F ew foods are more recognizable — or more American — than the cheeseburger. It’s a staple of fast food and backyard barbecues, served in rations to soldiers and on silver platters to presidents. Politicians invoke it as a symbol of abundance, nostalgia, even patriotism. Its parts — beef, cheese, lettuce, tomato, onions, bun — are so familiar they barely register as something grown, cultivated, or hauled.

Americans consume an estimated 50 billion burgers each year. Together, those billions of burgers represent a vast system that spans thousands of miles and millions of immigrant workers, most of whom never appear in the advertising.

To understand just how dependent American agriculture is on immigrant labor, one need only trace the anatomy of a cheeseburger: onions from Idaho, lettuce

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