The landscape ecosystems of UMBS were identified, classified, described, and mapped through an integrative, multi-factor approach. One hundred and twenty-five ecosystem types were identified, of which 103 occurred on outwash landforms, 5 on ice-contact features, and 17 on moraines. Ninety-five ecosystems were uplands, and 30 were wetlands. Ecological species groups were identified for uplands and wetlands; their applicability was demonstrated in mapping and in comparing ecosystem diversity among landscapes (Chapter 9). Sixty-seven cover types were identified, classified, and mapped, forming a first step in a temporal comparison of vegetative change. To complete this comparison, presettlement forest types will be determined and mapped, and the two maps will be analyzed with respect to the map of landscape ecosystem types to predict future trends in overstory vegetation. The landscape ecosystem maps, classifications, and descriptions were vital to the study of ground-cover diversity and ecosystem diversity. Taking a landscape ecosystem approach facilitated my understanding of the diversity of ground flora and of ecosystems. I was able to consider each type of diversity as an ecosystem-specific property, and the classification of ecosystems provided an ecologically sound way to consider diversity at different scales. From the general landforms and ecosystem groups to the specific types, biological diversity was a product of climate, physiography, soil, vegetation, and human-caused disturbance. Similarly, ecosystem diversity was related to patterns of physiography and soil. By relating the two types of diversity in this dissertation, I hope to have provided impetus to the movement towards ecosystem-centered conservation of diversity.