CHAPTER 30 



METHODS OF CONTROL 



From a practical consideration the greenhouse 

 grower is directly concerned in finding control 

 methods to keep the various plant diseases under 

 check. Fortunately, there are numerous methods 

 which if followed out intelligently may be the means 

 of reducing losses to a minimum. These methods 

 may be enumerated as follows : 



1. Soil sterilization. This method has been 

 fully discussed under chapter 3, pp. 32-43. 



2. Seed treatment, taken up in chapter 8, p. 104. 



3. Spraying. 



4. Hygiene. 



3. Spraying 



While the orchardist has learned the necessity of 

 spraying, it is doubtful whether greenhouse growers 

 have sufficiently realized its value. Spraying has 

 two aims : to kill the insect and animal pests, and to 

 control fungous diseases. The substances which are 

 used for the one purpose are without effect on the 

 other. 



Insecticides 



All animal and insect pests are best controlled by 

 the use of poisonous mixtures applied in the form 



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