"After inputting raw data from the inventory in i-Tree, Tree Pittsburgh found that the city’s street trees — strictly those planted in sidewalks and medians — provided $2.4 million worth of environmental and aesthetic value every year. (A 2011 analysis of Pittsburgh’s total tree cover, which involved sampling more than 200 small plots throughout the city, showed a value of between $10 and $13 million in annual benefits based on the entire urban forest’s contributions to aesthetics, energy use and air quality.) The values take into account energy savings from shade, impact on the city’s air and water, and the boost in property values associated with leafy neighbors.
"Given the city’s annual expenditures of $850,000 on street tree planting and maintenance, Tree Pittsburgh concluded that the city received $3 in benefits for every dollar it invested in street trees. That math helped convince the city that upfront investment in trees was worthwhile, and so last summer Pittsburgh released a detailed master plan
for maintaining and expanding its urban forest over the next two decades."
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