Skip to main content Skip to navigation
Washington State University
WSU Puyallup Ornamental Plant Pathology

Phytophthora Stream Monitoring

Early Detection

Western Washington is a “high risk” area for diseases caused by P. ramorum and other Phytophthora species because of favorable environmental conditions and the abundance of susceptible host plants in wildland and urban areas.

The spread of P. ramorum into the landscape could trigger a series of quarantines that would have a significant economic impact on the horticulture and forest products industry.

Stream monitoring programs have been shown to be an effective approach to detect the spread of P. ramorum and focus eradication efforts, thus reducing the threat to our forest ecosystems and economy.

Stream monitoring for Phytophthora

Monitoring in Washington

Our program has collaborated with the Department of Natural Resources (WA DNR) and the Department of Agriculture (WSDA) to monitor for the emergence of Phytophthora ramorum in western Washington since 2003. Initial surveys were conducted widely by WA DNR from 2003-2010. These surveys revealed a few waterways contaminated with P. ramorum and allowed the State to identify the sources, such as adjacent plant nurseries, to prevent the spread into the natural areas.

Since those initial surveys, our program has worked with communities in western Washington to develop a Volunteer Stream Monitoring Program. The aim of the program is to monitor for the emergence of P. ramorum and other potentially invasive Phytophthora species in streams throughout western Washington. Please contact us if you are interested in participating.

Following the findings of P. ramorum in waterways, our program has also conducted research to assess the movement of invasive plant diseases between forests, nurseries, and restoration sites and describe the variation and patterns of spread by using population genetics.

Monitoring Elsewhere

USFS National
Detection Survey

SOD National Detection Survey Locations 2003-2006

Monitoring in

SOD Confirmed Counties in California Map

Surveys in the
United Kingdom

UK Outbreak Map of Phytophthora ramorum locations

Volunteer Stream Monitoring Program

The Volunteer Stream Monitoring Program is a citizen science initiative to engage Washington residents in our research and monitoring efforts.

Anyone is welcome to participate.

Please visit our Volunteer Stream Monitoring Program page or contact us for more information.

2020 Project – This year we are excited to announce we will be sampling on the east side of the Cascades! Click here for more information.

Volunteers in Stream Monitoring Program

More Information

Click on the pictures below for PDF versions of presentations or posters summarizing the methods and results of the Volunteer Stream Monitoring Program and the efforts of the Washington Department of Natural Resources.

You can also learn more about Sudden Oak Death, best management practices, and our Phytophthora research by visiting the Education Program and Research sections of our website.

Additional information pertinent to Washington’s industries is available on the WSDA Website.

WSU Presentation

Stream monitoring Presentation Cover

WSU Summary
Poster (PDF)

Summary SOD Monitoring Poster

WA DNR 2014
Poster (PDF)

WADNR SOD Monitoring Poster 2014

Older WA DNR Posters


WADNR SOD Monitoring Poster 2010


WADNR SOD Monitoring Poster 2009


WADNR SOD Monitoring Poster 2008

Contact Us | WSU Puyallup Research & Extension Center, 2606 West Pioneer, Puyallup, WA, 98371-4998 USA