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Sudden Oak Death

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Sudden oak death -
Scientific Name:
Phytophthora ramorum Werres, de Cock & Man in't Veld (Kliejunas 2010)
Common Name:
Sudden oak death (SOD), ramorum blight, ramorum dieback
Symptoms, this leaf was confirmed as positive for P. ramorum by Jenny Davidson. - Joseph O'Brien USDA, Forest Service


  • USDA. Animal and Plant Health Inspection Service.
    The U.S. Department of Agriculture’s (USDA) Animal and Plant Health Inspection Service (APHIS) is updating domestic regulations for Phytophthora ramorum (P. ramorum), the causal agent of Sudden Oak Death. From 2004 to 2013, APHIS issued a series of Federal Orders to deregulate nurseries where the pathogen has never been found or had not been found recently. Now, APHIS is codifying these Federal Orders with a final rule. APHIS collected and responded to public comments on this rule in 2018. APHIS has determined that updating the domestic regulations to include all Federal Orders issued in recent years will make it easier to find and comply with current restrictions which are necessary to protect the United States from the artificial spread of P. ramorum. This action will go into effect May 20, 2019.
  • USDAAPHISPPQCPHST. Identification Technology Program.

    ITP and the APHIS PPQ S&T Beltsville Lab are pleased to announce the release of IDphy: Molecular and Morphological Identification of Phytopthora Based on the Types, ITP’s first pathogen tool. This website offers PPQ and its partners the most complete, valid, and up-to-date resource for identifying the culturable species of Phytophthora. IDphy includes detailed standard operating procedures for all steps involved in culturing, sequencing, and identifying suspect samples, covering both molecular and morphological methods. Some species of Phytophthora are devastating plant pathogens that have a significant impact on agriculture and natural ecosystems.

Native To:
Unknown; first discovered in the U.S. and Europe at approximately the same time (Scianna et al. 2003)
Date of U.S. Introduction:
Means of Introduction:
Potential loss of hardwood forest and increased potential of forest fire; impact to nursery and landscaping businesses (Scianna et al. 2003)

Distribution/Maps/Survey Status




Selected Resources

The section below contains highly relevant resources for this species, organized by source. Or, to display all related content view all resources for Sudden Oak Death.

Council or Task Force

California Oak Mortality Task Force.


European Network on Invasive Alien Species.
See also: NOBANIS Fact Sheets for invasive alien species of the European region, covering both animals and plants, as well as microorganisms
European and Mediterranean Plant Protection Organization.
Massachusetts Introduced Pests Outreach Project.

National Plant Diagnostic Network.

You can become a more effective First Detector by familiarizing yourself with invasive target pests and pathogens known to exist in the U.S. If you think you have encountered one of the species or disease complexes listed, report its presence.

Nature Conservancy. Don't Move Firewood.
IUCN. Species Survival Commission. Invasive Species Specialist Group.
University of California - Berkeley. Cooperative Extension; USDA. Forest Service.
Ontario's Invading Species Awareness Program (Canada).

North Central Region Pest Management Center.

See also: Pest Alerts for more resources

Federal Government

USDA. Animal and Plant Health Inspection Service.
USDA. APHIS. Plant Protection and Quarantine.

USDA. FS. National Forest Health Monitoring.

International Government

Forestry Commission (United Kingdom). Forest Research.

State and Local Government

Washington Department of Agriculture.

Minnesota Department of Agriculture.

Connecticut Agricultural Experiment Station.

Indiana Department of Natural Resources. Entomology and Plant Pathology.

Georgia Forestry Commission.

North Carolina Department of Agriculture and Consumer Services. Plant Industry Division. Plant Protection Section.


Oregon State University. Extension Service.
A guide for homeowners, small woodland owners, resource managers, and conservation groups to recognize, prevent, and manage Sudden Oak Death.

Michigan State University. Integrated Pest Management Program.

See also: Forecasting Invasion Risks for more factsheets
University of Florida. Institute of Food and Agricultural Sciences Extension.
Electronic Data Information Source Publication #PP197
University of California - Berkeley.
Columbia University. Center for Environmental Research and Conservation.
University of California. Statewide Integrated Pest Management Program.
See also: Pest Notes are peer-reviewed scientific publications about specific pests or pest management topics, directed at California's home and landscape audiences.

University of California - Riverside. Center for Invasive Species Research.

University of Arkansas. Cooperative Extension Service.
See also: Common Disease Problems for more fact sheets