the specification describes preserved solid wood or wood composites including a copper ammonium acetate complex wood preservative and a drying oil . the wood preservative is present in the wood in an amount effective to improve the resistance of the treated wood to at least one type of decomposition , such as decay or insect attack . the drying oil is present in the wood in an effective amount to accomplish at least one useful end , such as reducing the water absorption or thickness swell of the treated wood or increasing its mechanical strength , even in a wood composite made using less binding resin than usual . yet another aspect of the invention is a method of making the treated wood from green wood in solid or flaked form . a copper ammonium acetate complex wood preservative and optionally a drying oil are added to the green wood .