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Sudden Oak Death

Virtual Oak Health Workshop recordings available

This past April, we hosted a series of talks on the challenges faced by California’s native oak trees and oak woodlands. Prerecorded talks were accessed online, then participants attended a live moderated Q&A session on Zoom that is now also available for viewing. Topics include:

  • Conservation of Oregon white oak and CA black oak woodlands
  • Sudden oak death and other Phytophthora problems in oaks and tanoak
  • Wildfire in tanoak, CA black oak, blue oak, & interior live oak woodlands
  • A new, non-native beetle threat to valley oaks
Read more about the event in a UCANR blog post: Hundreds sign up for online oak woodland workshop
This workshop was originally planned to take place at two field stations. Learn more about these partners below.
Sonoma State University's Fairfield Osborn Preserve:  https://www.cei.sonoma.edu
Hopland Research and Extension Center:  http://hrec.ucanr.edu

This workshop is for oak enthusiasts, landowners, natural resource managers, and foresters. For more information about the content of the workshop visit https://cei.sonoma.edu/oak-health-workshop

Learn more and access videos at:


For more information contact Kerry Wininger, UC Cooperative Extension, 707-888-5616, kwininger@ucanr.edu, or Chris Lee, Cal Fire, 707-726-1254, christopher.lee@fire.ca.gov

SOD Hike with California Native Plant Society -- POSTPONED

Due to COVID-19, this event has been postponed. Check back for a rescheduled date, or email kwininger@ucanr.edu to be notified.

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See what we offered Fall 2019: SOD Info &Training Events

CLICK HERE FOR FULL INFO:  Fall 2019 SOD events flier


SOD Blitz Results Meeting 

Tuesday, November 12, 6-8pm, UCCE Sonoma Office, 133 Aviation Blvd #109, Santa Rosa

REGISTER:  ucanr.edu/2019SODBlitzResultsMeeting


SOD Training Workshops -- ISA CEUs applied for!

1) Monday, November 18, 10am-3pm, UCCE Sonoma Office, 133 Aviation Blvd #109, Santa Rosa

REGISTER:  ucanr.edu/SODTrainingWorkshopSantaRosa


2) Tuesday, November 19, 10am-3pm, Mendocino Coast Botanical Gardens,18220 CA-1, Fort Bragg

REGISTER:  ucanr.edu/SODTrainingWorkshopFortBragg


Questions or need to cancel? Contact Kerry at kwininger@ucanr.edu

Thanks for making the 2019 SOD Blitz a success!

*Check back in Spring for 2021 SOD Blitz dates & locations*

Past information about spring 2019 Blitzes:
Test your trees for free!
Monitor disease spread in a rainy year, be on the lookout for new dangerous strains, and test oaks for SOD with OakSTeP
Things are not "as usual." Come learn to:
  • Identify symptoms of SOD on bay laurel, oaks, and tanoak
  • Collect symptomatic leaves from bay laurel and tanoak to be analyzed at NO COST
  • Make important contributions to science
  • Visit and help your local park or preserve
New this year:
- Leaves will be tested for the new and aggressive EU1 pathogen strain. Already in Oregon
forests, we need to look for it in California to have a chance of eliminating it if found.
- Introducing the OakSTeP program that will provide an easy and affordable way for licensed arborists, tree care specialists, preserve mangers and qualified government workers to test oaks for SOD. Join the OakSTep program for FREE if you register in person during a SOD blitz ($200 value), and get priority for sample processing.
- Thinking of doing something to control SOD, or have done so already? We'll have a questionnaire and important information and tips at the trainings.
- El Fairfield Osborn Preserve blitz es un evento bilingue (Inglés y Español)
Six meetings took place this year in Petaluma, Yorkville (docent-led at SSU'sGalbreath Preserve), Sebastopol, Santa Rosa, Sonoma, and Penngrove (docent-led at SSU's Osborn Preserve) from April 25th - 27th.
The Osborn Preserve blitz in Penngrove was a bilingual event (English & Spanish) / Este es un evento bilingue (Inglés y Español) 
Unless otherwise noted, SOD blitz evens consist of a one-hour training, then you collect leaves at locations of your choice and drop them back at the meeting site that weekend. We drive leaves to UC Berkeley Lab for analysis on Monday. You get results in early fall.
There is no cost for this activity. Hosted by the UC Master Gardener Program of Sonoma County SOD Specialists and the University of California Cooperative Extension, Sonoma County. Funding provided by the USDA Forest Service. 
KRCB News Story -- Gathering Leaves: Sudden Oak Death Research

In collaboration with the University of California and The Center for Environmental Inquiry at Sonoma State University, citizen scientists in Sonoma County are collecting bay laurel leaves to assist in controlling the pathogen responsible for Sudden Oak Death.

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Gathering Leaves (for show)

Published by KRCB North Bay Public Media. Also available at the following link:




Over 2,200 trees were sampled in Sonoma County. See Results here.


Video: SOD in Sonoma County