COTTON 121 



diminutive returns in seed and lint. By a de- 

 ficiency is meant, in this case, an insufficient 

 amount of plant food available for the use of the 

 plants. 



Really, as we have already seen, there is no such 

 thing as worn-out cotton soils. There are poor 

 cotton soils, unproductive cotton soils, infertile cot- 

 ton soils, but they are so because of improper man- 

 agement; because the humus has been destroyed; 

 shallow plowing has been followed; plant food has 

 been lost or locked up. 



Tillage and humus and these alone unlock 

 the door to this treasure-house of old Mother 

 Earth. The addition of nitrogen, phosphorus and 

 potassium in chemical forms is only a temporary 

 arrangement to make better crops for the time 

 being. No permanent improvement of the soil will 

 result unless tillage and an abundant amount of 

 humus become the basis of such improvement. 

 Chemical fertilizers are to be used, therefore, as 

 supplementary helps, rather than as primary con- 

 ditions. 



We are now ready to consider the feeding de- 

 mands of the cotton plant in reference to the forms 

 of plant foocj usually purchased nitrogen, phos- 

 phorus, and potassium. 



But first, let us divide the cotton plant into its 

 parts that we may clearly know the relative quan- 

 tities of each. 



PARTS OF AN AVERAGE COTTON PLANT 



Part Per cent. 



Roots 8.80 



Lint 10.56 



Bolls 14.21 



Leaves. , ,20.25 



