Many species of spiders are common pests in the United States.The common household spiders spin webs over lamps, in corners, and in basements creating an unsightly condition but causing no real harm. Remember that every “cobweb” was made by a spider.
Although all spiders have poison with which to kill their prey, the Black Widow and the Brown Recluse are the only North American species consistently dangerous to man. All spiders do inject venom when they bite and although there is generally little danger of complications, it is wise to advise all bite victims to consult their physicians.
Many spiders are associated with moisture, and therefore, are found in basements, crawlspaces and other damp parts of buildings. Others live in warm, dry spaces and can be found in upper corners of rooms, and in attics. Most species hide either in cracks, in darkened areas, or in retreats they construct of silk.
Under most conditions, spiders are considered to be very beneficial because they feed on insects, most notably flies and mosquitoes. Generally, sweeping up the webs, reducing exterior lighting (which attracts flying insects) and sealing gaps and holes around windows, doors and the foundation sill plate will greatly reduce the infiltration of these beneficial arachnids into the home.