Columbia’s city government will be using high-resolution aerial photography to map vegetation and aid in enforcement of tree preservation laws.
A 180-square-mile area will be photographed during a fly-over in June while trees are fully in leaf, and the images will serve as a baseline for future analysis of changes in vegetation and to monitor land disturbance.
City Manager Bill Watkins said the Columbia City Council views tree preservation as a high priority. A photographic inventory of vegetation could lead to city purchases of land with old-growth trees, also known as climax forest, protected by the tree preservation ordinance.
Once the analysis has been completed, Watkins said, city administrators will be in position to identify areas for preservation.
“The only way to preserve it is for the city to own it,” Watkins said. “Before we can do that, we need to define and determine which areas are really important and what we need to preserve.”
Newly elected Third Ward Councilman Karl Skala, outgoing vice chairman of the Environment and Energy Commission, said that locating and tracking changes in hardwood trees is one of the primary purposes of the aerial images. Climax species, including oak, hickory, hard maple, ash, walnut and others, are protected under the city tree preservation law, and Skala said the inventory could help with enforcement by providing information about private tracts without an on-site inspection by the city arborist.
The city plans to track changes over time by leveraging state-funded, lower-resolution mapping every two years after the initial baseline assessment.
“That assessment would be one way to make sure that everyone knows what” is being cleared from a piece of land “to make sure people aren’t violating the letter of the law,” Skala said.
The vegetation survey is the final component of an ongoing natural resource inventory that can help review policy decisions related to development and conservation. The city’s existing resource database is extensive, including mineral resource concentrations and water quality, but it lacks a detailed vegetation map.
On March 5, City Council decided to draw on a grant from the Federal Highway Administration for the majority of the $80,000 needed for the project, with $12,500 from both the water and electrical utilities and the remaining $5,000 coming from the general fund.
The city has had access to black and white aerial imagery paid for by the state for a number of years, but it has been without the color data or higher resolving power that will be generated by the new photographs to help track vegetation more efficiently.
“The city has a lot of information already,” said Tim Haithcoat, director of the MU Geographic Resource Center. “What they don’t have is high resolution. You can do it with the lower-resolution imagery, but the tools have advanced since (the city) got that imagery.”
In 2001, the city partnered with the MU Center for Agricultural, Resource and Environmental Systems to obtain higher-resolution color photographs that would better allow analysts to identify plant species. The resolution of the images produced by CARES only allowed for a general assessment of vegetation, which the city now hopes to replace with more well-defined photographs.
Haithcoat will be one of a three-person team that will be analyzing the new imagery after it is completed early this season. Despite the extensive use of computers to analyze the data, the assessment will take about six months from the time the team receives the new photographs, he said.
The images will resolve 140 times more detail than the previous photos provided through CARES. It will allow more accurate species identification as well as other applications of interest to the city, such as planning water runoff and drainage requirements by calculating the amount of paved surfaces in the city.
Once Columbia has the new imagery, it should be made available for public viewing along with the analysis and reports, Watkins said.