Wood drying or seasoning lumber or timber seasoning in the UK refers to reducing the moisture content of wood prior to its use. The two most important issues are 1) the level of moisture desirable and 2) the means to achieve this. With regard to the level of moisture, for some purposes wood is not dried at all, prior to its use. It is used as is, "green". For other purposes wood must be in equilibrium with the outside air, as in much construction wood. For use indoors, as in furniture, wood must be in equilibrium with the air indoors.
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