In a central California tomato field a dusty-faced man opened the autodriver of a nuclear-powered truck and inserted a cannery's address card so the truck would know where to deliver its load. Six old men—the tomato pickers—waited for their pay in the truck's lengthening shadow. Most of them smoked or dozed, too tired for talk. Ollie Hollveg, tallest and oldest of the pickers, eyed the heavy-set rancher who sat at the tally table figuring the payroll. For this day's work Ollie expected even less