P.n 7 



COLLEGE OF 

 AGRICULTURE 

 UNIVERSITY OF 

 ILLINOIS AT 

 URBANA-CHAMPAIGN 

 AND NATURAL 

 HISTORY SURVEY 

 URBANA, ILLINOIS 



NSECT WEED & PLANT DISEASE SURVEY BULLETIN 



rATE/COUNTV/LOCAL GROUPS/U.S. DEPARTMENT OF AGRICULTURE COOPERATING 



FOR IMMEDIATE RELEASE 



No. 2, March 30, 1973 



This series of weekly bulletins provides a general look at the insect, weed, and 

 plant disease situation (fruit and commercial vegetables excepted), along with sug- 

 gested, abbreviated, control measures. Each individual should check his own fields 

 to determine local conditions. 



INSECTS •%<-, 



FORAGE INSECTS Qe- ^ 



Alfalfa weevil are continuing to deposit eggs in alfalfa; fields lif southern Illi- 

 nois!! Some small green larvae are present in terminal growth, but' no high popu- 

 lations have been found as yet. Warmer weather will accelerate the hatch of these 

 eggs, and we may see an increase in larval populations soon. No larvae have been 

 observed in central Illinois. 



If 50 percent of the terminals now have alfalfa weevil feeding, using an insecti- 

 cide is justified. But you can still delay application a few days to allow more 

 eggs to hatch. 



The insecticide recommendations are: 



1. Commercial applicators . Apply 1/2 pound per acre of methyl parathion, azin- 

 phosmethyl (Guthion) , or Supracide--or 1/4 pound of carbofuran (Furadan) . Use 

 azinphosmethyl only once per cutting, and do not harvest for 16 days. Do not 

 harvest for 15 days after a treatment with methyl parathion, 7 days after 

 using 1/4 pound of carbofuran, or 10 days after using 1/2 pound of Supracide. 

 As a general precaution, wear protective clothing. Higher dosages of carbo- 

 furan will require longer waiting periods. 



2. Persons not equipped with protective clothing . Use: (1) Imidan at 1 pound 

 per acre; (2 ) a mixture of 3/4 pound of malathion and 3/4 pound of methoxy- 

 chlor per acre; (3) a mixture containing at least 1/2 pound of diazinon and 

 1 pound of methoxychlor (Alfa-Tox) per acre; or (4) 1-1/4 pounds of malathion 

 per acre on days when air temperatures will be about 60° F. for several hours 

 after application. Do not harvest for 7 days after treatment with Imidan, 

 methoxychlor, diazinon, or mixtures of them. There is no waiting period for 

 malathion. Do not apply Imidan more than once per cutting. 



The following comments are similar to those made in 1972: 



Alfalfa and clover hay crops may serve as a breeding area for beneficial insects, 

 such as lady beetles, aphid lions, and wasp parasites, that attack many species of 

 aphids. When hay is cut, they move to other fields. Therefore, do not use insec- 

 ticides in alfalfa or clover fields unless it is necessary to save the crop and un- 

 less you use all the hay you can produce. If there is a choice, harvest early. 



