Metro Nashville's urban tree canopy lost 674 acres between 2016 and 2021, according to the latest five-year assessment. This decline highlights challenges in maintaining green cover amid urban growth, even as overall canopy in Davidson County rose 1.6% over 11 years. The report maps existing trees and possible planting areas to guide arborists, residents, nonprofits, and officials in bolstering benefits like reduced stormwater runoff, cleaner air, wildlife habitat, cooler summers, and higher property values.
Mapping Decline and Planting Opportunities
The assessment used 2021 aerial imagery to track changes from 2010, 2016, and 2021 across geographic boundaries. While Davidson County's canopy grew modestly, specific areas suffered. The T4 Urban transect saw the sharpest drop—a net loss of 869 acres, or 3.3%, due to concentrated development (Page 12). Nine of 14 community planning areas fall short of canopy goals (Page 25). In the Urban Services District, impervious surfaces cover 32% of land (40,814 acres), leaving over 32,000 acres of possible planting area to counter this expansion (Page 11).
Stormwater and Watershed Pressures
Impervious surfaces exacerbate flooding and pollution, but trees counter these effects. Street trees intercept rainfall, promote infiltration, curb erosion, and improve water quality as roots absorb soil moisture and release it to the air. The Kerrigan and Driftwood combined sewer systems face the highest impervious percentages among watersheds; their 790 acres of possible planting area offer a direct path to cut overflows (Page 19). Such plantings fortify stormwater management, yielding $9.85 million in annual benefits for every $1 invested.
Health, Resilience, and Policy Path Forward
Beyond water control, street trees enhance mental and physical health while cooling neighborhoods against climate change heat. This assessment equips decision-makers with data to reverse losses, prioritize planting in vulnerable zones, and meet canopy targets. Regular five-year reviews ensure accountability, turning environmental data into action that builds resilient communities.
