Richard Sutton, professor of agronomy and horticulture at the University of Nebraska–Lincoln with a joint appointment in the landscape architecture program, received an American Society of Landscape Architects Research Honor Award for his “Seeding Green Roofs for Greater Biodiversity and Lower Costs” project. The award was presented at the ASLA Annual Meeting and EXPO in Los Angeles Oct. 23 by Charlene LaBleu, Fellow of the American Society of Landscape Architects and president of The Council of Educators in Landscape Architecture, Vaughn B. Rinner, FASLA and immediate past president of ASLA, and Elizabeth Miller, FASLA, member of the National Capital Planning Commission and chair of the ASLA student jury for 2017.
Sutton’s project examined a suite of materials and techniques to improve and enhance the establishment and use of native grasses on green roofs. His areas of research focus on native plants, landscape ecology, and design or sustainable green infrastructure.
A green roof is comprised of vegetation and a growing substrate over a roof’s waterproofing membrane. It has a wide suite of benefits like reduced runoff and decreased temperatures in cities. Green roofs require added costs and often fail to survive value engineering and never get built, so the benefits remain unrealized.
According to Sutton, mono-generic, creeping species of Sedum are predominately used for green roofs and are most often hand-plugged into the substrate or placed via expensive pre-grown trays or mats. This process is costly. In a few cases, Sedum is sown as live sprigs but requires intensive establishment. Plugged Sedum, depending on its initial size and spacing, may take two years or more to meet the industry coverage standard.
Sutton's research developed an easily adopted, innovative procedure for planting fluffy-seeded native grasses instead of Sedum. He showed the potential to meet industry coverage standards and reduce green roof planting costs by about five dollars per square foot. This process also speeds up the installation and coverage times compared to Sedum plugging and increases biodiversity options. His work was supported by a Flemming research grant and employed several Nebraska UCARE students.
ASLA is the professional association for landscape architects in the United States. The society’s mission is to advance landscape architecture through advocacy, communication, education and fellowship. Sustainability has been part of ASLA’s mission since its founding and is an overarching value that informs all of the society’s programs and operations. ASLA has been a leader in demonstrating the benefits of green infrastructure and resilient development practices through the creation of its own green roof, co-development of the SITES® Rating System, and the creation of publicly-accessible sustainable design resources.