Insects and Spiders - native

Ponderous Borer (Trichocnemis spiculatus) on Aug 3, 2026

Description of specimen

Submitter has sample

Moving slow, dying, crawling on our back porch next to a grass field by the woods. About 3 inches long.

Commentary

Avatar of commenter Thank you for your report! This is the "Ponderous borer", the largest beetle in Oregon. They are native. They are not tree killers. Their grubs feed in dead conifer stumps and logs.

Tom Valente
Aug. 5, 2026, 8:12 a.m.

Location

On our back porch.

Expert Reviewer

Avatar of Reviewer

Tom Valente
Oregon Department of Agriculture

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