BUREAU OF ENTOMOLOGY AND PLANT QUARANTINE 57 
reestablish themselves during the period that elapsed after the last 
early-season application was made and at the time when bollworms 
began to develop. Heavy infestations did occur in a few fields which 
received treatment beyond June 15. 
Cotton Aphids Easily Controlled 
Surveys conducted over most of the Cotton Belt showed that the 
1951 aphid infestation was light. Damage to cotton by various root 
aphids has greatly abated in South Carolina since the use of organic 
insecticides for control of the boll weevil, due chiefly to the control of 
ants attending them. 
Combinations of insecticides to prevent aphid buildup were tested 
in numerous field plots. In Mississippi it was found that the use of 
aldrin, dieldrin, toxaphene, or heptachlor for boll weevil control did 
not cause aphids to increase unless DDT was mixed with it. When 
DDT was included in the spray formulations for bollworm control, 
0.5 percent or more of compound 923, benzene hexachloride, EPX. or 
parathion, prevented an increase in aphids. Also, two new promising 
insecticides for boll weevil control, endrin and isodrin, did not cause 
an increase in the aphid population unless mixed with DDT. Since 
endrin showed promising results against the bollworm, DDT may not 
need to be formulated with this material. 
Cotton Fleahopper Unusually Scarce 
Cotton fleahopper and related insect infestations were usually light 
throughout the 1951 growing season in the 12 cotton-growing States 
included in the survey. The heavy poisoning schedule maintained for 
boll weevil, thrips, bollworms, and other cotton pests apparently 
helped to hold the cotton fleahopper in check in most areas. 
Effective Controls Developed for a Variety of Cotton Insects 
Serious infestations of the garden webworm, yellow-striped army- 
worm, fall armyworm, and other lepidopterous larvae requiring con- 
trol measures, developed over large areas of Texas, Mississippi. Okla- 
homa, and other States. Spider mite infestations were more general 
than usual and serious infestations developed in all cotton-growing 
areas. Although the cotton leaf worm is usually a serious pest in many 
South Central States, no infestations developed to require control 
measures in 1951. Thrips and cutworms caused considerable damage 
to cotton in Texas. Oklahoma. Mississippi, and South Carolina. 
Effective control of the garden webworm was obtained with toxa- 
phene, DDT, parathion, dieldrin, or aldrin; promising new insecti- 
cides tested included endrin. Metacide and Systox. 
EPX was found to be the most effective insecticide tested against 
the yellow-striped armyworm. If applied in the early stages of de- 
velopment, good control was also obtained with toxaphene, DDT, 
dieldrin, TDE. parathion. and with toxaphene plus DDT. 
Good control of the fall armyworm was obtained with toxaphene, 
chlordane. DDT, dieldrin, aldrin, benzene hexachloride, or endrin. 
In Texas TEPP, parathion, and malathon gave a high initial kill of 
spider mites, but the infestation built up again within 5 to 9 days. 
