ForesTree - Detail Information

Pest and Disease Information

* Natural Resources Canada Armillaria_mellea

Affected Trees:
Bigleaf Maple, Blue Oak, Black Oak, Douglas-Fir, Giant Sequoia, Incense Cedar, Jeffery Pine, Coulter Pine, Monterey Pine, Bigleaf Maple, Sycamore, Tanoak, Canyon Live Oak, Engelmann Oak, Scrub Oak, Coast Live Oak, Madrone, Ponderosa Pine, Gray Pine, Limber Pine, White Fir, Red Fir, Western Juniper, Bigcone Douglas-Fir and Sugar Pine.

* Complete Image Citations:
- Image #1: Natural Resources Canada

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Armillaria mellea
Oak root fungus


Description of Disease

Armillaria cases reduced terminal growth and general decline in affected plants, As the Armillaria advances dieback of twigs and branches (most apparent in hardwoods) can occur. Crown symptoms include chlorosis of needles, stunted leaves, crown thinning, premature fall coloration (hardwoods), basal resinosis, heavy production of cones and fruits, and attack by bark beetles. As the disease advances honey colored mushrooms may be found at the base of the affected tree. After death there is often a mass of fungal tissue growing between the wood and the bark of the tree, called a hyphal fan.

Information on this Disease

pdf A Field Guide to Insects and Diseases of California Oaks

pdf Diagnosis and Monitoring of Sudden Oak Death

pdf Heart Rots of Red and White Firs

 yellow arrow Armillaria Root Disease

 yellow arrow Armillaria Root Disease, FIDL 78

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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