-U- 



Periodical cicada , or 17-year locusts, are due to emerge in an area 

 ■bounded by a line from Vermilion to Knox to Scott to Montgomery to Vermilion county. 

 This particular brood was numerous in 19^9, and the nymphs have remained in the 

 ground, sucking the sap from tree roots. The adult cicadas prefer oak, hickory, 

 apple, peach and pear trees and grapevines for laying eggs. Damage occurs when the 

 females make slits in branches and twigs in which to deposit eggs. These small 

 twigs and branches turn brown, die and sometimes break off. The young nymphs that 

 hatch crawl into the soil for another 17 years. 



Protect tender small trees and shrubs by enclosing them in cheesecloth 

 or mosquito netting. Cicadas can be controlled by spraying with carbaryl (Sevin) 

 about every six days while cicadas are present. Mite problems may develop with 

 repeated spraying of carbaryl. Malathion can be used in conjunction with carbaryl 

 to help prevent a mite buildup. 



Bagworms are now hatching in central Illinois. For best control, plan 

 to spray evergreens this weekend in the central area. The eggs will all be hatched 

 by then, and the worms will still be small (June 18 and 19). June 30 is the target 

 date for bagworm sprays in northern Illinois . Spraying should already be under way 

 in southern Illinois, Carbaryl (Sevin), malathion, diazinon or lead arsenate is 

 effective as a spray. Follow label directions, and check the plants that may be 

 injured if sprayed with the insecticide you are using. 



Iris borers - If you have a history of problems with iris borers in iris, 

 treat now with dimethoate (Cygon), using k teaspoons of the 25% emulsifiable con- 

 centrate per gallon of water. Spray leaves thoroughly and exposed roots to the 

 point of runoff. 



Caution to Those Using Insecticides 



Before applying insecticides, read the labels carefully and follow all 

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

 residue hazards. 



********** 



This weekly report was prepared by K. B. Petty, Steve Moore, Roscoe 

 Randell, Don Kuhlman and Clarence E. White, Illinois Natural History Survey and 

 University of Illinois College of Agriculture, in cooper: tion with the USDA Agri- 

 cultural Research Service, Plant Pest Control Branch, from information gathered 

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

 ties . 



Sent by: H. B. Petty 



Extension Specialist 

 in Entomology 



HBP:SM:RR:DK:CEW:bl 



