Technical Abstract: The need for additional corn to meet the high demand for bio-fuels in the US will likely lead to more rainfed corn production in the Mid-South. The high degree of soil variability in the area suggests that some fields would be better suited to such a production system than others. Methods are being developed to use precision agriculture data to indicate suitable fields to reduce the risk of crop failure. A field study was conducted at the University of Missouri Delta Research Center Marsh Farm at Portageville to relate information obtained with precision agriculture methods to rainfed corn yields. Initially soil apparent electrical conductivity (ECa) and surface elevation were investigated along with soil mapping units. Yield differences did not correspond well to county soil survey map units. Including relative elevation (RE) in a quadratic equation of ECa provided only a slightly better equation than the ECa terms only. The range of yield values that could be predicted from ECa was not sufficient to adequately describe the observed yields. The study is continuing in 2008 and additional information will be collected.