22 BULLETIN 1415, U. S. DEPARTMENT OF AGRICULTURE 
roved through the use of cold storage instead of common storage. 
hee, shippers realize the inporriee of cold storage and are making 
efforts to provide such facilities for handling their apples. The 
buying trade also has learned to favor the purchase of such fruit. 
It has been estimated that in the Northwest, 75 to 85 per cent of the 
pack of standard varieties is bought by the trade with a view to cold 
storage in the Kast. The quantity, location, and season of these 
stocks are described under ‘‘ Cold Storage Holdings.” 
COMMON STORAGE 
There are many types of common storage, some of which are 
nothing more than sheds or basements of houses and store buildings. 
Such places are not suited for keeping apples in good condition. 
But a type of insulated common storage is used east of the Cascade 
Mountain Range in the Pacific Northwest apple sections which has 
Fic. 12.—Good type of packing and common storage house 
proven fairly successful for handling late storage varieties such as 
Winesap and Yellow Newton. To cool the fruit, openings are pro- 
vided near the ground or lower part of the building for entrance of 
cold air. This air is released directly beneath a slatted floor on 
which the boxes of apples are stacked. Shafts leading upward 
through the ceiling and roof remove the warm air given off by the 
fruit in cooling. The circulation of air in this type of storage is 
obtained through natural ventilation induced by the difference in 
weight of air at different temperatures. Motor-driven fans are 
sometimes used to assist the natural ventilation. Figure 12 shows 
a good type of common storage and packing house in the Pacific 
Northwest. 
COLD STORAGE 
The ideal range of temperature for storage of most varieties of 
apples is about 30 to 32° F., and without the provision of mechanical 
refrigeration it is impossible to maintain such temperatures through- 
