18 ANNUAL REPORTS OF DEPARTMENT OF AGRICULTURE, 1952 
occur only in a limited area in and near Chico and Davis, Calif. The 
control work i- cooperative with the California Department of Ag- 
riculture. Although an extensive survey was made during the year, 
additional live scales were found only in areas near previously in- 
fested plantings. Infestations involving 1,600 additional trees were 
discovered in these nearby areas. 
Approximately t,000 trees were fumigated, 1.2s<) for the third and 
lasi tunc unless scales are found on them later. Because of unfavor- 
able weather condition-, about '2. 000 tree- remain to be treated. 
Owing to a reduction of >taff, the HK>[-:>-2 fumigation program was 
resumed in October with only a single crew. More than 2,200 trees 
had been treated by the end of 1951. 
Inspectors making a routine inspection of host plantings along the 
border of the old University of California campus at Davis, found 
three infested hosts on two adjoining properties, about 1,000 feet 
from the site of the infestation that was eradicated several years ago. 
These infested trees and other hosts in that locality were sprayed 
with the usual 2-percent soluble oil solution. Future operations con- 
template resumption of fumigation activities in this immediate area. 
TRUCK-CROP AND GARDEN INSECTS 
Insect Contamination Problems of Caimers Studied 
Studies are being carried on under Research and Marketing Act 
funds to determine what problems of insect contamination exisl in 
plants processing vegetables and small fruits, and to devise the steps 
that may be taken for solving them. The problems which appear to be 
of concern to canners include: Aphids, corn earworm. a bud maggot, 
and certain caterpillars on leafy vegetables: aphids and certain cater- 
pillars on broccoli and Brussels sprouts; aphids on celery: vinegar 
gnats, thrips, mites, and the tomato fruit worm on tomatoes; asparagus 
beetle eggs and thrips on asparagus; and thrips and mites on berries. 
Twenty-eighl .aiming and processing plants were questioned in Okla- 
homa, Arkansas, Texas, ( Jalifornia, and Utah in L951. None of these 
had iii use satisfactory methods for removing insects from crops 
to be processed. Most processors stated thai whenaninseel infestation 
sriOUS enough to indicate that the pack would be contaminated 
with insects or insect fragments it i< their practice to reject the crop 
fur packing purposes. 
In research under way at Beltsville, Md.. encouraging results are 
being obtained in the development of washes for removing asparagus 
beetle eggs from asparagus being processed. Promising results are 
also being obtained with several dips or washes for removing aphids 
from broccoli. Limited progress has been made (Hi studies of dips to 
remove the larvae of European corn borer from ears of sweet corn. 
The objective of these studies is to develop practical methods whereby 
the processor, through a minor modification of his USUal washing 
process, can free the particular product being processed from insect 
contamination. The availability and adoption of such methods will 
have t he added advantage of benefiting the grower since it will permit 
the acceptance of infested prod nee winch otherwise would be rejected. 
