160 MASS. EXPERIMENT STATION BULLETIN 162. 



has not been the case. The benefits following liming are with all crops 

 greater without dissolved bone black than under otherwise similar treat- 

 ment with it. In other words, the use of dissolved bone black appears to 

 have decreased the necessity for hme. 



Need of Lime as indicated by Relative Crop Increase after Liming. 



' Compared on the basis of relative decrease. 

 2 Relative decrease where lime was applied. 



It must be remembered in studying this table that the increases (or 

 decreases) compared are, first, those under the treatments indicated by 

 the headings of the first and second coluirms of figures; and second, those 

 indicated by the headings of the third and fourth columns. The figures 

 do not indicate the relations between these two pairs of plots (plots 5 

 and 9 and plots 8 and 10). It will be noticed that with one exception 

 these results are perfectly concordant. The use of hme produces, with 

 this one exception, a larger increase (or a smaller decrease) when used 

 without dissolved bone black than when used with it. The exception is 

 the effect upon the stover of the corn crop on nitrate of soda and muriate 

 of potash. No explanation can at this time be offered; but it is made 

 quite apparent by the smaller relative increases (and the larger relative 

 decrease in one case) produced by lime without bone black when the 

 latter is added to nitrate of soda and muriate of potash than when it is 

 added to muriate of potash alone that the soda of the nitrate decreases 

 the necessity for hme, — a fact which is generally understood. 



It would seem to be thoroughly established by the results of these ex- 

 periments that the use of an acid phosphate (dissolved bone black) at 

 least has not increased the necessity for hme. On the contrary, it seems 

 clear that the bone black has reduced this necessity. 



Sulfur supplied. 

 It is recognized that considerable quantities of sulfur, in the form of 

 calcium sulfate, have been apphed to the plots receiving dissolved phos- 

 phates, and that the plots with which these have been compared have 



