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The rate of water loss depends on the nature of fruit itself and 

 environmental conditions. The skin prevents free evaporation and is respon- 

 sible for the fact that a free water surface of the same area loses 30 to 

 50 tines as much water. The skin is not absolutely tight. Vifater vapor es- 

 capes through lenticels, called commonly dots, and through the cuticle between 

 the lonticels. About 4 to 10 times as much v/ater is lost through the cuticle 

 as through the lenticels, 



V/hen apples are placed in storage their rate of water loss steadily 

 decreases for some time even if they are placed under constant environmental 

 conditions. This is due to a number of factors, chiefly to the increase of 

 wax or bloom on the surface of the skin, to closing down of lenticels, and 

 to dessication of the skin. 



The grower has some control over natural tendencies, so far as water 

 loss is concerned. Too early or too late picking may make the fruits more 

 susceptible to shrivelling. Washing or brushing for spray residue removal 

 may remove the surface wax and increase greatly the rate of water loss. It 

 is, however, by controlling conditions during the storage period that the 

 most satisfactory prevention of shrivelling can be accomplished. In order 

 to keep v/ater losses down, the temperature in the storage must be low 

 (31°F to 32°F) and relative humidity high (8&% to 90^). 



These two conditions are being achieved by sound engineering devices 

 and good pomological practices. The engineer provides storage with adequate 

 collage to remove field heat from the fruit quickly. He will also try to 

 maintain a minimum differencial between the temperature of the refrigerant 

 and that of the room in order to avoid taking too much moisture from the at* 

 mosphere in the form of frost deposits on the pipes. 



The grower's first effort should be directed toward immediate stor- 

 age of the fruit. The disastrous effects of delayed storage are too well 

 known to need discussion here. There are, however, some other considerations 

 that are not as clearly realized. Among them is the problem of the package, 

 Apple boxes are made of wood v^hich is highly hygroscopic material. Very of- 

 ten they are stored over the summer in hot sheds, packing houses or garrets 

 where they dry up considerably. Y/hen such dry boxes are filled with fruit 

 and taken into the storage, they absorb moisture from the storage atmosphere 

 and from the fruit. 



A dry New England apple box may absorb over half a pound of water 

 in storage, A heavy field box weighing about 12 pounds may absorb nearly 3 

 pounds of water as shown by v/eighing experiments conducted this winter at 

 Rhode Island State College. 



In the same experiment, it was found that during the first 6 weeks 

 of storage, apples in dry boxes lost on the average almost 3 times as much 

 water as apple* stored in wet boxes. It is true, of course, that these boxes 

 were exceptionally heavy, but many farm storages use rather heavy boxes. 



It is clear that the condition of the boxes may influence v;ater loss 

 of apples and thus tho time of shrivelling. It is therefore recommended that 



