SOIL WATER, DRAINAGE, AND IRRIGATION 213 



It is evident that dry farming requires much labor in order 

 to put the soil in proper condition for the production of a 

 crop. Even with these difficulties fine crops have been grown 

 by dry farming, and when we consider the extreme cheapness 

 of land in the dry-farming regions, the relative amount of labor 

 seems well repaid in results. It must be said that dry farming 

 is still somewhat in the experimental stage, and whether it is 

 to be extended to cover other large areas where there is scanty 

 rainfall cannot be safely predicted. In any event, there are 

 large areas of dry land which receive no rain, or practically 

 none, and these areas must look to some form of irrigation as 

 the means of securing the water needed to make them pro- 

 ductive. So far the limitations of irrigation are very great. 

 The quantity and availability of the water supply have thus 

 far limited irrigation to relatively small areas, though the 

 total acreage seems large. Whether the Great American 

 Desert is to be obliterated and become a most fertile region 

 is largely a question of quantity and availability of water. 

 There may be sources of water supply (deep wells or the 

 air) not yet within the range of practicability, but these are 

 for future developments. There is untold wealth in the soil 

 of the arid regions for those who can put a good supply of 

 water upon it. 



235. Reclamation of swamp lands. The opposite of arid 

 soils is found in such extensive areas as the undrained or 

 poorly drained everglade swamps of Florida, the Dismal 

 Swamp of Virginia and North Carolina, the swamps about 

 our inland lakes, both large and small, and the overflowed 

 areas along the lower stretches of our great rivers. The United 

 States Geological Survey estimates that in this country there 

 are over 100,000,000 acres of undrained swamp land, much 

 of which is drainable. Along the Atlantic coast alone there 

 are estimated to be over 3,000,000 acres of drainable soil. 

 Often this kind of soil is the most productive, when it is 

 properly drained. 



