Yew tree health - Ask Extension
I have quite a few Yew trees on my property, mostly in a very mature fir stand.
For the last several years they have been dying off. Is there a proba...
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Yew tree health #871558
Asked June 04, 2024, 3:38 PM EDT
I have quite a few Yew trees on my property, mostly in a very mature fir stand.
For the last several years they have been dying off. Is there a probable cause? Many are heavily shaded, but some with more light have died while others in heavier shade are still healthy.
Also, there are no young seedlings, only old trees.
Thank you.
Clackamas County Oregon
Expert Response
Thank you for your question, Steven. The yew species has several pests, both diseases and insects. Without some photos and/or a lab analysis, we can't diagnose which issue(s) they have. Perhaps you can figure it out after reading these, first on diseases: https://pnwhandbooks.org/plantdisease/host-disease/yew-taxus-spp-needle-blight
and https://pnwhandbooks.org/plantdisease/host-disease/cedar-port-orford-chamaecyparis-lawsoniana-root-rot
The common theme in both of these is water, especially non-draining water. While that is often associated with available sunlight, the content of the soil and slope are important. I don't know anything about your soil situation.
And here is one on a common insect pest: https://hortsense.cahnrs.wsu.edu/fact-sheet/yew-root-weevils/
You'll need to do some sleuthing to see if you find insects. If you can sent photos of the trees--up close to see the needles, as well as the whole tree--we can direct you further. Good luck!
and https://pnwhandbooks.org/plantdisease/host-disease/cedar-port-orford-chamaecyparis-lawsoniana-root-rot
The common theme in both of these is water, especially non-draining water. While that is often associated with available sunlight, the content of the soil and slope are important. I don't know anything about your soil situation.
And here is one on a common insect pest: https://hortsense.cahnrs.wsu.edu/fact-sheet/yew-root-weevils/
You'll need to do some sleuthing to see if you find insects. If you can sent photos of the trees--up close to see the needles, as well as the whole tree--we can direct you further. Good luck!
Thanks for the reply.
From: ask=<personal data hidden> <ask=<personal data hidden>> on behalf of Ask Extension <<personal data hidden>>
Sent: Wednesday, June 5, 2024 10:27 AM
To: Steven Wilkowske <<personal data hidden>>
Subject: Re: Yew tree health (#0141477)
Sent: Wednesday, June 5, 2024 10:27 AM
To: Steven Wilkowske <<personal data hidden>>
Subject: Re: Yew tree health (#0141477)
Welcome. Sorry I couldn't diagnose the problem(s). Perhaps you can take photos and plant samples to the Clackamas County Extension office for Master Gardeners to assess: https://extension.oregonstate.edu/clackamas
