burning walnut leaves

by Bill
(Sheffield ON)

English Walnut in Autumn

will burning the leaves from walnut trees destroy the juglone?

Comments for burning walnut leaves

Jul 30, 2022

I love these kinds of questions!
by: Jacki Cammidge, Certified Horticulturist

As it turns out, juglone is not even in walnut trees. They actually contain a chemical called 'hydrojuglone'. Juglone is toxic even to walnut trees themselves, so they produce this less toxic version. When hydrojuglone is exposed to air, it turns into juglone.

In spring, the chemical is contained mostly in the leaves that are growing. Some scientists dispute the 'fact' that juglone kills plants. They can't explain it, but there is definitely something going on under walnut trees.

It's not advised to use wood chips of walnut trees, but composting the leaves, as long as there is a time span of around four weeks before spreading it to give bacteria and other creatures time to dispose of the juglone, is fine.

So to answer your question, it appears that juglone is destroyed by contact with air. The problems it causes are mainly in the soil. This leads me to believe that burning the leaves will indeed render them safe.

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