Up until the scientific farming killed agriculture, everyone used crop rotation, classic in Minnesota was grain with hay, harvest the grain and it acted as a cover crop for the hay. Hay and pasture the next year and add manure. Corn the next year on ground that had nitrogen furnished from the hay, weeds crowded out by hay. Next year was back to grain to use more of nitrogen and hay to add some new. Was a 4 year cycle. Whole field if ground was flat, in strips following the contour if not. First brought in soy beans to supply nitrogen for corn. Every one used oats, field peas, buck wheat, clover, rye grass, and such for cover crops. Now it is all chemical fertilizers and cash crops year after year.
