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FOR IMMEDIATE RELEASE May 20, i960 



INSECT SURVEY BULLETIN NO. 5 



This is the fifth in a series of weekly bulletins on the general insect 

 situation in Illinois (fruit insects excepted), prepared by entomologists of the 

 Illinois Natural History Survey, University of Illinois College of Agriculture, and 

 cooperating agencies. It is designed to forewarn people in Illinois of impending 

 changes in insect activity and suggests abbreviated control measures. These reports 

 indicate only general trends. Each individual should check his own fields to deter- 

 mine local conditions. 



General conditions ; White, seared-appearing leaves on alfalfa plants are 

 the result of frost injury several days ago, and not insect attack. Actually, in- 

 sect activity has been retarded this week by cool weather and rain. 



Spittle bugs : Populations this week varied from 20 to 200 per 100 stems 

 of clover and alfalfa in northern Illinois. It is almost too late to get excellent 

 control now, but practical control may still be obtained with 1 pound of methoxy- 

 chlor per acre. Do not apply within one week of pasture or harvest. 



Clover leaf weevil : Leaf feeding by these insects is apparent now on 

 clover, but the larvae that did the damage are nearly mature. In addition, a fungus 

 disease is beginning to kill many of the larvae. 



Pea aphids : These aphids are becoming common on red clover as well as 

 alfalfa. However, there was no visible damage this week. Lady beetles and their 

 larvae, both feeding on aphids, are becoming more plentiful and are helping to hold 

 aphids in check. A fungus disease is also killing many of these aphids. Muggy 

 weather favors this disease. Thus we are not anticipating any large-scale damage 

 from these insects. 



Lesser clover leaf weevil : These tiny worms are now common throughout 

 Illinois and are burrowing in stems and heads of clovers. No control measures are 

 known. 



Corn borer : Pupation of overwintering borers has begun in central and 

 north-central Illinois. First moth emergence will probably occur in about three weeks. 



Soil insecticides for corn : Many people are asking whether the use of 

 soil insecticide, aldrin or heptachlor, is justified with the delayed planting of 

 corn that is occurring. Soil temperatures are low and soil insect activity will 

 not increase until soil temperatures rise. We recommend the use of soil insecticides 

 even on later planted corn. 



Bagworms : These insects will soon be hatching in the southern third of 

 the state. After hatch is complete, apply a spray made with 2 teaspoons of the 57$ 

 malathion concentrate, 3 teaspoons of 60$ toxaphene, or 1 tablespoon of lead arsenate 

 per gallon of water. A second application two weeks later may be needed. 



Caution : Before applying insecticides, read labels carefully and follow 

 all precautions. This not only will insure personal safety, but also will eliminate 

 insecticide residue hazards. 



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This weekly report was prepared by H. B. Petty, Illinois Agricultural Ex- 

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

 Agricultural Service, Plant Pest Control Branch, from information gathered by ento- 

 mologists and cooperators who send in weekly reports from their own localities. 



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