The emerald ash borer (EAB) is an invasive beetle that infests and kills ash trees. It was first detected in Oregon on June 30, 2022, in Forest Grove, marking its arrival on the West Coast. EAB poses a significant threat to Oregon's ash trees, including the native Oregon ash (Fraxinus latifolia), which is vital for shade, erosion control, pollution filtration and wildlife habitat. EAB can also infest cultivated olive trees and white fringetree (Chionanthus virginicus).
These initiatives provide essential resources and education to landowners and communities, ensuring a coordinated response to this invasive pest.
Efforts to manage EAB in Oregon include removing infested trees to slow its spread, establishing quarantines to prevent the movement of ash materials, releasing biocontrol agents — three species of tiny wasps that parasitize EAB or its eggs — and educating the public on how to identify and report EAB sightings. These measures aim to protect Oregon's urban and natural riparian forests from the devastating impacts of this pest.
Oregon State University has been involved in efforts to slow the spread of the emerald ash borer through its Extension Service. OSU Extension provides resources and educational materials to help landowners and communities identify and manage EAB infestations.
Before EAB was detected in Oregon, OSU Extension educators helped develop the state's EAB response plan, created educational materials and taught about EAB in the Oregon Forest Pest Detector program. After the detection, OSU Extension, in collaboration with the Oregon Department of Agriculture and Oregon Department of Forestry, quickly disseminated essential information and assisted with monitoring efforts.
OSU Extension has developed guides for monitoring ash forests, implementing integrated pest management strategies, and alternative tree species that occupy similar habitats as Oregon ash, including “What to do about emerald ash borer: Recommendations for tree protection in EAB-infested areas.”
OSU Extension also collaborates with the Oregon Department of Forestry and other agencies to conduct early detection surveys that inform quarantines to limit the movement of infested ash materials.
EAB has emerged in the Willamette Valley and is expected to cause over 99% mortality of Oregon ash. Forestland and small farm owners with Oregon ash and streams and rivers on their property will face challenges due to this pest.
In 2024, OSU Forestry and Natural Resources Extension, along with the Oregon Department of Forestry, held workshops and field sessions to educate landowners on EAB detection and response. They also set up EAB traps in Benton, Linn and Polk Counties and provided information at various events.
As a result, 23 landowners and 26 natural resource professionals learned how to detect and respond to EAB, with some volunteering for future efforts. City parks workers are now monitoring 43 acres of parks, and no new EAB detections were found outside the quarantine zone. Outreach and trapping efforts will continue in 2025.
Efforts to manage the emerald ash borer in Oregon help protect the state's ash trees and maintain the health of its forests and urban landscapes. These initiatives provide essential resources and education to landowners and communities, ensuring a coordinated response to this invasive pest.
