Environmental researchers Stephanie Carlisle and Max Piana recently presented green roof research findings at the 11th annual Cities Alive Conference in San Francisco, attended by international green roof professionals, designers, and researchers. The theme of this year's conference was resilience, with presentations and research exploring the many ways in which green roofs and walls contribute to social, environmental, and economic resiliency within our cities. The role of green roofs in urban water management and the potential for agriculturally-based green roofs were topics of particular interest.  

Growing Resilience: Long Term Plant Dynamics and Green Roof Performance

Focusing on studies of two mature green roofs, one intensive and the other extensive, Stephanie and Max discussed changes in green roof vegetation, challenging the audience to consider the long-term dynamics and transformations of these living systems. Questions under consideration included:  

• How does green roof vegetation change over time?
• How does vegetation performance relate to building and site context?
• How do the growth trajectories of an extensive and intensive green roof compare?

They also asked audience members to consider whether changes can be considered positive or negative with respect to building performance, and whether the emergence of unplanted species might increase the functional capacity of roofs and their resilience to disturbance over a significant lifespan. Stephanie and Max reported that the conference was an exciting opportunity to engage in dialogue with leading green roof researchers from around the world.