FOR IMMEDIATE RELEASE August 4, 196l 



INSECT SURVEY BULLETIN NO. 16 



This weekly bulletin on the general insect situation in Illinois (fruit 

 insects excepted) is prepared by entomologists of the Illinois Natural History Sur- 

 vey, University of Illinois College of Agriculture and cooperating agencies. It is 

 designed to forewarn people in Illinois of impending changes in insect activity and 

 to suggest abbreviated control measures. These reports indicate only general trends. 

 Each individual should check his own fields to determine local conditions. 



Bean leaf beetles are eating holes in soybean leaves. These red, green or 

 yellow beetles usually have four black spots on their backs. They drop off the plants 

 with the slightest disturbance and for this reason are difficult to find. Ordinarily 

 they feed on the leaves but on occasion will chew on blossoms and pods. 



Grasshoppers have reported to be feeding on soybean blossoms. In this case 

 control may be profitable, since »boppers also feed on pods and leaves. Other in- 

 sects, mainly the green clover worm , the alfalfa webworm and the garden webworm , may 

 be eating the soybean foliage. For overall control of these soybean insects, apply 

 1 1/2 pounds of toxaphene or l/k pound of dieldrin per acre. Allow l)-0 days to elapse 

 between an application of dieldrin and harvest. Do not feed toxaphene- treated for- 

 age to dairy animals or animals being finished for slaughter. 



First- generation corn borer populations throughout the northern half of 

 Illinois are about the same as those of i960. It is too early to determine the per- 

 centage of first-generation borers that will pupate. 



Face fly populations leveled off during July but may increase rapidly with 

 moisture and heat. DDVP face fly baits applied daily have controlled this pest. 

 Apply the bait on the forehead of the animal. Apply to an area about 1 inch wide 

 and 6 inches long. 



For non-dairy cattle that can not be nancued, 5$ toxaphene in backrubbers 

 have been giving some relief, The effectiveness of this method depends entirely on 

 how much the cattle use the backrubber. Where the problem of use exists, study the 

 situation carefully to determine what type of backrubber to use and where to locate 

 it. If animals do not use a backrubber, try putting treated rolls of burlap bags on 

 a tree that they use as a rubbing post. Even when properly located, backrubbers must 

 be recharged about once a week for best results. When using toxaphene, do not 

 slaughter animals for 28 days after treatment. 



Cicada killer wasps have attracted lots of attention during the past few 

 weeks. These wasps are about 1 l/2 inches long, yellow and brown and vicious look- 

 ing. They can inflict severe stings but will not do so unless molested. They seek 

 out cicadas, paralyze them by stinging, and take them to a burrow in the ground. They 

 then insert an egg which hatches into a wasp grub that feeds inside the cicada. 



To control these insects, apply a 2 to 3$ chlordane solution in the burrow 

 after dusk , and then stop up the hole with dirt. A tablespoon of carbon tetrachloride 

 in each burrow can be used in place of the chlordane. 



