Southwestern com borer is abundant in bottomland fields of very late corn in the 

 southern tip of Illinois. Now is the time to apply insecticides. If 25 percent 

 of the whorls show feeding from this borer and small borers are found in the whorl, 

 apply either 1 to 2 pounds of actual diazinon or 2 pounds of carbaryl (Sevin) per 

 acre. If applying by air, use granules; they will roll into the whorls and get in 

 behind the leaf sheaths. Some states also recommend EPN granules. With diazinon 

 granules, wait 10 days before harvesting the crop. There is no time limit on the 

 use of carbaryl. There is a 14-day waiting period when using EPN. 



Corn flea beetles are extremely abundant in cornfields in the southern half of 

 Illinois. Their feeding alone is not of importance, but they could be transmit- 

 ting Stewart's disease or blight. This will appear as brown, dry, lower leaves 

 within the next few weeks. Control of flea beetles now will not reduce the inci- 

 dence of disease, so no control is recommended for flea beetles. 



Fall armyworms are present in some late-maturing cornfields. The dull-green to 

 brown, smooth- skinned worms feed in the whorl, leaving ragged holes in the leaves. 

 Several plants in one area will be damaged, and there is usually only one worm 

 per plant. The worms were about half grown this week in the south-central section. 

 IVhen mature, the worms drop to the ground and pupate in the soil. Unless the field 

 is heavily infested (25 percent or more) , treatment is not profitable. If the in- 

 festation is severe and the worms still present, carbaryl or toxaphene at 1-1/2 

 pounds per acre as granules will give control. Do not feed toxaphene- treated corn 

 as forage to dairy cattle or to livestock fattening for slaughter. The corn grain 

 may be fed. 



Cattail caterpillars --orange- striped, brown and black, bristly worms- -are present 

 in some fields of corn. They feed along the leaf margins, chewing out large areas 

 similar to grasshoppers. Seldom are they numerous, probably because a wasp para- 

 sitizes many of the worms and kills them. No control measures have yet been nec- 

 essary. 



Soybeans 



Green cloverworms continue to be a problem in many soybean fields, particularly in 

 the northern two -thirds of the state. All sizes of worms are present, but many of 

 them still tiny. They strip the leaves --especially the newer, more-tender top 

 leaves, but do not attack the pods or blossoms. Severely damaged fields take on 

 a grayish to whitish cast. Damage is most severe if defoliation occurs when the 

 pods are half filled. Most beans are now in the early pod- forming stage. A few 

 parasitized worms were observed this week, but in general, the worm populations 

 are healthy. 



Treatment is justified if there are 6 or more worms per linear foot of drill row 

 during the period of pod development. This is particularly true if 25 percent of 

 the leaf surface has already been eaten. To determine the field average, shake 

 the plants vigorously over the center of the row and count the worms in several 

 places in the field. Use 1 pound of carbaryl (Sevin) or 1-1/2 pounds of toxaphene 

 per acre to control this insect. Toxaphene is slow-acting, so wait about 4 days 

 after spraying before judging its effectiveness. The beans should not be harvested 

 for 21 days after spraying with toxaphene. Do not feed toxaphene- treated soybeans 

 as forage to dairy animals or to livestock being fattened for slaughter. Carbaryl 

 has no waiting period or feeding restrictions. 



