City Trees

preventable annual premature deaths were calculated city-wide and for areas of lower versus higher socioeco- nomic status (SES). It was estimated that 403 premature deaths overall, including 244 premature deaths in lower SES areas, could be prevented annually in Philadelphia if the city is able to meet its goal of increasing tree canopy up to its goal of 30%. Bringing all of Philadelphia, and especially its poorer neighborhoods up to the 30% goal is not without challenge. Nevertheless, poli- cymakers were encouraged in valuing urban greening efforts as health-promoting and life-saving measures. Green space improvement, crime, fear and safety Vacant and blighted urban land is a widespread and potentially risky environmental condition encountered by millions of people on a daily basis. About 15% of the land in US cities is deemed vacant or abandoned, translating into an area roughly the size of Switzerland – over 9 million acres of otherwise beneficial spaces that remain neglected. To study whether the greening of vacant urban land reduces the frequency of violence and crime as well as perceptions of fear and safety in communities, a randomized controlled trial was con- ducted in Philadelphia using standardized landscape treatments (Branas et al. 2018). A total of 541 randomly sampled vacant lots were allocated into treatment and control sites, and 445 randomly sampled participants were surveyed over a 38-month study period. It was discovered that participants living near treated vacant lots reported significantly reduced perceptions of crime, vandalism, and safety concerns when going outside their homes, as well as significantly increased use of outside spaces for relaxing and socializing (Branas et al. 2018). They also reported significantly reduced symptoms of depression and feelings of worthlessness (South et al. 2018). In addition, there was significant reduction in crime overall (-13.3%), gun violence (-29.1%), burglary (-21.9%), and nuisances (-30.3%) after the treatment of vacant lots in neighborhoods below the poverty line. This study helped to determine that blighted and vacant urban land affects people's perceptions of safety as well as their actual, physical safety. Restoration of vacant urban land can be an effective and scalable infrastruc- tural intervention to significantly reduce persistent urban problems such as gun violence, crime and fear. Tree planting and gentrification Several studies have shown that trees can increase the sales and rental price of homes (Donovan and Butry 2010; Donovan and Butry 2011). This is not surprising, given the wide range of benefits that trees provide. However, if trees increase home values, then they may also displace long-term residents who can no longer afford to live in a neighborhood as the sales and rental prices of homes go up. This process is known as gen- trification. Several studies have shown that major changes to a neighborhood's natural amenities, such as adding a park, can cause gentrification (Anguelovski et al. 2017; Curran et al. 2012). It's not clear whether smaller changes to a neighborhood's natural amenities, such as tree planting, can also gentrify. To answer this question, scientists analyzed 30 years of tree-planting data in Portland, Oregon. They found evidence that The Tioga Hope Garden in the Nicetown-Tioga neighborhood of Philadelphia program, which, with community input and collaboration, has transformed more lots in Philadelphia into green spaces. Photo Courtesy of Pennsylvania Horticultural 18 CityTREES

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