In our experience, Black Walnut Hull that is GREEN has about double the amount of juglone, an essential ingredient in the tincture. Dr. Clark Purity Products guarantees unopened bottles of the Black Walnut Hull Tincture to stay green at least until Use By Date. After you open the bottle the tincture will start to turn brown and then black. When black, it contains about half as much Juglone. (Tests on File: Adpen Lab, FL 32224)
*  Note: Unless otherwise noted, this product has not been evaluated by the Food and Drug Administration. Our natural products are not intended to diagnose, treat, cure, or prevent any disease.