This article compares the nitrogen mineralization potential (N) of soils under three tillage treatments (moldboard plowing, chisel plowing, and no-till) and several different crop rotations. The moldboard plow treatment had uniform N mineralization (N) potential 0-15 cm; chisel and no-till had higher N 0-5 cm depth and lower N at 5-10 cm and 10-15 cm depth. All treatments had higher N in the fall than in the spring, but there were no significant differences between tillage methods. Chisel plowing and no-till had significantly higher N than moldboard plowing in the spring sampling.