insects and yields of seed cotton were obtained 

 with the same amount of active ingredients 

 applied with an air-carrier sprayer at the rate 

 of 30 gallons of spray material per acre as with 

 a conventional boom-type sprayer at 6 gallons 

 of spray material per acre. 



188. Wilkes, L. H., and others. Spray noz- 

 zle arrangements, types and rates of applica- 

 tion for cotton insect control. Tex. Agr. Expt. 

 Sta. Misc. Pub. 595, 12 pp. 1962. 



P. L. Adkisson, B. J. Cochran, and R. L. 

 Hanna, joint authors. 



Research has been conducted for the past 

 several years on the effects of nozzle types and 

 arrangements and of application rates of con- 

 centrated spray materials on cotton-insect con- 

 trol. The effectiveness of the variables studied 

 has been based on field insect infestations and 

 the yields of cotton. Effective control of boll 

 weevils and bollworms can be maintained with 

 low rates of total spray material applied with 

 simple nozzle arrangements. Complicated noz- 

 zle arrangements for applying high rates of 

 spray material per acre are not necessary to 

 obtain effective cotton-insect control. In these 

 studies a nozzle arrangement with only one 

 nozzle per row was equally effective for control- 

 ling insects as an arrangement with up to three 

 nozzles ner row. provided the same amount of 

 active insecticide and total spray was applied. 

 Equally effective control of cotton insects was 

 obtained with an application rate of 2 gallons 

 per acre as compared with 6 and 14 gallons per 

 acre if the same amount of insecticide per acre 

 was used with each rate. The three types of 

 boomless nozzles evaluated did not prove satis- 

 factory for the application of insecticides in 

 cotton. 



189. Wilkes, L. H., Cochran, B. J., and 

 Adkisson, P. L. Further studies of the effec- 



tiveness of certain spray nozzle types and sizes 

 and arrangements for controlling boll weevils 

 and bollworms. Tex. Agr. Expt. Sta. Prog. 

 Rpt. 2264, 5 pp. 1963. 



A variety of spray nozzle types and orifice 

 sizes will produce effective control of the boll 

 weevil and bollworm provided adequate amounts 

 of insecticide are applied at opportune times. 

 Results of this study showed no significant dif- 

 ferences in insect control or yields produced in 

 plots sprayed with nozzles ranging from size 

 X3 to X18. Sprayed plots showed increased 

 yields of approximately 1,000 to 1,100 pounds 

 of seed cotton over the unsprayed check. 



190. Wilkes, L. H., and Walker, J. K., Jr. 

 Modification of a commercial high-clearance 

 sprayer for use in small plot spraying. Jour. 

 Eeon. Ent. 54: 601-603. 1961. 



Development of low-gallonage sprays for 

 control of cotton insects created a need for 

 suitable sprayers for researchers. Diagrams for 

 modifications of the spraying system of com- 

 mercial sprayers are given. 



191. Wolfenbarger, D. A. Insecticides and 

 insecticide-oil combinations for corn earworm, 

 boll weevil, and cowpea curculio control. Fla. 

 Ent. 48: 101-109. 1965. 



Paraffinic oil-DDT plus toxaphene combina- 

 tion at IV2 an d 3 gallons per acre gave better 

 control of the boll weevil than DDT plus toxa- 

 phene alone, any of the other treatments, and 

 the check. The rate of oil in the insecticide-oil 

 combination did not increase insect control. All 

 aerosol-applied insecticide and insecticide-oil 

 combination applications gave better boll wee- 

 vil control than the oil-insecticide-water com- 

 bination applications. The oil-insecticide-water 

 combinations or insecticide combinations were 

 ineffective in controlling the boll weevil. Data 

 for the other two insects are given. 



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