(Forbes) - Tim Bucher was maybe 10 years old when the tractor broke down acres and acres from the family farmhouse in Healdsburg, Calif. “I was cutting thistles in the fields from early morning until dark,” he recalls. To get home he could either stumble through the fields of the dairy farm—or try to fix the engine. Tinkerer that he was, he opened up the hood, repaired the motor and headed back. There was something deeply satisfying about ­figuring out machinery and working with the soil.