Insects and Spiders - native

Fall Webworm Moth (Hyphantria cunea) on Sep 1, 2023

Submitter does not have a specimen

Description of specimen

Info., from multiple people on Nextdoor feel it is a Caterpillar Nest?
I have been told I should report as they are highly invasive, so I wanted to double check. Can anyone take this down and dispose, tree company?

Commentary

Thank you for your report! Yes, that is the web of Fall Webworm caterpillars (Hyphantria cunea). They are a very abundant native moth. Although the webs are unsightly, the caterpillars rarely defoliate trees. Pesticide treatments are not advised, because the caterpillars are protected by their webbing. Affected branches can be cut from the tree and destroyed, if desired. Thanks for your help!

Tom Valente
Sept. 1, 2023, 3:38 a.m.

Remedy

Information on biology and management in Oregon from the Oregon Dept. of Forestry

Resources

Fall Webworm Moth information on iNaturalist

Location

In my backyard, 2 large nests.

Expert Reviewer

Tom Valente
Oregon Department of Agriculture

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