Mapping the trees

John Sanborn

John Sanborn

John Sanborn is an arborist, so it made sense to tap his knowledge when it came to mapping UWM’s trees. Sanborn’s advisor, Associate Professor of Geography and director of the Conservation and Environmental Sciences program Glen Fredlund, asked him to take on the project as an independent study after the two shared a conversation about the damage to campus trees from the emerald ash borer.

For several hours a week last semester, Sanborn traversed campus marking the locations of trees with a pencil and paper and adding them to a digital map. With the records in GIS, Sanborn can sort the trees by species, locations, or relationships between each plant. The inventory replaces a 25-year-old inventory hand-marked on an old-fashioned, alphanumeric map. The inventory is helpful because it shows what species are on campus and where they are, as well as where campus plants could be in danger.

“Genetically, (clonal trees) are all basically the same plant. If an insect or disease really likes it, they can explode throughout. We look and see that we’ve got a lot of Little Leaf Lindens planted in this area. We probably shouldn’t plant more there,” Sanborn explained. “Or if we see that trees are always dying in one spot, maybe there’s some abiotic reason in the soil.”

Eventually, Sanborn’s inventory will be available to the general campus community, possibly even through a cell phone app.

“This tree data can be used in various ways by the campus community,” Donna Genzmer, Director of the Cartography and GIS Center, said in an email. “Academic programs will be able to use it and it will be incorporated in the UWM Campus Enterprise GIS for infrastructure management.”