It is my understanding that the bark from yucca roots is loaded with elements that are good for treatment of osteoarthritis. I can't find any information that tells me how to prepare the bark. Should I dry it and grind it into a powder? How can I use it as a topical poultice? Should I soak it in water or boil it? If boiled, will I loose nutrients or will it help to activate the chemical compounds? How can I make use of the leaves for medicinal purposes?