In past years, PFI cooperators have carried out a variety of tillage comparisons. Ted and Donna Bauer, Audubon, have done several trials of 19- inch versus 38-inch-row soybeans. In 1996, because of planting delays, they custom hired a drill for most of their beans. Ted compared the drill to 19-inch rows that he created himself with a double pass of the planter. This was a “proof of concept” trial, since double planting would be impractical on a large scale. Using average fixed and variable costs for owned equipment, and counting the expense of the second planter pass, the two practices come out virtually equal, given that there was no significant yield difference (Table 1). Calculating expenses as a single pass of a 19-inchrow planter, the row beans would come out better by about $6.39. Ted used custom planting rates for both treatments and came up with little difference in total costs between the systems.
Dave and Lisa Lubben, Monticello, tried a seedbed firmer planter attachment for the second year in 1996 (Table 1). Again there was no significant difference in yield, but yields with the firmer averaged somewhat lower.