Live Stock Breeders' Association. 253 



to the fact that the soil nitrogen has been drawn upon year by year 

 while the chief effect of the clover has been to extract phosphorus 

 from the soil for its own growth and for the use of succeeding 

 crops. 



There is another point to be considered in reference to nitro- 

 gen. On land that is capable of furnishing sufficient nitrogen for 

 even a 50-bushel crop of corn, the clover crop will undoubtedly 

 draw a third of its nitrogen from the soil and not more than 

 two-thirds from the air. Consequently, since two-thirds of the 

 nitrogen in the entire plant is removed in the tops, the roots and 

 stubble will leave no more nitrogen in the soil than the plant takes 

 from the soil. How then can we maintain the supply of nitrogen 

 in the soil? By plowing under clover or applying farm manure, 

 or by both of these means. 



If all the crops grown in the rotation are fed, including the 

 corn stalks, containing a total of 526 pounds of nitrogen from four 

 acres, and if three-fourths of this, or 395 pounds, are returned in 

 the manure, we have sufficient to replace the 386 pounds removed 

 in the corn and oat crops, and we may assume that the 160 pounds 

 removed in the clover came from the air. Of course, some addi- 

 tional nitrogen will be saved in the straw and stalks which are 

 used for bedding, as compared with the crops fed. 



How shall the grain farmer maintain the nitrogen in his soil? 

 Possibly this can be done by growing an additional legume catch 

 crop in the corn and plowing under everything produced except 

 the grains and the clover seed, preferably only one corn crop being 

 grown in the rotation. 



The problem of maintaining the nitrogen becomes easier if we 

 extend the rotation to include about two ears of pasture, using a 

 mixture of red clover, alsike, timothy and red top, instead of seed- 

 ing red clover, only, with the oats. In this case three-grain crops, 

 as corn, oats and wheat, or corn two years and oats one year, could 

 be grown during the six-year rotation, the farm being divided into 

 six different fields. 



In England and in other progressive agricultural countries of 

 Europe the value of feeding stuffs is commonly figured in two 

 ways : First, for the feeding value ; and second, for the fertilizing 

 value of the manure produced. 



Among the most successful and up to-date farmers in this 

 country these two values are also carefully considered. 



It is one thing to say that farm manure has a value, but quite 

 another thing to say what that value is or to what it is due. 



