1920] HORTICULTURE. 39 



Observations on temperature changes in cold storage showed that it requires 

 30 to 60 hours to reduce tlie temperature of fruit in the center of a box or 

 barrel from a temperature round 70° down to 35°, the temperature of apples 

 in boxes being reduced sooner than tliat of apples in barrels. Unwrapped apples 

 packed in boxes were more quickly affected by changes in storage temperatui-es 

 than similar wrapped apples. Small changes in room temperatures do not 

 materially change the temperature of fruit in the package, particularly of 

 wrapped fruit. The author points out the importance of not exposing picked 

 apples to the sun either in the orchard or in the packing shed, as they absorb 

 considerable heat, and when first placed' in cold storage apples which have ab- 

 sorbed heat during the day do not cool oft" readily at night even though the nights 

 are comparatively cool. When the fruit is ready for storage it should be cooled 

 to 32° as quickly as possible. 



Fruit cool storage: Experiments with apples and pears, G. Esam {New 

 Zeal. Jour. Agr., 20 {1920), No. 1, pp. 10-18). — The results are given of experi- 

 ments conducted under the direction of the New Zealand Department of Agri- 

 culture at Hawke's Bay in 1919 to determine the eft'ects of different methods 

 of picking, handling, and packing apples and pears on the cold storage of fruit. 

 In brief the results indicate that a good many faults attributed to cool storage 

 lie in the unsatisfactory condition in which the fruit is often placed in store. 



Effect of temperature on the resistance to wounding of certain small 

 fruits and cherries, L. A. Hawkins and C. E. Sando {U. 8. Dept. Agr. Bui. 

 830 {1920), pp. 6, fig. 1). — Puncturing experiments were conducted with red and 

 black raspberries, blackberries, strawberries, and cherries, with the view of 

 determining the influence of temperature on the resistance of the epidermis of 

 the fruit to wounding. A modified Joly balance, here illustrated and de- 

 scribed, was used in puncturing the fruit. 



The results of these tests show that the average pressure required to punc- 

 ture fruits that have been cooled is considerably more than that required for 

 warm fruit. This was true not only for freshly picked, warm and cooled 

 fruit, but also for fruit that was maintained at ice-box temperature (about 

 16° C.) for 24 hours, tested upon removal from the ice box, and tested again 

 after warming to room temperature. Washing in tap water without lowering 

 the temperature did not apparently increase the resistance of the fruit in 

 puncturing. The test as conducted with red raspberries indicates that certain 

 varieties may be more readily punctured either when fresh or after cold storage 

 than others. 



It is suggested that this increase in the resistance of the skin to mechanical 

 injury is an important factor in the favorable results obtained in the prompt 

 cooling and refrigeration of berries. It would seem also that the picking of 

 berries in the early morning when they are cool, as is quite coumionly prac- 

 ticed in some regions, would be decidedly advantageous since the evidence 

 obtained indicates that berries moist with dew would not be more susceptible 

 to injury than dry fruits. Although no attempt was made to determine the 

 reason for the increase in resistance to puncture due to cooling the authors 

 suggest that the surface' of the fruit might be covered with a wax, which 

 softened at the higher temperature but became hard and more resistant when 

 colder. Another purely mechanical explanation is that the walls of the drupe- 

 lets or of the external cells of the fruits have a lower coefficient of expansion 

 than their contents. If this were the case the walls would be under greater 

 strain at higher temperatures and would thei'efore puncture more easily. 



An index of hardiness in peach buds, E. S. Johnston (Atner. Jour. Bot., 

 6 {1919), No. 9, pp. 373-379, figs. 2).— A contribution from the Maryland Ex- 

 182230°— 20 4 



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