This U.S. industry comprises establishments primarily engaged in mixing ingredients made elsewhere into fertilizers. Manufacturing nitrogenous fertilizer materials or fertilizer materials from sewage or animal waste and mixing these ingredients into nitrogenous fertilizers--are classified in U.S. Industry 325311, Nitrogenous Fertilizer Manufacturing; and Manufacturing phosphatic fertilizer materials and mixing ingredients into fertilizers--are classified in U.S. Industry 325312, Phosphatic Fertilizer Manufacturing.