Start Date
April 2026
Location
3rd floor - Library
Abstract
Green roofs provide environmental benefits in urban areas including stormwater retention, improved building thermal efficiency, floral resources for pollinators, and improved aesthetics. However, little research has investigated the use of native grasses and wildflowers on green roofs. This study evaluated the effects of native grasses and wildflowers and their management on green roof thermal performance, water retention, floral resources, and decomposition rates. We monitored 28 green roof plots consisting of seven different treatments, including (1) native grasses, native grasses accompanied by aboveground dead grass removal in the (2) fall or (3) spring, (4) native grasses and wildflowers, native wildflower and grass treatments accompanied by aboveground dead plant material removal in the (5) fall or (6) spring, and (7) unplanted plots. Plants used in this study were Schizachyrium scoparium (Little bluestem), Sporobolus heterolepis (Prairie dropseed), Asclepias tuberosa (Butterfly weed), and Rudbeckia hirta (Black-eyed susan). Early results indicate that green roofs planted with native grasses and wildflowers can improve building thermal performance and that plant management has no significant impact on floral resources for pollinators or decomposition rates. The observed benefits suggest that establishing native grass-based green roofs could provide ecosystem services in urban areas with minimal additional plant management required. Regarding pollinator resources, we will continue to monitor flower availability. The study will also benefit from lengthening the time frame of observation to gather more data on roof temperature and changes in microbial activity. As the plots are maturing, we plan to identify the microbial communities involved in decomposition.
Managing and monitoring native grass green roofs for environmental benefits
3rd floor - Library
Green roofs provide environmental benefits in urban areas including stormwater retention, improved building thermal efficiency, floral resources for pollinators, and improved aesthetics. However, little research has investigated the use of native grasses and wildflowers on green roofs. This study evaluated the effects of native grasses and wildflowers and their management on green roof thermal performance, water retention, floral resources, and decomposition rates. We monitored 28 green roof plots consisting of seven different treatments, including (1) native grasses, native grasses accompanied by aboveground dead grass removal in the (2) fall or (3) spring, (4) native grasses and wildflowers, native wildflower and grass treatments accompanied by aboveground dead plant material removal in the (5) fall or (6) spring, and (7) unplanted plots. Plants used in this study were Schizachyrium scoparium (Little bluestem), Sporobolus heterolepis (Prairie dropseed), Asclepias tuberosa (Butterfly weed), and Rudbeckia hirta (Black-eyed susan). Early results indicate that green roofs planted with native grasses and wildflowers can improve building thermal performance and that plant management has no significant impact on floral resources for pollinators or decomposition rates. The observed benefits suggest that establishing native grass-based green roofs could provide ecosystem services in urban areas with minimal additional plant management required. Regarding pollinator resources, we will continue to monitor flower availability. The study will also benefit from lengthening the time frame of observation to gather more data on roof temperature and changes in microbial activity. As the plots are maturing, we plan to identify the microbial communities involved in decomposition.
