There are strict criteria in the vineyard for fruit to qualify as old vines Zinfandel. The vines must be at least 50 years old (many are as old as 100) and they must be dry farmed and head trained without the benefit of trellising. These ancient, head-pruned vines tend to produce small quantities of exceptionally concentrated fruit. The grapes are handpicked, crushed and then fermented in stainless steel tanks. After pressing, the wine is pumped into French and American oak barrels for aging, with additional bottle aging before release.