Juglone

[Sam Fleisher]

Some black walnut got mixed in with my cherry shavings that I was going to put around a little sassafras tree to help it through the winter.

A place called the Morton Arboretum has a list of tolerant trees with this above it. And sassafras is on the list. Can anyone confirm? I've had one sassafras die already and had to replant.

"Note that black walnut toxicity due to juglone has not been studied in depth. Much of what is known is based on one study done many decades ago. This means that any list regarding this topic is incomplete and some of the information may be anecdotal."

Thanks

 

[Richard Coers]

Wheat straw would be a perfect insulating product with no ill effect.

 

[Sam Fleisher]

I'd probably have to buy that if I could find one.

You're from the area, is there any turning clubs around?

 

[Brian Gustin]

In my experience, nothing much will grow where Black Walnut is mulching , and indeed can (and has) killed off some raspberry bushes, So I have been much more careful about what I use for mulch around the property, and if I know there's black walnut (green shavings from trees at least) in the shavings, I only use it for mulch in areas where I don't want anything growing (there's still a few stubborn weeds that will poke through, but not too many) so certainly would not use it for mulch on new plantings (Though it doesn't seem to affect more established trees at all) Haven't noticed any real issues with kiln dried black walnut lumber shavings (from planer, table saw, etc) killing stuff off, though, but that's usually mixed in with all the other woods I work with, so not a heavy concentration there. Wood shavings also rob the soil of nitrogen so not good for garden mulch (at least not until it has been well composted) so if you have treees or seedlings that prefer higher nitrogen soil, any type of raw wood shavings as mulch would defeat the purpose.

 

[Sam Fleisher]

In my experience, nothing much will grow where Black Walnut is mulching , and indeed can (and has) killed off some raspberry bushes, So I have been much more careful about what I use for mulch around the property, and if I know there's black walnut (green shavings from trees at least) in the shavings, I only use it for mulch in areas where I don't want anything growing (there's still a few stubborn weeds that will poke through, but not too many) so certainly would not use it for mulch on new plantings (Though it doesn't seem to affect more established trees at all) Haven't noticed any real issues with kiln dried black walnut lumber shavings (from planer, table saw, etc) killing stuff off, though, but that's usually mixed in with all the other woods I work with, so not a heavy concentration there. Wood shavings also rob the soil of nitrogen so not good for garden mulch (at least not until it has been well composted) so if you have treees or seedlings that prefer higher nitrogen soil, any type of raw wood shavings as mulch would defeat the purpose.

It's better to not take a chance I guess. I'll see about prying a bale of straw out of a farmer.

Thanks

 

[Tom Lucas]

Easy and cheap enough to purchase a bale of straw. Why risk the walnut? Leaf mulch would also work (not walnut). I have many black walnuts on my property. Grass struggles mightily to grow under them, even with a lot of sunlight, raking, and mowing. It's pretty obvious looking at the soil under the trees that it is toxic. Cut a few down a while back. Grass growing much better.

 

[R Henrickson]

The *only* thing I have found which grew at all under walnut trees in my yard was daylilies, and even they looked a bit unhappy. I am sensitive to walnut, so I do not use it all.

 

[Rusty Nesmith]

The only thing I have seen grow in walnut shavings is mushrooms. I give my shavings to my neighbor to grow his mushrooms.

 

[Sam Fleisher]

The only thing I have seen grow in walnut shavings is mushrooms. I give my shavings to my neighbor to grow his mushrooms.

Maybe I'll get lucky! I took my walnut and other mixture and spread around the driveway culvert where I can't /don't want to mow.

 

[Gerald Lawrence]

not all plants are sensitive to juglone. I think it is most effective in killing sprouting seedlings. So it can be used as mulch for established plants , but just not worth the trouble.