The past few dry winters are now providing a unique opportunity to flatten the Sudden Oak Death (SOD) epidemic curve. You can help protect oak trees by participating in the East Bay SOD Blitz this May 21-23. SOD Blitz participants look for symptoms, take photographs, and collect leaf samples from California bay laurel trees along trails and in home gardens. Those leaf samples and photos help researchers map the distribution of SOD in California.
SOD has killed tens of millions of oaks and tanoaks in California since the mid-1990s. It spreads to healthy oaks via water droplets from other infected plants, most often California bay laurels, which can be infected but are not killed by the disease. Because bay trees usually become infected before nearby oaks do, bays can serve as an early-warning system for the spread of SOD.
Every spring, SOD Blitz surveys are organized in local communities throughout Northern and Central California. Local SOD Blitzes are for people of all ages interested in learning about the ecology of California’s forests and willing to spend a couple of hours in an oak woodland collecting California bay tree leaves for analysis. To find out more about the SOD Blitz, including links to training videos, the date and location of the 2022 SOD Blitz near you, and maps to pick up collecting packets (for the East Bay, in Orinda and at the UC Berkeley West Gate), visit the SOD Blitz website.
Contact Delia Taylor, deliataylor@mac.com, if you have questions.
Why the 2022 SOD Blitzes are so important
- The SOD pathogen (Phytophthora ramorum, a water mold) is exotic and invasive, thus every year its distribution changes and new outbreaks need to be mapped.
- Multiple pathogen strains cause SOD. While the NA1 strain is now naturalized in California oak woodlands, the more aggressive European EU1 strain has been detected in a single California location and is currently under eradication. Any further early detection and eradication of this new strain may save California from a worse SOD outbreak.
- After multiple dry years in a row, the SOD pathogen survives only on a small number of California bay laurels. Finding the bays that are still infected with SOD in 2022 is a unique opportunity to identify bay trees that may be removed to flatten the SOD epidemic curve. This cannot be done in rainy years because too many trees are infected, so 2022 offers a not-to-be-missed opportunity.
For detailed information about the logistics of a SOD Blitz near you, email your local SOD Blitz organizers listed on the SOD Blitz Survey Schedule.
— Delia Taylor, 2022 East Bay SOD Blitz organizer, deliataylor@mac.com
May 2022
