5 1 ANNUAL REPORTS OF DEPARTMENT: or AGRICULTURE, 1 ■" 
:i general in festal loo was eradicated from 56 city block- in Mata- 
moros, or m least reduced to such a low level thai danger of an 
invasion of the Eio Grande Valley of Texas has boon minimised 
Four applications of spray were made cooperatively by tlie Mexican 
National Blackfly Committee and Bureau workers. Spray machine.-, 
drivers, and most of the insecticides needed for tliis wort were pro- 
vided by the national committee. One small additional infestation 
was later found, but is believed to have been eradicated. 
In January L953, 17 properties were found infested with the citrus 
blackfly in Ilcrmosillo, Sonora, Mexico. These infestations are from 
1 to 5 blocks distant from the zones sprayed in 1951 and 1'.>.V_!. None 
of the infestations appeared to have been established more than 8 
months, nor was infestation found in the areas previously infested 
in this town. Bureau personnel met with Mexican oflicials and citrus 
growers of the area to plan a citrus blackfly eradication program. 
Spraying of infested properties and security zones around them was 
completed on May 30. The coverage of the 17 known infested prop- 
erties and security zones required a total of 23,300 gallons of a cube- 
oil formula applied to 2,048 citrus trees and other host plants on 
i^i »7 properties. A quarantine station was set up on the highway south 
of Hermosillo to protect the area against reiniestation. This station 
was manned by three inspectors, one each being furnished by the 
Bureau, the State, and the Citrus Growers' Committee. 
Cooperative quarantine program in northwestern Mexico 
The Bureau furnishes technical assistance to the Mexican Depart- 
ment of Agriculture in a cooperative quarantine program in the 
northwestern area of Mexico to prevent the establishment of the 
citrus blackfly and other injurious insects close to the International 
Border, thus protecting agricultural areas of the western United 
States from infestations of important pests that do not exist there. 
During the year inspections were made of 75 coastwise vessels at 
Ensenada, Baja California; 5.009 passenger and cargo planes at 
Mexican airports along the California border: 3,535 freight and pas- 
senger railway cars in Sonora; and more than 370.000 pieces of Bag- 
gage belonging to more than 229,000 rail, airline, and highway pas- 
Bengers. Inspections resulted in the interception of more than 4.500 
lot- of prohibited plant material, including plants and plant parts 
infested with the citrus blackfly and the Mexican fruit fly. These 
interceptions included host material of the pink bollworm and the 
boll weevil. 
Introduced parasites greatly reduce citrus blackflics throughout 
Mexico 
In general, citrus blackfly infestation in practically all regions of 
Mexico, except t lie northwest, was greatly reduced by parasites during 
the year. In June L952 all chemical control was discontinued in the 
outh of Victoria and Quaymas. 
The four citrus blackfly parasites Introduced from India are now 
well established in Mexico. Prospaltella sm&thi, which started ^\\\ so 
auspiciously 2 years aL r <>. is now relegated f<> a minor position, except 
in a few regions where the climate appear- suitable. 
Atnitus firs/urn! n/ii continued its role as the most important all- 
round blackfly parasite in Mexico. This parasite is now established 
