222 Fertilizers 



are favorable for the rapid change of the nitrogen in mate- 

 rials of good quality, like blood, concentrated tankage, 

 or cotton-seed meal, into nitrates. The amounts of 

 nitrogen needed would, under ordinary conditions, be sup- 

 plied by 100 pounds of high-grade blood, or 200 pounds 

 of cotton-seed meal, or by deriving equal parts of the 

 nitrogen from nitrate of soda and tankage. Other 

 changes are also required according to the cropping system. 

 In the rotation mentioned above corn follows a timothy, 

 which, if properly top-dressed each spring, supplies a large 

 amount of organic matter, and fertilizer may be used in 

 smaller quantity, and a smaller amount, especially of 

 the more slowly available nitrogen, may be included in 

 the mixture. The same is true if a rank leguminous cover- 

 crop is plowed under or if the ground is heavily manured. 

 If corn is grown for grain one year and silage the next, a 

 more abundant application should be made the second 

 year ; 20 pounds of nitrogen, 30 of phosphoric acid and 40 

 of potash is none too liberal. 



Whatever the practice of cropping, in this matter of 

 fertilizing, it must be remembered that weeds appropriate 

 plant-food quite as readily as the corn, wherefore in order 

 to obtain the best results from the fertilizers added, clean 

 cultivation should be practiced. 



Oats. 



For the oat crop that follows corn, and which makes 

 its best growth early in the season, before nitrification 

 is rapid, quickly available forms of nitrogen are very 

 desirable; and inasmuch as the oats require an abun- 

 dance of phosphates, a fertilization with phosphoric 

 acid is also essential. Hence, fertilizers consisting of 

 mixtures of nitrate of soda and superphosphates have 



