PRAIRIE-BASED GREEN ROOFS: LITERATURE, TEMPLATES, AND ANALOGS

Native prairie species have been both promoted and questioned in their ability to serve as vegetative covers for green roofs. The green roof environment with its exposure to intense sun and wind and limited moisture restricts the capacity for a large diversity of species. The result has been, in many cases, a standard, low-diversity mix of Sedum species often focused on ornament and minimizes the potential for wider environmental benefits. We reviewed the ecological literature on prairie and grassland communities with specific reference to habitat templates from stressed environmental conditions and examined analogs of prairie-based vegetation on twenty-one existing green roofs. We found that many, but not all prairie and grassland species will survive and thrive on green roofs, especially when irrigated as needed or given adequate growing medium depth. We raise several important questions about media, irrigation, temperature, biodiversity and their interactions needing more study.