I have heard that the vines have like a 30 year lifespan before the grape quality declines. When I got here there were no vineyards. Couple years later many of the farm grounds were planted in grapes and much of the uncultivated ranch lands were graped. Now the previously cultivated fields are back to raising broccoli :lol:. Lots of the other ground is too hilly for row crops, not sure what will happen with those.