Desert Gardner:

Scorpions don’t have to become a problem

Thursday, Dec. 11, 2008 | midnight

Angela O'Callaghan

When our desert air begins to feel cool, even refreshing to us humans, it can be a problem for some cold-blooded animals that rely on warm weather to keep their metabolism going. That can be a reason we see certain unwelcome visitors who come into our homes during the autumn. One of the least welcome is the scorpion. Even when working outside in the garden, it is possible to encounter one.

These cousins of spiders and mites are not insects. We generally assume that they are denizens of warm climates, but they appear in a wide range of habitats, including the Himalaya Mountains. In Southern Nevada, we are concerned particularly with the desert dwellers.

All true scorpions are venomous, which means that their sting will cause an unpleasant reaction. While it can sometimes even be a life-threatening one, there has not been any reported fatality in the United States from a scorpion sting. Nevertheless, anyone would want to keep these pests out of the home because a sting will be painful and can lead to nausea, numbness, vomiting, difficulty in breathing, even convulsions. (There are some arachnids that can be confused with scorpions, but they are actually beneficial organisms that can be good roach control.)

Urban areas have a problem with a particular variety, called the "bark scorpion," an intruder from Arizona. This is a beige creature that is generally little more than an inch long. In some areas it will grow to 3 inches. This variety is easy to recognize being one of the very few that can climb walls. If they are getting into the house, it is a good idea to take steps to bring the population down to low levels.

First, check to see if there is a problem. Since scorpions glow under ultraviolet light, they can be detected by shining a black light at night, when they are most active.

There are some products labeled for scorpions, but applying those chemicals might be a job best left to professionals. And even so, controlling these pests is not something that can be done solely with insecticides. Like so many other pests, it is most effective to try to control them by limiting their hiding places.

Some of these measures are the same as those we would use to control other pests. Remove trash, boards, stones and other objects like firewood, i.e. anything that would lie on the ground from around the outside of the house. Keep grass around the house mowed low and remove branches that are hanging over the roof. Do not grow groundcovers right next to the house. If garbage cans are stored outside, place them so that they are not directly on the ground. Plug or caulk holes and cracks that could allow entry to the little beasts.

Do not handle a scorpion. University of Arizona experts recommend using tongs to remove one to avoid the venom.

If someone is stung by a scorpion, he or she should receive medical attention immediately. The sting is bad enough, but people have been known to be allergic to the venom.

Angela O’Callaghan is the area specialist in social horticulture for the University of Nevada Cooperative Extension. She can be reached c/o the Home News, 2360 Corporate Circle, Third Floor, Henderson, NV 89074, or TheNews@hbcpub.com.