-2- 



2 - Malathion,! pound per acre . It is effective for approximately 3 to 7 days. 

 Do not apply if air temperatures are below 60° F., since failure may result. 

 There is no waiting period between treatment and harvest, which makes it an 

 ideal choice for pasture treatment. 



3. Methoxychlor, 1 pound per acre . It is effective for approximately 5 to 8 days. 

 Do not harvest for 7 days after treatment. Results from Dr. Ed Armbrust's re- 

 search plots show methoxychlor to be less effective than malathion or Alfatox. 



4. Methyl parathion, 1/2 pound per acre . FOR USE ONLY BY EXPERIENCED APPLICATORS. 

 It is effective for approximately 8 to 12 days. It is already too late to use 

 this material on fields which are to be harvested within 15 days. 



5. Azinphosmethyl (Guthion) , 1/2 pound per acre . FOR USE ONLY BY EXPERIENCED AP- 

 PLICATORS. It is effective for approximately 10 to 14 days. Do not apply more 

 than once per cutting. It is already too late to use this material on fields 

 which are to be harvested within 16 days. Water temperature for the spray mix 

 should be above 55° F. 



Carbaryl (Sevin) recently received new label registration for use against alfalfa 

 weevil larvae. Field trials in Illinois showed carbaryl to be less effective than 

 the insecticides now recommended. 



Pea aphids are very abundant in many alfalfa and clover fields and some curling 

 and yellowing was observed. The cool weather aids aphid development and retards 

 plant growth. Therefore, if plants begin to show wilting, spray with 1 pound of 

 actual malathion per acre. 



Small clover leaf weevil larvae are still present in clover and alfalfa fields in 

 western and northern sections . Feeding was noticeable, but not of concern. If 

 weevil feeding begins to get ahead of plant growth, a spray of 1 pound per acre 

 of malathion is effective. 



Small Grain Insects 



English grain aphid populations on wheat have declined and this threat appears to 

 be over. Howe\ r er, plant pathologists have identified wheat streak mosaic disease 

 in southern Illinois and yellow dwarf on -wheat in central and western Illinois. 

 Wheat streak mosaic disease is transmitted by the wheat curl mite and yellow dwarf 

 by aphids. These insects cannot be controlled well enough to prevent spread of the 

 disease , 



A cereal leaf beetle preventive spray program is underway in two counties. Approxi- 

 mately 30,000 acres in Vermilion Comity and 40,000 acres in Will County are being 

 treated by air with 4 fluid ounces of technical malathion (9.7 pounds per gallon) 

 per acre. These areas were treated last July (1966), when a few specimens were 

 found following the 1966 spring treatment. This year's treatment will provide 

 further insurance that the beetle has been eradicated from Illinois for the pres- 

 ent. 



Corn Insects 



Flea beetles were observed damaging small corn in the southern sections. The mild 

 winter should have permitted good survival of flea beetles. Newly emerging corn 

 should be watched for the presence of small, shiny, black beetles that jump readily 



