No. 6. 



DEPARTMENT OF AGRICULTURE. 



S6y 



the falling off in the yield of the commercial manures and their 

 lack of organic matter would probable be accountable for the in- 

 soluble phosphoric acid of the South Carolina rock falling behind. 

 At least, the experiments reported on previous pages by other sta- 

 tions would indicate this fact. 



EXPERIMENTS BY THE MASSACHUSETTS STATION. 



The Massachusetts Experiment Station has conducted two classes 

 of experiments with ditferent forms and sources of phosphates. In 

 the first test the phosphates were applied on the basis of equal money 

 value and in the second test so as to have the same number of pounds 

 of actual phosphoric acid per acre. 



The first series of experiments were commenced in 1890 on a soil 

 which was well exhausted of available fertility. Previous to 1887 

 the land had been in meadow for a number of years. This meadow 

 was well worn out and yielded but little. From 1887 to 1890 the land 

 was cropped in corn, Hungarian grass, cow peas, vetch and serra- 

 della, receiving no manure or fertilizer of any kind. The soil was a 

 fair sandy loam. The following table gives the quality and analysis 

 of the phosphates used: 



TABLE 22. 



Showing Schedule of Fertilizers Used in the Experiments Conducted by the 



Massachusetts Station. 



« 



B 



3 



a 



(k 



Kind of Phosphate. 



m 



o 



J3 



Pi 



G a 



o 

 o. 



Ph 



0) 





to 

 1 



2 

 3 

 4 



4 



No phosphate 



Slag phosphate •.-. 



Mona Island guano, 



Florida soft phosphate, .., 

 South Carolina phosphate. 

 Dissolved bone black 



19.0 

 21.9 

 21.7 

 27.6 

 15.8 



S96 

 903 

 917 

 546 



•The quantity varied from year to year with the marltet value. 



tThe no-phosphate plot was not used at the beginning of the experiment, but added in 1895. 



