For almost a year, presidential candidates have been crisscrossing Iowa, wooing voters in a state that relies on agriculture for about one-third of its economy. But even here, most voters live in cities or suburbs and don’t have a first-hand connection to the farm.

That makes it difficult to get candidates talking about food system issues from school lunches, to crop supports, to water quality. Yet these all fall under the federal agriculture department. If candidates aren’t talking about them in Iowa, it’s possible they’ll be left out of the campaigns entirely.