A few days ago we received a question through the All About Worms Facebook page about some black worms (or blackish, brownish worms) that have infested the reader’s neighbor’s roof. The reader reports that there are “millions” of black worms around the neighbor’s roof and his house, so we aren’t using the word “infestation” lightly. (We are not being so careful with our use of the word “worm,” however, as the reader’s black worm infestation is probably a black larvae infestation, but we’ll address this in a moment.) The reader’s message is fairly long and quite detailed, but at bottom he wants to know what creature is causing the infestation, and he also wants to know how to get rid of the problem. What black “worms” are behind the infestation, and what can be done to eliminate the infestation?
The reader sent us several good pictures of what he is finding, and we’ve included the best two below. The first shows a collection of the creatures:
And the second is a close-up:
The reader says that he could take similar pictures every morning after he cleans, so the roof infestation next door has clearly affected the surrounding area. However, it is not clear exactly where our reader is finding all the creatures pictured above, as he included this somewhat puzzling line in his email to us: “We are getting worried not because I have spotted them inside the house too.” Nothing that follows clarifies or completes the thought, so he is either finding the creatures outside his house, or he accidentally included the word “not” in his remark, meaning that he is concerned exactly because the infestation has spread to the inside of his house. In either case, the situation is obviously fairly severe – if the reader is finding so many creatures in or near his house every single day, then the roof next door most be overwhelmed.
What can he do about the situation? Unfortunately, there is little advice we can offer because the nature of the infestation is unclear. It isn’t even known exactly what is infested – the reader says the “worms are believed to come from the roof of the house from the neighbors” because it is really old, and we have no basis to offer any alternative, which is why we’ve been talking about the roof all along, but not knowing the origin of the problem complicates any solution we may offer. Eliminating a pest problem is generally about wiping out a generation before they can perpetuate themselves by reproducing. However, if you don’t know where they are coming from, this is obviously much harder to accomplish. You need to find out where they are laying eggs, what they are feeding on, and so on, and these details are tied to the infestation’s ground zero, as it were. In any case, we know that if our reader is dealing with an infestation that involves anything approximating a million worm-like creatures, the situation is way out of control, and professional help should be sought. This is true regardless of what he is finding, which we now turn our attention to.
We said earlier that our reader appeared to be dealing with some sort of larvae, and not a worm, but this is all we can be confident of. Although it is hard to see in the pictures, the creatures appear to have legs and prolegs, which means they are likely some sort of caterpillar, the larval form of moths and butterflies. The reader mentioned that the creatures he is finding have hairs on their bodies that when touched cause skin irritation, and this is certainly consistent with our reader finding some sort of caterpillar. It also possible our reader is finding a type of sawfly larvae, which basically look just like caterpillars, except they have six or more pairs of prolegs, whereas caterpillars have five or fewer pairs. It is difficult to see exactly how many prolegs the creatures pictured above have, and indeed it difficult to even tell if they legs at all.
Despite the detailed message and good pictures we were sent, we unfortunately don’t have a lot of concrete advice we can offer. If the infestation is as large as our reader says it is, it is clearly out of hand and we are not in a position to offer much guidance. It sounds like professional help needs to be called in, and presumably this is the responsibility of the person who owns the house with the infested roof. We also aren’t sure exactly what our reader is finding, but it doesn’t seem to be any sort of worm. Rather, it is appears to be a larvae, which seem to be behind most infestations. It may be a type of caterpillar, but we aren’t certain of this.
We wish our reader the best of luck and hope that his problem reaches a speedy resolution.
All About Worms is always free, always reader-supported. Your tips via CashApp, Venmo, or Paypal are appreciated! Receipts will come from ISIPP Publishing.