Mediterranean Oak Borer (Xyleborus monographus) on Feb 4, 2026

Submitter does not have a specimen
EDRR Status: Local expert notified

Description of specimen

Large oregon white oak tree that appears healthy but had one very large branch clearly dying with no signs of damage. It looks like another large branch was recently removed from the tree and may have been in the same condition.

I did not see the insect, but I believe the symptoms the tree was showing could be characteristic of MOB. I found saw dust in a number of areas near the base of the tree, but it's possible this was just from the cutting of the other large limb. Photos were taken in October 2025 (which is the first time I saw this particular tree) and I haven't seen this tree again since.

Commentary

Hi Erik, thank you for the report this indeed has the correct signs and symptoms. Because the insects are less active outside the trees this time of year I will need to wait until spring/summer to try and collect for a positive ID so I will put this one on my list to check out and report back.

Christine Buhl
Feb. 4, 2026, 5:14 p.m.