ORNHIC has created maps of historical vegetation and stream networks for several areas of the state, based primarily on interpretation of public land survey records of the federal government's General Land Office (GLO). 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.

GLO Land Surveys, Ecology, and History

GLO Historical Vegetation Maps -- Oregon

Downloadable Maps

Methods and Vegetation Classification

GLO Resources -- Pacific Northwest

Acknowledgements