System Restoration Musculoskeletal USDA Organic Herbal Supplement Certified Organic by Organic Certifiers We prepare our Wild Yam Extract from the rhizome of Dioscorea villosa vines which are Certified Organically Grown especially for us in their natural forest habitat in eastern Kentucky. To assure optimal extraction of Wild Yam's bioactive compounds, the rhizome is hand-harvested only in autumn, is carefully shade-dried, and is then thoroughly extracted.