Insects and Spiders - native

Ponderous Borer (Trichocnemis spiculatus) on Aug 7, 2024

Originally reported as Sawyer Beetles (Monochamus sp.)

Submitter does not have a specimen

Description of specimen

Very large, dark colored beetle with long antenna and wings. Probably about 5-6 inches in length.

Commentary

Thank you for your report! The pictures are kind of dark, but I think that is our native Ponderous borer, Trichocnemis spiculatus. They are not pests. Their grubs live in decaying conifer stumps and logs.

Tom Valente
Aug. 8, 2024, 8:19 a.m.

Location

Solis Apartments on Deschutes Market Road. Outside my back apartment door that backs up to the canal. It was on the concrete porch which is flush with the ground. We have some sort of landscape shavings and then grass.

Expert Reviewer

Tom Valente
Oregon Department of Agriculture

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