Introduced Pests Outreach Project
Pest Alert: Sudden Oak Death on the move

The pathogen causing sudden oak death, Phytophthora ramorum, has been found outside the quarantine area in California. In March 2004, two nurseries in southern California, Monrovia Nursery in Azusa, California (Los Angeles County) and Specialty Plants Inc., in San Marcos, California (San Diego County), had Viburnum and Camellia plants that tested positive for P.ramorum. P.ramorum has a broad host range infecting about 50 species in 15 different plant families. The USDA has contacted nurseries and consumers who received plant material as part of their trace forward survey. Over 1200 establishments across the United States have received plant materials from Monrovia including four in the state of Massachusetts. Infected stock has been detected P.ramorum in 102 facilities in fifteen states: California, Alabama, Arkansas, Florida, Washington, Oregon, Texas, Colorado, Georgia, Louisiana, Maryland, North Carolina, New Mexico, Tennessee, and Virginia. Specialty Plants, Inc., a web-based retailer, ships plants all over the country. Two hundred customers in Massachusetts alone received mail order plants from them. New regulations were put in place on April 22 requiring that all nurseries in California shipping out of state must test negative for P.ramorum. For the most up-to-date regulatory information and a listed of regulated hosts visit the USDA, APHIS website:

Sudden oak death surveys will be conducted around the United States. In Massachusetts 25 nurseries will be sampled this year as part of the USDA Cooperative Agricultural Pest Survey. Inspectors from the Massachusetts Department of Agricultural Resources (DAR) will collect samples and plant pathologists from the University of Massachusetts will analyze them. In addition the Massachusetts Department of Conservation and Recreation and the U.S. Forest Service will conduct a survey concentrating on natural areas in Massachusetts.

Nurseries are the first line of defense to prevent this pathogen from becoming established in the Northeast. If the presence of the pathogen can be detected early, we are more likely to minimize losses and limit the spread or prevent establishment of this pathogen. Look for symptoms of Phytophthora infection on known host plants received from California. Photos and descriptions of these symptoms and links to further information on sudden oak death are available at: If you have suspect plants, do not move plants or discard them in the compost pile. Phytophthora can persist in soil and water, and we do not want to be distributing the pathogen outside of the nursery where it may find wild hosts to survive on. Call the DAR at (617) 626-1779 to report suspect plants.

The pest alert is from the Massachusetts Introduced Pests Outreach Project, a collaborative project between the Massachusetts DAR and the UMass Extension Agriculture and Landscape Program aimed at preventing the establishment of new pathogens and pests in Massachusetts. Visit the project website ( for more information on Sudden Oak Death and other emerging pests or to subscribe and unsubscribe for pest alerts.

Massachusetts Department of Agricultural Resources
Massachusetts Introduced Pests Outreach Project is a collaboration between the Massachusetts Dept. of Agricultural Resources and the UMass Extension Agriculture and Landscape Program. This website was made possible, in part, by a Cooperative Agreement from the United States Department of Agriculture's Animal and Plant Health Inspection Service (APHIS). It may not necessarily express APHIS' views.