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Sudden Oak Death 2015 Monitoring

Community-based stream monitoring for Phytophthora ramorum on the northern Olympic Peninsula, Washington

DSC02296The primary goal of this project is to expand the monitoring of streams in northern Olympic Peninsula region for P. ramorum. In spring 2013 a bait sample positive for P. ramorum was collected from the Dungeness River near Sequim, WA. A second positive bait sample from this site was collected in summer 2013. Further sampling of streams in the area has not yet provided information about the source of inoculum contaminating the Dungeness. The site where the positive sample was found had no apparent direct water connection with a P. ramorum positive nursery and the source of inoculum is unknown.

This project was completed and no P. ramorum was detected! Several species of Phytophthora were found, but most of these are commonly found in streams worldwide. Others may be pathogenic under certain conditions.

Read about the Phytophthora species that were found here.

In this project, we will:

  • Increase the level of monitoring activity in a high risk watershed where the pathogen is exposed to native vegetation.
  • Provide an opportunity to increase public awareness about invasive plant pathogens such as P. ramorum.
  • Genotype P. ramorum collected from waterways to help clarify origin of the inoculum that is spreading into waterways on the Olympic Peninsula.
  • Collect baseline information about Phytophthoras in these streams
  • Identify streams where P. ramorum is not detected.

For more information or to volunteer contact Marianne Elliott (



City of Sequim Surface Water Management page