Ecological Impacts of Anthropogenic Fire in Southwestern Ohio, USA, Documented from Public Land Survey Records from 1802 and 1803

Public Land Survey System (PLSS) data collected in 1802 and 1803 were analyzed to evaluate the impacts of anthropogenic fire on pre-Euro-American settlement plant communities within a 50,193 ha (194-square-mile) study area east of what is now Dayton, Ohio. Surveyor data were converted to digital point, line, and polygon files using ArcMap software and mapped with some interpolation based on contemporary GIS data layers including topography, soil moisture, soil type, and Quaternary geology. Sixty-one percent of the study area was covered with woody and non-woody plant communities that are known to be shaped and/or maintained by long-term exposure to surface fires of varying intensities and frequencies: oak-hickory forest, oak woodland, oak savanna, oak barrens, and mesic prairie. Prairies and barrens were concentrated adjacent to the corridors of the Mad River and the Little Miami River and their major tributaries, while oak woodlands were concentrated in adjacent uplands. Oak-sugar maple forest covered an additional 29% of the study area, a community that was interpreted to be pyrophilic oak forest transitioning to mesophytic/ pyrophobic forest in the long-term absence of fire.