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in the United States contains so much alkali as to be unfit for 

 cultivation to any but the most alkali-resistant crops. 



Man}- attempts have been made to free land from alkali by the 

 application of gypsum, stable manure, and other substances, or by 

 washing out the salts by flooding the land and quickly draining the 

 water off the surface. None of these has proved of an}^ permanent 

 benefit to land strongly impregnated with alkali. After careful 

 investigation the Bureau became convinced that the only way perma- 

 nently to reclaim alkali land where the ground water is near the sur- 

 face is by underdrainage and flooding. This conviction was strength- 

 ened when the Bureau's expert in alkali-land reclamation made a trip 

 to Egypt and Algeria during the summer of 1902 and investigated the 

 work being done there by English and French engineers. In the lower 

 Nile Valley they have reclaimed land so salt that it contained 380 tons 

 of salt per acre to a depth of 3 feet. 



The reclamation of alkali land by underdrainage and flooding is 

 purely a mechanical process. The first step is the installation of a 

 complete drainage system. This may consist of deep open ditches, or 

 of box or tile drains. Since hard burnt tile have been found the most 

 economical means of draining wet lands, their use is generally to be 

 recommended. The drain tile should be laid from 4 to 5 feet below 

 the surface, the distance apart of the rows of drains depending upon 

 the character of the soil. In an impervious clay gumbo or adobe soil 

 the tile should be placed at least 100 feet apart, while on coarse, sandy 

 soils they may safely be placed upwards of 300 feet apart. The land 

 is then carefully leveled and "checks" thrown up to keep the water on 

 the land. The land is then flooded to a depth of several inches. The 

 drains carry off the underground or seepage water as fast as it rises to 

 their level, thus breaking the connection between the water table and 

 the soil surface. The flooding dissolves the salt or alkali in the soil 

 above the drains and carries it down and out through the drains, 

 thereby permanently freeing the soil to the depth of the drains from 

 injurious accumulations of alkali, as well as seepage water. 



In order to demonstrate the efficiency of this method of reclamation, 

 the Bureau of Soils is underdraining and flooding tracts of land near 

 Salt Lake City, Utah; Fresno, Cal.; North Yakima, Wash.; Tempe, 

 Ariz., and Billings, Mont. At the first two places named, where the 

 reclamation work has been carried on for some time, the lands have 

 been so thoroughly freed from alkali that good crops were grown dur- 

 ing the season of 1901, thereby proving that drainage and flooding will 

 reclaim the worst of alkali lands. The results of the work at the other 

 places named have been very satisfactory considering the short length 

 of time the work has been carried on. 



