Fire History in the Cherokee Nation of Oklahoma

The role of humans in historic fire regimes has received little quantitative attention. Here, we address this inadequacy by developing a fire history in northeastern Oklahoma on lands once occupied by the Cherokee Nation. A fire event chronology was reconstructed from 324 tree-ring dated fire scars occurring on 49 shortleaf pine (Pinus echinata) remnant trees. Fire event data were examined with the objective of determining the relative roles of humans and climate over the last four centuries. Variability in the fire regime appeared to be significantly influenced by human population density, culture, and drought. The mean fire interval (MFI) within the 1.2 km² study area was 7.5 years from 1633 to 1731 and 2.8 years from 1732 to 1840. Population density of Native American groups including Cherokee was significantly correlated (r = 0.84) with the number of fires per decade between 1680 and 1880. Coincident with the Removal of the Cherokee and other native peoples from the eastern United States and immigrations into northeast Oklahoma, the MFI decreased to 1.8 years. After 1925 fire intervals were considerably lengthened (MFI = 16 years) due to fire suppression and decreased fire use until the recent prescribed burning by The Nature Conservancy. Many of the historic fire years that were previously shown to be synchronous across Missouri and Arkansas during drought years were also fire years at this site. Overall the frequency of fires was weakly associated with drought compared to human population density.