GLO-based Historical Mapping in the Pacific Northwest
Photo courtesy USDI Bureau of Land Management, Oregon State Office
ORBIC and its partners have created maps of historical vegetation and stream networks for portions of the Pacific Northwest, based on interpretation of public land survey records of the federal government's General Land Office (GLO), and, where available, U.S. Coast Survey topographic maps ("T-Sheets"). The maps depict vegetation at coarse scale (forest, woodland, savanna, prairie) and finer scale (species assemblages). In some areas where historical stream networks were altered by later agricultural and urban development, we mapped stream alignments as delineated at the time of survey.
See the pages below for use and interpretation of GLO data, links to spatial data, history, and other resources. You can also navigate through these pages using the menu at left or from the header bar.