Pau D’Arco [Immune] bark comes from a tree that makes its habitat predominantly in Argentina and Brazil, but which also grows in other tropical areas. The tree grows as tall as 30 meters and is known by the name taheebo. Unlike other trees in the area, pau d’arco does not develop fungus growth. The tree bark was one of the major plants used to promote health and immunity among the Incas, and its use has continued among the Callawaya tribe in South America. Pau d’arco contains a chemical called lapachol, which may provide nutritional support to the immune system. The bark is stripped by hand vertically from the ground up about 6 or 7 feet, leaving enough bark intact to ensure the life of the tree. Nature’s Sunshine’s pau d’arco comes from Brazil. It is available in a variety of forms, including capsules, bulk for tea, liquid extract and soothing, softening lotion.