Illinois

This field in central Illinois was mapped two different years--corn stubble in 1997 and soybean stubble in 1998.  The soil patterns are virtually identical.

Kansas

This wheat field was mapped four times at different swath widths and directions: 1) in March when the wheat was coming out of dormancy, 2) in July immediately after harvest, 3) in early October after multiple tillage passes, and 4) in November. As is evident from the maps, although the conductivity values change, the zones delineated do not.

Kansas

Click on these images to enlarge the EC information from 1997 and 2001--an amazing 87% correlation on a field with over 3,000 data points!