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National Invasive Species Information Center
U.S. Department of Agriculture
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  3. Terrestrial Pathogens and Diseases
  4. Sudden Oak Death

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

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

1995 (Scianna et al. 2003)

Means of Introduction

Accidental

Impact

Potential loss of hardwood forest and increased potential of forest fire; impact to nursery and landscaping businesses (Scianna et al. 2003)

Sudden oak death - Invasive.org

Symptoms, this leaf was confirmed as positive for P. ramorum by Jenny Davidson.

Credit

Joseph O'Brien USDA, Forest Service

Source
Invasive.org.

Find more images

Spotlights

  • Tracking and Fighting a Tree Killer

    • Nov 16, 2021

    • USDA. ARS. Tellus.

    • Potatoes and oak trees don’t have a lot in common, but there is one thing, and it isn’t good – a fungal-like plant pathogen in the genus Phytophthora. One of the many invasive pathogens contained in this genus, P. infestans, was responsible for the Irish potato famine. Since the mid-1990s, though, Phytophthora has been attacking forest trees along the West Coast, with the pathogen P. ramorum, also known as "sudden oak death" (SOD). SOD was first detected in the San Francisco Bay Area; it has since spread throughout California. In 2001, SOD was discovered in southwest Oregon where it infected tanoaks trees. The discovery led to the formation of an interagency team that included researchers from the Agricultural Research Service (ARS) and Oregon State University (OSU), to develop strategies to mitigate the impacts of SOD.

Distribution / Maps / Survey Status

  • Alien Forest Pest Explorer (AFPE)

    • USDA. FS. Northern Research Station.

    • The Alien Forest Pest Explorer (AFPE) is an interactive web tool which provides detailed spatial data describing pest distributions and host inventory estimates for damaging, non-indigenous forest insect and disease pathogens currently established in the U.S. The database is maintained as a joint effort of Purdue University, the U.S. Forest Service Northern Research Station, and the U.S. Forest Service Forest Health Protection.

  • Early Detection & Distribution Mapping System (EDDMapS) - Sudden Oak Death

    • University of Georgia. Center for Invasive Species and Ecosystem Health.

    • Provides state, county, point and GIS data. Maps can be downloaded and shared.

  • Sudden Oak Death - Maps

    • California Oak Mortality Task Force.

Quarantine

Federally Regulated

  • Domestic Quarantine Notices (Title 7: Agriculture, Part 301) - Phytophthora Ramorum

    • U.S. Government Printing Office. Electronic Code of Federal Regulations.

  • Import Federal Orders

    • USDA. APHIS. Plant Protection and Quarantine.

    • A Federal Order is a legal document issued in response to an emergency when the Administrator of APHIS considers it necessary to take regulatory action to protect agriculture or prevent the entry and establishment into the United States of a pest or disease. Federal Orders are effective immediately and contain the specific regulatory requirements.

Videos

All Resources

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Selected Resources

The section below contains highly relevant resources for this species, organized by source.

Council or Task Force
Partnership
Federal Government
International Government
State and Local Government
Academic
Citations