HORTICULTUEAL SOCIETY. 285 



localities long enough to aflford them sustenance; but we had 

 hoped that our climatic conditions were such as would give us 

 immunity from disease. 



Our attention is now being called to the fact that a number of 

 diseases of the fruit and vine have made their appearance in dif- 

 ferent sections of the state, and it is in view of this fact that our 

 Society has created a standing committee on grape diseases. I 

 am not enough of a scientist to enlighten you very much on the 

 subject and my opportunities for study and observation have 

 been limited on account of the pressure of other duties, therefore 

 I will confine myself chiefly to what I have observed at home. 



The spring of 1888 was unusually backward; growth com- 

 menced late as well as the season of blooming. The setting of 

 fruit was about three weeks later than in 1887. Again the sea- 

 son was characterized, especially in this locallity, by heavy and 

 continuous rains, while the spring of 1887 was noted for lack of 

 rain fall and the absence of moisture in the form of dew, and 

 entire freedom from disease. 



The first appearance of disease, I noticed in some of the vine- 

 yards about Lake Minnetonka, at the time of our summer meet- 

 ing. Some of the leaves of Concord showed on the upper surface 

 wrinkled spots and a slight change of color and were somewhat 

 curled. At first I thought it might be the work of aphides, but 

 upon examination I detected slight traces of grape mildew {Per- 

 nospora viticulo); experts say this is always found on the under 

 surface of the leaves commencing in spots of brownish color 

 which adhere closely to the leaf ribs and when the conditions are 

 favorable spreads rapidly and destroys the vitality of the parts 

 affected, causing upon the upper side the appearance of sun- 

 scald. 



Later I discovered it upon leaves of the wild grapes which are 

 growing abundantly in this vicinity. Some of the cultivated 

 varieties in my own vineyard showed a grayish mildew that not 

 only was of a white velvety appearance in patches on the under 

 side of the leaf, but frequently covered the upper side and the 

 leaf stalk, extending to the fruit stems and the younger growth 

 of the cane. In many instances it was so luxurious on wild 

 grapes as to defoliate them and stop further development of the 

 fruit. This was at about the period of coloring of the fruit; the 

 leaves upon some vines of the Delaware and ^gawam com- 

 menced droi)ping before the fruit was fully grown, and in such 

 instances if the fruit did not drop it was worthless, the berries 

 either scalded in the sun or failed to ripen. 



