, bricks, brush and trash. Certain ornamental ground covers such as large stones, mulch and bark provide good harborage for scorpions and such areas adjacent to a home may enhance the movement of these pests into a home.
Nonchemical control
A careful inspection and cleanup of the area is the first step in controlling scorpions. They are active at night, especially when temperatures are above 75 degrees. One can inspect an area at night with a flashlight to locate scorpions. When inspecting for scorpions, wear protective gloves and boots, and look under rocks, loose tree bark, around firewood, lumber, or other debris piled outside. Cracks and crevices in walls are also good hiding places for scorpions. Scorpions will go to moisture, especially under dry weather conditions, so look in areas that are moist. Other suggestions for long term nonchemical control include:
- remove all trash and debris. This is always a good recommendation since outdoor roaches and other pests on which scorpions prey are also attracted to trashy areas
- store firewood and lumber off of the ground, and keep it dry
- remove unnecessary rocks
- provide for good runoff of rainwater away from the house
- use small gravel as an ornamental groundcover immediately adjacent to the home, rather than any wood type cover
- seal any openings in outside walls with mortar or caulking
- screen and weatherstrip doors, windows and vents
- repair or prevent wet areas caused by plumbing leaks, air conditioners, etc
- use a dehumidifier in damp basements
Chemical control
Even if you decide to use chemical control, the recommendations for nonchemical control should be followed first. After applying the above measures, indoor and outdoor areas infested with scorpions may be treated with sprays or dusts of residual chemicals labeled for scorpions. One technique to treat scorpions is to concentrate them into a preferred habitat by spreading wet burlap or cloth on the ground near suspected infested areas. By grouping scorpions, chemical sprays can be applied to the collected individuals.
When using pesticides, check the label carefully to make certain that the product may be used for scorpions, especially that it is approved for use indoors if that is the intended area for treatment. FOLLOW ALL LABEL INSTRUCTIONS EXACTLY! Note that professional pest control operators have access to products and methods not available to the general public. If a heavy infestation of scorpions is a problem, contact such a professional.
Originally published 01/01