Emerald Ash Borer found in Oregon - be on the lookout

I’ve been dreading the day. From news articles out today, it seems like Emerald Ash Borers were found in Forest Grove, Oregon, in June. It’s supposedly the first occurrence on the West Coast. The person noticed the D-shaped holes in the bark that the borers make when they emerge from infected trees. I don’t see any observations yet on iNaturalist, but maybe folks can be on the lookout in Oregon and Washington. And keep track of the condition of the Ash trees, too. Here’s one of the news reports: https://www.koin.com/news/environment/invasive-insect-known-to-wipe-out-ash-trees-discovered-in-oregon/.

Thankfully, the Oregon Invasive Species Council developed a Readiness and Response Plan for when the Emerald Ash Borer would show up (https://www.oregoninvasivespeciescouncil.org/eab). Any ideas for an iNaturalist project that would be helpful? It should at least include sightings of the borers, and maybe suspect Ash trees that people could check out and keep track of. Anything else?


My grandparents’ place in New York State had many lovely ashes until I was a teenager. Then the ash borers came through and every large ash died within ten years. Many of them still re-sprout from the roots but I’ve not seen a single adult-sized ash.


Disturbing news; I wonder if parasitoid biocontrol can be approved for this area, as it has in other places?


at least they seem to have got them all quickly, hopefully they will be fine.

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I live in Wisconsin. Here, in about a third of the state all of the ash are dead and the other two thirds the ash are dying. Biocontrol doesn’t seem to do much even in areas it is implemented. Blue Ash seems fairly resistant for whatever reason but that’s our rarest native ash species, the other ash species (White, Green, and Black) are some of our most common and important trees (both ecologically and economically) and they’ll be pretty much entirely removed from the ecosystem within the next few years.

I hate to say it but the slogan “Kiss Your Ash Goodbye” from a decade or so ago holds true unless we can find a good way to get rid of them.

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Not for long.

The infestation was found in a well-frequented area, simply because someone knew what they were looking at. Its likely that there are other EAB infestations in trees that are harder to reach and detect, or have gone so far unnoticed.

This is bad news for our Oregon ash trees and for the health of the Willamette river and other river ecosystems where ash plays a role in bank stability. Look for sickly ash trees, those distinctive D-shaped exit holes and serpentine borer tunnels under split bark.


A recent note in Science says that USDA now estimates the borers have been in the Forest Grove, Oregon, area for maybe five years! That’s so much time for populations to grow and expand. Appreciate your ash trees now and keep a good lookout. And maybe it would be good to focus some observations on all the other organisms living in Ash-dominated places.

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