Date of Award


Document Type

Open Access Master's Thesis

Degree Name

Master of Science in Applied Ecology (MS)

Administrative Home Department

College of Forest Resources and Environmental Science

Advisor 1

Tara L. Bal

Advisor 2

Christopher R. Webster

Committee Member 1

Julia I. Burton


Sugar maple canopy dieback has been reported in the upper Great Lakes since the mid-2000s. This thesis builds on research conducted to determine some of the underlying causes of canopy dieback, which include invasive earthworm impacts, with a view toward adaptations in management of northern hardwood forests in our region. The first chapter reports a study of understory communities in a subsection of forest health monitoring plots located in four national forests near Lake Superior. Based on plot assessments from 2010 and 2021, responses of plant community composition and traits to earthworm impacts and sugar maple canopy dieback were explored. Results show that, even on broad geographic and temporal scales, plant community composition and traits appear to be influenced by both disturbance types. In particular, non-native plants and graminoids were associated with high earthworm impacts.

The second chapter summarizes results from a survey of Michigan forest managers on the topic of sugar maple health, with a focus on perceptions of and management for canopy dieback. Most survey respondents had encountered sugar maple canopy dieback and expressed concern about the impacts of the phenomenon on their management objectives, in addition to a variety of other sugar maple health concerns. Along with a summary of results, differences between forestry professionals according to affiliation with public or private institutions were also tested. Foresters with private affiliations were more likely to report relying on procedural standards upon encountering dieback, and they were more likely to have attempted stand re-initiation than publicly affiliated professionals. Results highlight the need for continued information exchange across sectors involved in the management of Michigan’s forests.

Creative Commons License

Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.

Available for download on Wednesday, December 04, 2024