UNIVERSITY OF CALIFORNIA PUBLICATIONS 



IN 



AGRICULTURAL SCIENCES 



Vol. 1, No. 9, pp. 275-290, pis. 1-4 June 9, 1915 



NEW EXPERIMENTS ON ALKALI SOIL 



Hii 



TREATMENT «AkJ>ei^. 



(Preliminary Report) 



BY 



CHAELES B. LIPMAN and LESLIE T. SHARP 



The presence of "alkali," denoting water-soluble salts in con- 

 siderable quantities in soils, has long been one of the problems 

 of soil management in arid regions from the point of view of 

 the practical as well as that of the scientific man. While soluble 

 .salts like magnesium and calcium sulphates, and chlorides as well 

 as, in some cases, nitrates of the alkalies and alkali earths and 

 other soluble compounds frequently occur with them, the salts 

 which usually are found to cause injury in alkali soils are sodium 

 chloride, sodium sulphate, and sodium carbonate. It is unneces- 

 sary to go into detail here on the specific effects of every one 

 <if these salts. Suffice it to say, that in general the damage 

 is caused by these salts through corrosion of living plant sub- 

 stance, through plasmolysis of plant cells owing to injurious 

 o.smotic influences, and through effects on the physical, chemical, 

 and bacteriological constitution of the soil which result in poor 

 aeration, poor moisture supply, improperly balanced chemical 

 composition of the soil solution, and in impairment of those 

 bacteriological activities necessary to insure an available supply 

 of plant food substances, particularly of the nitrogen variety. 



Alleviative measures in vogue to date in dealing with the 

 alkali problem as it affects crop production have been, in general, 

 of two classes. The first class is that concerned with the removal 

 of alkali salts from the affected soils by flooding, accompanied 

 by underdrainage by natural or tile drain methods. The second 



