In the middle of the summer’s worst heat wave, Rodolfo, a 25-year-old from the Western Highlands of Guatemala, stood among a long line of blueberry bushes at Glossy Fruit Farms in Hammonton, New Jersey. A white T-shirt wrapped around his face served a dual purpose: a shield from the intolerably hot sun and a mask against the coronavirus.

At 10 a.m., he had already been in the field for five hours, swiftly and methodically picking the biggest blueberries. After filling five plastic crates about the size of a school lunch tray, he carried them down to a rental truck where supervisors inspected for quality. On a slip of paper they punched a hole for each finished crate. Rodolfo (workers spoke to