CHAPTER XLIX. 

 SOME GENERAL CONCLUSIONS. 



1. Commercial fertilizers are simply plant food, in a concentrated form 

 and more or less immediately soluble condition, and are not stimulants any 

 more than stable manure is a stimulant. 



2. Lime and land plaster may be regarded as stimulants from the fact 

 that, although plant food to some extent, they have a further office as reagents 

 in bringing about changes in matter already in the soil, and bringing into 

 use matters otherwise unavailable to plants. Hence if used with the idea that 

 they are manures and will make the soil rich, the result will finally be to ex- 

 haust the soil of some matters essential to plant life, while if their office is 

 properly understood they are the most efficient agents in the maintenance of 

 the fertility and productiveness of the soil. 



3. While they are not to be regarded as mere stimulants, commercial 

 fertilizers, used as a constant reliance for the getting of the same crop from 

 the same soil year after year, will finally result in a condition of the soil in 

 which it will no longer respond to the application of the fertilizers as it once 

 did, largely because of the mechanical condition of the soil and the using up 

 of the humus ; one of the most efficient agents in making the fertilizers avail- 

 able to plants. 



4. While the application of a fertilizer mixture to every crop planted 

 or sown may show an increase in the crop, such a course is seldom profitable, 

 and the indirect accumulation of fertility through the agency of the legumes, 

 aided by commercial fertilizers, will generally give more profitable results 

 than the application of fertilizers direct to the sale crop. In other words, 

 the place to use the f ertilzer for our ordinary farm crops is in the promotion 

 of the growth of the legumes that make food for animals and food for the 

 soil at the same time. 



5. One crop farming, or, rather, planting the same soil year after year 

 with the same crop, and applying commercial fertilizer for the purpose of 

 getting a crop, is merely gambling on the chances, and like every other kind of 

 gambling results in final disaster to the gambler. 



6. The soils of the South have lost fertility faster through the leaving 



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