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How to Manage Pests

Quick Tips for Managing Home and Landscape Pests

Spiders banner
Long-bodied cellar spider For more information, see our Pest Notes onSpiders, Hobo Spider, and Brown Recluse and Other Spiders, or contact your local Cooperative Extension office.

Spiders are mostly beneficial because they feed on pest insects. However, many people think that all spiders are dangerous and aggressive. In California, the only spider capable of causing serious injury is the black widow, which generally remains outdoors and out of sight. Spiders seen out in the open during the day are unlikely to bite people. Focus pest management efforts on removing webs and hiding places. Pesticides are not generally recommended.

What to know about spiders:

  • In California, the main spider capable of causing serious injury is the black widow:
  • The poisonous black widow spider is commonly found outdoors, in sheltered, dry, undisturbed areas such as wood piles.
  • Female black widows have shiny black bodies with a red hourglass marking on the underside.
  • Only large female black widows can injure people.
  • Anyone bitten by a black widow spider should remain calm and seek medical advice, or call California's poison control center at 1-800-8-POISON.
  • The brown recluse spider does not live in California.
  • The jaws of most spiders are too small to bite humans.
  • Some other spiders bite when trapped in clothing, but the reaction is no more severe than itching or a bee sting. See the UC Statewide IPM Program Pest Notes for help with identifying these spiders.

Long-bodied cellar spider, black widow spider, and yellow sac spider

To prevent spiders from entering your house, take these steps:

  • Seal home foundation cracks and other access holes
  • Inspect window and door screens for good. seals that keep out spiders and the insects they prey on.
  • Keep areas around home foundations free of clutter.

Manage spiders using these tips:

  • Indoors, regular housecleaning provides adequate spider control.
  • Vacuum up the spider and its web.
  • Prevent clutter buildup that can provide hiding places.
  • Remove spider webs from the exterior of the house with a broom or high pressure hose.
  • Indoors, squash spiders or capture them in a jar and release them outdoors.

When removing spiders, don't overlook the fact that spiders eat a large number and variety of nuisance and pest insects. Spiders also have natural enemies—wasps, other spiders, birds, reptiles and others—that sometimes keep them from becoming too numerous.


Minimize the use of pesticides that pollute our waterways. Use nonchemical alternatives or less toxic pesticide products whenever possible. Read product labels carefully and follow instructions on proper use, storage, and disposal.

What you use in your landscape affects our rivers and oceans!


Statewide IPM Program, Agriculture and Natural Resources, University of California
All contents copyright © 2008 The Regents of the University of California. All rights reserved.

For noncommercial purposes only, any Web site may link directly to this page. FOR ALL OTHER USES or more information, read Legal Notices. Unfortunately, we cannot provide individual solutions to specific pest problems. See How to manage pests, or in the U.S., contact your local Cooperative Extension office for assistance. /QT/spiderscard.html revised: April 14, 2008. Contact webmaster.