j •*■ LIL5I. 



New YJoRK Agricultural Experiment Station. 125 



early spring, there is likely to be very little loss of nitrogen. On a 

 loose soil, there may be loss from leaching, if the manure is spread 

 long before the crop is put into the soil ; but in average experience, 

 this is not a])t to be considerable. This method has the advantage 

 of uniform distribution as the liquid portion is evenly by degrees 

 mixed with the soil. When the manure is leached of its soluble 

 nitrogen compounds, it does not decompose so readily. On this 

 account it is well, in case of light or porous soils, to plow the manure 

 in as soon as sj^read. 



In regard to the depth at which manure should be plowed in, 

 it is safe to say that in very compact soils, the depth should not be 

 greater than 4 inches, while in lighter soils the depth may be 

 increased. It is important that the manure be near enough the 

 surface to allow access of sufficient moisture and air, in order that 

 decomposition may not be too much delayed. 



(c) Applying in Roiu. 



This method has the advantage of placing the manure where it 

 will reach the plant most quickly and of enabling one to use smaller 

 amounts than in broadcasting. It is especially applicable for forcing 

 some garden crops. Rotted manure gives good results when used 

 this way. 



XII. The Arithmetic of Fertilizers. 



When we desire to know the amount of nitrogen, potash and 

 phosphoric acid contained in different forms and materials or to 

 make up formulas from materials of known composition, or to de- 

 termine the commercial value of any single material or of any 

 mixture, it is necessary to go through various mathematical pro- 

 cesses, most of which are comparatively simple and easily under- 

 stood. So many inquiries have come to us on questions involving 

 simple calculations, that it is thought advisable to present a some- 

 what systematic consideration of some of the more common prob- 

 lems met with. Some calculations, which it might be desirable to 

 use at times, involve more knowledge of chemistry than can be 

 given in a simple treatise of this kind. 



Before taking up a consideration of the mathematical details we 

 will make a brief explanation of the different terms used in ex- 

 pressing fertilizer guarantees and analyses, because an accurate 

 knowledge of such terms is important, especially in making com- 

 mercial valuations and in planning formulas. 



