The Rodale Institute Farming Systems Trial®
The Rodale Institute's oldest experiment … and a national and international treasure.

By Laura Sayre

September 30, 2003: Paul Hepperly, The Rodale Institute's Research Manager, is looking into securing some kind of historical designation for the 12-acre site. But there are no time-weathered buildings here, just crops and soil and grassy field margins. Initiated in 1981, The Rodale Institute Farming Systems Trial® (FST) is the longest-running side-by-side comparison of organic and conventional farming systems in the US, and one of the oldest in the world. What began as a 5-year controlled study of what a typical American grain farmer would go through to give up chemical fertilizers and pesticides has matured into a complex, interdisciplinary, collaborative project that will be continued indefinitely. As The Rodale Institute® President John Haberern puts it, the FST is "a living experiment. It doesn't have an end."

The FST compares three strategies, or 'systems,' for grain production: one conventional, one livestock-based organic, and one legume-based organic. The conventional system follows a 5-year rotation typical of many farms across the Midwest--corn, soybeans, corn, corn, soybeans--and receives fertilizer and pesticide applications according to the standard recommendations provided by Pennsylvania State University. The livestock-based organic system follows a 5-year rotation of corn, soybeans, corn silage, wheat, red clover and alfalfa hay, with aged cattle manure applied in the two corn years. The legume-based organic system is structured around a 3-year rotation of hairy vetch/corn, rye/soybeans, and wheat. The two organic systems receive no chemical inputs for fertility, weed or pest control.

One of the key features of the FST is its scale--small enough to follow rigorous scientific procedures for experimental design but large enough to be worked with regular equipment and to generate results readily applicable to normal farm operations. The level field of mostly shale-y, somewhat compacted silt loam is broken into eight blocks, or replications, with each block containing three plots, 60 ft wide by 300 ft long, and each plot divided lengthwise into three subplots. Eight replications of each of the three cropping systems are randomized across the blocks; while the subplots allow each rotation to be started simultaneously at three points, so the effects of annual weather variations are distributed across different phases of the cropping cycle. Datasets from the FST include weather records; energy and labor inputs; corn, soybean, wheat, and forage yields; weed, crop, and cover crop biomass figures; nutrient analyses of crops and cover crops; soil carbon and nitrogen levels; soil percolation rates; nitrate, phosphate, and pesticide leachate data; soil biodiversity surveys; and economic return evaluations.

Results from the FST have been reported in dozens of scientific papers over the years, and include this core finding: corn and soybean yields are the same across the three systems. Although corn yields were about a third lower in the organic systems during the first four years of the study, in subsequent years the organic systems actually outperformed the conventional system under droughty conditions. The reason will come as no surprise to anyone who has managed soils organically: while the portions of the field under conventional management have suffered further degradation from wind and water erosion (when The Rodale Institute purchased the property in the late 1970s it had been used to grow conventional corn for almost two decades), the portions under organic management have shown steady improvements in organic matter, water infiltration, microbial activity, and other soil quality indicators.

Comparisons between the two organic systems have also been of great interest, suggesting to The Rodale Institute's Farm Manager Jeff Moyer, for instance, ways to improve his management of the rest of the Rodale Farm. Excess nitrogen in the legume-based organic system has led Moyer to reduce seeding rates for hairy vetch, resulting in less nitrate leaching … not to mention reduced seed costs. The overall benefits of cover-cropping in both systems have moved him more and more towards reduced tillage. "In the end it's a combination of methods that seems to work best," Moyer explains. "You have to think in terms of ever longer and more complex rotations."

But the lessons of the FST have spread far beyond Rodale, as the field has played host to a wide range of related research projects by university, government, and independent investigators.

• Dr. David Douds of the Agricultural Research Service has examined mycorrhizal fungi populations under the three different farming regimes.
• Dr. David Pimentel of Cornell University has compared total energetic requirements of all inputs for each system.
• The Pennsylvania Department of Environmental Protection has in part financed the monitoring of water passing through each system for nutrient leaching and chemical contamination.
• Dr. James Hanson of the University of Maryland has conducted an economic comparison of the conventional versus the legume-based organic systems.
• Warren Porter of the University of Wisconsin plans to investigate variations in nutritional content of the feed and forage coming off the FST plots.
• Dr. Michelle Wander of the University of Illinois has studied soil organic matter characteristics in the FST and is now developing new soil testing procedures to evaluate cropping system efficiency.
• Dr. Silke Ullrich of the USDA's Sustainable Agriculture Systems Lab in Beltsville, Maryland, is using the FST fields to research weed population dynamics under conventional and organic management.
• Dr. Jorgen Olesen, from the Danish Institute of Agricultural Sciences, is using FST data to improve nitrogen modeling in farming systems and will go on to compare crop rotation performance in continental and maritime climates.

Because of the many emergent properties of complex agroecosystems, Paul Hepperly feels that the collaborations generated by the FST are just as important as the raw results. "The value of a study like this lies in its holistic aspects--what researchers from different disciplines have learned from each other, and what we've learned from them. We're only just beginning to understand what's at work."