118 



Eeport of the Chemist 



(6) During the two years the crops on the unfertilized soil 

 used 81.9 pounds of potash, and we will call this the amount 

 available at the beginning of the two years. Adding this amount 

 to the applied amounts, and indicating how much was removed 

 and left each year, we can prepare the following tabulated state- 

 ment: 



When we applied 1,000 pounds of fertilizer, we had in the soil 

 about three times as much potash as the first crop used. At the 

 beginning of the second year, there was more than twice as much 

 as the second crop actually used, and at the end of two years 

 enough still remained unused to meet the demands of another 

 good crop. When we applied 2,000 pounds of fertilizer an acre, 

 there was present for the use of the crop about four-and-one-half 

 times as much as was used by the crop the first season. There 

 was left for the second crop about four times as much as it used; 

 and after the removal of the second crop there remained about 

 three times as much as would be required to meet the demands 

 of another crop. We notice that the excessive application of 

 potash was not so great as that of phosphoric acid, but still, in 

 the application of 2,000 pounds of an average potato fertilizer, 

 there is apt to be applied very much more potash than the single 

 crop can possibly use. 



When we consider that some farmers on Long Island are in the 

 habit of applying a ton of commercial fertilizer per acre every 

 year in growing potatoes and frequently on the same field for 

 some years succession, we see that one of two results must inevi- 

 tably follow: First, there will be an accumulation of plant-food, 

 rendering further fertilization unnecesasry for a period; or, sec- 

 ond, the unused portions of plant-food will be more or less largely 

 lost by leaching. From the general experience gathered it would 

 appear that the latter result most often occurs. 



