Small-Grain Insects 



True armyworms can still be found in luxuriant stands of small grains and grasses 

 south of Highway 40; such fields should continue to be observed. The worms are . 

 still small, and it may be 10 days to 2 weeks before any damage appears. No 

 serious infestations have been reported as yet. 



Sawflies , which are yellow- to-green, transparent, velvety worms, are also present 

 in wheat fields, but they do no damage. These worms are not striped, as are the 

 true armyworms. Furthermore, they have fleshy prolegs on every segment of the 

 back half of their body, which they use for walking and grasping the surface of 

 a stem securely. True armyworms have only 4 pairs of such prolegs. 



English grain aphids have appeared in numbers in a very few fields of small grains 

 in western and southwestern Illinois. They may increase with continued cool 

 weather . 



Cereal leaf beetle detection surveys are now or soon will be conducted in the 

 northern two- thirds of the state. Representatives of the state and federal govern- 

 ment will be examining small-grain fields, particularly oats, for this new foreign 

 pest. A few specimens have been found in Illinois during the past two years. 

 These scouts will contact your University of Illinois county Extension adviser be- 

 fore the survey begins. 



Corn Insects 



Corn seed beetles are abundant in some fields. Damage is reported from fields 

 treated with aldrin or heptachlor, indicating resistance. Under adverse conditions 

 for germination, damage will be more serious than when conditions favor rapid 

 germination. 



Most damage occurs in end rows and for a short distance into full-size field rows. 

 The entire field is not usually affected. Furthermore, some seeds in dry soil 

 or that were planted too deep have not germinated; do not confuse this lack of 

 germination with beetle injury. Examine kernels for beetle injury- -if there is 

 none, the seeds may still germinate. Furthermore, do not disk-up a reasonably 

 good stand- -it might still produce more corn than a later planting. 



When replanting, you may need one of the insecticides used for corn rootworm con- 

 trol, applied as a band on the soil surface ahead of the press wheel. We suggest 

 1 pound of diazinon per acre, but other rootworm insecticides may also give con- 

 trol. When replanting, consider the conditions; if they favor rapid germination, 

 treatment may not be necessary. 



Wireworms have damaged a few fields of corn already. No insecticide had been 

 used. Although it is difficult to control these pests after corn is planted, a 

 spray of aldrin or heptachlor may greatly retard further damage. Apply 1 pound 

 of the actual chemical per acre; direct the spray at the base of the plant. Cul- 

 tivate immediately, then hope for about an inch of rain to help carry the insec- 

 ticide down to the wireworms. Do not use aldrin or heptachlor on dairy farms; 

 try diazinon. 



Black cutworms may soon appear. Watch low spots in cornfields. When the first 

 plants are cut, get ready to apply an insecticide while the worms are still small 

 and can be controlled. Applications of 3 pounds of toxaphene, 2 to 5 pounds of 



