Here's a really interesting study be the USDA on the valuation of urban forests in TN. In this case it's $80 billion dollars when taking carbon storage, energy savings, air pollution removal, and
structural value into consideration.
The USDA set out to study the environmental and economic benefits and uses of trees in towns, cities, and communities in TN. Using the forest services i-Tree Eco software (itreetools.org) researchers took information from 2418 trees and saplings across 255
field plots. Variables noted include species, diameter at breast height, height, crown dimensions,
foliage transparency, damage, and proximity to buildings. The information was used to value the forests, but also will be used to help keep them healthy and flourishing.
Read the full study at: USDA - Urban Forests of Tennessee