Abstract: An apparatus is disclosed to perform a method of tilling the soil on a crop field that: will hold rainwater where it falls, increase the percolation rate of this water into the soil, and provide storage room above and below ground level for this water. The tillage method depends on forming a series of small, flat topped terraces with interconnecting lateral dams. These small, flat topped terraces are sized, laterally spaced, and flat topped so that row crops can easily be planted on top of them. The small, flat topped terraces are generated during a deep soil tillage operation. An apparatus is provided to generate these uniformly spaced, flat topped terraces with lateral dams in a four-step process while traveling in either direction across a sloping crop field. Small supplemental tillage means may advantageously be provided for lateral dam generation under adverse soil conditions.