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We used pollen and charcoal in lake sediments to ask how coarse vs fine textured soil and the abundance of fire breaks influenced the response of oak-and pine-dominated ecosystems to the climatic changes of the past 2000 years. We hypothesized that sites dominated by the most xeric soils would exhibit greater stability in community composition over time than would sites on less xeric soils. This hypothesis predicts that vegetation on the less xeric sites will have changed more when the climate became drier, but the most xeric sites would have had relatively stable jack pine vegetation because they would be resistant to invasion by species less tolerant of poor soils and drought. The resistance of xeric sites to invasion would be strengthened by stabilizing vegetation-fire feedbacks of jack pine. Our second hypothesis was that sites surrounded by fewer lakes and wetlands would exhibit greater stability in community composition than sites in areas with more lakes and wetlands. We predicted that more frequent fires would promote the maintenance of jack pine vegetation and its stabilizing vegetation-fire feedbacks on sites with fewer fire breaks. We tested the first hypothesis by comparing the vegetation and fire histories of sites that differ in soil drainage, but are matched in their abundance of fire breaks, and the second hypothesis by comparing sites that differ in their abundances of lakes and wetlands but have similar soil drainage characteristics.