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THE MEXICAN COTTON -BOLL WEEVIL. 



In the senior author's experience of 10 years onlyone example of a top 

 crop in a weevil district has been seen. This happened in the vicinity 

 of Brownsville, Tex., in 1911. The production of a few bolls on the 

 tops of the plants was due to a rare combination of exceptional influ- 

 ences, including very dry weather during the summer, defoliation at 

 an early date by the cotton worm, and late rains after the weevils 

 were greatly reduced in numbers. 



Neither the very remote chance of gathering a top crop nor the 

 actual injury which is being done to the crop of the succeeding year 

 by allowing that growth to continue until frost kills it is generally 



Fig. 18.— Status of the boll weevil in Texas in August, 1910: percentage of infestation of all forms. 



(Original.) 



appreciated by planters. Because of the apparent abundance of 

 squares and the presence of many blooms the plants are allowed to 

 stand long after they might have been destroyed to the great benefit 

 of the next crop. As is the case in the early spring, however, the 

 abundance of squares increases greatly the production of weevils, 

 and though a few bolls may set, they are almost certain to become 

 infested before they reach maturity. Every condition, therefore, 

 contributes to the production of an immense number of weevils very 

 late in the season and at just the right time for successful hibernation. 

 As a result, far greater injury is done to the crop of the following 



