some forms of alternative medicine are centuries old. african herbalists have a long history of using tree bark, roots, grasses, and flowers to make teas to treat disease. Native americans have used plant products to treat such illnesses as high blood pressure and coughs. At first, modern scientists langhed at herbal healers and called their mathods "grandmother's remedies." Today, however, researchers are testing certain elements in plants in for possible teratment of cancer and AIDS.