46 HATCH EXPERIMENT STATION. [Jan. 



4. On that plot receiving dissolved bone-black as well as 

 muriate of potash, the crop was in the end a good one. As 

 is well known, the dissolved bone-black contains a large 

 amount of sulphate of lime. It is believed that this may 

 take the place of the lime leached from the soil as a conse- 

 quence of the use of the muriate of potash, or at least that it 

 corrects in some way the faulty condition consequent upon 

 the use of this salt. It may here be pointed out that a 

 similar corrective influence is evident in the results obtained 

 both in 1897 and 1898 upon our other home-test acre, which 

 will immediately be discussed. 



It is of interest, further, to point out that the crop this 

 year upon the lime plot was not quite equal to the average 

 of the nothing plots, while that of the plaster plot (sulphate 

 of lime) was about double that of the lime plot. In the 

 earlier years of this soil test the yield of neither the lime nor 

 the plaster plot ever exceeded that of the nothings, but for 

 the past three years the plaster plot has been relatively gain- 

 ing. The explanation of this difference between the effect 

 of plaster and lime is not apparent. It will be made the sub- 

 ject of future study. 



Conclusions. 



1 . The yield of the plot which for ten years has received 

 only phosphoric acid and potash (41.2 bushels per acre) 

 illustrates in a striking way the comparative independence 

 of the corn crop of supplied nitrogen upon this soil. 



2. The crop raised where nitrogen, phosphoric acid and 

 potash have been yearly applied (nitrate of soda, dissolved 

 bone-black and muriate of potash) for ten years shows that 

 profitable results may be obtained by the use of fertilizers 

 alone. The yearly cost of the application to this plot has 

 been from $10 to $12. The crops have not been much in- 

 ferior to those on the plot to which manure at the rate of 5 

 cords per acre has been yearly applied. The two crops this 

 year are, respectively : for the fertilizer, 55.9 bushels; for 

 the manure, 67.7 bushels. The extra 11 bushels of corn 

 will not cover the added cost of the manure, as compared 

 with the fertilizer ; and in earlier years the differences in 

 yield have been relatively much smaller than this year. 



