150 



many growers who, not having tried it, retain their 

 prejudice, and cannot grasp the belief in its efficiency. 

 The numerous experimental trials, and the more 

 extended tests in ordinary farm practice, have, however, 

 firmly established its value, and its general adoption 

 is now merely a matter of time. The cost of the 

 spraying will prevent its use to some extent, as the 

 operation may be regarded as an insurance against 

 loss by disease, and there are those who always prefer 

 to risk loss than lay out a sum to protect themselves, 

 hoping that their good fortune may carry them 

 through without their suffering too severely. Ex- 

 perience, however, shows that in this instance the 

 insurance is a wise precaution. 



Spraying does not secure perfect immunity from 

 disease, but if commenced in good time it enables the 

 plant to withstand attack so that, even in years when 

 disease is exceptionally rife, it is little checked by 

 it. If spraying is done carefully, so that all parts of 

 the haulm and leaves are covered with a film of the 

 solution, the fungus will not attack them, but as new 

 foliage is formed, or the spray is washed off, re-spraying 

 may be necessary. The attack on the tubers by the 

 spores washed on to them, is not affected by the 

 spraying. The attack through the hybernating 

 mycelium in the seed cannot be prevented, but it is 

 probably lessened in its severity. 



Experiments with Bouillie Bordelaise. 



A large number of carefully conducted experiments 



