The sugar maple tree yields autumn foliage, maple syrup and Tennessee whiskey. Wood from the tree is chopped into planks, stacked in piles and burned to form charcoal. Freshly distilled, un-aged whiskey is filtered over the charcoal in a mysterious, but necessary step known as the Lincoln County Process (LCP). By law, a product cannot be called Tennessee whiskey without it. Researchers now say they have some clues as to what the process imparts to the final product.