CORN INSECTS 



White grubs . They were reported feeding on the roots of early corn in Sangamon 

 County this week. Populations ranged from 2 to 25 per yard of row, with an 

 average of 12. There are many species of white grubs. They usually have a three- 

 year life cycle. 



The grubs in the Sangamon County field were a different species than the ones that 

 caused a problem in soybeans in 1965 and again in 1968. After the corn is up, con- 

 trolling this grub is difficult. An application of aldrin or heptachlor using a 

 rotary hoe and followed by an inch of rain will help. There is no control avail- 

 able for soybeans. We have no information on the newer insecticides as a control 

 for this pest. 



Leafhoppers . They are now prevalent on corn, particularly along grass -sod areas 

 such as waterways in southern Illinois. Ordinarily, this pest does not seriously 

 damage the corn, which means that chemical control would not be profitable. 



Corn flea beetles . These are very numerous in corn fields in the central and 

 southern sections of the state. There is an average of 6 to 10 beetles per plant 

 in some stands of corn. The tiny, shiny black, corn flea beetles --which jump when 

 disturbed- -feed on the surface of the corn leaf, leaving scratch marks and often 

 causing the leaves to turn white or silvery. The plants are sometimes killed. 



If these beetles are numerous and damage is severe, apply 3/4 pound of carbaryl 

 (Sevin) --preferred on dairy farms- -or 1-1/2 pounds of toxaphene per acre as a band 

 spray over the row. The grassy areas in and around the field, such as waterways 

 and fence rows , should also be treated to prevent additional beetles from moving 

 into the field. Do not use carbaryl near bee hives or toxaphene near fish-bearing 

 waters . 



Insect reports this week were received from Denver Corn, Sangamon County Extension 

 Adviser; Robert Frank, Jackson County Extension Adviser; and Robert Schmerbauch, 

 Wayne County Extension Adviser. 



HOMEOWNER INSECTS 



Eastern tent caterpillars . They have severely defoliated trees in some areas of 

 southern Illinois. These dark-colored worms with a white stripe down the back 

 spin their webs in the crotches and on the limbs and trunks of trees , especially 

 wild cherry. Many caterpillars are now full grown (2 inches long) , and are 

 spinning cocoons- -on the tree or some nearby structure. 



If most of the Eastern tent caterpillars are less than 1-1/2 inches long, they 

 can be controlled with carbaryl (Sevin) or malathion, applied as a spray. Do 

 not treat if larvae are full-grown or are pupating. 



Oystershell scale . These eggs are beginning to hatch in southern and central sec- 

 tions of Illinois. Another two weeks will be required to complete the hatch. These 

 brownish-gray scales, about 1/8 inch long, are often found on lilacs, dogwoods, 

 birches, and soft maples, as well as other shrubs and trees. The newly hatched 

 crawlers move to new areas on the bark and set up housekeeping by constructing a 

 scale over their body. 



