140 



EXPERIMENT STATION. 



[Jan. 



A fertilizer of the following composition was used, applied 

 in the indicated amounts per acre : — 



Nitrate of soda, 

 Super^jhosphate of lime, 

 Muriate of potash. 

 Lime, . . . . 



Pounds. 



400 

 1,320 



280 

 1,000 



In order to be certain that the production or reduction of the 

 mosaic disease was due to the excess of fertilizer which was 

 added in each case, a wrowino- medium was taken which con- 

 tained little or no plant food. In this case pure anthracite or 

 hard coal ashes, which had been sifted through a one-fourth- 

 inch sand sieve, were used. 



Five wooden boxes of the same dimensions (45 by 45 by 30 

 centimeters) were tilled to a depth of 25 centimeters with the 

 ashes ; to this was added in each case the requisite amount of 

 the com})lete fertilizer calculated from the above formula. 

 Box 1 contained the complete fertilizer, and nothing else ; to 

 box 2 was added an excess of nitrates equal to that already in 

 the fertilizer ; to box 3 was added an excess of potash equal to 

 that already in the fertilizer ; to box 4 was added an excess of 

 phosphate equal to that already used ; and to box 5 was added 

 an excess of lime equal to that already used, — so that the 

 boxes contained : — 



Table showing Contents of Each Box. 



Here n represents the normal amount of fertilizer. 

 X represents the nitrates. 

 K2O represents the potash. 

 P2O5 represents the phosplioric acid. 

 CaO represents the lime. 



Two tomatoes were planted in each box, one being pruned 

 and the other not. They were allowed to grow for one week, 

 however, before the first pruning, then one plant in each box 



