Native vegetation on a high altitude green roof: A biodiversity study

Background/Question/Methods

Green roofs have been noted for their ability to lower energy costs, mitigate storm water runoff and reduce the urban heat island effect. However, the very nature of a green roof suggests an environment subject to intense sun exposure, limited moisture availability and desiccating winds; an environment not conducive for high levels of biodiversity. In June of 2011, 4,400 native plants, comprised of 62 species were planted in a 3,400²ft semi-intensive green roof at the University of Wyoming in Laramie Wyoming.  Seasonal monitoring of survivorship, percent cover and succession has been used to evaluate the success of native plant species for use in green roof technology. Arthropod sampling has been conducted to reinforce the use of native plants to support arthropod communities with an emphasis on native and nonnative pollinators.

Results/Conclusions

Preliminary data suggests that native plants are successful in green roof technology with over 90% of species surviving.   Arthropod sampling indicates that the native plant community supports and encourages arthropod diversity.  Successful application of native plants will serve as a model system for the promotion and use of regionally appropriate native plant species in green roof technology and encourage native biodiversity.