Inequities in urban tree care based on socioeconomic status

Abstract

Urban trees are key elements for livable cities because they provide ecological, social, and economic benefits. Due to their importance, tree care should assure their welfare and ecosystem service provision. Among tree care strategies, pruning is highly controversial because it can be performed poorly, risking tree and human welfare. For the first time, we investigate whether the “luxury effect”, that describes a positive effect of human wealth on plant diversity, extends to urban tree care. In the Latin American city of Santiago de Chile, we sampled trees in 120 sites located in residential areas of different socioeconomic status. At each site, a trained forester evaluated each tree recording the occurrence and quality of pruning. We used a Generalized Linear Mixed Model with logistic distribution to estimate the probability of good pruning according to socioeconomic status. We found most trees (82% of 510 trees) were pruned and most of them had poor corrective pruning applied. Good pruning increased with socioeconomic status of neighborhoods: 15%, 31%, and 54% of pruned trees in low, medium, and high socioeconomic status, respectively. There was a significantly higher probability of finding well pruned trees in residential areas of high socioeconomic stratum than in lower strata. Our study reveals that trees in poorer zones are massively affected by the extended application of poor pruning that, in turn, risk ecosystem service provision for vulnerable people. Urgent strategies need to be implemented to prevent tree damage in Santiago de Chile, especially in lower socioeconomic zones. Due to the widespread application of poor pruning on residential trees in our city and the paucity of local and global research on the relationship between socioeconomics and urban tree care practices, we make a call to investigate these patterns, especially in cities that exhibit social, economic, and environmental segregation.