English Walnut Tree Dying Back?

Asked November 6, 2018, 1:58 PM EST

Hi, We have an established English Walnut Tree that has been dying for the last couple of years. Most of the new growth and leaves are on the bottom half of the tree, and the top branches didn’t have leaves this year. I’m not sure if it’s actually dying, or if it didn’t get enough water this summer. It’s competing with a huge maple tree growing over it. Not sure if it’s a sunlight issue? We also have always had woodpeckers on that tree every year for the last 13 years since we’ve lived here. Is there anything we can do to diagnose what’s happening and try to save the tree? Thank you, Amy Olson, Eugene

Lane County Oregon forestry trees and shrubs horticulture

1 Response

Thank you for your question. This is one of those diagnosis issues that is almost impossible on the Internet, and especially without more information and pictures of the leaves, nuts and bark. There are two walnut diseases which cause defoliation, described in this Extension article: https://s3.wp.wsu.edu/uploads/sites/2071/2013/12/Disease-Problems-in-Walnuts.pdf

Walnut trees are also subject to insect infestations, listed here: https://pnwhandbooks.org/insect/nut/walnut

Since one or more of these could be your tree's problem(s), some made more probable due to drought stress, you can take one of two courses. You can gather some leaves and nuts, take closeup photos of the trunk, and visit your county Extension office (https://extension.oregonstate.edu/lane) to ask for staff to examine them and advise. Alternatively, you could hire a licensed arborist to visit your property to examine the tree. It looks like a plant you want to save, so I hope you can find a local resource to save it. Good luck!