OBJECTIVE 1. Develop and evaluate management strategies for sustainable use of agricultural production, including integrated crop - livestock systems. • Sub-objective 1.1 Sustainably intensify dryland agricultural production systems by including cover crops. • Sub-objective 1.2 Sustainably intensify dryland agricultural systems by integrating crops and livestock. • Sub-objective 1.3 Sustainably intensify dryland agricultural systems by including biofuel-focused cropping systems. OBJECTIVE 2. Determine economic, environmental and production tradeoffs of improved soil management practices in the northern Great Plains. • Sub-objective 2.1 Quantify ecosystem services within dryland agricultural production systems. • Sub-objective 2.2 Determine tradeoffs between production, economic, and ecosystem service outcomes to sustainably intensify dryland agricultural production systems.
An expanding human population, increasing worldwide demand for meat and continued biofuel demand will require intensified agricultural production to meet food and fuel needs. The concept of sustainable intensification or increasing food production on the same area while minimizing environmental impacts and increasing the flow of ecosystem services has been advocated as a means to address this challenge. This project will fill significant information gaps related to management alternatives needed to sustainably intensify agricultural production systems on the northern Great Plains. We will: 1) evaluate three different methods to intensify current cropping systems common in the northern Great Plains including (i) inclusion of cover crops; (ii) integration of crop-livestock systems; and (iii) biofuel focused cropping systems; and 2) quantify ecosystem services of dryland agriculture production systems and potential tradeoffs among production, economic and environmental outcomes associated with these production systems. Successful conclusion of this project will provide producers, policy makers and government agencies with potential methods to sustainably intensify dryland agricultural production systems in the northern Great Plains and an evaluation of the impacts of these methods. These results will be communicated to stakeholders through peer-reviewed papers, on-farm research, decision tool development and other outreach activities.
This project initiated in FY14; however, there was still significant progress made toward achieving its objectives. Three different studies related to aspects of cover crop management were initiated in the summer of 2014 (Objective 1). Progress was also made on Objective 2 which is focused on determining economic, environmental and production tradeoffs associated with ecosystem services within dryland agriculture. Sites were identified, both on-location and on-farm, and compilation of long-term data was begun. Also within FY14, a lapse in funding occurred which delayed the installation of root barriers within a rainout shelter needed for testing hypothesis 1.1b. Because the root barriers could not be installed in the fall, a decision was made to take advantage of additional funding to purchase sensors for the rainout shelter which will provide better and more continuous soil moisture and temperature data. Sensor and root barrier installation is taking place in the summer of 2014. Therefore, soil equilibration (Milestone Seed Spring Wheat to equilibrate soils under Automated Rain-out Shelter) will be done using winter wheat seeded in September 2014 rather than spring wheat in May of 2014. A scientist responsible for some milestones in Objectives 1 and 2 resigned and milestones will be adjusted accordingly. A long, cool spring, rain in the middle of May and a cool June all helped to delay crop planting and development compared to seasons with more normal weather conditions. Within Objective 1, spring wheat was sown and cover crop mixtures were planted to begin evaluating the impact of cover crop mixtures on weed populations. The root barriers and sensors for the automated rainout shelter were installed over the summer. All treatments for Hypothesis 1.2 were seeded on time but first year establishment of the cover crops was poor. Weed control in these plots is a continual challenge. Different cover crops, both annual and perennial, were seeded in annual crop plots using different approaches. The focus of Objective 2 is to determine economic, environmental and production tradeoffs between conventional and conservation agriculture practices. This will involve using existing studies on location and also on-farm trials. The existing studies on location are being maintained and sites have been located for the on-farm portion. In addition, long-term data from the Area 4 farm, a farm leased for the location by the Area 4 soil conservation districts, is being compiled for use in economic analysis.
1. New tool to determine economics of crop residue harvest. Harvesting of crop residue biomass could be an important biofuel source. However, rigorous economic analysis is needed to determine the impact of removing crop biomass. ARS researchers in Mandan, North Dakota with ARS colleagues in Ames, Iowa, developed a query tool that allows data downloaded from the ARS REAPnet database to be used to construct economic enterprise budgets. They demonstrated that short-term impacts on grain profitability were lower when less crop residue was removed. Also they found that the breakeven price for crop residue in North Dakota ($54-73 per ton) was twice that of Iowa ($26-42 per ton). The power of the REAPnet data is that it comes from multiple sites under multiple different management scenarios. The new query tool will help economists develop more accurate enterprise budgets to provide for sustainable feedstock supplies.
2. Perennial grass conversion to annual crops. Economic forces have caused the conversion of many perennial grass stands to annual grain crop production over the past few years. However, relatively little information exists on the appropriate tillage method to use in the conversion process or on the impacts of previous land management. ARS researchers in Mandan, North Dakota used a perennial grass site previously grazed at different times during the season to evaluate the use of no-till or minimum-till management in the conversion process. During the four year crop rotation (soybean-corn-flax-spring wheat), annual crop yields were 3-25% higher for soybeans under No-Till than Minimum-Till depending on time of grazing and spring wheat yields were 11% higher under No-Till than Minimum-Till management. Since a severe drought eliminated corn production, the only time the two tillage techniques produced similar yields was under flax production. Previous land management that included cattle grazing affected the weed populations in the grain crop fields even four years after the livestock were removed which demonstrated the power of grazing as a weed management tool. There are 1.2 million acres of perennial grass hayland in the Dakotas and Montana, a portion of which could be converted into cropland. If this land is converted to cropland, producers should use no-till management and be aware of the impact of previous land management on weed populations and crop yields.
Archer, D.W., Karlen, D.L., Liebig, M.A. 2014. Crop residue harvest economics: An Iowa and North Dakota case study. BioEnergy Research. 7(2):568-575.
Zilverberg, C.J., Johnson, W.C., Archer, D.W., Kronberg, S.L., Schumacher, T., Boe, A., Novotny, C. 2014. Profitable prairie restoration: The EcoSun Prairie Farm experiment. Journal of Soil and Water Conservation. 69:22A-25A.
Cannayen, I., Archer, D.W., Gustafson, C., Schmer, M.R., Hendrickson, J.R., Kronberg, S.L., Keshwani, D., Backer, L., Hellevang, K., Faller, T. 2014. Biomass round bales infield aggregation logistic scenarios. Biomass and Bioenergy. 66:12-26.
Hendrickson, J.R., Tanaka, D.L., Liebig, M.A. 2014. Tillage and grazing impact on annual crop yields following a conversion from perennial grass to annual crops. Crop Management. 13(1):1-7. DOI: 10.2134/CM-2013-0081-RS.
Zilverberg, C.J., Johnson, W.C., Boe, A., Owens, V., Archer, D.W., Novotny, C., Volke, M., Werner, B. 2014. Growing Spartina pectinata in previously farmed prairie wetlands for economic and ecological benefits. Wetlands. DOI: 10.1007/s13157-014-0548-8.