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HISTORICAL VEGETATION Based on interpretation of the 1850s public land survey(PLS),in which the dominant tree (bearing tree) and other vegetation was recorded at every one-mile interval,the boundaries of the Bailey Point Nature Preserve lie within what would have been oak openings and barrens in pre-European settlement times (Figure 6). The property lies on the border of historical floodplain forest and near areas of prairie as well.The land cover type in this region was mosaic of different habitats ranging from oak openings and floodplain forests,to prairie,big woods forests,and aspen-oak woodlands.The most common land cover type of the region was oak openings and barrens,which we today would call savanna. Savanna is an area of scattered trees,primarily bur oak,with areas of open prairie between them. Prairie was an area dominated by mixed height grasses and forbs (wild flowers),with patches of shrubs and very few to no trees.The difference between prairie and savanna is created by frequency and intensity of fire. Generally,frequent fire (every 2 to 5 years) will result in prairie,while slightly less frequent fire (3 to 8 years) will result in savanna. Today,the south end of the Bailey Point property is classified as floodplain forest. However,whether trees historically lined the entirety of the river channels is unclear.While much of the current floodplain forest areas were likely floodplain forest in pre-settlement times, areas of the river may have been lined with savanna or prairie vegetation. Prairie and savanna grasses could have grown right up to the channel,perhaps forming lips over the banks and stabilizing the bank slopes,as currently occurs in other neighboring areas. Bearing trees were noted by the 1850s PLS surveyors to help identify each section of land. If no trees were in the section,that was also noted. No bearing trees were recorded within the Bailey Point boundary,though two were identified on the adjacent WHHCA. Both trees were identified as "bur oak", providing further evidence that this area was likely a mix of prairie and oak savanna vegetation. Note that the soils data and the pre-settlement vegetation data concur: soils are prairie soils and pre-settlement vegetation shows prairie and savanna land cover. Historical aerial photos can also help us reconstruct what the vegetation was like during the last 75 years. The oldest aerial photo that we have for this site is from 1939 (Figure 7),and sheds light on past conditions of the area. At that time,the present day cropland was being cropped,but some of the natural areas of the property were much more open than present conditions. Many of the floodplain forest areas had a sparser canopy and looked more similar in structure to vegetation found in a savanna-type landscape. While a thin strip of tree cover lines the majority of the riverbanks, some areas were relatively open right up to the rivers' edge. Moreover, in what is now some of the larger floodplain areas,it is easy to see the more open nature of the habitat,with trees interspersed with more open grassy areas.This is especially true on the northeast side of the property,where a small Friends of the Mississippi River Bailey Point Nature Preserve NRMP 23