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Sudden Oak Death Monitoring

Stream monitoring for early detection of invasive Phytophthora species in Western Washington

The Phytophthora stream monitoring program at WSU Puyallup

In this project, we are involved with

  • Gathering baseline data on Phytophthora species present in western WA urban and wildland areas
  • Early detection of invasive Phytophthora species
  • Track the movement of P. ramorum from infested areas
  • Expand on the streams currently being sampled by the WA Dept. of Natural Resources as part of national P. ramorum survey and on nursery surveys by WSDA
  • Continue molecular identification of Phytophthora species and their genetic lineages

2017-2018 Monitoring for Phytophthora in restoration sites in Pierce County, WA
Are Invasive Plant Pathogens Moving into the Puyallup River Watershed?– A presentation from the Puyallup River Science Symposium 12/7/2018

2015 Stream monitoring in the Northern Olympic Peninsula and urban areas

2011 Stream monitoring in Puget Sound

2010 Stream monitoring pilot study


Student Projects

What is Phytophthora?

  • A “water mold” closely related to brown algae and diatoms
  • Pathogen spreads via the movement of infected plants, contaminated soil, aerial and water-borne spores
  • Causes economically important plant diseases such as potato blight and sudden oak death
  • Phytophthora diseases on plants are identified by symptoms, microscopic examination and molecular testing
  • Read more about Phytophthora and other Oomycetes here.
Invasive Phytophthora species
One way to stop the damage an invasive species such as Phytophthora may inflict on an ecosystem is to control or eliminate the species when its populations are still small. Students and other volunteers can help scientists by conducting early detection surveys. Unlike many well-known invasive species, Phytophthoras are microscopic and must be detected by indirect methods, such as baiting with leaves of susceptible plant hosts. Stream monitoring programs have been shown to be an effective approach to detect the spread of P. ramorum and focus eradication efforts to high risk areas, thus reducing the threat this pathogen poses to our landscape and forest ecosystems.

How to get involved

We are looking for volunteer groups, students, or other people who are interested in helping monitor streams in Western Washington for P. ramorum and other Phytophthora species. We need people who can access selected streams and place bait bags or collect water samples at regular intervals and can return these samples to the lab. If you are interested in participating, let us know.




For more information or if you wish to be added to the mailing list, contact Marianne Elliott

Our Cooperators:

US Forest Service Dept. of Agriculture
USDA Forest Service

WA Dept. of Natural Resources
WA Dept. of Natural Resources


USDA is an equal opportunity provider and employer.

Contact: Gary Chastagner, 253-445-4528 | WSU Puyallup Research & Extension Center, 2606 West Pioneer, Puyallup, WA, 98371-4998 USA
Last updated January 2, 2013