Emerald ash borer (EAB) was found in Yamhill County in 2024. The first sighting came from a trap near Gaston, which was initially thought to be a far-flier from the Forest Grove Population.

In 2025, Yamhill SWCD staff worked with landowners to install EAB detection traps on private and District lands. One EAB was caught in northwestern Yamhill County.

There has been an additional new detection in Newberg, confirmed by the Oregon Department of Forestry to be emerald ash borer in early June. It is believed that this insect was accidentally brought in on firewood moved from outside the county. EAB detections are likely to become more frequent and more widespread in Yamhill County over the next couple of years. Firewood is a common vector to spread EAB – to help slow the spread, practice “buy it where you burn it,” and don’t move firewood.

This map shows current EAB sightings, including the new detection site.

What does this mean for Yamhill County? It is time to prepare for EAB infestation and loss of our ash trees NOW!

  • The best way to slow the spread of emerald ash borer (EAB) is simple: don’t move firewood. Transporting firewood is one of the main ways EAB spreads to new areas. If you’re camping, especially outside Yamhill County, buy firewood near your destination. It is illegal to transport wood out of the EAB quarantine area. Even within the county, avoid moving ash wood if you can. Burn it where you buy it!

  • Property owners should begin to prepare for the arrival of emerald ash borer. If you have ash trees, especially if you have a lot of them, consider coming up with an underplanting list. These are trees and shrubs that you can begin to plant now, that will eventually take the place of the ash trees on your property.

  • Another consideration should be identifying and removing any ash trees that could present a hazard. These would be ash trees that are near infrastructure like houses and barns, or even roads or power lines. Once ash trees are dead or dying, they can quickly become more difficult and dangerous to remove. Ash wood dries out quickly and becomes brittle, which poses a risk to any nearby structures if the trees were to fall.

  • The final option for preparation is to treat the trees. This is a good option for properties with a few ash trees that have cultural, emotional, or ecological significance. The costs average around $200 per tree, and treatments must be repeated every 1-3 years, depending on the proximity to a known infestation.

A close-up of an emerald ash borer's face, with the words "Yamhill County's Most Wanted" at the top and a speech bubble that says "One tree at a time... I always finish the job."

If you’re interested in learning more about these options or scheduling a site visit, please reach out to the District’s Riparian Conservationist, Rachel Kato, at [email protected] or 971-241-9479.

Published On: June 26, 2026