Green Larvae in Hillsboro Garden

Asked March 17, 2020, 1:16 AM EDT

Hi, Spring is almost here! My son-in-law found a number of larvae in his garden here in Hillsboro today. I have attached a picture of the green colored larvae so you can hopefully identify what creature this is, what it eats, if it is harmful to garden plants, and what are the best methods of getting rid of it. Insecticides are not recommended as a very young child is helping to care for the garden. Thanks!! Allen

Washington County Oregon

1 Response

Thank you for the image. It is a recently molted caterpillar which recently shed its exoskeleton ("skin") in order to grow into the next life stage. It's called the winter cutworm, Noctua pronuba.

These caterpillars feed on greenery in yards and gardens throughout the winter. Further, they feed at night whenever the temperatures are above 40F. Because of that night-time activity, their damage is often blamed on slugs.

"Winter Cutworm: A New Pest in Oregon" [Not really all that new.] has a good description with excellent images for identification. See https://catalog.extension.oregonstate.edu/sites/catalog/files/project/pdf/em9139.pdf