Bugs in dead trees

Asked May 1, 2020, 2:30 AM EDT

What can of bugs are this one

Multnomah County Oregon

1 Response


That is a long-horned beetle (family: Cerambycidae). Unfortunately, the resolution of the photo is such that I cannot identify the genus or species. Also an indication of the beetle's size, the tree it was coming from, and photos of the beetle from multiple viewpoints would make further identification easier.

Long-horned beetles have larvae that live in an feed upon wood. Luckily, they preferentially lay their eggs in trees that are stressed, diseased, or damaged, or are recently dead. Because of this, they are considered secondary pests. They
can hasten the death of a tree that is already damaged in some way, but they don’t typically attack and damage otherwise healthy plants. With the exception of one species (which I can rule out based on your photo), they also won't attack dry wood in buildings or furniture either.

The long-horned beetle you found bear some resemblance to two species that can be found in Oregon, Phymatodes grandis and Semanotus litigiosus. Phymatodes grandis feeds on wood of oak trees and Semanotus litigiosus feeds on the wood of various types of conifers including Douglas fir, true firs, hemlocks, and pines.

Here are links to some photos of of these species for comparison...
I'm not sure if either of these is correct though.

If you are still curious about a more specific ID, you could send specimens to us at the OSU Plant Clinic and we could try to figure out more. Here are some instructions for submitting a sample if you would like to do that....