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.



New Humboldt Co. P. ramorum confirmation just 3 miles from Hoopa tribal land. Read more…

Twelve new P. ramorum finds in Oregon, new Sudden Oak Death Task Force formed. Read more…

SANC nursery program to begin Phase II of its pilot phase. Read more…

It’s SOD Blitz season! Read more in the newsletter and check out the calendar for all the events.

Read the latest newsletter.

Resources on P. tentaculata, recently found in native plant nurseries and restoration sites, can be found on the new CalPhytos.org web page.

New THANQs – FAQ Resource for Tree Health Questions

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

5/11 – San Luis Obispo SOD Blitz; San Luis Obispo County Extension Office

5/12 – Atascadero SOD Blitz; Atascadero

5/13 – Karuk SOD Blitz; Orleans

5/27 – Los Gatos Mountains SOD Blitz; Los Gatos

5/31 – Petaluma SOD Blitz; Petaluma

See the entire events calendar.