Milwaukee’s urban forest, 2021
| Authors: | Dan Buckler, Sjana Schanning, Christina Herrick, Robert Hoehn, Katie Jennings, Alexander R. Young |
| Year: | 2026 |
| Type: | Resource Bulletin |
| Station: | Northern Research Station |
| DOI: | https://doi.org/10.2737/NRS-RB-146 |
| Source: | Resour. Bull. NRS-146. Madison, WI: U.S. Department of Agriculture, Forest Service, Northern Research Station. |
Abstract
Data collected from over 200 plots in Milwaukee, Wisconsin from 2015 through 2021 reveal that the city has an estimated 3.7 million live trees at least 1.0 inch in diameter across all ownerships. The most common tree species by number are common buckthorn, boxelder, and green ash, while those at least 5.0 inches in diameter are led by green ash, boxelder, and Norway maple. The largest number of trees (31.4 percent; 1.1 million trees) are found on forest land. Trees on public lands total 2.1 million and account for over 57 percent of all live trees. Trees at least 15.0 inches in diameter are only 7 percent of the population, but represent 48 percent of all trees’ leaf area, which in turn produce many of the benefits of the urban forest. It is estimated that the urban forest produces over $12.6 million in annual benefits, while those trees represent a compensatory value of $1.24 billion. Buckthorn is the most common invasive species, covering 3.7 percent of the city’s area, and ash trees overwhelmingly account for the city’s dead trees (88 percent of the dead trees at least 5.0 inches in diameter). The information presented in this report can be used to support urban forest management programs and to inform policy and planning to improve environmental quality and human health in Milwaukee. The analysis also provides a basis for monitoring changes in the urban forest over time.