338 Missouri Agricultural Report. 



GOOD SOIL. 



The second great group of factors influencing the yield of 

 corn are those pertaining to the soil. These are many in number 

 and varied in character and it is possible in the space of this 

 paper to consider only the most important. It is obvious that 

 to produce a good crop of corn one must have productive soil. 

 The productiveness of many soils in ttie corn belt has been 

 materially lessened by mismanagement and poor businesslike 

 methods of farming, and to a vast majority of corn growers in 

 this region the first step to take in increasing their yield of corn 

 is to make their soil better. Likewise to the others one important 

 consideration at least is to keep their soils productive, for it is 

 much easier to maintain the productiveness of soils than it is to 

 build up the fertility of worn lands and make a living on them 

 at the same time. I want to briefly call your attention to some 

 things a man can do to accomplish these ends. 



The Cropping System. — One of the most important factors 

 influencing the yield of corn is the cropping system, which has a 

 marked influence upon the fertility of the soil. The gross returns 

 from the corn crop are not great enough to justify the expense of 

 heavy applications of fertilizers and manures that it is possible 

 to make with tobacco, potatoes, tomatoes and other special or 

 truck crops, and we must, therefore, depend largely upon the 

 cropping system to maintain the yield of the corn crop. It is, 

 of course, profitable to use manures and fertilizers on the corn 

 crop as will be indicated later, but to be most efficient it is neces- 

 sary that these be used in connection with a systematic rotation 

 of crops. In this connection let us consider briefly the history 

 of the development of cropping systems in America. When 

 any new section is settled up it has been our practice to follow 

 for a number of years what we might term a one-crop system: 

 In the south cotton, in the middle west corn and in certain parts 

 of the west wheat has been the chief crop grown. Such a plan 

 usually continues with very little if any variation for forty or 

 fifty years, or until the land begins to fail. Then the farmer 

 begins the alternation of crops such as corn and oats, corn and 

 wheat, corn and tobacco, or corn and grass, which we may term 

 a two-crop system. This is not carried out systematically, but 

 since most farmers recognize the importance of simply changing 

 crops on a field it is looked upon as a means of maintaining 

 yields. This plan likewise usually continues for some thirty-five 



