l62 KNAPP METHOD OF GROWING COTTON 



The problem of soil fertility and how to 

 maintain it has been a very vital one to all 

 nations. The earliest agricultural literature 

 mentions the use of manures and other refuse 

 to make the soil more productive. In all 

 the old countries the question of keeping up 

 the soil fertility has been successfully met. 

 This is evidenced by their being able to feed 

 from the same lands the constantly increasing 

 population. There are lands in some of the 

 European countries that are producing, after 

 more than one thousand years of cultivation, 

 larger crops than ever before. The density of 

 the population and the lack of room for expan- 

 sion make it necessary to conserve all the re- 

 sources, and especially that of the soil. 



In America there has been a very different 

 situation. With a sparse rural population and 

 a seemingly unlimited expanse of fertile virgin 

 soil, the question of caring for or conserving 

 the soil was lost sight of for a long time. It 

 was not until recently that the constantly 

 decreasing yield per acre of our soils was 

 seriously considered. While the abuse of farm 

 lands, idle fields, and tenantless homes are 

 noticeable all over the country, these are 



