10 RELATION OF DROUGHT TO WEEVIL RESISTANCE IN COTTON. 



Though the conditions of drought that gave the complete protec- 

 tion against the weevils were generally so severe as to interfere seri- 

 ously with the growth of the plants and would undoubtedly have 

 prevented the development of any considerable crop unless rain had 

 come, the facts are of interest in their practical bearings upon the 

 problem of weevil resistance. The complete cessation of weevil 

 injuries, even after the weevils had survived the winter in unusual 

 numbers and had begun to feed and breed in the buds of the young 

 plants, makes it evident that the highest importance must be placed 

 on the dry weather. The values of special weevil-resisting varieties 

 and of special methods of culture must also be considered as means 

 of gaining greater advantages from dry weather. 



EARLY PLANTING IN DRY REGIONS. 



The object that has been sought by early planting and by the use 

 of early varieties is to give the cotton an opportunity to set as many 

 bolls as possible early in the season, before the weevils have become 

 numerous enough to infest all the buds and bolls and thus set a 

 limit to the crop. A farmer who plants too late may have his cotton 

 stocked with weevils from fields planted earlier by his neighbors and 

 may suffer more seriously than they. 



The best plan would be for a community to plant all of its cotton 

 as nearly as possible at the same date. The date should be selected 

 with a view to securing the most rapid development of the crop, and 

 for this it is necessary that the plants make prompt and continuous 

 growth. The amount of weevil injury is determined by the relation 

 between the development of the cotton and the reproduction of the 

 weevils. Any loss of time on the part of the cotton by delay or 

 interruption of growth can only increase the relative proportion of 

 weevil injury and diminish the crop. Anything that gives the cotton 

 an advantage over the weevils should be taken into account in the 

 problem of weevil resistance, whether the advantage is gained by 

 methods of culture or by specialized characters of the plants them- 

 selves. The largest results are to be obtained by combining the 

 cultural and the biological factors. 



If each farmer attempts to plant earlier than his neighbors, the 

 product of the community is likely to be reduced, for two reasons: 

 Cotton that is planted too early may be injured so that maturity is 

 retarded instead of being hastened and the weevils bred in early cot- 

 ton may inflict increased injuries upon the later fields. Cotton that 

 has been severely checked by cold or by extremes of wet or dry 

 weather in the early stages of growth often suffers a permanent in- 

 jury, either by being stunted in growth or by becoming abnormal 

 in other respects. A smaller crop is obtained and that of inferior 

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