Invasive Shot Hole Borers
Disease
High Threat
Identification & Biology
Tiny ambrosia beetles that bore into trees and introduce a Fusarium fungus they farm for food. The fungus clogs the tree's vascular system (Fusarium dieback). Entry holes are tiny (< 1mm) but staining on bark is visible.
Current Status
Established in Southern California, spreading. In Orange, LA, Riverside, San Bernardino, San Diego counties.
States affected:
California
What Homeowners Should Do
Look for staining/gumming on bark (sugar volcano on sycamores, dark staining on avocado). Prune and destroy infested branches. Do not chip infested wood - beetles survive in chips. Contact local ISHB detection program.
Identification Photos
Related Threats
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