Insects and Spiders - invasive

Pigeon Horntail (Tremex columba) on Oct 1, 2026

Originally reported as Northern Giant Hornet (Vespa mandarinia)

Description of specimen

Submitter does not have a specimen

It was the largest hornet/wasp I’ve ever seen- the larger than an inch and a half long.

Commentary

Avatar of commenter This is pigeon Tremex, an exotic woodwasp (Tremex columba).Pigeon Tremex larvae feed in hardwood trees. They first showed up in Oregon in 2013 in North Portland, since then they’ve spread out as far as Lake Oswego. They can’t sting and aren't harmful to humans or pets. Their long ovipositor is for depositing eggs under the bark of trees. They are established here and unlikely to be eradicated at this point.

Tom Valente
Oct. 1, 2026, 2:51 p.m.

Resources

Pigeon Horntail information from iNaturalist

Location

I found this hornet when I was clearing some blackberries and vines on my property (4526 sw freeman st). When we looked it up, it appears to be the northern giant hornet.

Expert Reviewer

Avatar of Reviewer

Tom Valente
Oregon Department of Agriculture

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