Pest Education: Spiders
Many species of spiders are common household pests in the United States.
There are 35,000 described species of spiders in the world.
While the spider is actually one of the most beneficial creatures to mankind, its Hollywood inspired reputation as a deadly predator - along with the unsightly appearance of webs in the corner of living rooms and outdoors, make the spider a undesirable house guest to most property owners.
Although all spiders use venom when they bite their prey, the black widow and the brown recluse (not found in California) are the only North American species dangerous to humans.
About The House Spider
The house spider is so much a cosmopolitan, and so widely distributed, that no one is certain of its original homeland. It has been spread by ships, rail and other forms of transport, including its own system of ballooning. Spiderlings spin silk threads and float with the wind (ballooning) until they land on eaves of buildings or in trees and outdoor landscaping. Spiders also are associated with moisture and therefore, are found in basements, crawl spaces and other damp parts of buildings. They can often be found near outdoor night-lights (which can attract flying insects). Most species hide in cracks and darkened areas.
Control of spiders indoors may involve nothing more that vacuuming up the spiders their webs, and egg sacs. Removal of clutter will reduce spider problems, as will caulking around windows and doors.
Spiders often become particularly numerous on exterior surfaces of homes and buildings where eves are exposed to the wind and when they have a food source of flying insects. With an abundant food source, chronic spider problems can result for which there are few good management options except reducing or modifying night lights (which attract flying insects) and applying residual insecticide treatments. The photos on the right show a cellar spider (top) and a house spider (bottom).
Information partially adapted from the University of Kentucky Department of Entomology.