After 67 years of living and breathing dairy farming in California’s San Joaquin Valley, Scott Magneson cannot, will not, stop.

Every morning before dawn, when the valley fog is still resting on his fields in thick clouds, he checks the barns. Then he starts on the to-do list, which outlasts the day. In another farm tradition, Magneson rarely leaves his land. He can’t remember the last time he and his wife Pat (who does the bookkeeping) took a vacation.