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Black cutworms continue to be a problem in cornfields in the northern one- 

 third to one -half of the state. In estimating damage, remember that over half of the 

 damaged small plants will recover rapidly, as they are usually cut off above the grow- 

 ing point. Only when they are cut off below the growing point will they die. Make 

 counts to determine stand losses. Worms that are 1/4 to 1/2 inch long will feed for 

 another 7 to 10 days; worms 1 l/2 to 2 inches long have almost finished feeding. 

 Base the need for protective treatment on the damage, location of growing point in 

 relation to cut on plant, and length of time the worms will continue to cut. If post- 

 planting treatment is needed, use either l/2 pound cf actual dieldrin or 3 pounds of 

 actual toxaphene. Concentrate the spray at the base of the plants. The more water 

 you use per acre, the better the results will be. If possible, cultivate immediately 

 to cover the spray deposit. Do not use dieldrin or toxaphene on dairy farms or allow 

 the drift to reach dairy pastures or hay crops. For dairy farms, use 2 pounds of ac- 

 tual carbaryl per acre. It will be helpful, but not highly satisfactory. If replant- 

 ing is necessary, apply a broadcast application of a soil insecticide. 



Do not expect a spectacular kill of cutworms overnight. Compute control 

 three or four days after treatment. Do not look for dead worms, since they soften 

 and disintegrate rapidly as soon as they die. You may find only a spot of slimy mud 

 where a dead worm has been. Evaluate kill of cutworms by new damage and presence of 

 live worms. 



Sod webworm damage to corn appears in cutting of the plants or ragging of 

 the leaves. These worms are common in corn after grass sods. Close examination of 

 damaged plants will show webbing, and in a webbed-up mass of dirt you will find a 

 spotted, gray to brown worm. If an insecticide spray is indicated, use toxaphene or 

 carbaryl. It is doubtful that control will be required at this late date. 



Southern corn rootworm adults seem to be more numerous in cornfields than 

 in the past few years. This insect is also called the spotted cucumber beetle. It 

 migrates from the south and deposits eggs in cornfields. The white larvae that hatch 

 from these eggs feed on the roots of the corn. If infestations are severe and the 

 roots are destroyed, the plants will tip over. Do not confuse this pest with the 

 northern corn rootworm, which winters in Illinois and is a root pest of continuous 

 corn. 



Controls are not recommended for either of these pests at this time. 



Chinch bugs are still hatching, but the beating rains are continuing to 

 kill them. However, in the eastern Illinois area from Joliet to Bloomington to 

 Paris, examine thin stands of grain, particularly in areas missed by the continual 

 hard rains of the past two weeks. 



Potato leafhoppers have been abundant in some fields of alfalfa, particu- 

 larly those that are being cut late. The damage shows in yellowing of the leaves and 

 is usually quite apparent. The tiny wedge-shaped, fast-moving green insects can be 

 found by shaking the plants over a piece of paper. No control is recommended. 



Bean leaf beetles are feeding on soybeans. We have an occasional report of 

 severe defoliation. If it is necessary to protect the stand, apply toxaphene or 

 carbaryl. 



