Thank you for your report! No, this isn't killing your trees. This is the native "Ponderous borer", Trichocnemis spiculatus. They aren't pests or tree-killers. They breed in rotting conifer stumps and logs. You're right, they are in the Longhorned beetle family, our largest representative in Oregon. Thanks for being on the lookout.

Tom Valente
July 23, 2024, 1:05 a.m.