GRAPES AXD OTHER SMALL FRUITS 15 



more than a mere russet brought about by any mechanical or chemical 

 agent. 



The spotting is well described by its various names. It is entirely 

 superficial and may occur anywhere on the berry, but is usually found 

 at or near the blossom end. Bunches with more than half a dozen 

 of the spotted berries are rare, and there are vineyards in which the 

 blemish does not seem to occur at all. 



SCARRING 



Several different kinds of marks or spots occur on grapes which are 

 well described by the term "scarring." Among them are the following: 



1. Cane or leaf rubs, that are brown to black and somewhat elongated; they 

 usually have a smooth surface (pi. 10, C). 



2. Spots caused by hail injury when the fruit was young. These are tan- 

 colored, have a roughened surface, and are generally depressed below the unin- 

 jured skin around them. 



3. Thrips injury that occurs as russeted areas, sometimes involving the entire 

 surface of the berry. 



4. Small, circular, smooth, brown spots or flecking in the skin of Sultanina and 

 occasionally of Malaga. The cause of these is unknown. 



The spotting known as black measles is described on page 4. 

 Scarring of any kind detracts from the appearance of the fruit, but, 

 so far as known, none of the types predisposes the fruit to decay. 



SHOT BERRY 



The condition known as shot berry (pi. o, B), seen most often in 

 Sultanina, Malaga, Muscat, and Emperor grapes, is characterized by 

 small, poorly developed berries scattered among the normal-sized 

 berries of the bunch. In varieties that normally produce seeds these 

 small berries are usually seedless. 



The condition is frequently seen in fruit as it comes to the packing 

 house, but does not often appear on the market because affected berries 

 are trimmed out in packing. It is not associated with decay of any 

 kind, either of the stems or of the berries. 



Shot berry is apparently due chiefly to poor pollination, though the 

 causes that bring this about are either not known or are poorly 

 understood. 



Little is known of methods of control. The most definite recom- 

 mendations that can be made are that all vineyard practices should be 

 such as to keep the vines in a vigorous, healthy condition. It is 

 advisable to prevent overbearing. 



SULPHUR DIOXIDE INJURY 



In California, grapes are frequently fumigated with sulphur dioxide 

 to prevent the development of decay. The treatment may be applied 

 to fruit in refrigerator cars, in cold-storage rooms, or in small rooms 

 built at packing houses for the purpose. Three methods are in com- 

 mon use. One of these consists in burning sulphur in shallow pans 

 in the car or other space where the grapes are held. In the other two 

 methods, sulphur dioxide from cylinders of the liquefied gas is either 

 introduced full strength into the car or storage room and there allowed 

 to mix with air, or it is first mixed with air and the mixture is intro- 

 duced into the space containing the fruit. 



