Auburn Cotton and Corn Sustainability Project

The study was part of the Future of Farming project, funded by the Natural Resources Conservation Service (NRCS), spanning five years (from 2020 to 2025). The project encompassed three components: farmer-owned demonstration sites in different regions of Alabama, "Farmer-Focused Learning Groups" composed of local farmers, crop consultants, Extension agents, and NRCS representatives, and an incentive payment program to implement cover crops. Therefore, with the assistance of a local extension agent, five farmers were selected from the Central Alabama focus group. The farmers’ selection criteria included crop rotation type (cotton, peanut, or corn), use of irrigation, use or not use of conservation practices. Crop management data from four farmers from the period 2019 to 2022 was input into the calculator.  The study started with the goal of using the sustainability indicators as benchmarking tools to facilitate dialogues and knowledge exchange among farmers concerning their experiences and challenges related to conservation practices. Data analyses and comparisons were done by "pairing" farmers with the same crop and year, but different management practices. This strategic pairing resulted in divergent outcomes, intended to foster discussions and engagement.

Comparisons among each pair of farmers were done with respect to the impact of their management practices on indicators such as energy use, water quality, soil carbon, soil conservation, and greenhouse gas emissions. Three case studies were created: Case Study 1 examined energy use and water quality between corn fields from Farmers 14 and 22 on 2021 growing season. Case Study 2 focused on soil carbon and soil conservation between cotton field of Farmer71 in 2019 simulating the field on conventional tillage versus strip tillage. And Case Study 3 analyzed greenhouse gas emissions between cotton fields from Farmers 71 and 17. These case studies were selected to represent different practices used not only by the five farmers selected for this study, but the practices used by farmers in Central Alabama.

Results

The results were during two field days (June and July 2023) using large posters to illustrate comparisons of the impact of agronomic practices on the sustainability indicators and metrics.

In Case Study 1- a comparative analysis of two corn farmers, F22 practicing strip tillage on the study field and F14 using conventional tillage, revealed differences with respect to energy use. Besides the difference in tillage method, they present difference in fertilizer rate too. These two fields differed among the amount of fertilizer applied and this was reflected on the total BTU, protectant energy, and management energy. These differences were used to discuss the impact of crop management on energy, and green house gasses. The differences in management practices, especially nutrient management were evaluated for their impact on water quality. For example, farmer 14, opting for a higher fertilizer rate, fewer nitrogen splits, not using cover crops and doing conventional tillage reflected on a lower simulated water quality score compared to farmer 22.

Soil Carbon. Case Study 2 examined the cotton farming methods of farmer 71, who practices conventional tillage. The study simulated a transition from conventional tillage to strip tillage, enabling a comparison of their potential effects on soil carbon buildup or depletion. During conventional tillage, the farmer made 16 trips to the field, including disking two times, hipper, planting, harvesting, and stalking chopper operations. In contrast, with strip tillage, the farmer reduced field trips by 3, omitting the disk and ripper operations. Under conventional tillage, the simulation of soil carbon score was -0.47, indicating a high risk of soil carbon loss, and of organic matter loss. Transitioning to strip tillage raised the simulated score to 0.23, meaning a significant potential for soil carbon gain.  Therefore, this transitioning from conventional to strip tillage reversed the field's carbon dynamics, highlighting the impact of different tillage methods on soil carbon levels and conservation.

These study cases helped understanding how to use the fieldprint calculator and the different indicators and how the data can be analyzed to evaluate the impact of conservation practices. We found the tools no very easy to use for farmers or even consultants, therefore trainings are very important.