JOURNAL OF AGRICULTURAL RESEARCH 
Vol. XXVI. Washington, D. C., Dec. 15, 1923 No. it 
OILED WRAPPERS, OILS AND WAXES IN THE CONTROL 
OF APPLE SCALD 1 
By Charles Brooks, J. S. Cooley, and D. F. Fisher, Pathologists, Office of Fruit 
Disease Investigations , Bureau of Plant Industry, United States Department of 
Agriculture . _ _ 
* INTRODUCTION 
It has been pointed out in earlier publications 2 that apple scald could 
be partly or entirely controlled by the application of various oils, fats, and 
waxes, either to the apple wrappers or to the apples themselves. The 
present paper reports the results of more complete and detailed studies 
on the relation of oils and waxes to the behavior of apples in storage. 
STORAGE EXPERIMENTS WITH WRAPPERS 
The results of five years’ experiments with various kinds of wrappers 
are reported in Table I. It will be noted that the tests were made in 
various sections of the country and on varieties that are particularly sus¬ 
ceptible to scald. The northwestern apples were mostly from the fancy 
grade and the eastern ones from the early pickings and greener lots. 
The eastern apples were packed in barrels and the northwestern ones in 
boxes and all were held in the local commercial storage plants, usually at a 
temperature of 32 0 . Unless otherwise stated they were wrapped on the 
date of picking and placed immediately in cold storage. 
The scald values given show the general severity of the disease, allow¬ 
ance being made for the surface area scalded and the intensity of the scald, 
as well as the number of apples affected. Scald was not usually evident 
when the apples were removed from storage, but developed rapidly as 
the fruit became warm. The percentages of scald reported for eastern 
apples are based upon the condition of the fruit after being held for 3 days 
at 70° F., and those for northwestern apples on the condition of the fruit 
after 7 to 10 days at 55 0 to 6o° F. In most cases the apples were held 
for later notes, the contrast between the fruit in the oiled wrappers and 
that in untreated wrappers becoming greater with the extension of the 
after storage period. 
Table I. —The effect of oil, paraffin, and other wrappers upon the development of scald 
Variety, locality of orchard, date of 
picking, and kind of wrapper. 
| —v. 
j Febru¬ 
ary. 
| March. 
1 
| April. 
1_ 
May. 
j June. 
EASTERN APPLES. 
Grimes Golden, Vienna, Va., Sept. 18, 
1918. 
(20) 
38 
27 
18 
23 
15 
0 
D. F. appi 
j ; 
i 
1 
Unwrapped. 
.j 
Unoiled wrapper.j 
Paraffin wrapper No. 1. 1 
Paraffin wrapper No. 2.j 
Paraffin wrapper No. 3.j 
Mineral oil wranner No. ia.. 1 
.i 
1 Accepted for publication Oct. 22, 1923. 
3 Brooks, Charles, Cooley, J. S., and Fisher, 
,E SCALD. 
In Jour. Agr. R< 
esearch,' 
y. 16, p. 
195-217,11 fig. 1919. 
2 fig. 1919. Literature cited, p. 240. 
nature and controt op apple scald. In Jour. Agr. Research, v. 18, p. 211-240, 
Journal of Agricultural Research, 
Washington, D. C. 
■S^) 
Vol. XXVI,’ No. n 
Dec. 15, 1923 
Key No. G-344 
71688—24-1 
