Peter and Paul, two Belgian mules belonging to Amish farmer Melvin King of New Holland, Pennsylvania. Melvin was spraying his alfalfa fields with pesticide in order to control the potato leaf hopper.

Amish farmers in Lancaster County, Pennsylvania prefer mules to horses as mules are easy keepers, requiring less food than horses capable of the same amount of work. Almost all the horses and mules in Lancaster County are brought in from the "south" (including Kentucky and southern Indiana) when they're old enough to work and bought at auction rather than farm raised because land is so expensive that it doesn't pay to pasture animals that can't be put to work.