Examining the impacts of urban tree structure and condition on adult depression in the United States

Abstract

Urbanization can stimulate economic growth through industrialization; however, urbanization can also lead to dense development and high population densities. Both factors cause stress and negatively impact the quality of life of inhabitants living in cities. In response, a growing body of research has examined the association between urban trees and human health, in general and psychological well-being, in particular. Although this literature has tended to focus on tree canopy broadly, questions remain regarding the effects of specific tree characteristics (e.g., crown dieback, tree with damage, and leaf area). This study examines the association between adult depression and tree structure and condition metrics in ten cities across the United States. Adult depression data were obtained from the Centers for Disease Control and Prevention, and individual tree structure and condition data were calculated using the Urban Forest Inventory and Analysis Program. The linear mixed-effects model showed a positive relationship between depression and tree crown-dieback percentage (p = 0.03). Understanding the interplay between individual tree characteristics and adult depression can inform urban planning, design, and maintenance practices.