-2- 



If you wait too long to decide to treat, it may be wiser to cut the alfalfa 

 early, remove the hay, and then treat the new growth. 



Clover leaf weevil larvae are also green worms with stripes down their 

 backs, but they feed on clovers and alfalfa during the night and hide in the ground 

 cover during the day. In some instances they are abundant in western and south- 

 western Illinois, but no damage was observed this past week. If the weather re- 

 mains warm, the crops will outgrow the damage and a fungus disease will kill these 

 larvae. 



No control is presently needed. 



European corn borer survival was higher than normal this past winter. 

 The area south of Highway ho had the highest overwintering borer population in 

 Illinois. 



White grubs may injure the roots of crops planted in fields where corn or 

 soybeans were severely damaged last year. These grubs will mature and stop eating 

 by late May or early June. 



If you plant corn in fields that had white grub damage last year, apply 

 up to 3 pounds of actual aldrin or heptachlor per acre and disk it in immediately. 

 If you plant soybeans in such a field, do not use aldrin or heptachlor; wait until 

 after the first week in June to plant beans. 



Spring; cankerworms will be hatching soon and stripping the leaves of elms 

 and other deciduous trees. Often these worms do not even wait for buds to unfold 

 before starting to feed. They may partly or completely strip the foliage in a short 

 time. For best results, spray the tree while the worms are still small with either 

 carbaryl (2 lb. 50% wettable powder per 100 gal. water) or lead arsenate [k lb. per 

 100 gal. water). 



Clover mites are reported to be causing annoyance in some homes. These 

 mites are tiny orange to black, moving specks about the size of the period at the 

 end of this sentence. They cover furniture, walls, window sills, etc., in attempt- 

 ing to find their way outdoors. Pick them up with a vacuum cleaner or use a space 

 spray containing 0.1$ pyrethrin. Before fall, remove grass and weeds next to the 

 foundation, leaving a strip of bare soil at least 18 inches wide. Replanting this 

 strip to such flowers as zinnia, marigold, chrysanthemum, rose, and salvia, which 

 do not attract clover mites, will prevent clover mite problems next year. 



Caution : Before applying insecticides, read the labels carefully and 

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

 eliminate residue hazards. 



* * * * * 



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

 dell, and Clarence E. White, Illinois Natural History Survey and University of Illi- 

 nois College of Agriculture, in cooperation with the USDA Agricultural Service, 

 Plant Pest Control Branch, from information gathered by entomologists and coopera- 

 tors who send in weekly reports from their own localities. 



Sent by: H. B. Petty 



Extension Specialist 

 in Entomology 



HBP:SM:RR:CEW:be 



