168 



SOIL PHYSICS AND MANAGEMENT 



The following table gives data from Purdue Station and illus- 

 trates the value of different amounts : 



Average Value of Increase for Manure Per Crop and Per Ton for Twenty-three 



Years, 1890-1912 1 



(d) Methods of Applying Manure. For an application of 

 manure to be most effective it should be evenly distributed and 

 then thoroughly mixed with the soil. It is very difficult to accom- 

 plish the first by hand spreading. There will almost certainly be 

 large chunks of manure alternating with bare spots. The manure 

 spreader (Fig. 83) is indispensible for this purpose. It tears the 

 manure to pieces, scatters it evenly and permits of smaller applica- 

 tions. The same amount of manure covers a larger area and, as 

 seen from the above table, gives it a higher value per ton. The 

 mixing of the manure with the soil may be readily accomplished 

 by the disk. This is not so important unless a crop is to follow 

 soon, as in the case of spring plowing for corn or summer plowing 

 for wheat. It is especially desirable for coarse manures which when 

 plowed under interfere with capillary movement. 



The manure should be applied as soon as possible after being 

 produced, since there is less loss when in or on the soil than if left 

 in the lot or even the shed (Fig. 82). Some farmers prefer well 

 rotted manure, but there is too much loss in the process of decay to 

 allow this to go on in any other place than in the soil. Weight for 



