The monument is in a transition zone of several vegetation communities. The monument was created from the acquisition of private land that had been farmed and logged altering the native vegetation mosaic. Results of monument vegetation surveys combined with information from federal land surveys show that a mosaic of forest, savanna, and prairie covered the monument. Prairie and savanna dominated ridges and south facing slopes. Forests pockets were likely found on north facing slopes and in the river floodplain.
Did You Know?
In the South Unit of Effigy Mounds National Monument, the Marching Bear Group of 10 bear mounds, three bird mounds and two linear mounds represent the best preserved group of effigy mounds present today from the Effigy Mound Culture.