Tree Diseases

We are very fortunate to be in the redwood region, as redwood trees are remarkably disease resistant. Unfortunately, that is not the case for every tree in the Central Coast. Sudden Oak Death (Phytophthora ramorum) is prevalent and has had damaging to devastating effects on our tanoak and oak stands. Pitch Canker (Phytophthora ramorum) plagues local pines, especially Monterey Pine. Insects threats, such as the Golden Spotted Oak Borer detected near San Diego last year also offer threats to the health and welfare of our forests.

In this page, we will publish the latest findings and theories about how these diseases are transmitted and how we can mitigate their effects on our lands.

Upcoming Events

October 16, 2014

The calendar now has three new events: Monterey Air Board Prescribed Burn Workshop – October 22, 2014 10:30 am to 1:00 pm Air District Office 24580 Silver Cloud Court Monterey, CA 93940 Exotic Phytophthora Sepcies in Native Plant Nurseries, Restoration Plantings and Wildlands – December 2, 2014 8:30 am-4:30 pm Location: Log Cabin, 1299 Storey Ave, […]

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New Plant Disease Found in California Nurseries Affects Native Plants

October 10, 2014

Phytophthora tentaculata is a plant pathogen that causes root and stalk rot.  It was first isolated in Germany and was thought to be restricted to Europe, but it was found in a Monterey County nursery in 2012 ( and has since been found in nursery stock in Alameda, Butte, Placer and Santa Cruz Counties and […]

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Sudden Oak Death Lecture: How to identify symptoms on bay laurel before it infects your oaks

April 9, 2013

The U. C. Santa Cruz Arboretum will be sponsoring a lecture on Sudden Oak Death and what the local community can do to identify the disease in their area and mitigate its effects in the early stages, while it is primarily on its host plant, the bay laurel. This is a topic that is immediately […]

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Gold Spotted Oak Borer Update

March 11, 2013

The Goldspotted Oak Borer (GSOB) has now been confirmed in 6 trees near Idyllwild in Riverside County.  This pest had previously been confined to San Diego County, where it has killed at least 90,000 oaks.  CalFire believes the pest was transported from San Diego County in infested firewood. The insect is native to eastern Arizona, […]

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