Interpolated General Land Office fire occurrence notes were used to determine the spatial extent of pre-European settlement fires for 26 counties in northern lower Michigan using ordinary kriging with probability output. Best fit of a surface was achieved using a spherical model with a lag distance of 860 meters, an angular tolerance of 45 degrees, and consideration of anistropy. The interpolated data were associated with Land Type Associations to determine fire rotation and occurrence intervals for pre-European and modern day fires. The results show that modern day fire suppression efforts have curbed the size and frequency of fires.