Tree diversity in southern California’s urban forest: the interacting roles of social and environmental variables

In this study, multiple regression analyses were used to determine the drivers of species diversity in 37 southern California neighborhoods with an emphasis on the way residents shape plant communities. The relative importance of socio-economic vs environmental factors, resident preferences for specific tree attributes, and ecosystem service-based traits were considered for their effect on species composition and diversity. Likely owing to southern California’s mild climate and pervasive irrigation, only socio-economic factors and not environmental ones were found to have an effect on richness. There were a number of interactions between diversity and scale, land use type, and residential vs street trees. Links were found between traits preferred by residents and the actual distribution of trees featured these traits.