1957 - Lincoln, C. and T. F. Leigh. Tinning insecticide applications for cotton insect 

 control. Ark. Agr. Expt. Sta. B. 588. May. 



Ten years of research work relating to timing of applications of insecticides 

 to cotton. Applications of insecticides for boll weevil control greatly increased 

 yields of cotton when infestations were heavy and conditions favorable for fruiting 

 of cotton plants. When infestations are low or conditions unfavorable for fruiting, 

 applications of insecticides do not increase yields of cotton. In general, using 

 insecticides in such a manner as to maintain a seasonal average infestation of 

 40% punctured squares maintained yields and cost less than more frequent appli- 

 cations. 



Irrigation creates favorable conditions for the boll weevil and increases 

 fruiting and potential yield of the cotton. Boll weevil control may be quite 

 profitable on irrigated cotton when it would not pay on nonirrigated cotton. 



1957 - McGarr, R. L. Tests with Insecticides for control of cotton insects in the Lower 

 Rio Grande Valley. J. Econ. Ent. 50(5):632-634. 



TESTS IN 1948. --Treatments satisfactorily reduced the boll weevil popula- 

 tions. The greatest reduction was induced by chlordane plus sulfur. The best 

 increase in yield was obtained from the treatment of calcium arsenate plus sulfur, 

 this being closely followed by all the other treatments except the chlordane plus 

 sulfur which seemed to have an adverse effect on the plants. 



Treatments with calcium arsenate, alone and in combination with sulfur and 

 parathion, gave about equally effective control of weevils and practically the same 

 substantial increases in yield. Although BHC plus DDT and sulfur, and BHC plus 

 methoxychlor and sulfur gave only fair reductions in boll weevils, the former was 

 superior in yield due to control of a bollworm infestation. 



TESTS IN 1950.--Dieldrin dust and spray gave good control of the boll 

 weevil infestations, whereas reductions for toxaphene plus sulfur and calcium 

 arsenate plus sulfur were noticeably lower. Toxaphene was included in a spray 

 at 3 lbs. per acre, but it failed to give satisfactory results after 3 applications, 

 and its use was discontinued. The dieldrin spray was the only spray used 

 throughout the season. It gave good control of the boll weevil, but the plants did 

 not seem to fruit as well as where the dieldrin- sulfur dust was used. 



In a second series, treatments of low-lime calcium arsenate plus parathion 

 and BHC, heptachlor plus sulfur, aldrin plus sulfur, and calcium arsenate plus 

 sulfur, all substantially reduced boll weevils. The heptachlor- sulfur effected the 

 greatest weevil reduction, and calcium arsenate- sulfur, the least. 



TESTS IN 1952. --In a spray series with Metacide, methyl parathion, 

 heptachlor, endrin, and dieldrin, endrin gave very good control of both the boll 

 weevil and the bollworm, followed closely by dieldrin. Methyl parathion gave 

 only fair control of the boll weevil under heavy infestations late in the season. 

 Metacide was not quite so good as methyl parathion, and heptachlor was the 

 poorest of all the materials. 



TESTS IN 1953. --In one dust series the best reduction of boll weevils was 

 obtained with low- lime calcium arsenate containing 1% methyl parathion. All 

 the other treatments, 2.5% heptachlor plus sulfur, 5% heptachlor plus sulfur, 

 methyl parathion plus DDT, and dieldrin plus sulfur gave satisfactory control, 

 except the 2.5% heptachlor'and sulfur, where the control was only fair. The 

 greatest yield was from the methyl parathion plus DDT, followed by the low-lime 

 calsium arsenate plus methyl parathion and the dieldrin plus sulfur. 



TESTS IN 1954. --Dust treatments of low-lime calcium arsenate plus methyl 

 parathion, endrin, dieldrin plus methyl parathion and DDT, and dieldrin plus 

 sulfur, all gave satisfactory control of the boll weevil under moderate infestations. 



The best increase in yield was from the dieldrin- methyl parathion- DDT 

 mixture, and the next from endrin. It is doubtful, though, if the 1.5% endrin treat- 

 ment would be satisfactory against heavy infestations of the boll weevil. 



1957 - McGarr, R. L. Insecticides for pink bollworm and boll weevil control in the 

 Lower Rio Grande Valley in 1955 and 1956. J. Econ. Ent. 50(5):672-674. 



TESTS IN 1955. --Series 1. Treatments of Guthion plus DDT and endrin plus 

 DDT sprays noticeably reduced the boll weevil infestations and produced fair 



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