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Grasshoppers are numerous in occasional hay fields and heavy along some 

 roadsides, ditch banks, and fence rows. Most of the eggs should have hatched by 

 now. Hot, dry weather is favorable to grasshopper development. If 'hoppers are 

 numerous , spray immediately before they have a chance to migrate to corn or soy- 

 beans. 



Carbaryl at 3 A pound per acre as a spray is best for grasshoppers. Di- 

 azinon at 1/2 pound, malathion at 1 pound, and naled (Dibrom) at 3A pound per acre 

 are also effective. When treating forage crop fields, allow 10 days between treat- 

 ment and harvest with diazinon and k days with naled. There is no waiting period 

 for carbaryl or malathion. 



Potato leafhoppers are small wedge-shaped green insects that suck the sap 

 from alfalfa as well as from potatoes. Damaged alfalfa is yellow to purple and 

 stunted. The yield of damaged alfalfa, may be close to that of undamaged alfalfa, 

 but the quality is quite different. Damaged alfalfa makes stemmy, poor-quality hay. 



Damage from this pest is now showing up in southern Illinois on second- 

 cutting alfalfa. After damage is apparent, cutting is the only answer, since the 

 damaged growth will not recuperate. The new shoots will grow normally after cut- 

 ting. If leafhoppers are numerous and damage is not yet apparent, apply 1 pound of 

 methoxychlor or carbaryl per acre. Do not harvest or pasture for one week if 

 methoxychlor is used. There is no waiting period with carbaryl. 



Alfalfa weevils have been found for the first time in 36 counties. At 

 present , the weevil is as far north as Hancock County in western Illinois and Lake 

 County in eastern Illinois. The northernmost counties where the weevil is present 

 include Hancock, McDonough, Knox, Henry, Bureau, LaSalle, DeKalb, Kane, and Lake. 

 Since the spring of 196U when it was first found in Illinois, it has spread into 

 83 counties (four-fifths of the state). We expect it to spread into the remaining 

 counties by next year. Economic damage can be expected on alfalfa in much of the 

 southern half of Illinois in 19 67. 



Wasp parasites of the alfalfa weevil have been released in various areas 

 for two years with the hope they will establish and help as a natural force to sup- 

 press alfalfa weevil populations. It is too soon to evaluate this program. 



Upcoming Farm Insect Problems 



Corn leaf aphids can be found in the whorl of corn. Colonies are estab- 

 lishing but as yet numbers are not heavy. Aphids can also be found in small numbers 

 in grassy weeds like foxtail and will soon move to the corn. It is too soon to pre- 

 dict overall abundance and problems with this insect. 



Corn borer moths are emerging in the southern tip of Illinois. This moth 

 emergence will continue for at least another 2 to 3 weeks. The moths will deposit 

 eggs for a second generation in fields in pretassel to early silk. 



Pupation has begun in south-central Illinois, and emergence of moths will 

 begin in about another two weeks. 



Moth emergence for the second generation in northern Illinois will not 

 take place until early August. 



Black cutworm and true armyworm moths have been heavy in light traps the 

 past three weeks. Thus far no problems have been observed or reported. 



