BUREAU OF ENTOMOLOGY AND PLANT QUARANTINE 53 
of deodorized kerosene with an emulsifying agent, or 0.25 percent of 
toluene plus 1.25 or 1 percent of deodorized kerosene also with an 
emulsifying agent. Taste tests by the University of Maryland on 
canned and frozen asparagus that had been washed in four of the more 
promising formulations showed that each had caused a significant 
off-flavor. 
FRUIT AND NUT INSECTS 
Citrus Blackfly Eradication in Mexico 
Cooperative citrus blackfly survey and control work continue in 
Mexico 
There was additional spread of the citrus blackfly throughout the 
Eepublic of Mexico during 1952. At the end of 1952 this insect had 
reached every citrus fruit growing area in the Republic. In most 
areas the fly has become well established. Elsewhere incipient infes- 
tations exist, which have been prevented from developing by 
aggressive spray campaigns, particularly in the area close to the 
International Border. 
Accidentally introduced into Mexico about 1935, the citrus black- 
fly has spread rapidly from its point of introduction on the west 
coast of Mexico. Its damaging effects can be seen throughout the 
country wherever citrus is grown commercially. Survey work in 
Mexico is conducted to detect infestations that may develop along 
the International Border. Where such infestations are discovered, 
control work is undertaken to prevent them from building up to a 
point where they would endanger American citrus-fruit production. 
This work is done in cooperation with the Mexican Department of 
Agriculture and the local agricultural committees. 
Citrus blackfly infestations are difficult to find when populations 
are low. Trees must be inspected almost leaf by leaf. It frequently 
requires 30 minutes or more to thoroughly examine a normal-sized 
citrus tree. During the past year Mexican Nationals, working under 
the direction of Bureau supervisory employees, inspected more than 
34,000 properties for blackflies. Many of these were dooryard plant- 
ings. Trees inspected exceeded 217,000 and 242 blackfly infestations 
were discovered, all of them potentially dangerous to American citrus 
production. These were immediately sprayed by Mexican author- 
ities. The Mexican National Blackfly Committee, in addition to its 
spray campaign, is actively engaged in establishing parasites wherever 
the blackfly has become so widespread as to make its eradication 
improbable. 
Surveys were made in the Lower Rio Grande Valley of Texas dur- 
ing 1952. Inspections were made in all towns and along the principal 
highways in the citrus growing area of the Valley. Trees on more 
than 5,000 properties were closely examined without finding any 
blackfly infestation. 
Large-scale citrus blackfly eradication campaign in northern Mexico 
The eradication of an infestation found in Matamoros, just across 
the river from Brownsville, Tex., and not far from the large Texas 
citrus plantings in the Lower Rio Grande Valley, became the most 
urgent citrus blackfly problem in 1953. Late in 1952 and early in 
