Building Cost-Effective Prairie for Multiple Nutrient Reduction Practices
The contour prairie strip reduces surface nutrient runoff for about the same cost as cover crops, and does not carry the uncertainty of replanting every year. Prairie strips reduce concentrations of shallow groundwater nitrates, and prairie root systems fuel the denitrification process. Building prairie in the agricultural landscape also enhances other ecosystem services including soil quality, wildlife habitat and resilience to flooding. Yet conservation agency staff, professional farm managers and other technical service providers may be reluctant to recommend prairie contour strips because of concerns about a successful outcome.
Cost effective methods of prairie establishment are not well known outside the ecological restoration community. The goal of this project is to improve the effectiveness and predictability of prairie contour strips and other prairie applications, thus reducing barriers to implementation. This will be done through applied research, establishment of training/demonstration sites, and training for practitioners.
Both research and demonstration prairie plantings will consider appropriate species and planting methods for saturated buffers, and for marginal lands with either extremely wet or extremely dry soils. Vegetation sampling will be done with the cost per thousand plants established, and species diversity and plant size reported. To address the goal of reducing barriers to the use of prairie for nutrient reduction, a technical report on earlier experiments and demonstrations, plus research summaries on seed mix design, mowing, season of planting, and stand development/troubleshooting will be created. At least four presentations will be made to agricultural audiences; web resources and printed materials for agricultural audiences will be developed; and there will be continued collaboration with the ISU STRIPS project.
Note: Project reports published on the INRC website are often revised from researchers' original reports to increase consistency.
The complete final technical report is provided here: Cost-effective seed mix design and first-year management (PDF). Key highlights, include:
- Diverse, moderately priced seed mixes with a balanced seeding rate of grasses to forbs produce nutrient reducing prairies with the most additional conservation benefits at reasonable cost.
- These benefits accrue faster when paired with first-year mowing management.
- Nutrient reducing prairies with multiple other conservation benefits can be successfully applied to dry marginal soils when seed mixes are designed (without increasing cost) to include dry adapted native plants.