Skip to main content
ARS Home » Pacific West Area » Corvallis, Oregon » Horticultural Crops Research Unit » Research » Publications at this Location » Publication #160227
Title: PHYTOPHTHORA RAMORUM: A GUIDE FOR OREGON NURSERIES

Author
item PARKE, J - OSU
item PSCHEIDT, J - OSU
item Linderman, Robert

Submitted to: Extension Publications
Publication Type: Other
Publication Acceptance Date: 10/1/2003
Publication Date: 12/1/2003
Citation: PARKE, J., PSCHEIDT, J., LINDERMAN, R.G. PHYTOPHTHORA RAMORUM: A GUIDE FOR OREGON NURSERIES. EXTENSION PUBLICATIONS. 2003.

Interpretive Summary: The fungus-like pathogen causing leaf spot and branch dieback of many nursery crops, as well as the 'Sudden Oak Death' syndrome of oaks and other species in forested areas of California and Oregon, is Phytophthora ramorum. This pathogen was detected in wholesale and retail nurseries in California, Oregon, Washington, and British Columbia in 2003. It is a quarantined pathogen, and is considered a Regulatory Incident at the present time. However, the occurrence of the disease in nurseries threatens the nursery industry in Oregon, as well as other states, and the best strategy to address the problem is more research and more information to nurseries that will help in the early detection of the disease, allowing for its eradication. This brochure is an informational document written for Oregon nurseries. It will, hopefully, summarize the known information on the disease at the present time, and thereby elevate the growers' awareness of its epidemiology and control strategies.

Technical Abstract: Phytophthora ramorum, the cause of leaf spot, branch dieback, and tree mortality (Sudden Oak Death) has been detected in wholesale and retail nurseries in California, Oregon, Washington, and British Columbia. This brochure, published by Oregon State University and sponsored by the Oregon Association of Nurseries (OAN), presents information that is needed to control this disease to growers in Oregon nurseries. The guide includes discussions on the history of the discovery of the pathogen and its diseases, the known host plants, the biology of the pathogen, and methods of disease prevention, including exclusion and avoidance, cultural management, protection and suppression with fungicides, and detection and eradication. It will be sent to the membership of the OAN, but will provide guidance to all nurseries threatened by this disease and pathogen.