From the text... 'The purpose of this report is to attempt to evaluate the evidence for widespread human manipulation of the environment in the Midwestern United States. The study will focus primarily on the states of Illinois, Indiana, Iowa, Michigan, Minnesota, Missouri, and Ohio. Two main issues will be investigated. First, how did the land-use practices of Native Americans and European/American settlers influence the vegetation around them? And second, what role, if any, did human land-use practices play in the development and/or maintenance, of oak ecosystems? METHODS: Information on land-use practices from prehistoric times until the early twentieth century was needed to examine the impact of Native Americans and European/American settlers on the landscape. Historical materials such as the travel narratives of explorers or the journals of settlers were examined for first-hand information on the past few hundred years. Additional historical information was obtained from county and state histories, gazetteers, reports from the U.S. Department of Agriculture, and anthropological publications. Archaeological studies provided insight into prehistoric times, while information on vegetation and climate change was obtained from pollen and charcoal studies.'