-3- 



Ob serve the occasional early-planted corn that is more advanced than 

 other corn in the area. 



To decide whether an insecticide can he profitably applied, measure the 

 tassel ratio of the field and count the percent of plants with recent whorl leaf 

 feeding. To determine the tassel ratio, measure the height of the plant with 

 leaves extended; split the stalk open and measure from the tip of the developing 

 tassel to the base of the plant. Divide the tassel height by the plant height, 

 and multiply by 100. This figure is the tassel ratio. If the tassel ratio is at 

 least 35 (preferably ^0 to ^5) an d at least 75 percent of the plants show recent 

 whorl feeding, then treatment is justified. Use 1 pound of actual diazinon in 

 granular form per acre or 1 1/2 pounds of carbaryl (Sevin) as granules. For spray- 

 ing, use the same amount of actual insecticide per acre, and direct the spray to 

 the upper third of the plant. Aerial applications should be granules, not sprays 

 or dusts. Follow the label precautions in harvesting and feeding treated corn. 

 DDT can be used as granules or sprays, but not on or adjacent to dairy farms. 



In central Illinois moth emergence is just beginning, while in northern 

 Illinois pupation is just beginning. Continued dry conditions at this time could 

 delay moth emergence and increase the survival of hatching borers, since the corn 

 would then be more mature. However, we are still not expecting severe damage from 

 first-generation corn borer in this northern section. 



Corn flea beetles are present in cornfields in the southern half of the 

 state. They are tiny, shiny black jumping beetles that drop to the ground at the 

 slightest disturbance. They strip the green from the surface of the leaves, 

 leaving white stripes. If plants are being killed, apply 1 l/2 pounds of toxaphene 

 or 3 A pound of carbaryl ( Sevin) per acre as a band treatment over the row. 



Alfalfa leafhopper adults , which have migrated into Illinois from the 

 south, are laying eggs in alfalfa fields. These small, green wedged-shaped insects 

 that skid sideways when disturbed cause yellowing of second and third cutting of 

 alfalfa. They not only cut yields, but also reduce the quality of the hay by 

 lowering its vitamin A and protein content. Wo control measures are recommended 

 at this time. 



The Homeowner's Insect Problems 



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

 to spray evergreens about June 15 in the central area. The eggs will all be hatched 

 by then and the worms will still be small. June 30 is the target date for bagwomi 

 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. 



The following three insects were observed in the central section this 

 week, and control is now timely for this section and the southern section. Wait 

 two weeks in the northern section. 



Oystershell scales have hatched, and the new crawlers are getting ready 

 to set up housekeeping on shrubs like lilac, dogwood, etc. They can be controlled 

 by spraying with malathion. Use 2 teaspoons of the 50-57$ emulsion concentrate 

 per gallon of water. 



