A common pest encountered throughout the year is the house spider (Achaeranea tepidariorum). House spiders are usually pale yellow, tan, or gray. They are ½ inch or less in length, are not hairy, and spin webs indoors. Webs are frequently abandoned in sites that do not yield prey and new webs are constructed. In fact, house spiders are often referred to as cobweb spiders because of the high number of empty webs that they leave behind.
Although there are thousands of different species of spiders, there are only 2 in North America that are dangerous to humans: the Brown Recluse and the Black Widow. Fortunately, neither of these is very common in the Chicagoland area.
You may see the following in and around your home.
- jumping spiders
- crab spiders
- wolf spiders
All spiders are capable of inflicting painful bites and some people may have bad reactions.
Female house spiders produce approximately 250 eggs at a time which are placed in a silken sac in the center of the web. Under good conditions, depending on temperature and humidity, several egg sacs may be present in the web at the same time. The eggs will hatch in 7 to 10 days and the spiderlings will migrate to their new locations. They can live for 3 weeks or more without food or water. Consequently, the survival rate of the house spiders is fairly high. Spiders are actually beneficial to our environment. They are predators of most live insects and help to control mosquitoes, flies, gnats, and aphids. This plays an important role in spider control. By reducing the food source, we can reduce the number of spiders.
Since house spiders usually construct their webs in open areas of buildings, the easiest way to manage infestations is by non-chemical methods of spider pest control:
- Regularly sweeping down webs and egg sacs
- Caulking cracks around windows and door frames
- Make sure window screens are properly fitted
In addition, exterior lights attract insects which will attract spiders to feed. You may want to consider replacing mercury vapor lights with sodium vapor lights, which are less attractive to insects. In any case, regular exterior perimeter treatments of spider control can drastically reduce spider infestations. Contact your local office for more information or click here.