Bugs and spiders in Oregon

What to watch for in Oregon

The western black widow is established in Oregon, so garages, crawl spaces and storage areas are the places to be watchful. A bite from an adult female can cause severe muscle pain and cramps, and the advice is to get medical help right away. The hobo spider is also established and rated Be careful; adult males wander most from August through October. For any worrying bite, call Poison Help at 1-800-222-1222.

Ticks here depend on where you live. The western blacklegged tick is established in parts of the state, mainly west of the Cascades with a pocket in the northeast, and it can spread Lyme disease and anaplasmosis. The Rocky Mountain wood tick is established in eastern Oregon. The brown dog tick is established too but mostly lives indoors with dogs. American dog tick records exist, though it is not known to live in the state.

Through the year

Spring

Pill bugs and rough sowbugs come inside after long rainy periods, and varied carpet beetles gather at windows from late winter into early summer.

Summer

Zebra and bold jumping spiders work the sunny walls and windows, pavement ants swarm around June and July, and European paper wasps are busy outside.

Fall

Asian lady beetles, western conifer seed bugs and brown marmorated stink bugs move in from September into November, just as male giant house spiders and hobo spiders go roaming.

Winter

Warm winter days can bring bold jumping spiders to the windows and wake stink bugs and lady beetles, while house centipedes are noticed more often in winter.