156 . STATE HORTICULTURAL SOCIETY. 



Perhaps the reason for this acid condition is due to the rainfall and 

 loss by leaching, the deficiency in the material from which the soils 

 were formed and the removal by cropping. Lime is lost from the soils 

 that are cropped much more rapidly than from uucropped virgin soils. 



During the past season we have been carrjang on studies of virgin 

 and cropped soils, and here note the lime requirements. I have given 

 only two or three illustrations as follows: 



Increase in acidity of soils by cropping. 



Sandy Loam Soil From Lime Requirement, 



Kalamazoo County. lbs. per acre. 



Virgin 1,250 



Cropped 75 years 3,500 



Fine Sandy Soil From Lime Requirement, 



Van Buren County. lbs. per acre. 



Virgin 500 



Cropped 70 years 3,800 



Sandy Soil From Lime Requirement, 



Wexford County. ^ lbs. per acre. 



1. Virgin Not acid 



Cropped 20 years 2,250 



2. Virgin (Fine sand) 1,250 



Cropped 15 years 1,750 



Such differences are not due wholl}" to the removal of lime from the 

 soil by crops, but in addition there is usually an increased loss by leach- 

 ing of lime from cropped soils on account of the solvent action of the 

 roots and other changes taking place. 



The addition of stiible manure or commercial fertilizer will increase 

 this loss so Ave can say that any field under cultivation that is not re- 

 ceiving an occasional application of lime is turning toward an acid con- 

 dition. 



Now the next point concerns the variations in the results obtained 

 from the use of lime by difl'erent farmers. There are several reasons 

 for these diff'erent results, indeed, the action of lime in soils is quite 

 complex. First, we must find out just what lime does when it is applied 

 to soil — what conditions it brings about.' Undoubtedly, organic matter 

 will be decomposed more rapidly when there is suflicient amount of lime 

 present. In some of our soils vegetable matter exists in rather advanced 

 stages of decay, which means the decomposition processes are slowed 

 up, but an application of lime may speed up the rate of decomposition 

 of such material, therefore, it will increase the amount of available 

 nutrient for your crops. In fact, everybody knows that decaying vege- 

 table matter in soils results in more available mineral matter for croi)s. 



Furthermore, we know of some cases, at least, where the ai)plication 

 of lime will loosen or unlock certain i)hosphates and potash compounds. 

 This has been determined by the analyses of plants growing oti treated 



