Browse resources Displaying 1 - 2 of 2 resources Photo: Dave Shaw (Cropped from original) Recognizing ash trees in Oregon, Washington and Northern California How to identify our native and common landscaping ash trees, including look-alikes. All ash trees are susceptible to emerald ash borer, an invasive pest first sighted in Oregon in June 2022. David C. Shaw | Jul 2022 | Educational gallery Peer reviewed (Gray level) Photo by Maggie Livesay (Cropped from original) Bigleaf Maple, Acer macrophyllum Use the arrows to the right and left of the photo to navigate through the photos. Then the back arrow to return to the Educational Gallery home page. Jun 2020 | Educational gallery