Nov. 15. 1919 Nature and Control of Apple-Scald 239 



fruit in good condition but serving also as a continual source of mis- 

 understanding. 



The actaul losses caused by scald and the uncertainty it introduces 

 into the apple trade add greatly to the cost of market operation and help 

 to widen the gap between the producer's and the consumer's prices. 

 The foregoing experiments show that it is a preventable disease and that 

 with proper methods of handling the apples in the orchard and in trans- 

 portation and storage the disease can be reduced to a negligible quantity 

 if not entirely eliminated. 



SUMMARY 



(i) The foregoing experiments show that the occurrence of apple- 

 scald is determined by orchard, packing house, transportation, and 

 storage conditions. 



(2) As has been shown by other investigators, mature fruit has in general 

 scalded less than immature; but it has also been found that the fruit 

 surfaces just changing from green to yellow have scalded worse than 

 those that were a leaf green and worse than those that had more com- 

 pletely changed to yellow. Well-colored red fruit surfaces have been 

 practically immune to scald. 



(3) Apples from trees receiving heavy irrigation have scalded worse 

 than those from trees receiving light irrigation. This was found not to 

 be due to the greater number of large apples in the former case but to 

 some forcing efifect that increased the susceptibility to scald in both large 

 and small apples. 



(4) Delayed storage haS increased or decreased apple-scald, depending 

 upon the amount of aeration the apples received during delay. 



(5) Apples in ventilated barrels have developed less than one-third as 

 much scald as those in commercial barrels when both were held in a 

 storage room that received an occasional ventilation, but where the 

 storage room received little or no ventilation the ventilated barrels 

 c^-used but little decrease in scald. 



(6) The amount of scald developed in cold-storage plants has varied 

 greatly with the location in the room. Apples near the aisle or near a 

 door have scalded far less than those in the bottom of the stack. Boxed 

 apples exposed to a continuous air current of 0.88 mile per hour in a 

 commercial storage plant have been practically free from scald, while 

 similar apples that did not receive the constant fanning became badly 

 scalded. Stirring of the storage air has been found more important than 

 its renewal in the prevention of apple-scald. 



(7) The ordinary commercial apple wrappers have caused but little 

 decrease in scald, and paraffin wrappers have been but slightly better, 

 but wrappers impregnated with various fats and oils have either entirely 

 prevented the disease or reduced it to a negligible quantity. In barrel 



