A reader from Indiana wrote to us a while ago about some black “worms” she is finding in her house. We think the black worms are in fact black millipedes, so we’ll use that word from now on. The black millipedes (or “nearly black” millipedes, as the reader has it) are in her house, which is why they are a source of concern and frustration. The reader has already tried to get rid of the millipedes, but so far to no avail. The reader asked several questions, but she is most concerned with getting rid of the millipedes (i.e., removing the millipedes from her house), so we’ll focus on this question and touch on her other concerns as we go along.
The reader was curious what she found, so we’ll quickly explain why we think she found millipedes. The reader described what she found as “hard” and said the creatures “curl into a tight circle” when threatened, and both of these are characteristics of millipedes, not worms. Millipedes have exoskeletons, which make them hard, whereas worms are quite soft. (At least this is the case with worms like earthworms. People use the word “worm” very loosely and so some types of “worms” could be hard. Indeed, plenty of people refer to millipedes as worms.) One of the defining characteristics of millipedes is that they coil up when threatened, and this seems to be exactly what the reader is describing. Combining the reader’s physical description with the fact that millipedes are common household pests, we feel reasonably confident she found millipedes. Which of the 12,000 species of millipedes she found we can’t say, but presumably a common house variety, which are often a brown or black color and are about an inch to and inch and a half (2.5 to 4 centimeters) in length. This is all perfectly consistent with the reader’s description of what she found.
The reader described herself as being “plagued” by the millipedes and said that her use of Home Defense (the insecticide) didn’t help, and she further worried that she would be dealing with millipedes year after year, so she is clearly concerned about her situation. Unfortunately, pests are a tricky problem to deal with, but we’ll offer some basic advice on getting rid of millipedes, and then our reader can pursue different options and research the problem further now that she knows she is (likely) dealing with millipedes.
The basic aim of getting rid of a pest is to remove the conditions that gave rise to the pest to begin with. Millipedes wouldn’t go into a house, which is not preferable to the outdoors ceteris paribus, unless they were enticed in for some reason. In the case of millipedes, they are attracted to dark, moist places, which is why they are so often found in dank basements and garages, as we explained in an answer to another reader’s question. (This person also thought he was dealing with worms, so he wrote in to ask about reddish, brown “worms” in the house.) Millipedes also need a food source to survive, and any sort of dead organic matter (rotting leaves, old food, etc.) could draw them inside. If an area of the house has these elements, they must be removed. A dehumidifier can help with moisture levels, and decaying organic matter has to be cleaned up. We realize this is much easier said than done, especially if the millipedes are primarily living and breeding in some tiny nook in the house and fanning out from there, but these things must be taken care of.
Another way to address a pest problem is to make it very difficult for any creatures to get into your house. Our article about how to stop small black worms from getting under your doors might be helpful on this topic. Again, this is much easier said than done, and it sounds so obvious as to be unhelpful, but the simple fact of the matter is that millipedes, worms, and other bugs have to get into your house somehow, and the fewer ways they have to get in, the better off you’ll be. Putting screens on your windows is of course helpful, but people often go much further by doing things like making sure cracks in the foundation of their house are sealed. Doing this is probably of limited use if you already have a serious infestation, but it is good to do in any case, as it can help prevent problems in the future.
As we conclude, we should briefly mention that millipedes are for the most part not harmful. They don’t bite or sting, for instance, which make them a more pleasant house guest than, say, centipedes. About the one thing some millipedes can do is emit a chemical that smells and tastes bad (this is why millipedes smell bad), and these chemicals can irritate a person’s skin. So, if our reader is inclined to pick up what she is finding, she’ll be served well by keeping this millipede defense mechanism in mind and washing her hands after contact. That millipedes aren’t especially harmful is probably of little consolation to our reader, though, and we’re sure she still wants to get rid of them. We wish her the best of luck and hope her problem is solved quickly.
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