EXPERIMENT STATION BULLETINS. 315 



LIME FOR AGRICULTURAL PURPOSES. 



Circular No. 11. 



A. J. PATTEN AND J. A. .TEFFERY. 



A great deal of interest has been exhibited during the past year in the 

 use of lime for agricultural purposes. This circular is issued to supply 

 the demand for inforaiation on this subject but the authors do not 

 wish it to be understood as an unqualified recommendation for the use 

 of lime. It is undoubtedly true that there are spoils in the state that 

 will be benefited by the use of lime just as there are soils that will be 

 benefited by the use of some form of commercial plant-food but it is 

 equally true that there are many soils that would receive no appreciable 

 benefit from the use of lime. Up to this time no reliable laboratory 

 method has been devised by which this information may be obtained. 

 The litmus paper test has been relied upon for the purpose but it is 

 very untrustworthy since with soil solutions having very finely divided 

 soil particles in suspension the paper is often reddened, while the solu- 

 tion, freed from the soil particles, gives an alkaline or neutral reaction. 

 This phenomenon is explained perhaps, by the fact that the soil particles 

 have a great absorbing power, and the blue litmus dye being more 

 soluble than the red litmus dye, is absorbed leaving the jjaper red. 

 Perhaps the most reliable indicator of the need of lime is tlie failure 

 of clover to make a satisfactory stand when all other conditions are 

 favorable. 



The practice of using lime is almost as old as agriculture itself. The 

 Chinese were probably the first to use lime on the soil ; it was also used by 

 the Romans and by them the practice was introduced into England and 

 France. In England the practice of marling the soil has been followed 

 for centuries, and often with marked results. The first mention of lime 

 in connection with American agriculture is found in the contributions 

 of Ruflin in the "American Farmer" in 1818. Although lime has been 

 used more or less extensively by the farmers of the United States for 

 the i^ast century, its action upon the soil is not generally understood. 

 Lime should never be considered as a fertilizer in the same sense that 

 barnyard manure or commercial fertilizers are. It can never take the 

 place of these materials but should be used in connection with them. 

 Generally speaking, all soils contain a sufficient amount of lime to meet 

 the plant-food requirements of crops for this element for all time, con- 

 sequently the benefits from lime are shown in another way. It is usually 

 spoken of as an "amendment" or "modifier" because it is capable of 

 correcting conditions that may be inimical to the best growth of plants. 



Lime may act upon the soil in three ways, viz. : chemically, physically 

 and biologically. 



Chemical Action. — Lime acts upon the insoluble potash compounds in 

 the soil changing them into forms available as plant-food. This action 



