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Bagworms are a common pest in Illinois on both evergreen and deciduous 

 trees and shrubs. Evergreens defoliated by this insect usually die. Bags hanging 

 from trees and shrubs during the winter produce many larvae the following season. 

 These larvae emerge in the southern part of Illinois at the end of May, in central 

 Illinois the first week or two in June and in northern Illinois at the end of June. 

 Sprays applied now in the southern areas of the state will not be effective. 



To control small to one-half grown bagworms, spray with 50-57 percent 

 malathion emulsion concentrate, carbaryl or diazinon at the rate of 2 teaspoons per 

 gallon of water, or 1 quart per 100 gallons of water. You may use 1 tablespoon of 

 lead arsenate per gallon of water. Now is the time to spray in the north-central and 

 northern parts of the state. Large infestations of bagworms are difficult to control, 

 but they can be reduced by picking and burning. 



Spruce spider mite . This small insect can do much damage to arborvitae, 

 spruce and juniper by sucking the juices from these plants. When the green color of 

 the plants gives way to gray and then brown, control must be initiated immediately 

 before serious damage occurs . Use either Aramite 15 percent wettable powder at a 

 rate of 2 pounds per gallon of water or dicofol (Kelthane) 18.5 percent emulsifiable 

 concentrate at a rate of 2 teaspoons per gallon or 1 quart per 100 gallons of water. 

 Spray foliage thoroughly, especially the undersides of the leaves. 



Caution to Those Using Insecticides 



Before applying insecticides, read the labels carefully and follow all 

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

 residue hazards . 



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

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

 Illinois College of Agriculture, in cooperation with the USDA Agricultural Research 

 Service, Plant Pest Control Branch, from information gathered by entomologists and 

 cooperators who send in weekly reports from their own localities. 



Sent by: H. B. Petty 



Extension Specialist 

 in Entomology 



