Homeowner FAQs
- What is Sudden Oak Death?
- What is SODBusters?
- How is SOD spread?
- How can I confirm that my oak tree has SOD?
- Can I save a tree in my yard that is infected but not dead?
- What will happen if I don't cut down my tree?
- What should be done to a SOD infected tree that was cut down?
- I hate to see this wood go to a landfill: can it be used by the forest products industry?
- Can I use the wood from a SOD infected tree for firewood?
- If I spread the mulch on my land, will it increase the risk that my other trees will become infected?
- Where do I take infected plant material if I can't keep it in my yard?
- If I have a truck, can I bring in SOD infected material on my own to a SODBusters collection site?
- Where can I find the latest regulations pertaining to Phytophthora ramorum?
- What is Sudden Oak Death?
The tree disease commonly referred to as Sudden Oak Death (SOD) is caused by a mold-like microscopic pathogen called Phytophthora ramorum. The pathogen infects some species of native oaks in California, creating cankers under the bark of the trunk. Beetles and decay fungi often further colonize infected trees, which may lead to a rapid weakening of the tree and its death. SOD also infects a number of other species in California's woodlands, though the symptoms on these species are milder, usually only leaf spots and twig dieback and typically are not fatal. For a full list of species that are associated with SOD, go to http://www.suddenoakdeath.org
- What is SODBusters?
The SODBusters project is a two-year research and demonstration project managed by the University of California Division of Agriculture and Natural Resources. The goal of the project is to help facilitate the disposal and utilization of SOD diseased woody materials. The SODBusters Project is currently maintaining collection yards in Marin and Santa Cruz Counties to gather and prepare infected wood for further utilization. Ongoing research conducted as part of the SODBusters Project will help define procedures and recommendations for the removal and transportation of infected material and analyze the quality of the infected wood of host species, identify the best use(s) for the infected wood, and recommend acceptable methods to process and distribute it to appropriate markets. The project is a collaborative effort involving arborists, foresters, scientists, and representatives of county, state and federal agencies that provide the community, business, and regulatory perspectives needed to assure success.
- How is SOD spread?
Research scientists don't yet totally understand all of the mechanisms of spread. Research has shown that P. ramorum can be spread from plant to plant via wind-driven rain, the movement of soil and water, and by moving infected plant parts - especially infected leaves of foliar plant hosts. Researchers are also studying whether P. ramorum can be spread in the air or if some animals may help disperse spores. For the disease to spread the transported P. ramorum must successfully infect an uninfected host plant.
- How can I confirm that my oak tree has SOD?
Because other organisms and injuries can produce symptoms very similar to SOD on oaks, homeowners will not be able to diagnose their trees by themselves with absolute certainty. You can check the web site http://www.suddenoakdeath.org for details on host plants and symptoms, but the only way to confirm a P. ramorum infection is through a laboratory test. Many local arborists, foresters, and tree service companies have undergone training to diagnose SOD. Employees at county Agricultural Commissioner and UC Cooperative Extension offices may be able to assist in sampling, or direct you to trained tree professionals at private companies. Contact the regional SOD coordinator for a list of trained operators.
Bay Area SOD Coordinator: Janice Alexander, ph. 415.499.3041
- Can I save a tree in my yard that is infected but not dead?
There is no way to determine if an individual tree will live or die after contracting SOD. Each tree responds differently to infection, and experience tells us that it is rare for a pathogen to kill all plants it infects. Currently there are no approved chemical treatments to treat infected trees. However there have been some promising results in laboratory trials so there is research to try to identify fungicides that may help reduce infection levels on infected trees. It is not yet clear if any chemical could "save" a tree, or merely extend the time it takes for it to eventually die.
- What will happen if I don't cut down my tree?
Infected trees can remain green and healthy-looking for years, or may quickly succumb to the disease and die in a matter of months. There is no need to cut down an infected tree unless it has become infested with beetles and decay fungi and is rendered structurally unstable. Once a tree has become unstable, it may snap or fall at any time and is a threat to lives and property. For this reason, we recommend that unstable trees be removed, especially if they are near people or buildings.
- What should be done to a SOD infected tree that was cut down? To reduce the risk of disease spread, - it is recommended that as much plant material as possible be left on site, especially leaves and branches less than 4" in diameter. This material can be chipped and used as mulch on site. Material that must be removed should be transported to an approved SOD collection or disposal site within the same county. SOD materials cannot be moved outside of the regulated areas without a Compliance Agreement from the County Agricultural Commissioner.
- I hate to see this wood go to a landfill; can it be used by the forest products industry?
The SODBusters project is coordinating with tree services and green waste facility operators to manage designated SOD collection yards. The first yard opened in Marin County in May of 2003, and an additional yard opened on December 2nd in Santa Cruz County. If you've hired a tree service to remove an infected tree, ask them to take the infected material to the SOD collection yard to ensure its safe processing.
- Can I use the wood from a SOD infected tree for firewood?
Firewood is the easiest way to use the infected wood. The only restriction is that it cannot leave a regulated area. The P. ramorum pathogen is often found in the inner bark so moving wood with bark on it has a high risk of spreading the disease. It is highly recommended that SOD firewood be used close to the site were it was cut. It should not be moved outside of the county.
- If I spread the mulch on my land, will it increase the risk that my other trees will become infected?
If your tree has a SOD infection, the pathogen Phytophthora ramorum is likely already well established in that area. Removing an infected tree does not eliminate the pathogen, and spreading mulch created from infected material will not increase the risk of it spreading to other trees. If possible it is recommended that you use the mulch in an area close to where the tree once stood.
- Where do I take infected plant material if I can't keep it in my yard?
The SODBusters project is coordinating with tree services and green waste facility operators to manage designated collection yards for SOD infected material in Marin and Santa Cruz Counties. The first yard opened in Marin County in May 2003, and an additional yard opened in Santa Cruz County on December 2, 2003. If you've hired a tree service to remove an infected tree, ask them to take the infected material to the SOD collection yard to ensure its safe processing.
- If I have a truck, can I bring in SOD infected material on my own to a SODBusters collection site?
The SODBusters Collection Yard is only open to approved tree service professional. Contact the regional SOD coordinator for a list of trained operators.
Bay Area SOD Coordinator: Janice Alexander, ph. 415.499.3041
- Where can I find the latest regulations pertaining to Phytophthora ramorum?
Please visit http://www.cdfa.ca.gov/phpps/pe/sod_survey/ for the California Department of Food and Agriculture, State SOD regulations and http://www.aphis.usda.gov/ppq/ispm/pramorum/ for the USDA Animal and Plant Health Inspection Service, Federal SOD regulations.