Using Crop Diversity in No-till and Organic Systems to Reduce Inputs and Increase Profits and Sustainability in the Northern Plains
A major deterrents to adopting no-till or organic crop production in the Northern Great Plains is concern about weed management problems during the transition from conventional systems and moisture conservation associated with crops as alternatives to fallow. A large-scale experiment was established at Moore, MT to compare no-till and organic systems to conventional small grain production systems (Table 1). A similar systems experiment was established at Bozeman, MT (Table 2). The goal was to evaluate farm profitability and sustainability within a system that increases crop diversity and reduces off-farm inputs. Thus we have been quantifying production, profitability, and weed population dynamics among the production systems in the experiment at Moore and on Farms in north central Montana.
Understand weed dynamics to predict species shifts within organic and no-till production systems.
Determine crop performance and water use efficiency within organic and no-till systems.
Quantify input levels and costs for organic and no-till systems, including both purchased and operator supplied inputs.
Quantify profitability (net return) or organic and no-till systems.
Educate producers on potential benefits of organic and no-till systems through dissemination of research results.
The fertility conditions are expected to change under the organic management approach as green-manure use is more fully implemented. Seed bed preparation will also improve as we move to improved equipment. The annual monocot weeds appear to be much more spatially dispersed and less vigorous in the organic system as compared to the more conventional reduced tillage systems. The annual dicot weeds are on a trajectory to local extinction in the organic system. Our hypothesis is that the weed responses in the organic system can be mostly attributed to the increased level of tillage and later crop planting dates.
Impacts and Contributions/Outcomes
The predominant small grain cropping system of the Northern Great Plains has utilized a crop fallow rotation under an assumption of moisture conservation. More sustainable systems may include the use of more diversified and organic systems that reduce inputs. The transition to more sustainable systems represents a challenging step for producers and requires prediction of how crops and weeds will perform. Weed population dynamics in response to more sustainable agricultural systems on the Northern Great Plains is critical to implementation of these systems. This study has already begun to show significant differences in weed behavior under different crop management and promises to allow prediction of weed responses to a wide range of management approaches from organic to high- input conventional. To our knowledge, there are no other studies that have simultaneously measured spatial and temporal dynamics of weed populations. Thus, there has been limited ability to predict the economic thresholds or distributions that determine optimum weed management under most conditions.