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Black Walnut tree #756334

Asked June 15, 2021, 11:37 AM EDT

For the last 2 years we have seen a greater number of dead limbs and leaves appearing on our tree. I don’t know if it’s a fungus or insect problem. Healthy limbs suddenly look unhealthy and leaves start falling off. I wondering if we can save the tree or should remove it before it effects other trees and plants in the yard?

Mesa County Colorado

Expert Response

Alan,

You need to look at this limbs and see if you see little pin hole sized holes. If so, you have bark or twig beetle. Unfortunately it can spread a canker that there is no cure for called Thousand Canker Disease. https://extension.colostate.edu/topic-areas/insects/thousand-cankers-diseasewalnut-twig-beetle/ With the prolonged drought we are having multiple reports of walnut not doing well. You are my fourth email in 2 days. Winter drought and prolong drought causes stress, as well as the quick change of weather we had in fall impacted these trees and others. Feel free to send photos if you are not sure. If easier my direct email is Susan<personal data hidden>

Sincerely, Susan C. Horticulture Agent

An Ask Extension Expert Replied June 15, 2021, 4:52 PM EDT

Thanks so much for getting back to me today. We went out to check the tree and it looks even worse than yesterday. I’ll try to send some pictures. Thanks again, Alan

Sent from my iPad

On Jun 15, 2021, at 2:52 PM, Ask Extension <<personal data hidden>> wrote:

The Question Asker Replied June 15, 2021, 5:25 PM EDT