Other Phytophthora species in California’s Native Habitats

Photo by Janell Hillman, Santa Clara Valley Water District

Several first-in-the-USA detections and newly identified species of Phytophthora in both native plant nurseries and restoration areas have occurred in recent years. Many of these Phytophthora species appear to have wide host ranges, capable of causing disease on plants across many families and in many different habitats. The Phytophthoras in Native Habitats Work Group formed to determine steps needed to protect wildlands and assist the restoration industry. The Work Group is now part of the California Oak Mortality Task Force and serves as an “Other Phytophthoras” committee for that group.

Quick Links

General Nursery Accreditation Info

Accreditation to Improve Restoration (AIR) website

Guidelines and Best Management Practices

Sampling and Diagnostic Guide for Soil-borne Phytophthora species on California Native Plants Part 1. Selecting Plants to Sample

Bibliography for Phytophthora species in restoration areas, nurseries and wildlands

Phytophthoras in Native Habitats Work Group

Phytophthora Testing Techniques and Protocols

Calendar of Events

2023 CalPhytos Virtual Annual Meeting, November 8, 2023. See the CalPhytos agenda and the recording of the meeting.

Recordings of the 2022 COMTF Virtual Annual Meeting: See AGENDA for full details and recordings from each day below.

Hear about upcoming events via our newsletter by  signing up for our mailing list.


Are you subscribed to our newsletter? All the most important updates will be emailed directly to you!
Sign up for our mailing list

More information on Phytophthora detections in California native plant nurseries and restoration areas can be found in the resources below:

For more information on Phytophthora species that affect trees, visit the Forest Phytophthoras website.

The Phytophthoras in Native Habitats Work Group

Contact us for more details on how you can be involved with the Work Group.

back to top