I see these guys crawling around. What are they and are they here to destroy my house and cost me money and waste my time?

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    They are there to teach your kids about insects. I can't tell you how much I learned about the natural world by watching these guys (almost always found outside the house) either scatter when I disturbed a small log, or roll up in defense as I poked them crawling across the front steps. To a 5 year old, poking it and then counting how long it takes to unroll and continue on its way is serious science.
    – Jeff Meden
    Commented Feb 29, 2016 at 18:56
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    @JeffMeden: ...although, technically, these guys aren't insects, but crustaceans that live on land. Which, of course, makes then even more awesome! :) Commented Feb 29, 2016 at 19:12
  • @IlmariKaronen Holy cow I can't believe I didn't know that... You just threw my childhood memories into a new light. Reminds me of this: xkcd.com/1211
    – thanby
    Commented Mar 1, 2016 at 16:49
  • They are not likely to be any problem for your cat. They are land-based crustaceans, thus related to shrimp. Probably tasty, at least to a cat.
    – August
    Commented Mar 1, 2016 at 17:58
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    You should probably view him as a potential early warning - he likes damp, rotting wood. Does that potentially describe any part of the structure of your house, or is it just the big old log lying out in the yard ...
    – brhans
    Commented Mar 1, 2016 at 18:01

3 Answers 3


It's a woodlouse.

Mostly an outdoor bug, generally beneficial, but may bother some plants.

They are generally not a big deal in houses, although not pretty. Wikipedia comments

Woodlice can also invade homes en masse in search of moisture and their presence can indicate dampness problems. They are not generally regarded as a serious household pest as they do not spread disease and do not damage sound wood or structures.

(When I was a kid, we called them potato bugs.)

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    +1 - Do they eat potatoes or are they just supposed to look like a potato? Also I think I had one of these in my living room. Are their feet exceptionally sticky?
    – DMoore
    Commented Feb 29, 2016 at 15:52
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    @DMoore I think we just thought they looked like a baked potato. You mostly find them under rocks and decaying leaves and branches. I have never had them walk across my delicate skin, so I don't know about sticky.
    – bib
    Commented Feb 29, 2016 at 15:55
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    I think I found the source; rotting lumber in my deck. How'd they got in I'm not sure. Perhaps through the door.
    – Rollo R
    Commented Feb 29, 2016 at 19:05
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    @Andrew here's another thing that's called "potato bug" in many places - en.wikipedia.org/wiki/Colorado_potato_beetle
    – Peteris
    Commented Feb 29, 2016 at 20:39
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    @i-CONICA Welcome to the site. The question about stickey was raised by DMoore. If you want to be sure he sees your response, you need to include the @ symblol immediately followed by his name. Then he will get a message you have responded.
    – bib
    Commented Mar 1, 2016 at 12:30

It's a Pill Bug, though around me they're called Potato Bugs...don't eat or swallow them, unless you need protein. They roll up in a ball when you pound on them with your enormously giant finger as you thunderously chuckle at their pain & panic (not everyone likes you). Actually, they're very helpful in most circumstances.

They like soft, moist, "your house is going to fall down" rotting wood. I'm kidding about any imminent collapse, as far as I know. But, they're an indication that something somewhere that shouldn't be getting wet, is starting to decay or has been decaying for a long time.

Maybe this isn't a new house and you're not the original owner. Someone may have hired a guy or gal to just spray poison and did nothing else. These bugs also indicate that you have a tiny if not a mammoth gaping highway hole somewhere, since they've decided to have a party at your place with all of their friends.

Check everything you can on the outside. Like gutters, downspouts, caulk, very short overlaps of plastic siding, light fixtures, doors & windows, hose bibs & the neighboring dog's habits.

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    The first sentence in the second paragraph doesn't make sense.
    – chue x
    Commented Feb 29, 2016 at 15:20
  • Because of the cardboard? I just threw that in since you'll usually find these guys under garage or shed boxes. Do you think I should add that explanation or just remove the cardboard?
    – Iggy
    Commented Feb 29, 2016 at 15:26
  • @chuex Makes sense to me, it's just kind of awkward to read because of the lack of punctuation. Consider: They like soft, moist, "your house is going to fall down" rotting wood or cardboard. Commented Feb 29, 2016 at 16:00
  • @Anthony 's suggestion makes it much better.
    – chue x
    Commented Feb 29, 2016 at 16:50

That insect is a woodlouse also known as "boat builder", "cheesy bob", "pill bug" and many other local names. They seek mould and rotting, damp wood . Not generally harmful and most bug sprays will get rid of them. I even have a cat who likes to eat them (and YES, he is still healthy ! )

  • In rural Michigan they were roly-poly's. Commented Sep 28, 2018 at 17:59

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