52 



EXPERIMENT STATION. 



[Jan. 



It will be noticed that the yield on all the nothing plots 

 is extremely small, — considerably less than one-half ton 

 per acre. It will be noticed, further, that neither lime nor 

 plaster used by itself produced an increase ; indeed, the yield 

 on both is lower than the average yield of the nothing plots. 

 Nitrate of soda by itself produces a very small increase; in 

 combination with either of the other fertilizer elements the 

 increase is much larger, but it is best, as would naturally be 

 expected, in combination with both the other fertilizer ele- 

 nients. It will be noted that the use in combination of dis- 

 solved bone black and muriate of potash gives a considera- 

 ble increase in the crop. This increase shows itself almost 

 as plainly in the rowen as in the first crop, as a consequence, 

 of course, of the relatively large proportion of clover which 

 follows continuous use of materials supplying phosphoric 

 acid and potash without nitrogen. The average results ob- 

 tained in the six years during which this field has been in 

 hay will be of interest. They are shown in the following 

 table : — 



Average Increases in Six Hay and Roioen Crops. 



Average Iticreases in Six Hay and Rowen Crops — Concluded. 



This table affords conclusive evidence that hay can be 

 grown at a profit on fertilizers alone, although naturally the 

 increases produced by the very moderate applications of fer- 

 tilizers used in this experiment are not equal to those pro- 



