Phase 2: Regional Optimization of Roadside Turfgrass Seed Mixtures: Regional Field Trials and Economic AnalysisStatus: CompleteReport Date: 02/13/2023 Summary: Roadside turfgrass is necessary for stabilizing the roadway, preventing erosion and filtering stormwater runoff. Maintaining it can be challenging in Minnesota’s harsh climate. Deicing salt, snowplow damage, summer heat and drought can prevent vegetation from thriving. Local agencies need cost-effective, successful seed mixes to ensure optimal roadside grass coverage. Fourteen roadside sites around the state were planted with 120 plots each to test seed mixes and growing environments. After analyzing the soil, weeds and grass coverage over two growing seasons, researchers found that mixes with multiple grass species were most successful in providing consistent coverage. Region-specific turfgrass seed mixes were recommended based on climate and soil quality. Additionally, a cost estimation tool was developed to help local agencies be confident in their roadside vegetation choices. The Local Road Research Board will continue to explore the best climate-resilient grass species and refine cost tools with more data and greater usability. Final Deliverables: Roadside Turfgrass Cost Prediction Tool (Spreadsheet #2022-16S) Regional Optimization of Roadside Turfgrass Seed Mixtures Phase 2: Regional Field Trials and Economic Analysis (Report #2022-16) Exploring Region-Specific Roadside Turfgrass Varieties (Research Summary) Related Materials: Related Research: Regional Optimization of Roadside Turfgrass Seed Mixturesÿ Regional Roadside Turfgrass Performance Testing Program Regional Optimization of Roadside Turfgrass Seed Mixtures Phase 3