MANAGEMENT OF SPECIAL SOILS 279 



alkali down to lower levels and to dilute the solution in 

 the surface soil, thus frequently making profitable crop 

 growing possible. 



On irrigated land, flooding and under drainage to 

 wash out the soluble salts and carry them away in the 

 drainage water is frequently practised. When the alkali 

 contains sodium carbonate, land plaster or ground 

 gypsum may be applied. This changes the black alkali 

 to white alkali, a less harmful form and one that may 

 more easily be removed by drainage. The removal of 

 alkali by mechanical means is sometimes practised on 

 high-priced land. Shutt points out also that on certain 

 types of alkali or those consisting largely of magnesium 

 sulphate (Epsom salts) the application of lime or marl 

 before irrigation and drainage is beneficial. 



234. The Use of Alkali-Kesistant Crops.— None of the 

 important field crops can be grown where the alkali is 

 strong. Rye and barley are reported to be more resist- 

 ant to alkali than the other cereals. Among wheats the 

 macaroni varieties are said to be the best. Members 

 of the beet family are the most resistant root crops for 

 this type of soil. The legumes as a class do not do well 

 on alkaline areas, although sweet clover is reported to be 

 alkali-resistant. The forage crops or those grown for 

 hay or feed rather than for seed are generally the best 

 to grow on alkali land. "Western rye grass and brome 

 grass are commonly sown and used either for hay or 

 pasture on soils of this nature. 



Kearney in a summary of his studies on the alkali 

 resistance of crops states in Bulletin No. 44 of the 

 United States Department of Agriculture that "most 

 field crops cannot be profitably grown when the 

 quantities of white alkali salts (sulphates, bicarbonates 



