Last month, during the busy harvest season, a group of farmers near Monticello drove their tractors, trucks and combines out of their half-harvested fields, and parked them. Dozens of red, green and yellow machines, in a long row along the highway outside of town. It was a tribute to a friend and fellow farmer. Only 31 years old, he recently died of cancer. Photographer Matt Rubel was visiting family in the area at the time. He captured the tribute, in photos and in this essay, which ran in Modern Farmer magazine.