16 



It will probably be first apparent on the shoots of the vine, on 

 which the spots extend lengthwise, giving them a speckled ap- 

 pearance when abundant. 



It also attacks the leaves and especially the veins and stalks. 

 The stalks of the clusters are often affected too, and when com- 

 pletely girded, all the berries below the disease-ring remain green, 

 and shrivel up. 



Treatment — When it is known that a vinery is liable to be 

 attacked by this and other fungus diseases, spraying with Bordeaux 

 mixture should be commenced as soon as the first leaves have 

 fully expanded. The second application may be made after 

 flowering, and the third from 2 to 4 weeks later, according to 

 whether the weather is favourable to the disease. The Bordeaux 

 mixture may safety be used until the berries are three-fourths their 

 full size. After that the application may leave a stain which 

 would reduce their market value, and it is better to use the ammo- 

 niacal carbonate of copper about every 10 days even after the fruit 

 is fully formed, if the disease is rampant. 



The clusters should be sprayed as well as the leaves, especially 

 when they are young. The reason for several applications is that 

 the spores of the fungus resist successfully every destructive agency 

 and it is only when they have already germinated that they can 

 be killed. Everything depends upon the thoroughness of the 

 spraying, and each vine should receive about one quart of liquid 

 at each application. 



Besides the use of the Bordeaux mixture, it is customary to treat 

 the vines in the winter months when they are bare of leaves and 

 dormant, with the sulphuric acid and sulphate of iron solution, 

 applied by means of a brush or a swab made of rags tied around 

 the end of a stick. The effect on the wood is to blacken it which 

 is looked upon as a test of the thoroughness of the work, and 

 whenever the colour remains after 2 or 3 days, a second applica- 

 tion should be made. 



BLACK ROT. 

 (Loestadia, Bidwellii, V. & R. ; Phoma uvicola, B. & C.) 



The Black Rot is even more destructive than the "anthracnose" 

 and besides causing the rotting of the fruit, attacks the leaves and 

 shoots. 



Description — It is readily distinguished from anthracnose by the 

 centre of the dark disease spots having a number of minute pimples, 

 from which the spores come, and are carried by the lightest breeze 

 to other berries and to other parts of the vine. 



It does not attack the stalks of the clusters, as in anthracnose; 

 and on the leaves it is found originating between the veins, not on 

 them, and has minute pimples in a band near the edge of the 

 affected part. 



Grapes are nearly or quite full grown when the disease appears. 

 The spots are first purplish-brown, the whole berry then becomes 

 affected and gradually turns black and the pimples make their 

 appearance. The grape at the same time shrivels, but does not 



