Abstract: A process and apparatus are provided for improving the friability of soil. The process involves the upward blasting of compressed gas through nozzles, caused to penetrate the surface of the soil. The apparatus employs a hollow drum mounted upon a framework in manner to rotate about a horizontal axis. The drum has a cylindrical wall which holds a multitude of nozzles, each nozzle having a plurality of upwardly directed apertures. When the nozzles are in a vertically downward position penetrating the soil, a short duration pulse of air is passed through the nozzles.