MIKE BENZIGER'S DAY is packed, no time to spare, but as he kicks through the dirt at his family's biodynamic vineyard he can't resist stopping to grab a handful of the rich soil. "Smell that," he says. "Doesn't it smell like beets? This is great soil. It's alive. This is what it's all about." Soil this healthy, Mike says, doesn't just happen. It has been just more than a decade since the Benziger Family Winery in Glen Ellen decided it was tired of growing mediocre grapes, tired of working a chunk of pesticide-laden land so sterile that even the birds...