PestControlBasics
Menu

Identify

Treat

Local

About

Identification

Found a bug? What to do first

Identify the pest before you treat. Many insects that wander indoors are harmless and need nothing more than a vacuum, while a few finds mean an infestation that's worth acting on quickly.[15][17]

The short answer

  • Capture it or take a sharp photo, so it can be identified; for a spider bite, bring the spider to the doctor if possible.[7]
  • Don't reach for a spray or fogger first; read the label and use the lowest-toxicity option that will work, only if you need one.[15]
  • Never handle a bat. If a bat has had contact with a person or pet, contact your county health department about testing it for rabies.[16]
  • If someone was bitten by a black widow or recluse, get medical care and bring the spider if you can.[5][7]

Finds worth acting on quickly

  • Winged termites inside the house almost always mean an infestation that needs treatment. Swarmers from a stump or woodpile outside don't necessarily mean the house is infested.[1][18]
  • Bed bugs: look along mattress seams, box spring joints and bed frames for bugs, eggs, shed skins and dark fecal spots; about 85% are found in or near the bed.[2]
  • German cockroaches: fecal specks, shed skins and egg cases in kitchens and bathrooms point to a breeding population; baits in cracks and crevices work better than sprays.[3]
  • Rodent droppings: ventilate, then soak them with disinfectant and wipe up; never sweep or vacuum them.[4]
  • Carpenter ants: workers often forage in from an outdoor nest, but many winged carpenter ants at windows indoors, or piles of coarse sawdust, point to a nest inside.[13][14]

Usually harmless visitors

  • House centipedes eat other insects; their venom claws are so small they can rarely pierce skin. They point to damp basements and crawl spaces.[8][9]
  • Millipedes wander in from mulch and leaf litter after cool weather or heavy rain and die quickly indoors; some secrete fluids that can irritate skin, so don't handle them.[10][9]
  • Boxelder bugs and multicolored Asian lady beetles come in to overwinter; they don't damage wood, food or clothing but can stain surfaces and smell when crushed.[11][12]
  • Beetles, pillbugs, centipedes and millipedes that crawl out of firewood won't harm you or your home.[17]

Common mix-ups

  • Termite or ant? Termites have straight antennae, a thick waist and equal-length wings; ants have elbowed antennae, a pinched waist and longer front wings.[1]
  • Brown recluse? They have six eyes in pairs; wolf spiders and most other brown spiders have eight. There are no brown recluse populations in California, and recluses are rare outside their native range.[6][7]
  • Many skin conditions, including staph infections, are misdiagnosed as recluse bites.[7]
  • Bed bug or kissing bug? Conenose (kissing) bugs are larger, up to 3/4 inch, less rounded and winged as adults.[2]
  • Black widow or false widow? False black widows are chocolate brown and never have red markings.[5]

Sources

  1. University of Kentucky Entomology, “ENTFACT-604: Termite Control: Answers for Homeowners (revised March 2026).” entomology.mgcafe.uky.edu/ef604 (accessed 2026-10-06)
  2. University of California Statewide IPM Program, “Pest Notes: Bed Bugs, Publication 7454 (May 2013).” ipm.ucanr.edu/legacy_assets/PDF/PESTNOTES/pnbedbugs.pdf (accessed 2026-10-06)
  3. University of California Statewide IPM Program, “Pest Notes: Cockroaches, Publication 7467 (revised December 2019).” ipm.ucanr.edu/legacy_assets/PDF/PESTNOTES/pncockroaches.pdf (accessed 2026-10-06)
  4. Centers for Disease Control and Prevention, “How to Clean Up After Rodents.” www.cdc.gov/healthy-pets/rodent-control/clean-up.html (accessed 2026-10-06)
  5. University of California Statewide IPM Program, “Pest Notes: Widow Spiders and Their Relatives, Publication 74149 (revised March 2017).” ipm.ucanr.edu/legacy_assets/PDF/PESTNOTES/pnblackwidow.pdf (accessed 2026-10-06)
  6. University of Kentucky Entomology, “ENTFACT-631: Brown Recluse Spider.” entomology.mgcafe.uky.edu/ef631 (accessed 2026-10-06)
  7. University of California Statewide IPM Program, “Pest Notes: Brown Recluse and Other Recluse Spiders, Publication 7468 (revised November 2018).” ipm.ucanr.edu/legacy_assets/PDF/PESTNOTES/pnbrownrecluse.pdf (accessed 2026-10-06)
  8. Penn State Extension, “House Centipedes (reviewed 2023).” extension.psu.edu/house-centipedes (accessed 2026-10-06)
  9. University of Kentucky Entomology, “ENTFACT-645: Centipedes & Millipedes in & Around the Home.” entomology.mgcafe.uky.edu/ef645 (accessed 2026-10-06)
  10. Penn State Extension, “Millipedes.” extension.psu.edu/millipedes (accessed 2026-10-06)
  11. University of Kentucky Entomology, “ENTFACT-444: Boxelder Bugs.” entomology.mgcafe.uky.edu/ef444 (accessed 2026-10-06)
  12. University of Kentucky Entomology, “ENTFACT-416: Asian Lady Beetle Infestation of Structures.” entomology.mgcafe.uky.edu/ef416 (accessed 2026-10-06)
  13. University of California Statewide IPM Program, “Pest Notes: Carpenter Ants, Publication 7416 (August 2009).” ipm.ucanr.edu/legacy_assets/PDF/PESTNOTES/pncarpenterants.pdf (accessed 2026-10-06)
  14. Penn State Extension, “Carpenter Ants.” extension.psu.edu/carpenter-ants (accessed 2026-10-06)
  15. National Pesticide Information Center, “Minimizing Pesticide Exposures.” npic.orst.edu/health/minexp.html (accessed 2026-10-06)
  16. University of California Statewide IPM Program, “Bats (Pest Notes, Home and Landscape).” ipm.ucanr.edu/home-and-landscape/bats/ (accessed 2026-10-06)
  17. Iowa State University Extension and Outreach, “Firewood Insects (Yard and Garden, reviewed February 2020).” yardandgarden.extension.iastate.edu/encyclopedia/firewood-insects (accessed 2026-10-06)
  18. University of California Statewide IPM Program, “Subterranean and Other Termites (Pest Notes, Home and Landscape).” ipm.ucanr.edu/home-and-landscape/subterranean-and-other-termites/ (accessed 2026-10-06)

Updated 2026-10-06. Built from sourced records. Spot an error? Tell us.