BUREAU OF ENTOMOLOGY AND PLANT QUARANTINE 25 
Several of the new insecticides appear promising in the control of 
the corn root worm on peanuts. In preliminary tests, aldrin, at the 
rate of 4 pounds an acre, when mixed with a commercial fertilizer and 
applied to soil in which peanuts were being grown, gave a 100-percent 
control of the root worm. Neither benzene hexachloride nor lindane 
can be recommended for the control of the corn rootworm on peanuts 
because both impart an off-flavor to the harvested peanuts. 
Rhodes-Grass Scale Hard Hit by Freeze and Drought 
The Rhodes-grass scale has been recorded from 106 counties and 
parishes in the United States, including 55 in Texas, 25 in Louisiana, 
3 in Mississippi, 1 in Alabama, and 22 in Florida. It has been found 
infesting 60 host plants. In southern Texas, however, where the 
scale has been of economic importance as a pest of Rhodes-grass, the 
unusually cold winter of 1950-51 and an extended drought reduced 
the number of insects to a very low, noneconomic level. 
The range grasses Angleton bluestem, Brahman grass, and K-R 
bluestem are apparently resistant to the Rhodes-grass scale. One of 
the systemic insecticides may be practical for use in controlling the 
scale on lawns and golf courses. 
The studies were conducted with funds authorized under the Re- 
search and Marketing Act. 
European Corn Borer Spreads Into Seven More States 
Further spread of the European corn borer was recorded in 1950, 
when the pest was found for the first time in Alabama. Arkansas, 
Colorado, Georgia, Mississippi, Oklahoma, and South Carolina. In 
addition, nine States previously infested reported dispersion of the 
borer within their boundaries. The number of counties known to 
be infested was increased by 5 in Illinois, 15 in Kansas, 6 in Kentucky, 
I in Minnesota, 5 in Xebraska, 3 in North Dakota, 1 in South Dakota, 
32 in Tennessee, and 6 in Virginia. 
Heavy flights of moths and extensive egg laying in June and July 
pointed to a damaging infestation of borers in the Corn Belt in 1950. 
However, the weather was very unfavorable to the borer. Develop- 
ment of first-generation larvae was retarded, their survival was low, 
and an unusually small percentage of them pupated. Second-gen- 
eration moth flight and egg laying were much less than expected. 
Annual fall surveys by State agencies, in cooperation with the Bu- 
reau, showed that borer numbers in 1950 were materially lower than in 
1949 over much of the infested area. Corn borer numbers in the 
Eastern States remained at the low level of 1919. In the North 
Central States the borer showed a general decline in numbers from 
1949. 
Damage by the corn borer in 1950 was estimated at 58,765,000 
bushels of field corn, valued at $84,912,000. The bushel loss was about 
81 percent less in 1950 than in 1949. 
The Bureau continued to assist State agencies in providing infor- 
mation for growers and other interested groups on the need for and 
proper use of insecticides to control the corn borer. In 1950 the pro- 
gram was expanded to include 14 States. 
