The university’s large, mature and majestic tree canopy plays an important role in defining campus character and creating its sense of place. Whether relaxing in the Diag, attending Shakespeare in the Arboretum or eating lunch at the Lurie Reflecting Pool, trees shape the campus experience for students, faculty, staff and visitors.

Trees also offer many ecological benefits: cooler and fresh air, wildlife habitat, stormwater control, sound absorption and carbon sequestration. Together, the more than 17,000 inventoried trees and the forested woodland systems on the University of Michigan’s Ann Arbor campus enhance human health and well-being.

So it’s no surprise that U-M foresters, horticulturalists and other specialists in Grounds Services maintain a robust monitoring and tree care program to help trees thrive in the face of urban stressors.

Across U-M’s campus, mature, majestic canopies of trees help shape the campus experience, like these near the Diag on Central Campus. (Courtesy of Campus Planning)
Across U-M’s campus, mature, majestic canopies of trees help shape the campus experience, like these near the Diag on Central Campus. (Courtesy of Campus Planning)

The backbone of the program is a thorough inventory of campus trees that tracks species, health and work performed on the trees. All trees within the maintained campus landscape are generally assessed every three years. If any obvious issues appear, forestry staff perform a more detailed risk assessment to identify and mitigate any hazards, such as hidden cavities that could compromise the structural integrity of the tree.

Dutch elm disease is one ongoing issue that Grounds Services mitigates. It results from a fungus clogging the vascular system of the tree, which prevents it from carrying water, sugars, and other nutrients throughout the tree. U-M’s 174 inventoried elm trees are susceptible to infection or already infected.

To stave off Dutch elm disease, Forestry Specialist Jane Immonen administers fungicide to a large elm tree near Hill Auditorium. (Rob Doletzky, Grounds Services)
To stave off Dutch elm disease, Forestry Specialist Jane Immonen administers fungicide to a large elm tree near Hill Auditorium. (Rob Doletzky, Grounds Services)

Since the 1980s, Grounds has been using a process called macroinjection to insert fungicide directly into the trunk of a tree to prevent or reduce the severity of the disease. Without treatment, it’s likely that these majestic trees would not exist on campus today.

Despite years of regular treatment and monitoring, an elm tree in the Law Quad recently died. The tree graced William W. Cook Legal Research Building (commonly known as the Law Library) since it was built in 1931, appearing in historical photos as far back as 1932.

Grounds Services had the dead tree removed in mid-June. To protect sidewalks and other infrastructure within the Law Quad, arborists climbed the tree using ropes, harnesses and spurs to strategically cut out sections of the tree, lowering them to the ground. Grounds and Campus Planning are developing a plan to replace the tree.

Other notable tree maintenance efforts include the close monitoring of the 200-year-old, 65-foot-tall bur oak that was relocated in 2014 prior to the Stephen M. Ross School of Business expansion. Grounds staff have observed some signs of decline but continue to nurture the tree to maximize its lifespan.

In addition, Grounds is collaborating with Matthaei Botanical Gardens to carry on the lineage of this magnificent bur oak by growing new trees with its acorns. Five saplings are in good health and will be ready to plant on campus in a few years.

As living creatures, trees don’t last forever. However, their ecological, health and aesthetic benefits leave lasting impacts. As stewards of more than 17,000 trees, Grounds Services protects the ambiance that draws many people to U-M’s campus.

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