From the Kitsap Sun – subscription required:
A white, powdery fungus attacking the northwest’s maple trees has spread across Kitsap

From Dept. of Environmental and Forest Sciences, University of Washington:
Bigleaf Maple Decline in Western Washington (research study results at link to left)

Primary Goal: Examine the association between biotic and abiotic factors, and bigleaf maple decline.
Outcome: Determining cause of the decline will guide potential mitigation and management options.

Bigleaf maple decline continues to be a scientific mystery
Forest pathologists in Washington have been investigating the decline of bigleaf maple (Acer macrophyllum) in the Pacific Northwest since it emerged in 2010. Recently, Dave Shaw, OSU Extension forest health specialist, has noticed the maple’s decline in Oregon has intensified and hypothesized that it may be attributed to something other than drought, winter weather, canker diseases, squirrel damage or other common culprits. Bigleaf maple decline has been reported throughout the tree’s entire geographic range, including in California, Oregon, Washington and British Columbia……(more at link above)

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