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Don’t cut down that ash tree just yet – Oregon won’t see full effect of emerald ash borer for years

Currently, the emerald ash borer has been found in trees only in Washington County, where a quarantine prohibits moving ash (Fraxinus) or fringe tree (Chionanthus) wood in or out of the area.

Kym Pokorny | Jul 28, 2023 | News story

Which herbicides should I use on poison oak?

Q: I am dealing with poison oak growing in a stand of trees: Douglas firs, big-leaf maple saplings, and others. I have tried manual control and was unsuccessful. What would be the safest topical herbicide to apply to the leaves and stems while minimizing damage to the surrounding trees?

A: View answer | View all featured questions

OSU Extension helps Oregon’s woodland owners manage their land

More than 600 volunteers have been trained through the Master Woodland Manager program.

Alicia Christiansen, Glenn Ahrens | May 2023 | Impact story

Should we treat ash trees for emerald ash borer?

Q: I just read about the emerald ash borer (EAB) appearing in Oregon. We have two large very nice ash trees that we don't want to cut down, no signs of infestation at this time. Would you recommend we go ahead and treat these with the pesticide injection that treats for the borer, just in case?

A: View answer | View all featured questions

Episode 32: Tree School

In this episode, Scott Leavengood visits the 33rd annual Clackamas Tree School to interview Sarah Cameron and Glenn Ahrens about what the event is and why it's so beneficial.

Scott Leavengood, Sarah Cameron, Glenn Ahrens | Apr 2023 | Podcast episode

Episode 31: Master Woodland Managers

In this episode, Lauren Grand invites Susan Watkins, Brett Aldrich, and Tiffany Hopkins on the podcast to discuss the value of participating in the FNR Extension's Master Woodland Manager program.

Lauren Grand, Susan Watkins, Brett Aldrich, Tiffany Hopkins | Mar 2023 | Podcast episode

Five tips for properly planting a conifer tree

When it comes to planting conifers, timing is everything.

Kym Pokorny | Feb 17, 2023 | News story

Triage tips for storm-damaged trees

This set of resources can help you prepare for or respond to storm damage to your trees. The take-home message? Safety first!

Dan Stark, Alexander Gorman, Brad Withrow-Robinson | Feb 2023 | Article

OSU Extension quickly mobilizes to respond to emerald ash borer discovery

Extension curated and disseminated essential information about the devastating pest and assist with initial monitoring efforts to determine how far and fast the insect is spreading in Oregon.

Kym Pokorny | Jan 12, 2023 | News story

Oregon Ash: Insects, Pathogens and Tree Health

Oregon ash grows along the streams and wetlands of western Oregon and Northern California, where it provides important wildlife habitat. But these trees are threatened by the emerald ash borer, an insect pest that...

David C. Shaw, Jay W. Pscheidt, Alexander Gorman | Jan 2023 | Extension Catalog publication Peer reviewed (Orange level)