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important to profitable control as the level of infestation. We have had reports 

 that 10 to 20 percent of the plants in a few fields are covered with aphids. If 

 you attempt control in infestations of this size, leave an untreated section in 

 the field for comparison. 



In severe infestations to corn, apply 1 pound of malathion per acre. 

 One-fourth pound of parathion or phosdrin may he applied, hut only hy operators 

 experienced in handling and applying them. One day should elapse between applica- 

 tions of phosdrin and harvest, 7 days with malathion, and 15 days with parathion. 

 These materials can be applied to sorghums in the early boot stage for aphid con- 

 trol. Allow three days to elapse "between application of phosdrin and harvest, 7 

 days with malathion, and 21 days with parathion. 



Fall armyworm . These brown worms with stripes are attacking some late- 

 maturing fields of corn. Their feeding gives the plant a chewed-up appearance. 

 Fields that are most likely to have a problem are those not yet. in the dry silk 

 stage. Observe the silks and whorls carefully for signs of these insects. If 20$ 

 or more of the plants have young worms and/or egg masses, apply ground sprays con- 

 taining 1 l/2 pounds of DDT or toxaphene per acre. For best results direct the 

 spray at the ear zone or into the whorl. Five percent DDT granules, 15 pounds per 

 acre from ground equipment or 20 pounds per acre by airplane, are also effective 

 on corn that is still in the whorl stage. Once the worms enter the ear, it is too 

 late for effective control. Do not apply DDT or toxaphene to corn used for ensilage 

 or stover. 



Grasshoppers . These insects are now damaging soybeans and corn. The 

 hoppers can be readily controlled with l/k pound of dieldrin or 1 l/2 pounds of 

 toxaphene per acre. When using dieldrin, allow 60 days to elapse between treat- 

 ment and harvest of corn. If dairy pasture or forage must be sprayed, use 1 

 pound of malathion, but do not pasture or harvest for 7 days after treatment. For 

 best results, make the applications in the late afternoon or early evening. Toxa- 

 phene may be used on forage crops to be fed non-dairy animals, provided they are 

 removed from the forage six weeks before slaughter. 



Adult spittlebugs and cloverleaf weevils . These insects are concentrat- 

 ing in this year's legume seedings. The eggs they deposit this fall will produce 

 the populations that will be seen in fields next spring. New seedings are most 

 likely to be damaged by these insects next spring, particularly in the northern 

 sections and along the eastern edge of the state. To avoid damage to the first 

 cutting of hay next spring, apply DDT at 1 l/2 pounds per acre during the last few 

 days of August or into the first 10 days of September. Plant hugs are also reduced 

 by this treatment. Forage crops treated with DDT should not be fed to dairy cattle 

 or to livestock being fattened for slaughter. Fall-treated forage may be grazed 

 or cut for hay or silage for livestock next spring. 



Our thanks and our compliments to all who have supplied information for 

 this "bulletin during the i960 growing season. We hope you will join us again next 

 year in an effort to outsmart the insects. 



This weekly report was prepared by Steve Moore III, Illinois Agricultural 

 Extension Service and Illinois Natural History Survey, in cooperation with the USDA 

 Plant Pest Control Branch, from information gathered by entomologists and coopera- 

 tors who send in weekly reports from their own localities. 



SM:df 

 8/19/6O 



