three days. There is no waiting period between the application of toxaphene and 

 grain harvest; a week is required when applying malathion, 21 days for trichlorfon. 



Sawflies. 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 were found in many wheat fields this week. They do not 

 damage wheat plants enough to require control. 



CORN INSECTS 



Armyworms . This pest is also present in thick stands of grasses along roadsides, 

 in pastures, and in some hay fields. They are larger than tnose found in small 

 grain fields. These worms may soon migrate to adjacent fields with crops such 

 as corn. When this happens, damage can be severe. In some cases the armyworms 

 merely eat the leaves and the plant continues to grow; in others, they eat the 

 plant down into the ground. 



Occasionally, armyworms are a serious problem in corn planted on grass sods or when 

 rye has been plowed under in the spring. Before plowing, the moths deposit -eggs in 

 the grass. Afterward, eggs hatch and the tiny worms feed on the grass. They soon 

 move to the surface, where they will devour the small corn seedlings. 



Also watch fields in which no- till corn has been planted on grass sods. Armyworm 

 moths deposit eggs in the grasses. The worms move up readily into the small corn. 



The insecticides for wheat can also be used on corn to control armyworms . 



Black cutworms . A few reports were received from western Illinois this week. Corn 

 that is is cut off above the growing point will usually recuperate, but plants 

 that are cut off below the growing point or heart are killed. In evaluating dam- 

 age, take this possible regrowth factor into consideration before disking-up a 

 field for replanting. 



However, as soon as you see cutworm damage, apply control measures. Control is 

 much easier when the worms are small. 



You can control cutworms with an application of a carbaryl (Sevin) bait. A bait 

 of 5-percent carbaryl on apple pomace applied broadcast at 20 pounds per acre is 

 effective. A liquid bait, using molasses or Tractum with carbaryl, applied as a 

 spray directed at the base of plants (1 pound per acre) or broadcast (2 pounds 

 per acre) is also effective. Do not cultivate when a carbaryl spray or a granular 

 bait is applied . Trichlorfon (Dylox) applied at 1 pound per acre in at least 20 

 gallons of water as a spray directed at the base of the plant will also provide 

 control. Cover the trichlorfon spray band by throwing the soil at the base of t 

 the plants with a cultivator. Do not use sugar baits near bee hives. 



Yellow- striped armyworms . These dark- colored worms with yellow or white stripes 

 on each side of the back are feeding on corn leaves. This feeding is usually of 

 no consequence, so no not apply chemical control unless you feel that the popu- 

 lation of worms is extremely high. 



Wireworms . Several fields of com were damaged by this pest this week. If re- 

 planting is necessary, use one of the phosphate insecticides (diazinon at 2 pounds 

 per acre or Dasanit, Dyfonate, or Thimet at 1 pound per acre) as granules in a 

 7-inch band just ahead of the press wheel. These insecticides will control the 

 small wireworms, but may not control the larger ones. 



