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Use 1 pound of actual diazinon in granular form per acre or 1-1/2 pounds of carbaryl 

 (Sevin) as granules. For spraying, use the same amount of actual insecticide per 

 acre, and direct the spray to the upper third of the plant. Aerial applications shoulc 

 be granules, not sprays or dusts. Allow 10 days between treatment and the ensiling of 

 corn when applying diazinon; carbaryl has no waiting period. Commercial applicators 

 may prefer to use parathion at 1/2 pound actual per acre, which will provide good con-; 

 trol of the corn borer. Parathion has a 12 -day waiting period between treatment and 

 harvest. 



Southwestern corn borers in the extreme southern counties usually follow the pattern 

 of the European corn borer. The number of southwestern borers is usually not serious 

 until the second and third generations --from late July through September. No chemical 

 control is recommended at this time. 



Corn leaf aphids may be around this year . Some are already present . They certainly 

 have a wide selection of planting dates from which to choose. No control is recommends 

 as yet. 



Armyworm moths --the brown or buff-colored, heavy-bodied moths- -will become numerous 

 within the next three to four weeks. They will be emerging from wheat fields in centra 

 and southern Illinois, where these worms were generally found. A few moths have alreac 

 appeared. Cornfields with grassy weeds should be checked during late July and August 

 for infestations. No control is needed now. 



Cutworms are maturing rapidly. Corn that was cut off above the growing point is grow- 

 ing back; but in corn that was planted early, cutting was below the growing point and 

 the plants died. Most worms are now 1-1/2 inches long or more, and will be pupating 

 and emerging as moths later. Our fear is that with the wet weather, the moths that 

 emerge from fields infested early may soon deposit their eggs in low spots within othei 

 fields. If this happens there could be serious damage. This is more likely to happen 

 in northern Illinois than in the central or southern sections, since these moths tend 

 to migrate northward. i 



If plants are still being cut above the growing point and if worms are larger than 1 

 inch, the outbreak will be over shortly and the corn will continue to grow. However, ; 

 immediate treatment is needed if the plants are being cut below the growing point and 

 if many of the worms are less than an inch long. Use a spray --directed at the base 

 of the plants --of carbaryl (Sevin) at 2 to 3 pounds, diazinon at 2 pounds, toxaphene 

 at 3 pounds, or trichlorfon (Dylox) at 1 pound of actual chemical per acre. It is 

 best to use at least 20 gallons of water per acre and to cover the spray band by 

 throwing soil at the base of the plants with a cultivator. 



Corn rootworm eggs are now hatching. If you expect a rootworm infestation but did 

 not use a rootworm insecticide at planting time, make a basal application as soon as 

 you can get into the field. 



As a result of the recent rains , we do not know whether the rootworm insecticides 

 applied at planting will provide the usual control; also, whether the water standing 

 in the fields has drowned some rootworms . Where the corn is still short, you can 

 check for a basal application in about a week; where the corn is tall, it is already 

 too late . 



In general, in fields where a rootworm insecticide was applied at planting time, no 

 basal application will be needed, unless there has been excessive soil erosion. For 

 a basal application we suggest BUXten, Dasanit, or phorate (Thimet) . 



