IBl 



fields all growth of cotton ceased. As the condition of maximum infes- 

 tation had been reached by that time, the complete removal of foliage 

 earl}^ in August allowed light and air to reach the unopened bolls of the 

 bottom crop and hastened their maturity. For this reason alone many 

 planters consider the leaf woitq a friend rather than an enemy. In con- 

 sidering the effect which this defoliated condition must have upon the 

 boll weevil, it must be remembered that wherever weevils are present 

 in abundance there can be no possibility of a top crop. The work of 

 the leaf worms does not, therefore, reduce by any considerable amount 

 the yield which will be obtained. During severe attacks both foliage 

 and squares are wholly destroyed. Thus the leaf worm not onh^ cuts 

 off directly and effectively the food supply of the weevils, but it also 

 deprives them of shelter within a period of from 7 to 12 days. In 

 many cases the multiplication of the weevils becomes practicallj^ 

 stopped. Large numbers of the adults are forced either to move or to 

 starve. Numerous observations have shown that multitudes of these 

 adults die under these conditions in the field, and it is also certain that 

 the condition of the cotton forces a general movement or migmtion of 

 very large numbers of weevils when accompanied by favorable weather 

 conditions. It is natural to suppose that this generally forced move- 

 ment may result in a longer migration than would take place under 

 more favorable food conditions. This of course would be unfortunate 

 so far as the adjacent territor}^ is concerned. It appears that exactly 

 these conditions of defoliation, accompanied by favorable weather con- 

 ditions, prevailed in east Texas during the autumn of 1904, and it is 

 possible that they account in some degree for the long flights, which 

 must have been taken by multitudes of weevils, covering in the course 

 of this migratory movement a strip SO to 70 miles in width. 



If we turn our attention to subsequent conditions in the original 

 field, we will find that the defoliation is really there a blessing. By 

 hastening the maturity of bolls already formed the season is shortened 

 and the way cleared for early destruction of the stalks. By complete 

 and repeated defoliations the leaf worm accomplishes for the planter 

 a partial early destruction of the plants. Fall development of the 

 weevils is checked. Unsheltered adults perish or leave the fields, and 

 inevitably the number of weevils hibernating there becomes very 

 greatl}^ reduced. It is perhaps unfortunate that the leaf worm seldom 

 works uniformly throughout a field. Especially around the edges of 

 the field large numbers of plants escape its attack, and not infi-e- 

 quently patches of considerable size in the midst of a field still remain 

 green, while surrounding portions are completely defoliated. Upon 

 the green areas the weevils gradually become concentrated, and there 

 they not only exist, but may also i^eproduce somewhat until hiberna- 

 tion time arrives. It should not be thought, therefore, that the leaf- 

 worm has done ail the work of the destruction for the planter, but by 



