Valuing Long-Term Field Experiments: Quantifying the Scientific Contribution of a Long-Term Tillage Experiment

The most well-known long-term field experiments in the world are those at the Rothamsted Experiment Station in the UK. The Broadbalk Experiment, initiated in 1843, is now more than 165 yr old. Several long-term experiments also continue in the United States. Two of the most famous are the Morrow Plots in Illinois and Sanborn Field in Missouri. Some scientists and administrators have repeatedly questioned the reasons for continuing these experiments. The basic questions remain the same, whether the year is 1895 when Lawes and Gilbert responded to a challenge about the value of their long-term experiments, or whether it is 2012 and modern-day administrators are seeking ways to decrease costs. The questions are: "Are these experiments worth the cost?" and "Are we still learning something from them?" These questions are raised more frequently as research budgets become more tenuous. So, why write another paper regarding the value of long-term field research? Do costly long-term field experiments have any value relative to what some would label "cutting edge" research? Our objective is to use the history and scientific contributions of a more recently established (1970) long-term soil management experiment at the University of Nebraska High Plains Agricultural Laboratory to provide modern evidence that maintaining existing long-term field experiments, and initiating new ones, remains a valuable and critical investment. We show how an experiment conceived to study one objective has impacted numerous other pertinent issues during the last 40 yr. We argue that scientists and administrators should be protecting existing long-term field experiments and establishing new ones to address current research issues.