Several of these were on my potato plants in Washington state, USA. This one about 7mm in length, some were a bit larger. They were moving in an inchworm-like fashion, but only by touch - I don't think they have eyes. isopropanol preserved specimen

This specimen was photographed after placing in isopropyl alcohol, which changed the color (it was almost white while alive) and the shape somewhat.

  • $\begingroup$ This larvae doesn't seem to match the common pests of potatoes. It is possible this larvae has been infected by a fungi and so is distorted in shape and colour. $\endgroup$ Jul 6, 2020 at 3:54
  • $\begingroup$ @SergiiDymchenko — In the future please edit your post rather than putting important information into comments. Not everyone will read comments and they are also ephemeral, so they should only be used to discuss how to improve a post. Thanks! 😊 $\endgroup$
    – tyersome
    Jul 11, 2020 at 4:06

1 Answer 1


One notorious pest of potato plants are cutworms. Unfortunately due to the the discoloration of the species I am not able to identify for sure which species of cutworm it is.

Cutworms attack a wide host of plants (more info here). According to that same website, the main ways to avoid the damage these larvae can cause are to:

Remove all plant residue from soil after harvest or at least two weeks before planting...

... plastic or foil collars fitted around plant stems to cover the bottom 3 inches above the soil line and extending a couple of inches into the soil can prevent larvae severing plants; hand-pick larvae after dark; spread diatomaceous earth around the base of the plants (this creates a sharp barrier that will cut the insects if they try and crawl over it); apply appropriate insecticides to infested areas of garden or field if not growing organically

These larvae come from a large variety of insects so don't associate them too quickly with one insect or another (many websites associate them with moths but that is not always necessarily accurate).

Here's a source that elaborates a bit more on how to treat them plus another source for how to use pesticides in a garden safely (if no other option is convenient).


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