6 BULLETIN 1448, U. S. DEPARTMENT OE AGRICULTURE 



wormy or otherwise injured fruit is not an indication of picking 

 maturity. 



The development of water core in the fruit is a very important 

 consideration in determining when to pick certain varieties. Recent 

 investigations by Brooks and Fisher 6 have shown that water core 

 usually develops first in fruit exposed to the direct sunshine on the 

 south and west sides of the trees. Consequently, in looking for the 

 appearance of water core in any variety, apples from the exposed 

 south or west and top portions of the tree should be examined. If 

 water core is not found or if it is present in only a slight degree in 

 fruit from these positions on the tree, it is improbable that it will be 

 present to an injurious extent in fruit from more protected portions 

 of the tree. 



Water core in appreciable extent seriously injures the storage 

 quality of varieties which ripen rapidly in storage, such as Jonathan, 

 Delicious, and Winter Banana. With the slower softening, longer 

 keeping varieties, such as Rome Beauty, Winesap, and Yellow New- 

 town, a small amount of water core in fruit at picking time will 

 apparently disappear while the fruit is in storage, without appreci- 

 able injury to the storage quality of the fruit. 



TIME OF PICKING IN RELATION TO VARIETY CHARACTERISTICS 



Because of the wide variations which occur in the same variety 

 when grown under the varying climatic conditions prevailing in 

 different parts of the United States, and because of the great varia- 

 tions in the factors which determine the optimum picking time for 

 different varieties, it is difficult to discuss the relative value of differ- 

 ent tests for apple varieties in general. The storage quality of cer- 

 tain varieties is greatly reduced by leaving the fruit on the tree too 

 long, whereas with other varieties the greatest harm results from 

 picking the fruit too early. Consequently it is believed best to dis- 

 cuss the merit of these different tests for time of picking and the best 

 time for picking different varieties in detail in connection with the 

 various commercial apples. Only those varieties are included which 

 have been studied sufficiently for the writers to feel fairly certain of 

 the dependability of their observations and tests and of the recom- 

 mendations made. 



In the following discussion reference is repeatedly made to the 

 susceptibility of varieties to storage scald in relation to the best pick- 

 ing date. It should be pointed out that in the box-packing districts 

 fruit of these scald-susceptible varieties is nearly always wrapped in 

 oiled paper, which almost entirely controls scald. The use of oiled 

 paper in barrels and baskets is increasing and serves to lessen greatly 

 the probability of fruit scald in these packages. If oiled paper is not 

 used, however, and even when it is used on the more susceptible varie- 

 ties, particularly when they are packed in barrels, the susceptibility 

 of the variety to storage scald is an important consideration in deter- 

 mining when to pick. It is a definitely established fact that well- 

 matured and well-colored fruit of the susceptible varieties will scald 

 much less than will that harvested in a somewhat immature con- 

 dition. 



6 Brooks, C. and Fisher, D. F. water-coee of apples. Jour. Agr. Research 32 : 223- 

 260, illus. 1926. 



