(Tarım) Bordeaux mixture is a mixture of copper sulfate (CuSO4) and slaked lime used as a fungicide in vineyards. It is used mainly to control garden, vineyard, nursery and farm infestations of fungi, primarily downy mildew, which can result from infections of Plasmopara viticola. It was invented in the Bordeaux region of France, where it is known locally as Bouillie Bordelaise. This fungicide has been used for over a century and is still used, although the copper can leach out and pollute streams