10 SELECTION OF LAND IN THE GTJLF COAST REGION. 



THE USE OF FERTILIZERS. 



Commercial fertilizers are in universal use throughout this sec- 

 tion. Recently cleared land, some of the valley soils, and a few up- 

 land types of exceptional fertility require no artificial enrichment, 

 but on most types an application of some kind of fertilizer is consid- 

 ered necessary. Nitrogen, phosphorus, and potash are the substances 

 to be supplied. To these lime may be added, but it is not generally 

 used. A complete fertilizer is one containing at least some quantity 

 of each of the first three elements. 



Nitrogen is the most expensive. In the manufactured goods com- 

 monly sold the guaranteed percentage of nitrates is secured by the 

 use of cottonseed meal, nitrate of soda, or some kind of slaughter- 

 house refuse. While enormous quantities of nitrogenous substances 

 are annually purchased by farmers, the requirements of all the staple 

 crops could be largely met by the methods of soil management sug- 

 gested in the discussion of the organic soil components. The increas- 

 ing demand for nitrogenous fertilizers is due in a large measure to 

 the prevailing system of farming. 



Phosphorus, or phosphoric acid, the latter the form in which this 

 element is obtained, is finely ground rock phosphate treated with 

 sulphuric acid to render the phosphorus more soluble. It is prac- 

 tically indispensable in southern agriculture, and most of the brands 

 of fertilizer used on corn and cotton land contain relatively high 

 percentages of this element. 



Nearly all the potash used in the manufactured fertilizers comes 

 from Germany. Muriate of potash, potassium chloride, potassium 

 sulphate, and kainit are forms of this material. It is omitted from 

 many grades of commercial fertilizers. Potash is considered more 

 necessary on light, sandy soils than on heavy ones. 



As a very rough approximation of the outlay per acre each year for 

 ordinary crops, it may be stated that from 200 to 400 pounds of com- 

 mercial fertilizer, costing from $20 to $25 a ton, is used. Of course, 

 many farmers apply much greater quantities and others less. Land 

 devoted to grass and forage crops is not generally fertilized. Light 

 sandy soils usually require higher fertilization than the heavier types. 

 When fertilizer is used more durable results are noted on the latter. 

 On poorly drained or indifferently tilled soils fertilizers are of little 

 benefit. 1 



With few exceptions the maintenance of fertility is a fixed charge 

 that must be met as long as the land is cultivated. With the increas- 



1 The literature relating to commercial fertilizers is voluminous. The results of many 

 experiments on different soils and with various crops are given in the publications of the 

 State experiment stations. A summary of much of this information on cotton, corn, pota- 

 toes, and some miscellaneous crops may be found in Bulletins 62, 64, 65, and 67, respec- 

 tively, of the Bureau of Soils. 



