Urban Tree Canopy (UTC) refers to the layer of tree leaves, branches, and stems that provide tree coverage of the ground when viewed from above (US Forest Service). Analyses such as these, for cities large and small, provide a birds-eye view of land use change and can be used to help understand the environmental impacts of land-use decisions.
Depletion of Georgia’s Tree Canopy
According to a 2006 study, the Atlanta region lost an average of 50 acres of tree canopy per day between 1991 and 2005. For each acre of tree canopy lost, one acre of impervious surface was gained.
The study, by Dr. Liz Kramer with the Natural Resources Spatial Analysis Laboratory (NARSAL), compared satellite imagery from 1991 and 2005 to document the rate of tree loss in Georgia. The data was updated in 2008 to include all counties across the state.
Importance of Maintaining Tree Inventories
An inventory can help improve your work scheduling and cyclical maintenance program, improve your ability to respond to storm damage, enhance efficiency when responding to constituents’ requests, and locate all trees of a single species in case of a disease outbreak.
To effectively set Urban Tree Canopy goals, a tree inventory is a valuable tool and is essential in developing a management plan.
- Tree inventories document the species, diameter, health and location of community trees. Software tools such as iTREE are commonly used.
- To be most effective, an inventory should be continually updated and linked to Geographic Information Systems (GIS).
- Inventories range in costs from a few thousand dollars to tens of thousands of dollars.
Helpful Resources
| Title | Description | Document Type |
|---|---|---|
| Center for Watershed Protection | Learn how to conduct Urban Tree Canopy assessments and goal setting. | External Website |
| City of Atlanta Interactive Maps | Assessing Urban Tree Canopy in the City of Atlanta. | External Website |
| Declining Urban and Community Tree Cover Report | National results indicate that tree cover in urban/community areas of the United States is on the decline at a rate of about 175,000 acres per year, which corresponds to approximately 36 million trees per year. View report. | External Website |
| Five Year Plan for Georgia’s Urban & Community Forest | The five-year plan is a guidance document for the Urban & Community Forestry program of the GFC and the GTC. The plan is developed by a diverse group of industry leaders in Georgia. | |
| Forest Service’s Forest Inventory and Analysis | The Forest Service’s Forest Inventory and Analysis (FIA) program has provided the Nation’s forest census since 1930. A system of forest measurement field plots across the United States serves as the program’s foundation. | External Website |
| iTree Software | i-Tree is a state-of-the-art, peer-reviewed software suite from the USDA Forest Service that provides urban and rural forestry analysis and benefits assessment tools. | External Website |