-2- 



2 pounds of methoxychlor and 2 pounds of malathion per gallon) , or a mixture 

 containing at least 1/2 pound of diazinon and 1 pound of methoxychlor per acre 

 (2 1/2 to 3 quarts of the commercially prepared mixture Alfatox) . You may 

 also use 1 1/4 pounds of malathion per acre (1 quart of the 5-pounds-per-gallon 

 concentrate) in the morning on days when air temperatures will be above 60° F. 

 Do not harvest for 7 days after treatment with methoxychlor, diazinon, or mix- 

 tures of them. There is no waiting period for malathion. 



The quantity of finished spray applied per acre is also important. Use no less than 

 4 gallons per acre by air or 20 gallons per acre by ground machine. The exception 

 is on stubble, where 10 gallons per acre by ground will be sufficient. 



Pea aphids are abnormally low this year in alfalfa and clover fields. 



Spittlebugs are more numerous this year. Froth masses are easily found in clover 

 and alfalfa fields in the south central part of the state, ranging from 1 mass per 

 10 to 20 stems. In northern Illinois, nymphs averaging 1 per 4 stems are down low 

 in the leaf sheath but will soon move higher on the stems and froth masses will 

 appear within the next 1 to 2 weeks. Damage so far is light. 



Chemical control is usually not profitable if spittlebug nymphs average fewer than 



1 per stem. If treatment is necessary, use 3/4 pound of methoxychlor per acre. 



Corn Insects 



Seed corn beetles have been reported causing damage to an occasional field in cen- 

 tral and northern areas. The seed corn beetles (about 1/4 inch long) are brown 

 with a light tan border on their wing covers or a uniform chestnut brown. The 

 beetles hollow out the seed, resulting in poor germination and reduced stands. 

 If replanting is necessary, apply diazinon or phorate (Thimet) as a 7- inch band 

 on the soil immediately ahead of the press wheel. 



Black cutworm moths have been flying for several weeks, but there has been no 

 damage reported from newly hatched larvae. Watch for damage in low, poorly drained 

 areas of a field, especially where a soil insecticide was not applied. Broadcast 

 applications of aldrin or heptachlor at or before planting have given good protec- 

 tion against this pest. If damage appears, treat with either carbaryl (Sevin) at 



2 to 3 pounds actual ingredient per acre, or diazinon at 2 pounds, or toxaphene at 



3 pounds per acre, or trichlorfon (Dylox) at 1 pound per acre. Results will be 

 improved if the spray is directed at the base of the plants, if at least 20 gallons 

 of finished spray is used per acre, and if the spray is incorporated with a culti- 

 vation immediately after application. 



Corn flea beetles are not yet a problem, but periodic checks of newly emerging corn 

 should be made for their presence. The adults are small, smooth, black, shiny, and 

 roundish, and jump readily when approached. They inflict white scratch marks on 

 the first three or four true leaves and may cause the seedling to appear whitish 

 or silvery and sometimes kill the plant. If damage is severe and plants are being 

 killed, apply 5/4 pound of carbaryl (Sevin), or 1 1/2 pounds of toxaphene per acre 

 as a band spray over the row 



Corn borer pupation reached 70 percent in extreme southern sections this week. 

 Moth emergence should begin next week. Pupation is just beginning in central 

 sections. 



