From New Jersey Agricultural 

 4 Experiment Station. 



Bulletin 172. 



The Use of Fertilizers. A Review of the Results of 

 Experiments with Nitrate of Soda. 



Professor Edward B. Voorhees. 



The Use of Fertilizers. 



Great gains have been made in the past few years in 

 our knowledge of the necessity of using, and in the meth- 

 ods of use of, commercial fertilizers. A point of primary im- 

 portance that has been learned is that their application is nec- 

 essary for the most profitable culrure of many of the crops 

 grown, not only in the East and South, but also in sections 

 of the country where it was formerly believed that the natural 

 fertility of the soil would suffice for many generations. Their 

 use has spread from the States of the East and South to those 

 of the Middle and Northwest and Pacific slope Wisconsin, 

 Colorado, Minnesota and California now use many tons an- 

 nually. The question as to the need of fertilizer settled, the 

 next in importance is how to use the materials containing the 

 essential plant-food elements in such a manner as to contrib- 

 ute to the best growth and development of the plants under 

 the wide variety of conditions that exist, and thus secure the 

 largest financial return from their application. 



While the three constituents Nitrogen, 

 Nitrogen Should phosphoric acid and potash are all essen- 

 Receive Special tja , because a ]j are i iab i e to exhaustion, 

 Attention. Nitrogen is the one that should receive 



more careful attention than the others, first, because it is the 

 most expensive of the three to supply. Nitrogen is more ex- 

 pensive than either phosphoric acid or potash, largely because 

 it costs more to produce it. The great natural deposits of 

 phosphates in America and other countries make the possi- 

 bilities of their exhaustion very remote; besides, the compara- 

 tive ease of mining, combined with the facilities with which 

 these phosphates may be converted into superphosphates, 

 materially reduces the cost of immediately available phos- 



