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To decide whether to apply an insecticide, count the egg masses on several 

 plants in several locations in the field. Observe each leaf closely. If the average 

 is one or more egg masses per plant, treatment may be profitable. Use 1 1/2 pounds 

 of carbaryl (Sevin) or 1 pound of diazinon per acre as granules, applied by air or 

 ground equipment. They will be equally effective. Sprays applied by ground machines 

 will be as effective as granules against corn borer, but sprays applied by airplane 

 will be less effective. 



True armyworms are feeding on corn leaves and in some cases on the silks in 

 some grassy cornfields. In general, the worms are about full grown or have already 

 pupated and feeding damage should soon lessen. It is too late for control in most 

 cases. Carbaryl at 1 pound per acre will control armyworms if needed. 



Simyra henrici , the cattail caterpillar , which is orange and brown, is common 

 in cornfields throughout the state. These insects eat the leaves of corn, but they 

 have never been serious enough to justify control. 



Two-spotted mites are still damaging soybeans. The mites appear as small 

 black spots on the undersides of the leaves. The problem is most acute in areas 

 where soil moisture remains low. Affected soybeans show stunting, yellowing and 

 browning of leaves, but the infestation is usually spotty within a field. If a field 

 is severely affected, the mites can be controlled by applying 3 A pound of carbopheno- 

 thion (Trithion) per acre. This insecticide is highly toxic and should be applied 

 only by experienced operators . Allow 7 days to elapse between treatment and harvest. 



Alfalfa webworms and some green clover worms are feeding on the leaves of 

 soybeans. In the central section, however, most of the worms have matured and are 

 already emerging as moths. You can see these small buff-colored moths flying from 

 the plants as you walk the rows. The moths may continue to lay eggs in the same 

 field or scatter them in adjacent fields of soybeans or alfalfa. In another week or 

 two it may pay to check soybean fields again for this insect. Webworms can be readily 

 controlled in soybeans by applying 1 1/2 pounds of toxaphene per acre. In alfalfa, 

 use 1 pound of carbaryl per acre to control webworm and other leaf-feeding cater- 

 pillars. Carbaryl can be used on soybeans, but it may contribute to mite buildup. 



Face flies and stable flies are increasing on pastured cattle. Some indi- 

 vidual herds are averaging 10 to 20 of each of these flies per animal, and the cattle 

 are being noticeably bothered. Horn flies are also present in moderate numbers. 



For pastured dairy cattle, apply 1 or 2 ounces of an oil-base spray of 

 2 percent ciodrin per animal every two to three days for best results against the 

 pasture fly complex. A 1.0 percent dichlorvos (DDVP) or 0.1 percent pyrethrin oil- 

 base spray applied at the rate or 1 or 2 ounces per animal per day does not give as 

 effective control as ciodrin, particularly against the face fly. Water-base sprays 

 of the same material may be used, but control is less effective. Pay particular 

 attention to the animal's legs and undersides when spraying. 



For pastured beef cattle, head oilers or backrubbers made of cloth, burlap 

 Dr canvas and saturated with 5.0 percent toxaphene in oil are partly effective in 

 suppressing face flies. However, for stable and horn flies, a water-base spray of 

 D.5 percent toxaphene, applied at the rate of 1 or 2 quarts per animal every three 

 ^eeks, may be needed. Allow 28 days to elapse between treatment with toxaphene and 

 .slaughter. A 2.0 percent ciodrin oil-base spray, applied at the rate of 1 or 2 ounces 

 per animal every two to three days from an automatic sprayer, is an excellent way to 

 control flies on pastured beef cattle if the situation permits its use. 



