Therefore, some sensitive plants may tolerate the amount of juglone present in the soil near a black walnut tree, but may not survive direcly under its canopy. Also, decaying roots still relase juglone, toxicity can persist for some years after a tree is removed. The above information is described in more detail in Purdue's Black Walnut Toxicity Publicaton HO-193 . The information given herein is supplied with the understanding that no discrimination is intended and no endorsement by the Purdue University Cooperative Extension Service is implied. Any person using products listed assumes full responsibility for their use in accordance with current direction of the manufacturer.
Information listed is valid only for the state of Indiana.
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