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Plywood is normally defined as an assembly of an odd number of layers of wood joined together by means of an adhesive. The various operations for converting round wood into veneer and finally into plywood are chiefly mechanical. However, there are many areas in which chemicals are involved in substantial quantities. A weight of water equal to the oven dry weight of wood used to manufacture plywood must be removed from the veneer of the forest grown tree before adhesive application to assure cure of the adhesive and to meet the needs of plywood use conditions. A billion pounds of liquid synthetic phenol- and urea-formaldehyde resins are consumed yearly by the plywood industry in the United States. One hundred million pounds of proteinaceous grain flour extender and another one hundred million pounds of ligno-cellulose and clay filler are consumed in plywood manufacture each year. Zero water discharge philosophy is a debatable pollution subject in the plywood industry but its application is practical and reasonable in most cases. Air omission control is receiving considerable attention and presents particular problems with free formaldehyde where urea-formaldehyde resins are utilized. Debarked veneer logs create millions of tons of bark which today is not fully utilized. Using this bark and other wood residues for energy generation is a primary objective of plywood mills to essentially free them of petrochemical requirements for energy. These and other areas are reviewed with reference to eighteen million cubic meters of plywood made in the United States yearly.