The goal of my research program is to investigate what makes up the vegetation in cities and town and what environmental or ecosystem services this vegetation provides to local and regional populations. The research initiates field studies and develops computer models to assess the urban forest structure, functions, and values for urban areas across the globe. One of the research goals is to integrate urban forest ecosystem services (e.g., air quality improvement) within various environmental regulations (e.g., Clean Air Act). Tools are also being developed to aid in management and planning decisions to sustain urban forest health and services. Long-term monitoring programs are investigating how and why urban forest change through time so better management plans can be developed to sustain this important resource. Specific research projects include: