Emerald Ash Borer found in Newberg
The emerald ash borer has been detected in a parking lot outside Newberg and in Tualatin and Silverton, the Oregon Department of Forestry reported this week.
“This June, the Oregon Department of Agriculture’s Max Ragozzino investigated a report called in to the Oregon Invasive Species Hotline,” ODF reported. “Ragozzino found two trees in a parking lot were heavily infested with EAB. Six others appear to be only lightly infested so far.”
The small, metallic-green emerald ash borers burrow into the bark of ash trees, damaging their canopies and ultimately causing the tree’s death.
The beetle was first discovered in Oregon at a Forest Grove school in 2022 and has since been spreading through the Metro area and Willamatte Valley.
The new detections are within the existing EAB quarantine zone covering the five counties where this pest has been found so far: Clackamas, Marion, Multnomah, Washington and Yamhill.
By order of the Oregon Department of Agriculture, tree material from ash, olive, and white fringetree must remain within quarantined counties, along with firewood from any hardwood tree.
“We have long known that EAB would spread from infested sites to nearby areas, so these new detections are not unexpected,” said Oregon Department of Forestry EAB Support Specialist Matt Mills. “Experience from other states shows that four to five years or so after first being detected EAB spreads from pockets of infested ash trees and becomes much more widespread over an entire county or metropolitan area.”
The ash borer was first reported in Yamhill County last year near the border of Washington County. The adult beetles were discovered during a July 23, 2025, survey by the Yamhill County Soil & Water District about five miles northwest of Yamhill, next to Hawn Creek between Northwest Turner Creek and Northwest Mount Richmond roads.
All three recent reports were made by private individuals who recognized ash trees showing signs of EAB infestation and knew to report them on the invasive species hotline at oregoninvasiveshotline.org.
Homeowners planning to remove ash trees in poor condition are advised to wait until mid-October, when the beetles are no longer flying.
“Pre-emptive removal of such trees will allow them to replant with trees that aren’t vulnerable,” Mills said. “This will start restoring tree canopy and also spreads out the cost of removals. Simply waiting for EAB to start killing trees in your town can become overwhelming in a short period of time and costly.”
Mills said ash trees quickly become brittle and hazardous to climb or work under once they are killed.
“Removal of a dead or rapidly dying ash tree is more dangerous and costly than when it is still alive. That’s why in newly infested areas or areas nearby it’s a best practice to pre-emptively remove any ash trees that are along streets or in parks or yards, and which are in poor condition or planted in the wrong place,” he said.
Mills added that although EABs are spreading naturally through the northern Willamette Valley, people moving firewood more than 10 to 15 miles from an EAB-infested tree risk taking the pest into distant, uninfested areas.
“Firewood being moved is a known way EAB is able to travel farther and spread faster than it could on its own. That is why the Oregon Department of Agriculture doesn’t allow hardwood firewood to be moved from quarantined zones,” he said.
For more information on how to identify ash trees or EAB, what the signs of infestation are, and what can be done in response to an infestation, visit www.OregonEAB.com.
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