Lime, Its Value and Importance 1G81 



is largely dependent upon this action. These bacteria, and conse- 

 quently the nodules, do not develop in acid soils. Hence, through 

 the failure of the legume (other classes of plants do not possess 

 this function) no nitrogen is added to the soil. In fact the supply 

 is being diminished in many soils. Organic matter containing 

 nitrogen, such as stable manure and clover sod, must go through 

 a certain kind of decomposition before the nitrogen so contained 

 becomes of use to plants as food. In the absence of sufficient lime 

 to overcome all acids in the soil as fast as they are formed, this 

 process is interfered with and the nitrogen in the stable manure 

 or other organic fertilizer may be wasted instead of being made 

 into plant food. Between these two difficulties, the failure of 

 legumes and the unfavorable fermentation in acid soils, it is 

 indeed hard to keep up the nitrogen supply in some lands. 



The most beneficial effect of lime is promotion of the growth 

 of leguminous plants. This results in building up the nitrogen 

 supply and the general fertility of the soil. It is to be noted 

 that this soil improvement is accomplished principally through 

 leguminous crops, and if rotations are not so planned as to ad- 

 vantageously include them, the end and aim of liming — soil 

 improvement — is defeated. The blind application of lime is 

 of very little use. 



Tlie beneficial effects of lime usually do not appear at once, 

 except on legumes. The latter grow better almost immediately, — 

 if the soil needs lime — develop more nodules and gather more 

 nitrogen. The benefit to other crops evidently cannot begin to 

 show until at least one leguminous crop has followed the applica- 

 tion of lime, and been plowed under, either in its entirety or the 

 stubble and roots. In all cases, according to the Indiana Experi- 

 ment Station, " the promotion of the growth of legumes is the one 

 effect which above all others justifies the use of lime." 



CARE IN ITS USE 



It is to be emphasized that no form of lime should be mixed or 

 used directly with stable manure, notwithstanding the claim of 

 many manufacturers of limestone. Neither should lime materials 

 be combined with acid phosphate nor with fertilizers containing 

 it. Materials containing organic nitrogen, such as dried blood and 

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