In this March 6, 2018 photo, farmworkers walk through a field of cabbage during harvest outside of Calexico, Calif. For decades, cross-border commuters have picked lettuce, carrots, broccoli, onions, cauliflower and other vegetables that make California's Imperial Valley "America's Salad Bowl" from December through March. As Trump visits the border for the first time as president on Tuesday, March 13, the harvest is a reminder of how little has changed despite heated rhetoric in Washington. (AP Photo/Gregory Bull)