In Yakima County, Wash., some fruit orchard owners declined on-site testing of workers by health departments at the height of harvest season even as coronavirus infections spiked. In Monterey, Calif., workers at some farms claimed foremen asked them to hide positive diagnoses from other crew members. And in Collier County, Fla., health officials did not begin widespread testing of farmworkers until the end of harvest, at which point the workers had already migrated northward.