ForesTree - Detail Information

Pest and Disease Information

Affected Trees:
Black Oak and Canyon Live Oak.

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Agrilus angelicus
Pacific oak twig girdler


Description of Pest/Symptoms

Pacific oak twig girdler is rated the number one pest of ornamental oaks in Southern California, especially live oaks. Trees weakened by drought are most affected. Adult beetles are brownish copper and lay eggs on twigs of oak trees. The larvae bore into the twig and mine back toward the trunk. After 3 to 6 months, they girdle the twig, causing the terminal foliage to die and turn brown. During the next season it mines toward the trunk and causes large patches of foliage to die.

Information on this Pest

pdf A Field Guide to Insects and Diseases of California Oaks

 yellow arrow Sunset - Oak ailments: prevention and treatme

pdfCalifornia Forest Insect and Disease Training Manual

General Information and Contacts

 yellow arrow CA Agricultural Commissioners

 yellow arrow CA Cooperative Extensions

 yellow arrow Cal Fire - California Forest Improvement Program (CFIP)

 yellow arrow Cal Fire - Contact an Urban Forestry Advisor

 yellow arrow Cal Fire - Forestry Assistance

 yellow arrow Cal Fire - Pest Management

 yellow arrow Cal Fire - Vegetation Management

 yellow arrow California Department of Food and Agriculture

 yellow arrow California National Forests - Offices

 yellow arrow California ReLEAF

 yellow arrow California Urban Forests Council - Regional Councils

 yellow arrow Fire Safe Council - Find a Local Council

 yellow arrow Forest Health and Protection

 yellow arrow Forest Pest Conditions Pacific Southwest Region

 yellow arrow Southern California Mountain Area Safety Taskforce

General Grant Resources

yellow arrow California Oak Mortality Task Force - grants

yellow arrow California ReLEAF Grants

yellow arrow Fire Safe Council Grants Clearing House

yellow arrow Fuels Reduction Program

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