STORAGE OF APPLES IN THE PACIFIC NORTHWEST. 9 
also to preserve the quality and appearance of the fruit in storage. 
Because of its nature, scab is more conspicuous on yellow and green 
varieties than on red ones. There are few, if any, varieties that 
are entirely immune from the disease. As 1s the ease with all fungous 
troubles affecting apples in storage, immediate storage and prompt 
cooling are of some value in reducing the injury, but the main reli- 
ance for its control must necessarily depend on proper spraying.’ 
FACTORS AFFECTING THE DEVELOPMENT OF BITTER-PIT IN STORAGE. 
Occasionally bitter-pit causes serious losses in storage and in the 
Pacific Northwest is frequently confused with fruit-spot and stig- 
monose. The fungous fruit-spot of the East is probably not present 
in the Pacific Northwest. Stigmonose, however, is common in this 
section and is very hard to distinguish from bitter-pit. The presence 
of a minute puncture in the skin over the affected area is sometimes 
the means of identifying stigmonose. The spots of the bitter-pit 
are usually visible on the surface as dark, slightly sunken areas one- 
eighth to one-third of an inch in diameter. 
Many affected fruits are sorted out at packing time, but as they 
are hard to recognize and the pits often develop in storage, the 
trouble is not eliminated thereby. No effective methods of control 
have been.suggested, as up to the present time the cause is not defi- 
nitely known. It does not appear to be due to any organism, but is 
said to be caused by an unbalanced condition existing in the tree or 
parts of the tree that prevents the proper development of the fruit. 
Some varieties, such as Baldwin, Yellow Newtown, and others, ap- 
pear to be particularly susceptible to the disease. It would not seem 
advisable to store apples for first-class trade from orchards where 
a high percentage of the fruit is thus affected. The disease mars the 
attractiveness of the fruit and renders it unfit for other than culinary 
use, but it does not appear seriously to affect its keeping qualities. 
TYPES OF DECAYS DEVELOPING IN STORAGE. 
The decays affecting apples in cold storage may be divided into 
two general classes: (1) Physiological or natural death decay of fruit 
which has reached the end of its life; (2) fungous or bacterial decays 
or those caused by the growth of some organism in the tissue of the 
fruit. These again may be divided into two general classes: (1) 
Parasitic fungi, those that have the power of penetrating the sound 
unbroken skin of the fruit, and (2) saprophytic fungi, those that 
ordinarily do not penetrate the skin unless it is injured, broken, or 
in a weakened condition. 
1The various State experiment stations and the United States Department of Agricul- 
ture give concise directions for effective methods of scab control. Any failure properly 
to control scab under normal conditions is usually because the grower did not spray 
thoroughly or at the proper time. 
4714°—17—Bull. 587 
2 
