The Long-Term Agro-ecological Research (LTAR) experiment: Ecological benefits of organic crop rotations in terms of crop yields, soil quality, economic performance and potential global climate change mitigation
Work continues in Year 16 of a long-term experiment comparing organic and conventional crop rotations. Adverse weather conditions in 2013 affected the production and performance of several crops in the rotations being studied. As a consequence of extended wet weather in spring, poor stands, delayed weed management and subsequent high weed populations, organic soybean yields were 26 percent lower than 2012. Organic corn yields were, however, greater than conventional corn, even when re-planting occurred on June 8.
How can we gauge the viability of organic cropping systems in relation to the agronomic, economic and soil quality effects in conventional cropping systems?
The project measured various parameters and determined that, even with reduced yields, organic crops were more lucrative because of lower costs of production coupled with higher premium prices compared to conventional crops. Soil quality effects were evaluated every fall after harvest by quantifying a suite of biological, chemical and physical soil properties. Researchers measured soil organic C, total soil N, microbial biomass C, N mineralization, macroaggregation, extractable NO3-N, NH4-N, P, K, Mg, and Ca, electrical conductivity, and bulk density.
Cynthia Cambardella, Craig Chase
Year of Grant Completion
Delate, Kathleen; Cambardella, Cynthia A.; and Chase, Craig, "The Long-Term Agro-ecological Research (LTAR) experiment: Ecological benefits of organic crop rotations in terms of crop yields, soil quality, economic performance and potential global climate change mitigation" (2014). Leopold Center Completed Grant Reports. 461.