250 Report of the Department of Botany. 



nineteen. In the experiment of David Dell (the only one in which 

 an unsprayed row was left in a sprayed field) the Station row out- 

 yielded the owner's row by 33.3 bushels per acre, while the unsprayed 

 row yielded 16.7 bushels per acre less than the owner's row. Mr. 

 Dell sprayed eight times. 



Of the sixty-six fields in which these experiments were conducted, 

 only nineteen, or less than one-third, were sprayed by the owner; 

 and of the nineteen sprayed fields certainly not more than nine 

 were properly sprayed. Probably, this represents fairly well the 

 present status of potato spraying at Rush. It is very evident 

 that potato-growers here are still unconvinced that it pays to spray 

 potatoes. If all the summers were like that of 1913 such a view 

 might be justified, but they are not. Another season's experiments 

 may show spraying in a very different light. It is expected that the 

 experiments will be repeated during the coming season. 



