Fixed copper is one of the oldest fungicides and bactericides, used to control a wide range of plant diseases. NATRIA Disease & Fungus Control is a patented, fixed copper fungicide, made by combining a soluble copper fertilizer with a fatty acid. The copper and the fatty acid combine to form a copper salt of the fatty acid, known technically as a true soap. Control many common diseases with this vegetable, fruit and ornamental fungicide. NATRIA Disease & Fungus Control is suited for use indoors and outdoors.