-2- 



(Sevin) at 5/4 pound or toxaphene at 1-1/2 pounds of actual chemical per acre sprayed 

 over the row will control them. Do not feed corn treated with toxaphene as ensilage 

 or stover to livestock. 



Corn leaf aphids are heavy in some fields in east-southeast Illinois and in occasional 

 fields in other areas. Fields in pretassel have the most aphids. In general, corn 

 leaf aphid populations are light, and in many fields the population has decreased as 

 tassels emerged. A widespread outbreak of these aphids is not expected this year. 

 However, there will continue to be occasional fields where aphids build up to damaging 

 numbers . 



In pretassel fields, if 50 percent or more of the plants have moderate numbers of 

 aphids, treatment is justified. Apply the treatment just after tassels begin to show. 

 In more mature fields, if 15 to 20 percent or more of the plants are heavily loaded 

 with aphids (top third blackened) and the corn is under stress, treatment is also 

 profitable. 



For control, apply 1 pound of malathion or diazinon or 1/4 pound of methyl parathion 

 per acre as a spray. Allow 5 days for malathion, 10 days for diazinon, and 12 days 

 for methyl parathion between treatment and harvest for grain, ensilage, or stover. 

 Methyl parathion should be applied by experienced applicators. 



European corn borer moths are laying eggs on late-maturing corn. Egg-laying will 

 continue in southern Illinois for another week or two; in central Illinois for another 

 2 to 5 weeks and in northern Illinois for another 5 to 4 weeks. In southern and south- 

 central sections, a third generation in late August and early September is likely. 

 The moths will tend to concentrate their egg-laying in fields in the late-whorl to 

 early-silk stage. 



If corn is in the whorl stage and if 75 percent or more of the plants are showing 

 recent whorl feeding, apply carbaryl (Sevin) or diazinon granules. If the corn has 

 tasselled, look for egg masses. If the average is 1 or more egg masses per plant, 

 apply an insecticide. Aerial sprays on tasselled corn are effective, but on whorl- 

 stage corn, aerial applications should be granules--not sprays. Use 1-1/2 pounds of 

 carbaryl (Sevin), 1 pound of diazinon, or 1/2 pound of parathion per acre. (Allow 

 10 days for diazinon and 12 days for parathion between application and silage removal.) 

 Parathion should be applied only by experienced applicators. No waiting period is 

 required for carbaryl. 



Grasshoppers continue heavy in some areas, and migrations into corn and soybeans 

 are occurring. For control, use either 3/4 pound of carbaryl (Sevin) or 1-1/2 pounds 

 of toxaphene per acre. Do not apply toxaphene to corn or soybeans to be used as 

 forage for livestock. Do not apply toxaphene near fish-bearing waters or carbaryl 

 near bee yards. 



STORED GRAIN INSECTS 



Heavy infestations of Indian meal moth were observed in untreated wheat this week in 

 southern Illinois. No meal moths were as yet present in wheat treated with malathion 

 as a dust or spray. The Indian meal moth larva, which is yellow and about 3/8 inch 

 long, webs several kernels of wheat together. These clumps of webbed kernels can be 

 found on the surface of the grain or clinging to the side walls of the bin. The 

 larva transforms to a brown, torpedo -shaped pupa (1/4 inch) from which the small 

 copper -colored moth emerges. Small moths flying over the surfaces are also a sign of 

 infestation. 



