Re: COMPOST--and Black Walnuts
- To: Multiple recipients of list <i*@rt66.com>
- Subject: Re: COMPOST--and Black Walnuts
- From: H* <H*@aol.com>
- Date: Sat, 7 Mar 1998 16:38:03 -0700 (MST)
Lorraine Miller asked:
<< At our February Iris Club meeting we had a speaker who told us that you
should never put walnut leaves in the compost pile. Guess they are supposed
to be toxic to plants. He is a Master Gardener and I suppose he should know.
But I once knew another M. G. in whom I had no faith whatsoever. She had
some weird iteas about some plants. >>
Black Walnuts (Juglans nigra)and the closely related butternut (Juglens
cinera) inhibit growth in most plants that try to grow beneath them. A
chemical called juglone is diffused from the roots into the soil and leaches
out of the fallen bark, leaves and fruit. This chemical has an allopathic
effect, meaning it suppresses growth. Plants differ in their sensitivity to
juglone, even within the same genus. In the absence of any indication that
composting eliminates this allopathic capability, I would not add any Black
Walnut leaves and detritus to a compost pile. For a list of plants which will
survive under these trees, see the article "Under the Black Walnut Tree" in
Horticulture, October, 1986, from which this post was cribbed.
Anner Whitehead, Richmond,VA 23221
Hery Hall henryanner@aol.com
