For the first time in two decades, picket lines are in place at North America’s largest cereal mill. The contract for Kraft workers at Quaker Oats’ plant in Cedar Rapids ran out at 12:01 this morning, putting 170 workers on strike. Painters, machinists, carpenters and others are at odds with the company over weekend pay, layoff language and the transfer of eight union workers. 12-hundred people work at the plant. It’s not known yet if production workers will honor picket lines.