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Tree Canopy Protection Asheville’s New Ordinance A Step Toward Smart Growth
The urban tree canopy in French Broad River Park in Asheville illustrates multiple benefits of trees including recreation, stormwater mitigation, and shade. AMY SMITH PHOTO
BY AMY SMITH The benefits of urban forests are immense. Not only are trees valued for aesthetic beauty and shade, but tree cover in cities also provides benefits to human health and social well-being. Urban forests and greenery are associated with improved mental health and physical wellness. Trees work as a part of the green infrastructure of a city to remove air pollution, mitigate stormwater, reduce flooding, sequester carbon dioxide, provide habitat for wildlife, and improve comfort and cooling for residents by mitigating the urban heat-island effect. Properly placed trees can reduce energy use for homes and businesses, as well as increase property values. These social, economic, and environmental benefits of the urban forest all contribute to the triple bottom line of long-term sustainability in the City of Asheville.
The data Like many growing cities, Asheville has struggled to balance the demand for new development with the need for a healthy, mature, and thriving tree canopy. Dedicated citizen groups, nonprofit partners, and city government have all worked together to address the problem of tree canopy loss. The City of Asheville Urban Forestry Commission (UFC) initiated several key projects in the
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Asheville tree canopy change per census tract from 2008 to 2018. MAP COURTESY OF THE ASHEVILLE URBAN TREE CANOPY STUDY BY DAVEY RESOURCE GROUP
last few years to collect data and implement new policies for tree canopy protection. In 2019, the city contracted with Davey Resource Group to study changes in Asheville’s tree canopy over the past decade. Data from 2008 was compared to 2018 conditions and found Asheville lost 6.4 percent of the total tree canopy in that time frame. The amount of tree canopy can also be used to calculate ecosystem services including carbon sequestration and stormwater capture.
In 2008, it is estimated that Asheville’s urban tree canopy coverage provided $82 million worth of carbon sequestration. Canopy loss in the next 10 years resulted in a loss of $7 million worth of carbon capture benefits. Additionally, from 2008 to 2018, the loss of canopy resulted in an increase in stormwater runoff that cost the city an estimated $1.6 million. Long-term planning to retain and increase canopy cover in the city is a goal that will save money in addition to preserving the legacy of natural beauty in Asheville. In 2019, the city of Asheville worked with a team from NASA Develop to conduct a study on the urban heat-island effect, which explores the measurable increase in temperatures in a city compared to surrounding areas due to vegetation loss combined with heat capture from the built environment. The study found that census tracts with high vulnerability (high poverty and/or high rate of elderly residents) were often also those with low tree canopy and the highest temperatures. This inequity in tree canopy distribution and the resulting impacts on human health and cooling costs aligns with recent research on historic redlining practices in Asheville and the impacts on tree canopy. Restoring the tree canopy in historically under-served neighborhoods will help ensure that trees are distributed more equitably in Asheville.
Addressing this inequality of tree cover can improve living conditions for all city residents.
The ordinance From this data, the UFC worked together with city staff to create a new Tree Canopy Protection Ordinance that updated the existing tree-save policies in the Unified Development Ordinance (UDO). The new ordinance uses the data from the canopy study along with a zoning overlay to structure the amount of canopy that must be preserved on a development site. Asheville City Council voted unanimously to approve the ordinance in September 2020. Leaders cited the ordinance’s alignment with the Living Asheville Comprehensive Plan, particularly in creating a healthy and expanding urban tree canopy; protecting land and water assets; making streets more walkable, comfortable, and con-
A red oak tree thrives at Rainbow Community School Playground. SOPHIE MULLINAX PHOTO
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