No. 6. DEPARTMENT OF AGRICULTURE. S71 



had a relatively higher efficiency than the other phosphate r before 

 the application of the lime in 1898. 



Prof. H. P. Brooks in discussing the results obtained in these ex- 

 periments remarks as follows: "Attention is called to the fact that 

 the crops oo these plots in recent years have not been satisfactory 

 in amount even in the best plots. The fact that no phosphoric acid 

 in any form has been applied during the last nine years sufficiently 

 accounts for this relatively small yield. The results, however, indi- 

 cate a relatively high degree of availability for the phosphoric acid 

 contained in South Carolina rock and in phosphate slag. There can 

 be no doubt that profitable crops of most kinds can be produced by 

 the liberal use of these natural phosphates; and in a long series of 

 years there would be a considerable money-saving in depending, at 

 least in part, upon these rather than upon the higher-priced dissolved 

 phosphates." 



SECOND SERIES OF MASSACHUSETTS STATION. 



In the second set of tests of phosphates the application has been 

 made so as to give each plot the same quantity (1)G lbs. per acre), 

 actual phosphoric acid. The plots so far have had annual applica- 

 tions. In addition to the phosphoric acid, each plot has received, 

 yearly, nitrogen at the rate of 52 lbs. per acre and potash at the rate 

 of l.o2 pounds per acre. This test has been in progress four years 

 and has been cropped as follows: Corn, cabbage, corn and in 1900, 

 two crops harvested, oats, hay and Hungarian grass hay. 



The following are the kinds of phosphates used in this test: 



Plot No. Kinds of Phosi)hate. 



1, No phosphate. 



2, Apatite. 



3, South Carolina rock. 



4, Florida soft phosphate. 



5, Slag phosphate. 



6, Tennessee rock. 



7, No phosphate. 



8, Dissolved bone black. 



9, Raw bone. 



10, Dissolved bone black. 



11, Steamed bone meal. 



12, Dissolved phosphate rock. 



13 No phosphate. 



