BIG SPRING PRAIRIK. 21 



feet higher than the level of prairie just north of Carey, 

 and about ten to twelve feet higher than the lower end 

 of old lake. Consequently, if the water was deep enough 

 for canoeing upon the divide, and if the general level 

 and slope were then as now, the depth of water just 

 north of Carey must have been about eight feet and at 

 the lower end of old lake about ten feet. But this is 

 impossible, as it would have flooded the present site of 

 Carey, and would have been drained into Spring Run. 



Either the statements are false; or the divide has 

 been built up considerably within the last seventy years 

 and the general level of prairie just north of Carey and 

 of lower end of lake are considerably lower than form- 

 erly. These last two phases will be further discussed 

 under Drainage of Prairie, past and present and its ef- 

 fect upon general level of same. 



It was impossible to get any reliable scientific data 

 in regard to flora of prairie in the earlier part of the 

 nineteenth century; but, according to statements of 

 the pioneers, cattails, reeds, bulrushes, poison sumach 

 (popularly called "poison shumake''), boneset, wild 

 sun-flowers, and sedges were more abundant; while 

 willows occurred only along the border of prairie or 

 marsh and on a few isolated spots which were slightly 

 higher than the general level. The wild rose occurred 

 less frequently than at present; and the elderberry, 

 which became so common in late years did not occur at 

 all upon the prairie until artificial drainage was put 

 into operation. Before this, it was one of the common 

 plants on certain portions of the ridges. 



Large areas of sedges, known as marsh grass by 

 the old settlers, were mown for the hay. As no areas 

 of any size were available for this purpose in late years, 

 the almost pure sedge societies have been supplanted 

 by other more-varied plant societies. 



Although the Big Spring Prairie was in reality a 

 marsh, perhaps similar to the Skokie Marsh in northern 



