442 Bulletin 76. 



C. Anthracnose. 

 {Sphaceloma ampelinum.') 



Upon certain varieties, as Moore's Diamond, Brighton and oth- y 

 ers, anthracnose is sometimes very severe. It attacks the green J 

 stems, leaves and fruit, and sometimes causes a total loss of ' 

 crop. 



The first indication of the disease upon the stems is the appe . 

 ance of small dark brown or black spots, sunken in the cent 

 portions. These spots enlarge, generally extending up anddoA^n 

 the stem, thus forming oval-shaped areas. Sometimes, however, 

 the disease encircles the stem in such a manner as to girdle it and 

 the result is similar to that which would occur if the girdling had 

 been due to some other cause. This form of the disease is parti- 

 cularly prevalent upon the stem of the grape cluster. Here it is 

 sometimes called "ring-around." As the disease progresses, the 

 central portion of affected areas becomes more sunken and finally 

 assumes an ashen color, only the edges of the afiected part retain- 

 ing the dark color- 



On the fruit, the first stages are similar to those in the stem. 

 The affected part is, however, often surrounded by a band having 

 a reddish tinge and the center does not always assume the same 

 ashen color, but it remains rather a dark brown. The diseased 

 surface is quite smooth, and sometimes measures a quarter of an 

 inch in diameter. If the berry is attacked while young, or if at- 

 tacked in several places when grown, it is of no commercial value. 



Anthracnose of the grape is the most obstinate disease which 

 the New York vineyardists have to combat. No authenticated 

 cases are on record showing that the disease has been successfully 

 treated by the use of the Bordeaux mixture or of any other fun- 

 gicide after the foliage has expanded. In fact, I do not know of a 

 single case in which the disease has been kept under control 

 in this state, whatever the method followed. 



The anthracnose of the grape is probably of European origin. 

 It was introduced into this country fifteen years ago or more, and 

 has since spread into most sections in which grapes are grown. 

 In Europe it has long been successfully treated, but whether 

 the same remedies will answer equally well in this country still 



