COLLEGE OF 

 AGRICULTURE 

 UNIVERSITY OF 

 ILLINOIS AT 

 URBANA-CHAMPAIGN 

 AND NATURAL 

 HISTORY SURVEY 

 URBANA. ILLINOIS 



NSECT WEED & PL A NT DISEASE SURVEY BULLETIN 



TATE/COUNTY/LOCAL GROUPS/U.S. DEPARTMENT OF AGRICULTURE COOPERATING 



FOR IMMEDIATE RELEASE 



No. 11, June 1, 1973 



This series of weekly bulletins provides a general look at the insect, weed, and plant 

 disease situation (fruit and aommeroial vegetables excepted) , along with suggested 

 abbreviated, control measures. Each individual should check his own fields to deter- 

 mine local conditions. 



INSECTS 









CORN INSECTS 



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1973 



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Black cutworms are reported to be damaging corn in west -southwestern Illinois. Watch 

 fields closely for cut or missing plants --a sign that cutworms are at work. Dig around 

 the base of the plants to find the worms. If you find 1 or more worms per 25 plants, 

 apply controls immediately. 



For control, broadcast 20 pounds of 5-percent carbaryl (Sevin) on apple-pomace bait per 

 acre. Spray of 2 pounds of carbaryl and 2 quarts of molasses plus water per acre banded 

 at the base of the plants are also effective. Commercially prepared spray baits con- 

 taining carbaryl plus Tractum or molasses are available. Trichlorfon (Dylox) at 1 

 pound per acre as a spray will control black cutworms. Use 20 gallons of water per 

 acre when band spraying with trichlorfon, then cultivate in order to throw soil over 

 this band in the row. 



True armyworms have been damaging newly emerging corn planted without tillage on grass 

 sod , according to reports . The worms were found hiding in soil cracks and debris dur- 

 ing the sunny part of the day. A spray of carbaryl (Sevin) or toxaphene applied at 

 1-1/2 pounds of actual insecticide per acre is effective. If most of the grass between 

 the rows is dead, band the spray over the row. If there is still some green grass be- 

 tween the rows, use a broadcast spray treatment to kill any armyworms that may still 

 be feeding on the grass. Do not feed toxaphene -treated corn as forage to dairy or 

 beef cattle. There are no restrictions for carbaryl. 



Common stalk borers are damaging no-till com on grass sod. These striped worms with 

 a purple band around their middle feed deep in the whorl. The damaged leaves that 

 emerge are extremely ragged. Ordinarily this pest is serious only in the marginal rows 

 of conventionally tilled corn, but in no -till corn the infestations often cover the en- 

 tire field. 



Control is difficult because the worm is protected inside the corn plant. A spray of 

 carbaryl at 1 to 2 pounds per acre directed over the row may be helpful. As the borer 

 leaves one plant and crawls to another, it will contact the insecticide and be killed. 



European corn borer moths are emerging in the southern section (about 40 percent emer- 

 gence) , and egg-laying is starting. First-generation corn borers are not expected to 



