222 COTTON CULTURE 



is profitably cultivated has been considerably extended. It is in 

 the northern section of the cotton belt that the use of fertilizers is 

 relatively greatest. 



Need of Fertilizer for the Cotton Plant. The cotton plant makes 

 only a slight draft on the fertility of the soil. It is a delicate feeder, 

 being in this respect much like wheat. The production of a bale of 

 cotton weighing 500 pounds removes from the soil only about as 

 much plant food as is contained in the grain alone of a 40 bushel 

 crop of corn or of a 60 bushel crop of oats. Accordingly, a given 

 amount of plant food, when transmuted into cotton, produces a 

 crop twice or three times as valuable as when transmuted into corn 

 or oats. 



But while the cotton plant uses only a small amount of plant 

 food, it requires this in a readily available form. It has not an 

 extensive and vigorous root system like that of corn or of oats, and 

 hence it has not like these plants the power to draw heavily from 

 the soil. A part of its food must, therefore, be artificially supplied 

 in an easily soluble form. 



The Use of Commercial Fertilizers. The cotton plant responds 

 promptly to fertilization and, except on extremely poor sandy soils or 

 very rich bottom lands, a judicious use of commercial fertilizer is 

 usually profitable. Indeed, on upland soils of average fertility a 

 crop of cotton grown without the aid of fertilizer, received either as 

 a direct application or as a residue from an application to some 

 other crop, will not usually give a profitable return for the time and 

 money expended in its production. 



Previous Treatment of the Land. As with most other crops, 

 the profit resulting from the fertilization of cotton is increased if the 

 soil has previously been brought to a good condition of tilth and con- 

 tains a store of organic matter left by the growth of leguminous or 

 other green manuring plants. 



Phosphoric Acid. Extensive investigations by southern Ex- 

 periment Stations have shown conclusively that phosphoric acid in 

 some form should be used liberally in the production of cotton. It 

 causes a larger increase in yield and it returns a greater profit from 

 the money invested than any other element of plant food. An 



