409 



fall migratory period, a significant increase in the height of boll weevil 

 flight was recorded. Weevil capture at the 9.1 m level increased ca. 10-fold 

 in 1972 and 8-fold in 1973. Weevils were captured at altitudes up to 122 m 

 with aircraft-towed nets during the fall of 1973. During late season, migrating 

 weevils appeared to be distributed from near ground level up to relatively great 

 heights. These data indicate that considerable numbers of weevils may be capable 

 of the long-range movements reported from previous studies. 



801. ; Mclntyre, R. S.; and Neeb, C. W. 1976. Suppression of boll weevils 

 with grandlure-baited trap crops. In Detection and Management of the 

 Boll Weevil With Pheromone. Tex. Agric. Exp. Stn. Res. Monogr. 8, pp. 

 53-61. 

 Trap-crop systems employing early planted strips of cotton, grandlure, and 

 insecticide were tested for effectiveness in suppressing boll weevil popula- 

 tions during the 1972-74 seasons. These tests were designed to develop and 

 evaluate systems in which overwintered boll weevils are aggregated into a 

 small portion of the field where they can be easily and economically con- 

 trolled. Thus, if the system functions properly, the major portion of the 

 cotton field will support a smaller weevil population than normal. There- 

 fore, damage will remain below an economic ic«/el, or at least economic damage 

 wi^l-sc€4jr -significantly later than in the absence of a trap crop. Results 

 of trap-crop tests reported here fail to show consistent clear-cut e::ample8 

 of effective weevil control. The greatest difficulty encountered in imple- 

 menting trap-crop systems was that of obtaining trap-crop cotton which was 

 significantly more advanced in growth than the regularly planted crop. 

 Although some test indicated weevil suppression, the practicality of using 

 trap crops in a weevil control system is questionable at this time. 



