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Stands in most wheat fields are not thick enough to attract and provide good sur- 

 vival for armyworms. In the central and south-central sections, the worms are 

 still small (1/4- inch), and it is more difficult to assess the situation. Treat- 

 ments will not be needed in this area until about May 31 or after. 



Damage from mice or other rodents is noticeable in wheat fields. They cut the 

 stems in 3- to 4- inch lengths and leave them in piles. This is not the work of 

 armyworms. They strip the leaves and beards and sometimes cut the stem just be- 

 low the head. 



The find armyworms, examine lodged spots or the thick, rank areas first. Shake 

 the plants vigorously, and look on the ground for the worms. 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 these spots, no further examination 

 is necessary. If you find lots of them, make several additional counts over the 

 entire field. No control is needed unless the population averages 6 or more per 

 linear foot. Even then, do not apply insecticides until most of the worms are 

 over one-half inch long. 



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

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

 animals or livestock fattening for slaughter. Do not contaminate fish-bearing 

 waters with toxaphene. 



We have recommended against dairy farmers using chlorinated hydrocarbons on their 

 farms. Toxaphene belongs to this group of chemicals. However, the official label 

 permits its use on dairy farms. If it is used on or adjacent to dairy farms, avoid 

 drift onto pastures and hay crops. 



Carbaryl (Sevin) , 1 pound per acre, may be applied to grain fields adjacent to 

 dairy pastures, but not after the heads have begun to appear. Use carbaryl on 

 grass pastures or hay fields if armyworms are extremely abundant, but warn area 

 beekeepers that you are applying carbaryl. Trichlorfon (Dylox) , an organic phos- 

 phate insecticide, at 3/4 pound per acre, may be used to within 21_ days of harvest, 

 but the straw should not be used for livestock feed. 



Corn Insects 



Flea beetles are numerous in many cornfields and more widespread damage was ob- 

 served this week. Small corn should be watched for the presence of small, shiny, 

 black beetles that jump readily when disturbed. They strip the green from the 

 surface of the leaves, leaving white stripes. 



These beetles may transmit a bacterial -wilt disease (Stewart's disease) to corn 

 which can reduce yields. Disease symptoms do not usually show on field corn until 

 late summer. 



Damage is most severe on corn under 10 inches high. If damage is severe and plants 

 are being killed, apply 3/4 pound of carbaryl (Sevin) , or 1 1/2 pound of toxaphene 

 per acre as a band spray over the row. 



Only scattered reports have been received of black cutworms damaging corn. Check 

 cornfields regularly; watch for missing plants, cut plants, or wilting plants. 

 If the stand is being threatened, apply 3 pounds of toxaphene, 2 pounds of carbaryl 

 (Sevin) , 2 pounds of diazinon (granules preferred and cover by cultivating) , or 



