Skip to main content

Urban Tree Canopy (UTC) Analysis

Urban tree canopy is the entire area covered by trees’ crowns within a geographic area, often expressed as a proportion of an area’s total land. The aim of a UTC assessment is to help decision makers understand their urban forest resources, particularly the amount of tree canopy that currently exists and the amount that could exist. A UTC assessment can be used to:

  • set canopy goals;
  • identify locations for tree planting efforts;
  • establish urban forestry strategic plans;
  • understand patterns of environmental justice;
  • inform sustainability plans; and
  • justify budget increases for urban forestry programs.

Working with UW-Madison, a tree canopy assessment was completed for all municipal* and urban areas** in Wisconsin using aerial imagery [exit DNR]. Land was classified into tree/shrub, grass/herbaceous (non-woody vegetation), impervious surface (like roads or roofs), wetland and water categories. Note that urban areas represent densely developed lands and are present throughout the state [PDF].

An aerial image of the city of Ashland, featuring dark green areas where trees are present.
An urban tree canopy assessment from Ashland. Dark green areas show where trees are present.

DNR resources

Non-DNR canopy tools

There are numerous useful resources from other organizations which help to convert land cover data into tree planting plans, to calculate benefits derived from tree canopy, or to incorporate tree canopy into planning efforts.

  • i-Tree Landscape [exit DNR] – the USDA Forest Service’s tool is the preeminent resource for assessing the ecosystem values of trees based on canopy cover. It also can help prioritize locations for tree planting based on different environmental and demographic criteria. Learn how to use the program by following these instructions [PDF].
  • EPA’s Enviroatlas [exit DNR] – offers hundreds of different layers exploring the relationship of green infrastructure, especially tree canopy, to human and ecosystem health. Fine-scale analysis is available for multiple cities in the U.S., including Milwaukee and Green Bay.
  • American Forests’ Tree Equity Score [PDF] – a tool identifying the (un)equitable distribution of trees across neighborhoods and cities, available for urbanized areas of over 50,000 people.

 

*Municipal boundaries are the borders of cities or villages. Townships are not included unless they fall within an urban** boundary. For example, some of the Town of Grand Chute falls within the Green Bay urban area. Additionally, municipalities incorporated after 2014 are not included.

**Urban areas are those lands classified by the U.S. Census Bureau [exit DNR] as densely developed territories, based on population densities. Urban areas are not limited to southeast Wisconsin, Madison and Green Bay, but are present throughout the state. Per the Census Bureau: “Urban areas represent densely developed territory, and encompass residential, commercial and other nonresidential urban land uses. To qualify as an urban area, the territory identified according to criteria must encompass at least 2,500 people.”