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DISEASES. 



We have been very desirous of stating our opinions 

 generally upon vegetable diseases, but until now 

 have never had a few pages to devote to the subject. 

 The desire arose from the conviction that a knowledge 

 of principles applicable to plants generally affords 

 light and guidance, without possessing which the 

 gardener must be a mere empiric. In none is he 

 usually more so than as regards the diseases to which 

 his crops are liable. Numerous as are these, and 

 destructive as they are to his interests, yet no subject 

 connected with his art has obtained so little attention, 

 and never was even trivial attention followed by bene- 

 fit less important. The reason of the deficiency of 

 benefit is not difficult to explain. 



Common experience teaches us that diligence and 

 perseverance, directed by judgment, are the essential 

 preliminaries to success. In examining — in searching 

 for the causes of the diseases and decay of vegeta- 

 bles — we have fewer guides, less assistance from the 

 individuals affected, than we have from a diseased 

 animal; fewer symptoms marking the commencement, 

 or seat of the evil ; yet where is the cultivator who 

 ever took a fraction of the care exercised or a decimal 

 of the attention to discover the cause, the progress, 

 or the cure of one disease that sometimes brings ruin 



