Black walnut trees are stately, large trees with pinnate leaves that produce an abundant crop of green (later yellow) fruits. Old trees can grow to 150 feet and 6-8 feet in diameter. The green, unripe husk of this common walnut is a favorite herbal remedy for fungus infections, giardia infections, diarrhea, and worms. Its hard, strong and dark wood is used in furniture and cabinet making, and for the manufacture of musical instruments, among other uses.
The green unripe fruit should be harvested when they are about 1/2 of their full, mature size. One study shows that these are highest in active phenolic compounds (principally juglone) at this stage. Peel the entire hull from around the embryonic nut and immediately immerse them in a menstruum consisting of a blend of 40% ethanol (80 proof vodka will work), 30% vegetable glycerin, and 30% apple cider vinegar. The vinegar slows the enzymatic breakdown of juglone, which is a major active ingredient, providing the highest quality extract with good stability. Commercial black walnut hulls are often black and sometimes mouldy-looking, and should be used only as a last resort. If you can’t find black walnut hulls on a local tree, many natural food stores sell the herb in the form of liquid extracts or tinctures of satisfactory quality.
Use the herb tincture in a dose of 1/2 to 1 teaspoon in a little water, several times a day. I have found it especially useful for relieving the symptoms of diarrhea due to giardia infection. Think of it for Candidiasis, athlete’s foot, and ringworm. Take a bottle along on a trip to countries or areas with questionable sanitation (for instance in some areas of India or South America). Take 1/2 teaspoon in a little water or tea twice daily as a preventative for bacterial infections when traveling.