Mediterranean Oak Borer (Xyleborus monographus) on Sep 23, 2024

Originally reported as Unknown

Submitter does not have a specimen
EDRR Status: Population assessed

Description of specimen

Suspected Mediterranean Oak Borer. A three-stemmed Oregon white oak was found to have died somewhat suddenly. One of the leaders was completely dead with no leaves. Light brown powdery frass found on trunk of fully dead leader. The two living leaders are in very poor health with browning leaves.

Commentary

I found frass and the dieback pattern matches MOB, I did not find adults however it looks very likely that this is MOB. There is another suspect tree on the other side of the dog park so I have flagged this park for a more thorough inspection along each trail, this season before leaves fully turn.

Christine Buhl
Sept. 23, 2024, 9:50 p.m.