in the vicinity of the ear zone. Occasionally the eggs are laid on the upper 

 sides of the leaves. Egg masses are white when first laid and about 1/4 inch in 

 diameter. 



To decide whether to apply an insecticide, count the egg masses on several plants 

 in several locations in the field. Observe each leaf closely. If the average is 

 one or more egg masses per plant, treatment may be profitable to prevent extensive 

 stalk breakage and ear dropping. Use 1 pound of actual diazinon or 1 1/2 pounds 

 of actual carbaryl (Sevin) per acre as granules or sprays. When using diazinon, 

 allow 10 days before making ensilage or stover; carbaryl has no waiting period. 



Corn leaf aphids are rapidly declining in population or have completely disappeared 

 in fields where pollen shed is complete and silks are drying. In a few fields, 

 the aphids are not disappearing but are dropping down from the tassels and coloniz- 

 ing on the silks and lower leaves. Late-planted fields where a few tassels are 

 beginning to emerge should be checked for an infestation. 



Treatment is justified for corn in the whorl stage if 50 percent or more of the 

 plants have some aphids with a few tassels severely infested. Treatment in the 

 early tassel to pollinating stage is justified if 15 percent or more of the plants 

 are heavily loaded with aphids . 



Several different caterpillars have been observed feeding in corn silks and on 

 ear tips. These include fall armyworms , true armyworms , corn earworms , corn 

 borers , and loopers . Damage is not apparent. 



Fall armyworms are present in an occasional late -maturing cornfield. The dull- 

 green to brown smooth- skinned worms feed in the whorl o\~ the plant, causing a 

 ragged appearance. In many fields the larvae have already matured and left the 

 plants. Be sure the worms are still present before applying control measures. 

 Carbaryl or diazinon granules should control worms in the whorl. For diazinon, 

 allow 10 days between application and harvest as ensilage or stover. There is 

 no waiting period for carbaryl. Toxaphene granules can be used if the corn is 

 to be used only as grain. 



Soybean Insects 



Heavy grasshopper populations were noted in some areas in fence rows, ditch banks, 

 and roadsides. They will continue feeding in these areas until the food supply 

 is exhausted and then migrate into adjacent corn and soybean fields. If 'hoppers 

 are numerous , spray immediately before they have a chance to migrate to corn or 

 soybeans . 



Carbaryl (Sevin) at 3/4 pound per acre as a spray is best for grasshoppers. Diazi- 

 non at 1/2 pound, malathion at 1 pound, and naled (Dibrom) at 5/4 pound per acre 

 are also effective. When treating forage crops, allow 7 days between treatment 

 and harvest with diazinon, 4 days with naled. There is no waiting period for 

 carbaryl or malathion. 



Green cloverworms are present in soybean fields in southern, central, and northern 

 sections. Numbers are still low, but the situation deserves careful attention. 

 These pale-green worms with white stripes will defoliate the plants. They "spring" 

 or jump by rapidly curling and uncurling their bodies. 



