FOIi liKTTKR CHOPS 13 



returniiif^: it in farm manure, or by plowing'" under green manures 

 corn stalks, straw, and other coarse products, and by adding- 

 phosphate and limestone. 



With a good supply of plant food stored in the soil, then the 

 thing of greatest importance in the business of farming is 

 the liberation of sufficient plant food during the growing season 

 to meet the needs of maximum profitable crops. While thorough 

 tillage aids in this process, by far the most effective and practical 

 means within the farmers' own control for liberating plant food 

 from the soil's supply or from insoluble material, as natural rock 

 phosphate which may have been applied, is decaying vegetable 

 matter. 



The farmer or landowner whose farm practice includes these 

 two points: that is, (1) plenty of plant food stored in the soil, or 

 added to it when necessary, and (2) plenty of decaying organic 



A -wasteful pra.ctice 



matter to liberate plant food for the crop needs, will have in 

 operation a system of agriculture which is permanent. 



The one point is no more important or essential than the 

 other. The man who tries to maintain the fertility of his soil 

 and who hopes to continue to grow large, profitable grain crops 

 without the use of legume crops or plowing under farm manures 

 or coarse products, but who uses high-priced soluble manufac- 

 tured commerical fertilizers, is unwise, and ultimately his land 

 will probably follow the history of the lands which have been 

 practically ruined by such practice in the eastern states. 



On the other hand, the man, who thinks the productive 

 capacity of the ordinary prairie land in the humid regions of 

 Central United States can be permanently maintained merely 

 by the use of clover in crop rotation, is also unwise, for this is 

 absolutely impossible. So far as phosphorus and other minerals 

 are concerned, the use of clover in crop rotation is one of our 

 most effective means of liberating those plant food elements 

 from the soil so that thev mav be removed in subsequent grain 



