What is Sudden Oak Death?

Sudden Oak Death is a tree disease caused by the plant pathogen Phytophthora ramorum. The disease kills some oak species and has had devastating effects on forests in California and Oregon. Read more about Sudden Oak Death.

Areas of Interest

P. ramorum in Wildlands The information in this section is geared toward land management, forestry and arboriculture professionals, including Best Management Practices.
P. ramorum in Nurseries This section addresses P. ramorum issues critical to nurseries, independent growers, and related plant-care/plant propagation industries, including Nursery Diagnostic Guides.
P. ramorum
in the Urban Interface
Look here for resources that address common homeowner questions, including diagnosing Sudden Oak Death and finding an arborist to work with.


The California Oak Mortality Task Force is a task force under the California Forest Pest Council.



SOD confirmed in Montgomery Woods State Park, Mendocino. Read more…

SOD-related fuel loading evaluated at Jack London State Park. Read more…

SOD Blitz sessions start this month and run through May. Read more…

Become a Sudden Oak Death Citizen Scientist. Join the Cause – Make a Difference!

Resources on P. tentaculata, recently found in native plant nurseries and restoration sites.

New THANQs – FAQ Resource for Tree Health Questions

Read the latest newsletter.

Help stop the spread of forest pests – including Sudden Oak Death – on firewood! Check out the website of the California Firewood Task Force.

Calendar of Events

4/10 – Santa Cruz SOD Blitz Training; UC Santa Cruz Botanic Garden

4/11 – East Bay (Orinda) SOD Blitz Training; Orinda Library Garden Room

4/11 – East Bay (Berkeley) SOD Blitz Training; UC Berkeley campus

4/18 – Napa SOD Blitz Training; UC Cooperative Extension meeting room, Napa

4/28 – Webinar with Jennifer Parke on basic principles of managing pathogens in nursery settings

See the entire events calendar.