WSU Seeks Volunteers for Stream Monitoring Project

WSU Seeks Volunteers for Stream Monitoring Project

Researchers from WSU seek citizen scientists to help monitor streams on the east side of the Cascades for tree harming microbes. They are particularly interested in the microbes that may be affecting western larch populations. Visit their webpage to get involved or find more information!

Sooty bark disease on maples in Seattle

Watch out for Sooty Bark Disease on Maples

Seattle urban forestry professionals are concerned with a disease on maple trees caused by Cryptostroma corticale. The fungus was recovered from several sycamore maples (Acer pseudoplatanus) near Ravenna Boulevard in 2017 and has been confirmed on other trees from many areas around Seattle since. The disease is referred to as ‘sooty bark disease’ because it is characterized by mats of black fungal spores after the bark is shed. Other symptoms of infection can include leaf wilting and branch dieback.

Of particular concern, the fungal spores of Cryptostroma corticale may cause respiratory hazards for those working with infected material. Please review other sources of information for best practices when handling material.

More information available here at



Hosts confirmed by Seattle Parks and Recreation:
  • Sycamore maple (Acer pseudoplatanus )
  • Red maple (Acer rubrum)
  • Bigleaf Maple (Acer macrophyllum
  • Horse chestnut (Aesculus hippocastanum)
Please note, there are many fungi that cause black staining or molds on dead plant tissues. Laboratory diagnostics are needed to confirm if a tree is infected with Cryptostroma corticale.


Feel free to contact us should you have an observation to report or if you’re interested in having a sample tested. You can also share trees of concern at

Share a Tree of Concern

Oregon Ash Conservation

Oregon Ash - Genetic Diversity Conservation

Oregon ash seedlings
Oregon ash (F. latifolia) seedlings growing at Dorena Genetic Resource Center - Photo Credit: R. Sniezko

The Emerald Ash Borer (EAB) threatens Oregon ash (Fraxinus latifolia) with local extinction. Western states such as Oregon are taking precautions and preparing for its arrival. Check out the Readiness and Response Plan for Oregon for more information about the threat.

Researchers from the Dorena Genetic Resource Center in Oregon are looking for additional seed collections from California and Washington. Collection time is expected from mid September through November. Collected seed will be used for gene conservation and possibly for EAB-resistance testing. Contact us to contribute!

Calls to Action

Watch this space!

This area of the website will feature important forest health issues that come up over time. For example, if an exotic insect pest is introduced and found in our region, we will use this space to highlight the issue and the ways that you can help.

Stay tuned!

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