HOMEOWNER INSECTS 



Leafhoppers and plant bugs are damaging locust trees. Both insects have caused leaf- 

 lets - tosKow a mottled yellow appearance and to curl. Where infestations are severe, the 

 leaflets have turned brown. These leafhoppers are small, green, wedge-shaped insects. 

 Adult leafhoppers fly like a swarm of small gnats when a branch is disturbed. Plant 

 bugs are also green but are larger. Populations of plant bugs are declining; however, 

 there are still many young leafhoppers on honey locust trees. If the damage is severe 

 and insects are still present, treat the tree with malathion or carbaryl (Sevin) . 



The periodical cicada , or thirteen-year locust, has emerged in the central section and 

 in many areas of southern Illinois. The adults are swarming in and around wooded areas, 

 and leaving their pupal skins on the bases of trees and on fences, flower stems, and in 

 grass and weed areas. These locusts do not chew on leaves. Their only economic damage 

 is the result of egg-laying punctures in the twigs and small branches of trees. When 

 egg-laying begins, treat the infested trees with a spray containing carbaryl (Sevin). 

 Repeat five days later if necessary. 



Bagworms are hatching in southern Illinois, and will be hatching in the central section 

 by June 10. These tiny worms can defoliate evergreens such as junipers, as well as some 

 shade trees. As they feed, these worms construct a spindle-shaped bag in which they 

 live. In the southern section, sprays should be applied immediately. The target date 

 for spraying in the central area is after June 15; in the northern section, after June 

 30. Control bagworms while they are small and easy to kill. Once the bagworms become 

 half -grown or more, insecticide spraying often fails. 



For control, apply a spray containing carbaryl (Sevin), diazinon, malathion or Bacil- 

 lus thuringiensis (Biotrol, Dipel, Thuricide) . Follow the directions on the label. 

 Check carefully for plants that could be injured by the insecticides used. 



Striped cucumber beetles and occasionally spotted cucumber beetles are attacking the 

 young plants of such vine crops as cucumber, squash, and melons. These yellow and 

 black beetles feed on the leaves of seedling plants. Probably, the most serious 

 damage they do is to spread a bacterial wilt disease that can kill the plants. For 

 control, apply carbaryl (Sevin) as a dust or spray. 



SPECIAL NOTE TO EXTENSION ADVISERS AND PESTICIDE DEALERS 



The use of diazinon in dairy barns and milking parlors as a residual spray for flies 

 has been cancelled. Therefore, do not use diazinon this way. 



Diazinon can still be used to spray barns containing beef cattle, swine, poultry, and 

 sheep, as long as the animals are removed from the structure while it is being sprayed. 

 You may also wish to make a note of this change in UI Circular 898, Insect Control for 

 Livestock and Livestock Barns on page 3, where diazinon is suggested for use as a barn 

 spray. 



WEEDS 



POSTEMERGENCE CONTROL OF WEEDS IN CORN 



If com and weeds are still small enough, using a rotary hoe is an excellent way of 

 controlling postemergence weed problems. Good row cultivation works equally well. 



2,4-D can be a good follow-up herbicide, especially where a "grass-killer" has been 

 used for preemergence treatment. However, applying 2,4-D to corn that has been under 

 wet, cool stress conditions may increase the risk of injury. 



