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FOR IMMEDIATE RELEASE Ma y 10 > 196 3 



INSECT SURVEY BULLETIN NO. k 



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

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

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

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

 changes in insect activity and to suggest abbreviated control measures. These re- 

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

 determine local conditions. 



Corn borer pupae were observed in central Illinois this week. Pupation 

 started last week in the south central section and two weeks ago in southern Illinois. 

 However, this pest is not expected to present a problem in southern or south-central 

 Illinois . 



The area from Rock Island to Peoria to Quincy had a higher wintering popu- 

 lation than anywhere else in Illinois. Here, pupation will probably start this 

 week, but continued dry weather could delay pupation resulting in late moth emer- 

 gence. If this occurs, corn will be in a stage of growth favoring survival of borers 

 hatching from eggs laid in late June. This situation may warrant careful observa- 

 tion from June 15th through early July. 



Yellow spots in oat fields appeared this week, particularly in western 

 Illinois. Leaf hoppers were associated with these spots, but they were not the cause 

 of the damage. Plant pathologists have identified the cause of the damage as a _ com- 

 bination of two diseases, halo blight and striped blight. Two leaf spots, Helmin- 

 thosporium and Septoria, were also observed. 



Nothing can be done at this time to control these diseases. Favorable oat- 

 growing weather will enable the plants to recover from damage. 



Chinch bugs are still migrating and are now being found in oats as well as 

 wheat and rye fields in the eastern section of Illinois. No eggs have been observed 

 and probably none will be laid for another 10 days or two weeks. 



Armyworms are quite small and so far are only to be found in lodged spots 

 in wheat, barley, and rye fields. 



Elm leaf beetles either now are, or soon will be, skeletonizing leaves of 

 elms, particularly Chinese elms. The larvae are dirty yellow to black, ugly, and 

 spiny. To control, spray the tree with h lbs. of lead arsenate per 100 gallons of 

 water. 



Caution : Before applying insecticides, read the labels carefully and fol- 

 low all precautions. This will not only insure personal safety, but will also elimi- 

 nate insecticide residue hazards. 



This weekly report was prepared by H. B. Petty and Steve Moore, Illinois 

 Agricultural Extension Service and Illinois Natural History Survey, in cooperation 

 with the USDA Agricultural Service, Plant Pest Control Branch, from information 

 gathered by entomologists and cooperators who send in weekly reports from their own 

 loc alit ies . THE UEIMffl OF Tl 



HBP-.gi MAY 14 196; 



5A°/ 6 3 „„• 



