Our rule of thumb says if corn leaf aphids are present in moderate numbers on 50 

 percent of the corn plants when the field is in the pretassel to early silk stages 

 and the field is in need of rain, apply diazinon or malathion for aphid control. 



LIVESTOCK INSECTS 



Face fly numbers have increased dramatically during the past two weeks. Counts of 

 10 to 15 face flies per animal in unsprayed herds two weeks ago were common. This 

 week, the counts were 50 to 80 per animal in the same unsprayed herds. 



Horn fly numbers are noticeably low, and stable fly numbers are about average for this 



time of year. 



We repeat from our June 11, 1973 Bulletin: 



Horn flies , face flies , and stable flies are just beginning to appear on pastured cat- 

 tle. Begin your control program early before the number of these flies builds up. 

 They cause reductions in milk flow and beef production. 



For dairy cattle, apply crotoxyphos (Ciodrin) as a 1- to 2-percent, oil-base spray 

 ready-to-use. Use it at 1 to 2 ounces per animal two to four times a week, or as a 

 1-percent water-base spray at 1 pint per animal per week. As alternatives, you can 

 use oil-base sprays of 1-percent dichlorvos (DDVP) or a 0.1-percent pyrethrin spray 

 applied at 1 to 2 ounces per animal per day can be used. Pay particular attention to 

 the animal's legs and undersides when spraying. 



Ciodrin is the most effective insecticide for controlling face flies . All of the 

 above insecticides provide good control of horn flies and fair control of stable 

 flies. Dust bags containing insecticides like coumaphos (Co-Ral) or crotoxyphos 

 (Ciodrin) effectively control horn flies, but not face flies and stable flies. 



For beef cattle, apply a water-base spray of 0.5-percent toxaphene at the rate of 1 

 to 2 quarts per animal every three weeks. Toxaphene provides excellent control of 

 horn flies, fair control of stable flies, and poor control of face flies. If face 

 flies become a serious problem, use crotoxyphos (Ciodrin) as suggested for dairy cat- 

 tle. A canvas or burlap head-oiler or back-oiler, saturated with a solution of 5- 

 percent toxaphene in oil, will provide some relief against face flies. Do not apply 

 toxaphene to beef cattle within 28 days of slaughter. 



HOMEOWNER INSECT PROBLEMS 



Bagworm larvae can be found inside the small "tents" they are building. In about four 

 to six weeks, they will be full-grown and all their damage will have been done. Some 

 people who spray then will wonder why the bags do not disappear or why the worms are 

 not killed. Once they become full-grown, sprays seldom kill them. If you wait until 

 then, do not spray. Begin a campaign of picking off the bags. Put them in a sack, 

 coffee tin, or similar container and place them in the garbage can. This will min- 

 imize the number you will have to combat in 1974, since they winter as the egg stage 

 in these bags. 



Now, not later, is the time to spray for this year's crop of bagworms . Use sprays 

 of carbaryl (Sevin) , diazinon, malathion, or Bacillus thuringiensis (Dipel, Biotrol, 

 Thuricide) . Do not use malathion on canaert red cedar. Do not use diazinon on ferns i 

 or hibiscus. Follow the directions on the label. 



