black Walnut tree

Asked November 5, 2016, 9:29 AM EDT

I have a mature black Walnut tree and for the first time in over 25 years it didn't have any walnuts. neither did my butternut tree produce nuts. do you know why? thank you Jan

Hennepin County Minnesota black walnut tree horticulture

1 Response

According to experts at the University of Missouri, "black walnut trees are sensitive to spring frost injury. Freezing temperatures after the onset of bud break can result in the loss of a tree’s entire nut crop."

Black walnut trees from wild stock tend to fruit heavily one year and lightly or not at all the next (biennial bearing). Squirrels taking nuts from a light crop could also account for crop failure.

Our guess is that unfavorable growing conditions account for the lack of nuts this year. Many observers have also reported few or no acorns.

Learn more here: http://www.centerforagroforestry.org/pubs/walnutNuts.pdf