SOILS OF THE EASTERN UNITED STATES AND THEIR USE XL. 



MARSH AND SWAMP. 



In the soil classification of the Bureau of Soils the term " Swamp " 

 is used to designate all areas which in their natural condition are 

 too wet for the production of any crop. Such areas are usually 

 covered with standing water for much or all of the time. Swamps 

 are covered with a great variety of native vegetation, consisting 

 chiefly of water-loving grasses, reeds, shrubs, and trees. 



The word " Marsh " is used by contrast to designate low, wet, tree- 

 less areas, usually covered by standing water and supporting a growth 

 of coarse grass and rushes. The Marsh is subdivided into two classes. 

 The first of these is the Tidal marsh, where broad stretches of low- 

 lying and practically treeless land along the coast are subjected 

 to inundation by the rising tide. The other class consists of the 

 fresh-water areas in the uplands or near the heads of tidewater 

 estuaries where fresh water is backed up over the marshland by 

 each rising tide. 



During the progress of the soil-survey work there have been 

 encountered 21,184 acres of Marsh, 588,544 acres of Tidal marsh, and 

 1,745,512 acres of Swamp. This constitutes a total acreage of 2,355,- 

 240 acres of all classes of swamp land. It is probable that a total area 

 of approximately 60 million acres of these undrained lands exist in 

 the eastern part of the United States in addition to approximately 

 15 million acres of Meadow, which occurs in swampy positions along 

 streams. 



CONTRAST WITH OTHER TYPES. 



The areas of Marsh and Swamp might possibly be confused with 

 Meadow. They differ from Meadow, however, in that they are 

 either permanently wet or are covered intermittently by the tide. 

 By contrast the areas of Meadow, which lie chiefly along alluvial 

 flood plains, are subject to inundation at indefinite intervals. The 

 meadowlands are usually overflowed with the annual rise of the 

 streams which they adjoin. The Marsh and Swamp, however, almost 

 always consist of areas where water accumulates either through the 

 more or less permanent obstruction of drainage channels or through 



the seepage of water from higher lying areas. 



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