On Oct 3 at a community meeting on the UC campus, Dr. Matteo Garbelotto reported the results of this spring’s “SOD Blitz” in the northern East Bay area. Altogether 383 samples of potentially infected Bay Laurel leaves, collected by trained “citizen scientists” in the north Berkeley/Claremont Ave/ upper UC Berkeley campus area, were analyzed by Dr. Garbelotto’s lab. 51 samples tested positive for the SOD pathogen. This level of infection was characterized by Dr. Garbelotto as PERVASIVE --sufficient among other things to cause doubt with respect to the apparently negative samples. (According to Dr. Garbelotto, the validity of a negative finding depends largely on how many nearby trees were also sampled as negative. If it looks like a duck and walks like a duck, unless there is a flock of ducks, it might be a chicken.).
Looking at Garber Park in particular, at least three samples tested positive, two of them from Bay Laurel trees situated in a threatening position with respect to our beautiful stand of heritage oaks.
In view of the experience of Dr. Garbelotto’s lab, the significance of a positive finding among the Bay Laurels is sobering. Once the Sudden Oak Death pathogen is present, it is endemic in the ecosystem. There is no sanitizing methodology. Drawing from the lab’s recent history in heavily infected areas of the south bay, in the next decade the north bay can expect about 55% mortality among our coastal oak, quercus agrifolia, populations. If this or a worse scenario were to play out in Garber Park, the entire character of the park would be altered and much of the heritage quality would be compromised or eliminated. In addition, like the ravaged tan oak forests of Marin County, Garber would present an incredible fire hazard due to the parched remains of toppled oak trees.
The “SOD Blitz” samples test for the presence of the pathogen in Bay Laurels, but the infection of the oaks and the appearance of symptoms among them, follows the infection of Bay Laurels by about two to three years. In Garber Park it appears that we have an opportunity right now to assess the situation, to locate the infected Bay Laurels and consider whatever mitigation alternatives seem appropriate. We have a chance to slow the progress of the disease, perhaps to achieve a stalemate. But both strategy and action are required right now—the window for mitigation is closing, faster perhaps because we are looking for a third consecutive warm and wet year in Claremont Canyon and in the Park. Dr. Garbelotto has seen two previous three-year sequences of warm rain which have produced great and rapid expansions of this water-borne pathogen.
The Garber Park Stewards will be seeking the opinion, experience, and advice of those professionals who have followed and studied the spread of the SOD pathogen, and we will look to the City of Oakland as well as the County of Alameda for policies and practices evolving to address the widespread presence of the pathogen in all the watershed lands of the East Bay ridge. The infection is regional, but remedies and mitigations, if they exist, may well be local and specific. We hope the North Hills neighborhood will join us in our efforts to seek the best next-steps for Garber Park and also, for our own back yards.
For those who wish to hear, first hand, Dr. Garbelottos’s presentation of the results for our area, there is one further community meeting scheduled this fall: Wednesday, November 16, 2011 at 7 PM, at the Dimond Library, 3565 Fruitvale Ave, Oakland, hosted by Friends of Sausal Creek.
Dr. Garbelotto’s Treatment and Mitigation workshops are now scheduled in our area for the following Wednesdays: October 26, November 9, and November 16. Attendance is free but a reservation is required which may be made on line at http://www.matteolab.org. All of the treatment workshops will be conducted at the Portico of Tolman Hall on the UC campus (a map is available on the website). These are outdoor meetings, held between 1 and 3 pm, rain or shine.
For the results, the meeting schedules and previous publications on SOD, please consult http://nature.berkeley.edu/garbelotto/english/index.php. Results for the SOD Blitz 2011 can be viewed at:
http://nature.berkeley.edu/garbelotto/english/sodblitzresults2011.php. In addition, the regional results were set forth in a recent SF Chronicle article: http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2011/10/01/MNG71L9OAK.DTL
At this point, based on the “SOD Blitz” samples taken this past Spring in Garber Park and more broadly in the East Bay North Hills/U C area, the conclusion is PERVASIVE INFECTION. We’ve got it.