Department of Agriculture 27 



Predators 



Several predacious insects attack the boll weevil, chiefly in 

 the immature stage. By far the most important of these are 

 several species of ants, which chew into the square and destroy 

 the immature weevil. In some instances, ants are an impor- 

 tant factor in the control of the weevil, but ordinarily they do 

 not attack the weevil-infested squares until comparatively late 

 in the season, after it is too late for the crop to be benefited. 



The Annual Summer Rainy Season 



Profitable production of Sea Island cotton under Florida 

 conditions is complicated by the long, annual summer rainy 

 season. As a general rule, the wet season begins about July 

 1 and lasts from four to six weeks. During the rainy season 

 the time interval between weevil generations is shortened 

 and the annual summer migration occurs. This condition 

 prevents successful control of migratory weevils by the use 

 of poisons, increases boll rots and otherwise prevents profit- 

 able yields on all cotton except that planted extremely early. 

 WPA Entomologists have tested dusting, spraying and mop- 

 ping during the wet season for control of migratory weevils. 

 In the hands of experts midsummer poisoning operations 

 have shown a profit, but the operation is too complicated to 

 recommend for use by the average grower. 



Fig. 9 shows graphically the average annual distribution of 

 rainfall for the state as a whole. It is apparent that the win- 

 ters are definitely dry, while the summers are wet. If a good 

 crop of bolls has not been practically matured by the time 

 the rainy period arrives, the plants grow excessively and 

 mature the crop late. Also, weevils multiply very rapidly 

 during wet weather, and since there is no practicable method 

 of controlling this insect during excessive wet weather, the 

 crop is heavily damaged. 



