Residents continue to express concerns over an infestation of scorpions throughout their homes. Last year, the majority of calls were from the Ricardo/Riviera area. So far this year, calls have included Kingsville and Sarita residents.
Extension entomologists believe that weather plays a key role in scorpion numbers. They indicate that long periods without rainfall followed by some rain are believed to contribute to an increase in scorpion activity.
Approximately 90 species of scorpions have been identified in the United States, and 18 of those species live in Texas. The striped bark scorpion is by far the most common in the Lone Star State and the species that is most likely to be encountered by humans.
The basic color varies from yellow to tan in adults. Regardless of the color, two black stripes run the length of the scorpion’s back. The striped bark scorpion can also be identified by the slender pincer-bearing arms and a long, thin tail. The male’s tail is slightly longer than the female’s tail. However, both the male and female have a bulb-like poison gland or stinger on the end of their tail.
The five-segmented tail can be arched over the pest’s back when the scorpion is moving, feeding or threatened. These creatures feed on small insects, spiders, centipedes, other scorpions and earthworms.
The sting from Texas scorpions produce only moderate reactions in most people because the poison has little effect on the nervous system. However, a person who is stung by a scorpion should be watched closely for adverse reactions. If swelling and/or pain persist or breathing difficulties occur, immediate medical attention is necessary. Scorpions with even relatively low poison levels can produce severe reactions in young children and in adults allergic to the toxin.
Scorpions are very prolific, making them extremely difficult to control with insecticides alone. The average litter size of the striped bark scorpion is 31. Not only are they prolific, the striped bark scorpion lives for four or five years. Effective control comes with a strategy that modifies the area surrounding the home and includes the following steps:
- Removal of all trash, logs, stones, bricks and other objects from around the home;
- Keeping the grass mowed near the home and pruning overhanging tree branches (tree branches often provide a path to the roof for scorpions);
- Installation of weather stripping around loose fitting doors and windows;
- Plugging weep holes in brick veneer homes with small squares of wire mesh and also applying an insecticide dust to brick veneer weep holes; and
- Caulking around any cracks in the home.
There are several chemical products available to homeowners for scorpion control, and these products can be obtained wherever lawn and garden supplies are purchased. Insecticides containing active ingredients such as permethrin, cyfluthrin, cypermethrin, lambda-cyhalothrin, deltamethrin, bifenthrin and others are recommended for homeowners.
In addition to the control strategies listed above, applying the insecticide around the foundation of the house and up to one foot above ground level in the exterior walls will aid in control. Also, applying pesticides around doors, windows, eaves and other points of entry will help eliminate entry from this pest. As always, when applying any insecticide follow the directions on the product for dosage, mixing and application methods.