Crop yields and some soil properties are influenced by crop sequence due to changes in availability of nutrients and water, soil physical properties, and incidence of diseases, weeds, or insects. Since 1979, a crop rotation study has been conducted to assess the effects of various cropping sequences on crop yield and on the response of corn to nitrogen (N) fertilization. Rotations under study are continuous corn for grain, continuous corn for silage, continuous soybeans, several corn–soybean sequences, with one to three corn crops for every soybean crop; and a corn–corn–oats–alfalfa rotation.