Midpen Volunteers Join the Fight Against Sudden Oak Death
Volunteers participate in SOD Blitz Survey 2023 to identify trees infected with the deadly pathogen
“Does this look like Sudden Oak Death to you?” I turned to my hiking partner, John, to get his opinion on the California Bay Laurel leaves we were examining. “It could be,” he replied. “See how the leaf is brown at the tip and has lesions like the photos in our handout.”
On a recent Saturday, we found ourselves in Teague Hill Open Space Preserve, near Woodside, doing our best citizen scientist imitations to help Midpeninsula Regional Open Space District track the incidence and spread of Sudden Oak Death. SOD is killing California coast live oak, black oak, Shreve's oak, canyon live oak, and tanoak trees throughout coastal California and Oregon. The research is urgent because during the last decade, the pathogen has killed more than one million oak and tanoak trees.
Midpen first detected SOD at Long Ridge OSP in 2000, and since then has embarked on an ambitious project to find ways to prevent and treat SOD by identifying resistant trees, preventing infection of heritage trees, and participating in collaborative research.
Earlier that morning we attended a training session with a dozen other volunteers at Midpen’s headquarters in Los Altos where we learned how to identify SOD, gather leaf samples, and use the SODMAP mobile app to determine the longitude and latitude of the infected trees. Coty Sifuentes-Winter, Senior Natural Resources Manager, Arianna Nuri, Forest Ecologist, and DC Burriss, Visitor Services Program Coordinator, gave us tips and words of encouragement.
With packets, forms, and photos in hand, we fanned out to several different preserves and began our detective work. We didn’t have to venture far along the trail to find a Bay Laurel with infected leaves. Following the instructions, we gathered eight leaves, inserted them into an envelope, and noted relevant details. Just beyond the first infected tree we found another one and repeated the process.
We also examined the abundance of tanoak trees in the forest, but didn’t spot the telltale symptoms: blackened petiole and mid vein surrounded by yellow or brown leaf tissue. Bay Laurel trees are often a carrier of SOD and spread it to various types of oak trees. We continued our hike through the preserve and didn’t encounter any other trees with SOD.
Our mission completed, we delivered the samples to Midpen headquarters where they would be sent to UC Berkeley for further analysis by scientists at the Forest Pathology and Mycology Lab under the direction of Dr. Matteo Garbelotto.
As long-time visitors who have enjoyed Midpen preserves, we were grateful for the opportunity to do a small part to keep the environment we love as healthy as possible.
Visit the Midpen volunteer page to learn how you can help.