Artifact Size and Lateral Displacement under Tillage: Comments on the Odell and Cowan Experiment

Odell and Cowan's (1987) experimental study largely confirms and extends results obtained by Lewarch and O'Brien (1981) on the effects of tillage on artifact distributions in the plow zone. In contrast to earlier studies, however, they find no relation between artifact size and lateral-displacement distance. The lack of relation between these two variables may be a consequence of defects in experimental design and analysis and should be considered suspect until better controlled data are available.