“What the heck is this?” asks this reader in his submission regarding the long line of worm-like creatures crawling on top of each other in the picture below. “I found them on an outdoor rug in the morning in Northern Virginia. What our reader found on his rug is what is referred to as a ‘fungus gnat snake’. Clearly, this is not an actual snake, but it is a horde of fungus gnat larvae. These are the youngest form of the fungus gnat, which is a species of fly that, like most species of flies, feeds on rotting organic matter, as do their larvae. They can usually be found in compost bins when the matter inside has been left for a significant amount of time to rot.

Fungus gnat larvae will form this ‘snake’ when they migrate, and it is not very uncommon to spot one, so our reader need not worry about this. Fungus gnat larvae are completely harmless to humans and pets. And as long as these guys are not headed into his home he can just ignore the larvae and let them be on their way. If they are headed toward his home, which their presence on the rug seems to suggest, we just recommend gently moving the larvae at the head of the train away from the home – the rest should follow.

That said, if our reader has a garden that has any seedlings or cuttings in them, he might want to redirect them away from that as well, as they can prove to be harmful those kinds of plants. However, if his plants are mature, he has nothing to worry about. Likewise, if he has any bags of soil outside, we recommend he keep those sealed shut, or that he move them inside, as fungus gnat larvae can infest soil mixes. In any case, we really urge him not to harm the larvae, as they are beneficial to the environment, given their efficiency in breaking down decomposing organic materials.

In conclusion, the horde of worms our reader found on a rug outside his home is a fungus gnat snake. These larvae are truly a spectacle, and we thank our reader for the excellent photo and video he provided. They are nothing to be feared, but if they are about to enter his home, he needs only give them a gentle push in another direction! We hope this helps, and we wish our reader the very best!

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