6 SOILS OF THE EASTERN UNITED STATES. 



direction of marine currents. No additional material is being added 

 to such deposits from the very nature of their origin. They are com- 

 pleted soils and only lack the minor alterations of better established 

 drainage. 



Thus not all overflow or swampy lands are mapped as Meadow and 

 only a small proportion of the poorly drained lands of the eastern 

 United States may be so classed. 



SURFACE FEATURES AND DRAINAGE. 



Areae of Meadow of varying size are found along the banks of 

 almost all streams at some points in their courses. Even streams 

 which have their sources within mountainous regions, where they are 

 active in the erosion of their banks and beds, frequently flow through 

 expanded sections of their courses where more rapid erosion through 

 soft rock or the obstruction formed by some harder stratum holds 

 back the water and causes the temporary deposition of the sediment 

 on its way to the sea. Within the middle courses of the great majority 

 of the longer streams there are areas where the stream spreads out 

 over more level territory or where it has built broad bottoms between 

 the higher, bounding walls of the stream way. These areas are most 

 frequently occupied by broad stretches of "first bottom" which are 

 overflowed during the spring freshets, but are partially drained and 

 productive throughout the balance of the year. These bottoms may 

 be continuous upon both sides of the larger streams or they may exist 

 only upon alternate sides as the stream swings its channel from bank 

 to bank, meandering through a flood plain of low gradient. 



The meadowlands always lie below the level of the adjacent uplands 

 In some cases the landward walls rise to elevations of many feet with 

 a sheer slope. In other instances, where the stream has cut no pro- 

 nounced channel, the Meadow gradually merges into the better 

 drained upland soil. Every variation between these extremes may 

 exist. 



The surface of the meadow deposits is usually nearly level so far as 

 any marked changes in contour or elevation are concerned. There is 

 usually a gentle slope downstream, according to the gradient of its 

 channel, which marks the fact that the surface of the overflow lands 

 is maintained at about a constant elevation above the normal water 

 level of the stream. This is a feature of meadow deposits along 

 streams as distinguished from small areas bordering some of the 

 smaller lakes which possess a nearly flat surface, slightly above the 

 lowest level of the sheet of water. A nearly level surface also marks 

 the meadowlands which have been formed in the delta portions of the 

 stream beds as distinguished from the midstream deposits made before 

 the stream emerges from higher-lying territory to the region of its 

 final soil deposition before entering the sea or inland waters. 



