Due to very long air-drying method and the oak becoming seasoned with sherry, it takes around six years from harvesting a tree to turning it into a cask worthy of maturing one malt whisky. Whereas other distilleries will acquire used casks, The Macallan normally takes a way more holistic approach. https://judahczwrj.weblogco.com/30999685/the-macallan-s-triple-cask-18-diaries