Insects and Spiders - native

Amethyst Cedar Borer (Semanotus amethystinus) on May 22, 2023

Submitter has sample

Description of specimen

We had a cedar tree die. Once cut down, I found the insect and larvae burrowed in several holes in the tree. The insect was alive after several weeks of the cut.

Commentary

Thank you for your report! This is the amethyst cedar borer (Semanotus amethystinus). They are native borers in Western red cedar. They won't attack Douglas-fir. The borers are usually pests in stressed trees and don't attack healthy trees.

Tom Valente
May 23, 2023, 1:24 a.m.

Location

Found in dead cedar tree in forested area on our property. Tree was near roadside.

Expert Reviewer

Tom Valente
Oregon Department of Agriculture

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