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Name: steve
Status: other
Grade: N/A
Location: MA
Country: N/A
Date: 10/12/2005

I have a Black walnut tree in my yard. I was told that the tree would produce an enzyme that may inhibit growth of my vegetable garden, is this true?

Juglone produced by black walnut trees can inhibit growth of some plants, but other garden plants are reasonably tolerant. The following should be helpful:

Anthony Brach Ph.D.

Dear Steve,

Black walnut produces a compound that inhibits the growth of plants including those in your vegetable garden. The compound is called juglone and is found in all plant parts. One way to reduce the toxicity is to keep fallen leaves away from areas where you want plants to grow.

Jim Tokuhisa

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