Goldspotted Oak Borer
Goldspotted Oak Borer
Goldspotted Oak Borer
University of California
Goldspotted Oak Borer

Report Goldspotted Oak Borer Symptoms

Under a collaborative program, agencies and organizations are working together to determine the distribution, impact and possible prevention methods of tree mortality caused by Goldspotted Oak Borer (GSOB).

Local citizen awareness can help determine the locations of infestations. If you suspect a GSOB infestation in local oak trees, please answer as many of the questions in this survey as possible. Providing digital photos of the tree(s) showing reported symptoms will help us with an initial evaluation. You may upload your photos as indicated at the bottom of this questionnaire.

Requested Photos:

  • One photo of an entire tree
    (so we an see the canopy and get a sense of its overall condition and size)
  • One close-up photo of the leaves
    (to confirm the species of oak)
  • One close-up of the bark surface on the main trunk
    Note: We are especially interested in any insect exit holes on the bark surface.
    • When taking a bark photo, we ask that you place the tip of a pencil, pen or other object near an exit hole to give a sense of scale.
    • GSOB leave a D-shaped exit hole about 3-4 mlimeters (.15 inches) wide (approximately the diameter of an unsharpened #2 pencil lead).

See the GSOB Field Identification Guide for more information.
Note: The scale used for figure #11 on page 3 may be confusing; GSOB exit holes are approximately .15 inches wide, not .25 inches wide).

Contact information is important. After reviewing your report and photos, you will be contacted. Please be assured, your information will be kept private.

Contact Information

Tree Information

If Firewood Near Tree


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