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To find armyworms in wheat fields, first examine lodged spots. Shake 

 the plants vigorously, and look on the ground underneath. If small, striped worms 

 are present, they will probably be armyworms. Do not use this count as a field 

 average. If you find no armyworms in lodged spots, no further examination will 

 be necessary. If you find lots of them, make a field check. No control is needed 

 unless the field population averages six or more per linear foot. Even then, do 

 not apply insecticides until most of the worms are over one-half inch long. 



Do not confuse the striped armyworms with the transparent yellow to green 

 sawflies . An armyworm has five pairs of abdominal prolegs; sawflies, six or more 

 pairs. Sawflies do not damage wheat plants enough to require control. 



Apply 1 1/2 pounds of toxaphene for armyworm control in small grains. 

 There are no restrictions on use of grain. Do not feed the straw to dairy animals 

 or livestock fattening for slaughter. Do not apply toxaphene to fields adjacent 

 to dairy pastures or hay crops. Do not contaminate fish-bearing waters with toxa- 

 phene. We have suggested that dairy farmers not use chlorinated hydrocarbons on 

 their farms. Toxaphene belongs to this family of chemicals. However, the offi-r 

 cial label permits its use on dairy farms. If it is used on or adjacent to dairy 

 farms, avoid drift onto pastures and hay crops. Trichlorfon (Dylox) , an organic 

 phosphate insecticide at 1 pound per acre, may be used to within 21 days of har- 

 vest, but the straw cannot be used for livestock feed. 



Malathion, 1 lA pounds per acre, may be beneficial for armyworm con- 

 trol in areas where drift may be critical. It may be used on grass pastures and 

 hay right up to the day of harvest. Allow one week to elapse between application 

 and harvest of grain. 



Examine grassy pastures and hay fields. If armyworms are extremely 

 abundant and devouring the grass, apply 1 pound of carbaryl (Sevin) per acre. 

 There is no waiting period between application and harvest. Warn beekeepers that 

 you are applying carbaryl. 



Wheat growers often panic at the word armyworm. Do not be stampeded 

 into applying insecticides unless necessary. This year the wheat may be mature 

 enough to keep the leaf stripping of armyworms from affecting yield, and the worms 

 may be forced to migrate. If migration occurs, watch adjacent crops. However, 

 as the leaves mature, the worms may begin to feed on the stems, causing the heads 

 to fall to the ground. 



Also remember that small armyworms do little damage. The worm eats 

 about 80 percent of its food after it is over 3 A inch long. 



Two factors may help this year. Armyworms are killed more rapidly by 

 diseases when temperatures are high. Since armyworm development is about 10 days 

 later than normal, this disease may be a factor. If you find dead, soft, mushy- 

 looking worms, they have died from this disease. Watch for little white capsules 

 on the backs of armyworms. These capsules are fly eggs, and the maggot that hatches 

 penetrates the body of the worm, killing it. Predatory insects are also numerous 

 in wheat fields and are killing some armyworms. 



Upcoming Farm Insect Problems 



Corn borer moth emergence has reached 20 percent in the extreme south; 

 pupation in central Illinois has reached 1+0 to 50 percent, and first emergence oc- 

 curred this week. In northern Illinois, no pupation or moth emergence has occurred. 



