DISEASES AND INSECTS. 385 



Sun Scald. This makes its appearance on 

 the leaves in spots of greater or less size, and 

 destroys the tissue. It is of a brick-red color, 

 and this may have given rise to the absurd 

 brick-yard theory by which it was attempted to 

 account for it. Its cause is not certainly known, 

 but it is no doubt of atmospheric origin. It is 

 supposed, with some reason, that globules of 

 moisture are formed into lenses, and the sun, 

 acting upon these, burns the leaves. It does 

 not often affect the general health of the vine 

 seriously. We know of no remedy. 



These are the principal diseases of the vine, 

 in regard to which it may be said, that they are 

 mostly of such a nature that remedies, to be 

 effective, must be used as preventives rather than 

 cures. 



INSECTS. 



It would be somewhat difficult to say whether 

 the vine suffers most from insects or disease, but 

 we think insects might easily be managed by 

 concerted action. In every fruit-growing dis- 

 trict there should be an " Insect Society," which 

 should have a grand spring and fall exhibition, 

 with smaller weekly ones ad interim. At these 

 exhibitions prizes should be offered for the " big- 



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