THE CITRUS WHITE FLY: INJURY. 
21 
shipping quality of the fruit directly, but the processes of cleaning 
have been proved to be of considerable importance in this respect. 
The subject of the deterioration in shipping quality of citrus fruits 
has been thoroughly investigated in California by agents of the 
Bureau of Plant Industry under the direction of Mr. G. H. Powell. 1 
Their report shows in a conclusive manner that the amount of decay 
in shipment is very materially increased by brushing or washing the 
fruit to remove the sooty mold. Table II, arranged from data pub- 
lished in the report referred to, shows the effect of dry brushing and 
washing fruit on the percentage of decay. 
Table II.— Effect, on decay, of cleaning sooty mold from fruit. 
Record 
No. 
Unbrushed 
fruit ap- 
parently 
sound. 
Dry 
brushed 
fruit ap- 
parently 
sound. 
Washed 
fruit ap- 
parently 
sound. 
1 
2 
3 
Per cent. 
2.7 
1.9 
Per cent. 
6.6 
4.2 
1.8 
Per cent . 
17.8 
10.0 
2.6 
It will be observed that dry brushing increased the amount of 
decay to about two and one-half times the decay in the unbrushed in 
record No. 1, and to about two and one-fifth times in record No. 2. 
Washing increased the amount of decay to about six and two-thirds 
times in record No. 1, and to about five and one-fifth times in record 
No. 2. 
The injury from cleaning the fruit is due to the increased opportu- 
nities for infection with spores of the blue mold and to mechanical 
injuries in the process of cleaning. The chances of decay are still 
further increased whenever the fruit is not thoroughly dried before 
packing. Washing in constantly running water or by running the 
fruits through brushes with water constantly sprayed- over them is 
considered much less objectionable than the ordinary systems. 
Flavor. — The attack of the white fly is generally supposed to affect 
the quality of the fruit in a marked degree. Dr. Webber and Prof. 
Gossard describe the flavor as insipid as a result of heavy infestations. 
The latter presents the results of chemical analyses of samples of the 
fruit of tangerine trees in two adjoining groves. In one grove the 
white fly was completely controlled by spraying; in the other the fly 
was unchecked. The analyses showed that there was, in the samples 
from the latter grove, 15 per cent less reducing sugar, 15 per cent 
less sugar dextrose, and 5 per cent less citric acid. While oranges 
and tangerines are frequently much affected in flavor, thoroughly 
blackened groves in many cases produce as well flavored fruit as can 
1 Bulletin 123, Bureau of Plant Industry, U. S. Department of Agriculture. 
