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FOB IMMEDIATE RELEASE April 27, 1962 



INSECT SURVEY BULLETIN NO. 2 



This is the second in a series of weekly bulletins on the general insect 

 situation in Illinois (fruit insects excepted), prepared by entomologists of the 

 University of Illinois College of Agriculture, Illinois Natural History Survey and 

 cooperating agencies. It is designed to forewarn people in Illinois of impending 

 changes in insect activity and to suggest abbreviated control measures. These re- 

 ports indicate only general trends. Each individual should check his own fields 

 to determine local conditions. 



Clover leaf weevil populations are not generally high, but occasional 

 fields of clover are showing some damage. Most of these green worms are about one- 

 third to one-half grown and can be found under trash on the ground; some very small 

 ones may be hiding in the crown of the plant or behind leaf sheaths. These insects 

 feed at night. Examine slow-growing clover fields, particularly those with heavy 

 trash cover in the . northern -half of the state. Such fields may have some damage, 

 but there is an excellent chance that warm weather will enable the plants to out- 

 grow most of it. For insecticide treatment, refer to spittle bugs. 



Spittle bug hatch began this week and will continue for the next week or 

 two. Populations will be highest in the northern third of the state. Only fields 

 with an average of one spittle bug nymph or more per stem will warrant treatment. 



If control measures are needed for clover leaf weevil and spittle bugs, 

 make applications within the next week or ten days for best results. Apply 1 pound 

 of methoxychlor or one -fourth pound of lindane. Allow one week to elapse between 

 application of methoxychlor and harvest of hay or use as pasture, and 28 days with 

 lindane . 



Pea aphid populations are not yet very high. Lady beetles feed on aphids, 

 and tiny wasps also parasitize them. A fungus disease, most prevalent during warm, 

 humid weather, also kills many aphids. Warm, wet weather favors rapid increase of 

 these naturally occurring aphid enemies. 



If we have either cool or warm, dry weather, these aphids could become 

 abundant during the next three weeks. Buildup may occur on alfalfa within the next 

 week to ten days in southern Illinois, and about a week later in the north. 



Insecticide applications, when necessary, should be made before severe 

 wilting and discoloration of plants. Use 1 pound of malathion, l/k pound of para- 

 thion or phosdrin or 1/8 pound of demeton per acre. Allow one week between treat- 

 ment and harvest when using malathion, 1 day with phosdrin, 15 days with parathion, 

 and 21 days with demeton. Only one application of demeton can be made per cutting. 

 Demeton, parathion, and phosdrin should be applied only by an applicator experienced 

 in handling toxic organic phosphates. 



Face flies are generally present in small numbers on herds of cattle 

 throughout the northern three-fourths of Illinois. Female flies are laying eggs that 

 will produce the first buildup of flies for the summer months. Dairymen should be- 

 gin baiting programs immediately, brushing DDVP in corn sirup on the foreheads of 

 cattle. Beef producers having cattle on pasture should keep backrubbers well satu- 

 rated with 5$ toxaphene in oil. Allow 30 days to elapse between application of 

 toxaphene on beef cattle and slaughter. Toxaphene cannot be used on dairy cattle. 



