Grape. 295 



areas, which renders it more difficult to distinguish this disease 

 from some others. But one peculiarity of anthracnose is that 

 it generally attacks the veins of the leaves, as well as the leaf- 

 stems, and so its identification is not always difficult. The 

 stems of the clusters are also injured, and it frequently occurs 

 that a part is completely girdled, causing a " ring-around," as it 

 is commonly called. The berries below the ring do not ripen, 

 but remain green, and gradually shrivel. 



The berries of some varieties of grapes are almost invariably 

 affected to such an extent as to render them unfit for market. 

 The Yergennes, Diamond, Salem, Agawam, and many others 

 are very susceptible to its attacks. The first indication of the 

 presence of the fungus on the berries is the formation of dis- 

 tinct brown spots which are practically circular in outline 

 (Fig. 58). The discolored part is sunken, and may be bor- 

 dered by a margin which has a tinge of red or purple. If a 

 berry is attacked in several places, it becomes speckled in 

 appearance, until the spots grow into each other, forming con- 

 siderable areas of irregular outline. The portions first diseased 

 may change to a lighter, or even to a gray color, on account of 

 the rupturing of the epidermis or outer skin, forming a hard- 

 ened "scab." 



Treatment. In Europe, where the fungus has long been 

 known, it is the custom to wash the vines and the stakes during 

 winter or early spring with the sulphuric acid and sulphate of 

 iron solution. The liquid is applied by means of swabs or 

 brushes. It blackens the canes, and this is a test of the 

 thoroughness of the work. See pages 45, 152. 



If, after two or three days, there remain portions which are 

 unchanged in color, the vineyard is treated a second time, par- 

 ticular attention being paid to the parts omitted at the first 

 treatment. In addition to these winter treatments, the vines 

 are sprayed during the summer months with the Bordeaux 

 mixture. As these applications are made more particularly for 

 other diseases, the downy mildew and the black rot, they will 

 not be mentioned here in detail. 



European vineyardists seem to have perfect control of anthrac- 

 nose by following the above line of treatments, and the work 

 done in America is also promising. The cost of washing vines 

 and stakes in this country scarcely exceeds two dollars per acre, 



