After the wood has been split or sawn, it must be dried. The drying process can be achieved either naturally in the open air or artificially using kilns. French oak has traditionally been air dried one year for every 10 mm/0.4 in width so that it takes between 18 and 36 months to βseasonβ wood by drying it, in stacks of potential staves, in the open, preferably on a site far from any industrial activity or any other source of pollution. This ties up so much capital that many cooperages have been forced to substitute artificial drying techniques which generally take no more than 12 months.