

40 



azinphosmethy.l insecticide to control fall populations of the boll weevil, 

 Anthonomus grand is Boheman. The eight-county control zone contained approxi- 

 mately 60 percent fewer acres infested with weevils in 1967 than in 1964. The 

 potential overwintering weevil population in the control zone in 1967 was esti- 

 mated to be 85.6 percent smaller than in nearby untreated fields. An estimated 

 eight weevils per acre were found in April 1968 in hibernation sites near 

 treated fields. That compared to 484 weevils per acre in sites near untreated 

 fields. 



70. , and Almand, L. K. 1969. The effects of reproductive-diapause boll 

 weevil control programs on populations of the bollworm and the tobacco 

 budworm in cotton, 1968. Tex. Agric. Exp. Stn. Prog. Rep. PR-2702; pp. 

 1-6. 



In the spring and summer of 1968, larval populations of the bollworm, Heliothts 

 zea (Boddie) , and tobacco budworm, Heliothis virescens (F.), were about equal in 

 size in cotton fields which were sprayed with malathion insecticide for boll 

 weevils, Anthonomus grandis Boheman, in the fall of 1967 and in fields not 

 sprayed in 1967. But in the fall of 1968, after cotton had received several 

 aerial applications of either ultra-low-volume (ULV) malathion or azinphosmethyl 

 (Guthion®) , more bollworms and tobacco budworms were present in treated fields 

 than in ^heck fields. The fall bollworm-budworm populations in treated fields 

 apparently increased after the insecticide treatments killed many beneficial 

 insects which held the pests in check in untreated fields. 



71. , and Almand, L. K. 1970. Evaluation of the 1968 reproductive- 

 diapause boll weevil control program of the Texas High Plains. Tex. 

 Agric. Exp. Stn. Prog. Rep. PR-2766, 15 pp. 



Beginning September 3, a total of 616,629 acres of cotton was sprayed by 

 aircraft under the supervision of the Plant Protection Oivision, Agricul- 



<U)M« 



