Hobo Spiders in Oregon
- The hobo spider, Tegenaria agrestis, is a transplanted European spider. While they are thought harmless in Europe, in Oregon they have a reputation for being aggressive and having a bite that causes lesions. They gravitate to areas where people live, and are most often seen in late summer and fall when the males come out in search of mates.
- Many spiders are difficult to identify, and Oregonians often confuse hobos with their close cousins, the giant house spider, which is much more common in Oregon homes. Adult hobo spiders are dark brown, and if measured with their long legs, about the size of a silver dollar. They have oblong, hairy brown abdomens with reddish-brown stripes, but this is best observed with a magnifying glass or microscope.
- Contrary to its reputation, hobo spiders are not aggressive and will not bite unless cornered. The bite of the hobo can cause blistering and lesions that take a long time to heal, although severity of the bite seems to depend on the age and sex of the spider. They are fast runners, but do not climb well. You are most likely to see them scurrying across the kitchen floor or trying to scale the side of your bathtub in the fall and winter. You can also find them around foundations, behind secluded shrubs and tall grass, and in firewood piles.
- Take certain precautions to keep contact with spiders to a minimum and thus avoid any encounters with hobo spiders. Seal any points of entry to your home, such as openings around pipes and wiring conduits. Install good window screens. Vacuum often, and sweep down cobwebs in your home and around the eaves of your house. Keep stacks of old wood away from the house and keep vegetation mowed and trimmed. Wear gloves and long-sleeved shirts when handling firewood or cleaning out storage sheds. It also helps to keep bedding off the floor, and shake out towels and clothing before use.
