Hardwood forest and prairie communities have been altered over centuries by different land use requirements (Knopf and Samson 1997; Johnson et el. 2002; McShea and Healy 2002). For many National Park Service (NPS) units, communities in altered conditions existed prior to NPS status. For some parks, it is the very change in the landscape that warranted NPS designation, as is the case for Effigy Mounds National Monument, Iowa (EFMO). The park represents nearly 2000 years of mound building activity and associated human presence in the driftless area of northeastern Iowa along the Mississippi River.