LIGHT TRAPS TO PREDICT NEED FOR CONTROL 



[SUMMARY] 



T. R. Pfrimmer l 



Research work with light traps, as reported in the published literature, has been con- 

 cerned primarily with: 



1. The evaluation of light sources and/or trap designs for attracting and catching 

 insects. 



2. The determination of species, sex, seasonal occurrence, and other phases of the 

 biology of insects collected by means of light traps. 



3. The evaluation of light traps as a direct means of controlling or preventing in- 

 jurious infestations of certain species of insects. 



Very few published references were found which could be said to pertain directly 

 to my subject. Some information has been gathered through correspondence and talks with 

 various workers in this field. 



Merkl and Pfrimmer (1955) ? reported a high degree of correlation between the num- 

 bers of bollworm moths caught in light traps at Stoneville, Miss., and Tallulah, La., and 

 the numbers of bollworm eggs per 100 terminals found in cottonfields in each area during 

 the summer months of 1954. Although the data are not presented in their paper, Merkl 

 and Pfrimmer also attempted to correlate the light-trap catches of bollworm moths with 

 the number of bollworm larvae found per 100 terminals and the percent of bollworm- 

 injured squares for each area. The correlations were not great enough to be significant. 

 It is believed this was due at least in part to the intensive insecticidal control program 

 being carried out in both areas against the boll weevil and other cotton insects. 



Huffaker and Back (1943) stated: "For more than a decade the New Jersey mosquito 

 trap has been used as a practical and very popular device for gaining information for use 

 in the planning and operation of mosquito abatement programs in the Atlantic Coastal 

 states. The development of this means of sampling mosquito populations must rank with 

 the major recent accomplishments in the mosquito control field." 



Marshall and Hienton (1938) said: "It has been suggested to apple producers that one 

 or more light traps in the orchard around the packinghouse, or other farm buildings 

 where apples have been stored, is an excellent means by which the daily flight activities 

 of this insect (the codling moth) may be determined as an aid in the timing of sprays, 

 thinning the fruit and timing other orchard operations which are determined by moth 

 flight." 



According to Howard Deay and J. H. Paullus, in Indiana and Illinois, light-trap 

 data are used in timing the beginning and end of insecticidal applications for the European 

 corn borer and the corn earworm. In Wisconsin recommendations for the control of corn 

 earworms in canning sweet corn are timed by light-trap catches. 



Light-trap collections have been used for the past 5 years to predict when insecticidal 

 applications are needed for controlling the tomato fruitworm in Indiana. Timing of the 

 first treatments for codling moth control in Wisconsin in 1959 was determined from 

 light-trap catches. 



i Entomologist, Entomology Research Division, Agricultural Research Service, U. S. D. A., Stoneville, Miss. 

 2 For references in this paper, see section on Bibliography of Insects and Light at end of this publication. 



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