Spiders to Worry About on the Palouse
It is important to remember that spiders kill many, many bugs around the house and lawn that would otherwise be bothering you and your plants. But there are some that live under buildings and outdoors that can hurt you or your family. Brown Recluse, Black Widow, or Hobo spider bites are almost never fatal to healthy adults, but they can be to children and the elderly. If left untreated, a bad bite could possibly lead to death through subsequent infection.
The non-poisonous Giant House Spider (tegeneria gigantea) looks very similar to a hobo spider, (tegeneria agrestis) . The trouble is, they hang out in the same places. If you see one, often you have the other. We prefer to kill them all, and apply a barrier to keep them out of your living spaces. If you search the web for pictures, please note that both spiders around here are a little darker than most internet pictures.
The best treatment option is to spray outside in June or July, killing new juveniles and adult males. Glue traps are effective, if they contain attractant (a blue stripe), but only when fresh and new. We have good control on adults the rest of the summer, but June and July are the best times for treatment. If spiders get very bad inside your home, TLC is licensed and insured to spray indoors as well.
The Hobo spider is not really an aggressive “attacking” spider, but it does often run toward a person, mostly because of bad eyesight; it can’t see more than a foot away. It will NOT hunt you down to bite you, it is more like the black widow and brown recluse in that it will bite when trapped, especially in clothing.
Hobo spiders, like many other venomous creatures, are more likely to incorporate venom in a food-getting bite than in a defensive bite. If you suspect you are bitten, it is incredibly helpful to have the spider for identification. Never throw away a spider you are positive has bit a human. A hobo bite will look like a mosquito bite, though not as itchy. There is a reddened hard area under the skin. If you see a blister begin to form, it is time to see a doctor. The same goes for a brown recluse and black widow, since their venom is similar.
How do you tell for sure that it is a hobo spider?
Unfortunately, unless you are able to examine the very small reproductive structures, you cannot definitively identify a hobo spider. Below are two very Helpful Websites that will help rule out some spiders:
WSU’s excellent Hobo ID article:
THE authority, Darwin K. Vest: