FOR IMMEDIATE RELEASE June 2, 196l 



INSECT SURVEY BULLETIN NO. 7 



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

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

 University of Illinois College of Agriculture and cooperating agencies. It is de- 

 signed 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. 



The armyworm situation has changed this week. Several fields of wheat with 

 damaging numbers of worms have been reported. However, the worms were still small 

 and Just reaching the damaging stage. These reports came primarily from western and 

 southwestern Illinois, but other areas may be affected. It will be well to examine 

 rank growths of grasses and grain for the next few weeks. If there is an average of 

 about six worms (l/2 inch or longer) per linear foot of drill row, treatment may be 

 profitable . 



Toxaphene, 1 l/2 pounds, or dieldrin, l/k pound per acre, is recommended 

 for small grains. Allow 7 days between treatment with dieldrin and harvest, and 

 7 days for toxaphene on wheat but 1^ days on barley. For beef pastures, use toxa- 

 phenej allow k2 days between last grazing on treated pastures and slaughter, particu- 

 larly if toxaphene is being used on the animals to control flies. For dairy pastures, 

 use 2 pounds of methoxychlor or 1 pound of malathion per acre, but do not graze for 

 one week after treatment. 



Flea beetles have affected corn stands in occasional fields in central, 

 western and southwestern Illinois. They strip the green from the leaf surface, 

 leaving only the white tissue. When the beetles are extremely abundant, the damage 

 may be so severe that the leaf, and in some cases the entire plant, dies. If these 

 beetles are stripping the leaves to the point of killing plants, then treatment is 

 recommended . 



Use l/k pound of deldrin or 1 l/2 pounds of DDT per acre as a band spray 

 over the row. 



Sod webworms are killing or seriously damaging some fields of corn, partic- 

 ularly corn after grass sods. They feed below the soil surface, eating on the stalk. 

 Since webworms are concealed in a web to which dirt clings, they are difficult to 

 find. The leaves, upon emerging, are full of holes and often are half eaten. This 

 damage was done when the leaf was in the roll in the stalk. 



DDT as recommended for flea beetles will aid in control, but two nozzles 

 per row should be used. Point them toward the plant. 



Billbugs are snout beetles that drill holes in stalks below ground level. 

 When the leaves emerge, they have a series of holes in them. Occasionally this 

 attack may kill plants. These beetles are being reported primarily from the northern 

 one-third of the state, but may occur in other areas later. Apply DDT as for sod 

 webworms . 



Wireworms have taken some fields of early corn. If the field is to be re- 

 planted, apply 2 or 3 pounds of aldrin or heptachlor per acre, and disk in immedi- 

 ately. The higher rate may be necessary to kill the large wireworms in the short 

 interval between treatment and replanting. 



J UN 



(JM Qi . 



