The Oregon Department of Agriculture (ODA) has reinstated and amended an emerald ash borer (EAB) quarantine in Washington County, prohibiting the movement of tree materials from all ash and white fringe tree plant parts outside the county. The newly adopted temporary quarantine excludes olive trees and is set to expire on November 11, 2023. As data becomes available, ODA will evaluate the need for future quarantines.

This most recent quarantine was amended and replaced the expired quarantine first adopted in June 2022, when ODA first discovered the invasive and destructive EAB in Forest Grove within Washington County.

Due to the continued spread risk, ODA has amended and adopted a new temporary EAB quarantine per Oregon Administrative Rule (OAR 603-052-1070), limiting the movement of ash and white fringe tree materials from Washington County.

The quarantine restricts the movement of several tree materials, including but not limited to logs, green lumber, nursery stock, scion wood, bud wood, chips larger than 1 inch by 1 inch, mulch, stumps, roots, branches, and firewood of hardwood species.

The purpose of the quarantine is to slow the spread of the invasive and destructive EAB.

A D V E R T I S E M E N T

A D V E R T I S E M E N T

Researchers consider the half-inch green, shiny beetle North America’s most destructive forest pest, killing hundreds of millions of ash trees nationwide.

So far, the state has only detected EAB within the city limits of Forest Grove.

EAB is native to Asia. Its larvae burrow into the bark of ash trees, causing canopy dieback and, ultimately, tree death. The beetle is often challenging to detect, especially in newly-infested trees.

Signs of infestation include thinning and yellowing leaves, bark splitting, D-shaped holes in the tree bark, and basal shoots.

ODA is establishing several processing and disposal resources to limit the movement of ash and white fringe tree materials within the quarantine area.

To receive more information on EAB with an up-to-date list of resources, or to report a sighting of EAB, please visit the Oregon Invasive Species Council website.


--Ben Fisher

Post Date: 2023-06-18 18:33:22

Last Update: 2023-06-18 18:49:35