Knowledgebase

black or burned walnut meat #926762

Asked March 25, 2026, 4:31 PM EDT

My father's English walnut tree had walnut meat that was black and/or burned last year. Not many were edible Is there a way to help the tree to prevent this from happening? What could be causing it?

Benton County Oregon

Expert Response

Thanks for contacting ask extension with your question about your dad's English Walnut tree.
  I need more information to help you determine what is causing the blackened nut meat.   
  1. Was the nut meat shriveled? 
  2. Was last year the first time these symptoms occurred?
  3. Were there reddish brown to black spots on the leaves and stems? 
  4. Did catkin buds turn dark brown or black and die?
  5. Did nuts fall prematurely?
  6. How often was the tree watered during the summer? What was the irrigation method?
  7. Were the Husk soft and slimy?  Were they also black?
Sorry for so many questions! This will help to narrow down the possible causes. (insects, disease, environmental) 
Looking forward to your reply.

   
Deb K Replied March 26, 2026, 9:28 PM EDT

Loading ...