SOD Blitz training session returns to Dominican

The public was invited to participate in a free training session at Dominican University of California on how to identify Sudden Oak Death (SOD) symptoms and collect samples for testing. The session was April 21 in Room 102 of the Joseph R. Fink Science Center on campus.

The session, which was led by Dr. Matteo Garbelotto, Adjunct Professor in the Department of Environmental Science,BANNER FOR NORS-DUC WEBSITE copy.jpg Policy and Management at the University of California Berkeley, was held in association with the National Ornamentals Research Site at Dominican University of California (NORS-DUC).  This was part of a series of “SOD-Blitzes” held by Dr. Garbelotto throughout the Northern California from mid-April to mid-May.

Dr. Garbelotto trained about 10 participants to identify SOD symptoms; explained the details of the sampling/collection process; and distributed necessary collection materials to participants.  Once the samples are collected, the UC Berkeley diagnostic laboratory, at no charge, will analyze each collected sample through microscopic and DNA analyses to determine the presence or absence of P. ramorum/SOD.

Dr. Garbelotto said Marin remains a hot-spot for SOD. Following a SOD Blitz at Dominican last year, 18 of the 51 samples collected were positive for SOD. This 35% positive rate was the highest in the state. A very large number of the positive samples came from Mill Valley on the slopes of Mount Tamalpais, which not far from where the California SOD infestation presumably started.

 The Garbelotto lab has genotyped all isolates from Marin, in a way similar to human genetic profiling used in legal criminal cases.  Thanks to the presence of a large genetic database at UC Berkeley, the identity and movement of any SOD genotype can be inferred. These analyses will ensure the pathogen strains used at NORS-DUC will be monitored at all times.

Researchers have discovered that Phytophthora ramorum, the pathogen that causes SOD, spreads most often on infected California bay laurel leaves. It is threatening the survival of tanoak and several oak species in California. Currently, SOD has been discovered in 14 coastal California counties from Monterey to Humboldt.

SOD-blitzes inform and educate communities about Sudden Oak Death and get locals involved in detecting the disease, training them to collect samples for testing and data to help produce detailed local maps of disease distribution. Maps then can be used to identify those areas where the infestation may be mild enough to justify proactive management.

 The goal of SOD-Blitz public meetings are:
• Train participants to identify SOD symptoms on California bay laurel and other hosts.
• Explain the details of the sampling/collection process (number of samples, bagging, storing, tagging, distance between sampled trees).
• Explain how to record the sample location (address, GPS, etc.).
• Explain how to fill out the collection form.
• Define collection areas for each participant.
• Distribute necessary materials to participants (forms, bags, markers, GPS units, laminated pictorial identification cards).

Thanks to funding from State and Private Forestry through the U.S. Forest Service, Dr. Garbelotto has organized SOD-Blitzes in the Bay Area to inform and educate community about Sudden Oak Death.  

 NORS-DUC is the first nursery facility in the United States dedicated to the study of diseases of ornamental plants in a simulated nursery setting.  NORS-DUC was being created with a grant from the United States Department of Agriculture through the 2008 Farm Bill.

Scientists from the national and international research community currently are conducting studies at NORS-DUC focused on understanding and controlling Phytophthora ramorum and ramorum blight on nursery stock.

For more information, contact Sarah Gardner, Dominican’s Director of Research and Communications, at (415) 485-3239 or [email protected]. Or log onto the NORS-DUC website at or the SOD-Blitz Announcement page at