Walnut trees and jugalone

**Mad Trapper** · 07-25-2023, 08:44 AM

Not sure if this has been discussed before.

Walnut trees (and related trees butternut, hickory,....) produce a compound that is toxic to other plants and some animals, jugalone.

You should be aware of this if you have them growing near where you garden or plan on planting other things. Also if using the leaves as mulch.

I think this explain the loss of one of my apple trees.

The links have lists of tolerant and intolerant plants.

https://extension.psu.edu/landscapin...oducing-plants

https://gardenerspath.com/plants/lan...lone-toxicity/

https://www.ontario.ca/page/walnut-toxicity

**Broncosfan** · 07-25-2023, 09:22 AM

Originally Posted by Mad Trapper

Not sure if this has been discussed before.

Walnut trees (and related trees butternut, hickory,....) produce a compound that is toxic to other plants and some animals, jugalone.

You should be aware of this if you have them growing near where you garden or plan on planting other things. Also if using the leaves as mulch.

I think this explain the loss of one of my apple trees.

The links have lists of tolerant and intolerant plants.

https://extension.psu.edu/landscapin...oducing-plants

https://gardenerspath.com/plants/lan...lone-toxicity/

https://www.ontario.ca/page/walnut-toxicity

I think that is what caused me to lose an apple tree a few years ago. I've also been told to keep your trees 100' from walnut trees. I planted several trees within 50' of walnuts that are close to my property line. They have done reasonably well but they seem to struggle. They seem to have more bug related problems. I believe I am correct that black walnuts produce the highest levels of the toxin. Eventually I figure these trees will be cut down once the new trees start producing.

**Mad Trapper** · 07-25-2023, 09:53 AM

Originally Posted by Broncosfan

I think that is what caused me to lose an apple tree a few years ago. I've also been told to keep your trees 100' from walnut trees. I planted several trees within 50' of walnuts that are close to my property line. They have done reasonably well but they seem to struggle. They seem to have more bug related problems. I believe I am correct that black walnuts produce the highest levels of the toxin. Eventually I figure these trees will be cut down once the new trees start producing.

Check the lists. Some tress are fine with walnuts, some like apples are easily damaged. Same with vegetables, asparagus peppers tomatoes and potatoes among others are damaged.

I did put down some leaf much that had some butternut leaves mixed in around my tomatoes once before I knew this. The tomatoes were not effected but the leaves had broken down a year first. Not sure how persistent the jugalone is in various walnut tree parts?.