$? Cooperative Extension Service, University of 



V 



Illinois College of Agriculture in Cooperation With 

 the Illinois Natural History Survey and U.S.D.A. 



FOR IMMEDIATE RELEASE June 17, 1966 



INSECT SURVEY BULLETIN NO. 9 



This ninth weekly bulletin on the general insect situation in Illinois 

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

 College of Agriculture, Illinois Natural History Survey and cooperating agencies, 

 reports general trends in insect activity and suggests abbreviated control meas- 

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



Present Farm Insect Problems 



Armyworms are maturing rapidly and are changing into the pupal stage. 

 Thus a large population of worms may "disappear" almost overnight. Furthermore, 

 the wheat crop is mature enough to make leaf feeding no longer important. 



If armyworms are eating only the leaves on wheat, ignore them. But if 

 they start to cut heads, estimate the population and possible damage, and apply 

 toxaphene if necessary. 



Armyworms migrating from wheat can rapidly strip a cornfield. If they 

 start to migrate into corn, apply 2 pounds of toxaphene or 1 pound of carbaryl 

 (Sevin) per acre to stop the migration and protect the corn. 



There are no re/frictions on use of the grain from toxaphene-treated 

 fields, but do not feed t/' - forage or straw to dairy animals or to livestock fat- 

 tening for slaughter. Cq/'baryl cannot be used on small grains after the boot 

 stage, but it can be used on forage and ensilage crops until the day of harvest. 

 Therefore, we suggest the use of toxaphene on wheat and carbaryl on grass pastures 

 and hay crops. But do not apply toxaphene adjacent to fish-bearing waters. When 

 using carbaryl, notify neighboring beekeepers. 



Black cutworms continue to be a problem in some cornfields. Size varies 

 from small to mature worms that have begun to pupate. Control is erratic, but if 

 the stand is being threatened or low spots in a field are seriously damaged, apply 

 3 pounds of toxaphene per acre and direct the spray at the base of the plants. 

 Cultivate immediately to cover the spray deposit. 



On dairy farms, use 2 pounds of carbaryl (Sevin) per acre. This treat- 

 ment will help to control small worms but will not kill the large ones. 



Results with this insecticide will depend to some extent en soil mois- 

 ture and on rain immediately after spraying. Do not expect a spectacular kill of 

 cutworms overnight. Evaluate control three or four days after treatment. 



European corn borer egg laying and hatch are nearly complete in the 

 southern part of Illinois. The first generation will not be damaging. In the 

 area north of a line from Harrisburg to Carbondale and south of a line from Car- 

 linville to Mattoon, egg laying will rapidly reach a peak and hatching will be 

 complete in about two weeks. A few early, rapidly growing fields may be damaged 

 in this area. 



