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might conclude that the field to which he applied poison jdelded much 

 better than it would have done if not poisoned, whereas his neighbors 

 who did not use poison could frequently' show as good or even better 

 crops than the man using poison. 



It is an unquestionable fact that many persons are ver}- responsive 

 to suggestions. A patient having taken medicine expects to improve, 

 and may recover if the remedy applied were not injurious, even if it 

 were not helpful. In the same way a planter, having applied what 

 appeals to his mind as a remedy for the boll weevil, will expect beneficial 

 effects to follow the application. He will look then for, and probably 

 find, dead weevils, many of which died a natural death. He will 

 examine the plants with care, and as the hibernated weevils die off in 

 numbers, while the development of their progeny is slow and gradual, 

 he will notice what is frequentl}', if not generally, the real condition, 

 that from the middle to the last of June, or, more exactl}', from four 

 to six weeks after the first squares become about half grown, fewer 

 adult weevils are to be found in the field than could be found when 

 squaring began. Then again the rapidl}' increasing number of squares 

 so greatly decreases the proportional number of weevils that it seems 

 that weevils have almost entirely disappeared. When the cotton opens 

 the user of poison is likel}' to think that he can see a marked differ- 

 ence in favor of the treated cotton. As an example of this may be 

 mentioned two fields in Cuero, one of which was poisoned twice and 

 one three times. When the cotton was opening the owner stated that 

 there was a distinct gradation between the cotton not poisoned, that 

 poisoned twice, and that poisoned three times, but upon picking he 

 found that there was practically no difl'erence in the 3'ield under the 

 three conditions. Other instances of this tendency could be given. 



The difficulty of estimating the quantity' of cotton a field will yield 

 often leads to wild predictions on this point, whereas picking weights 

 show that there was little or no difl'erence. Of the planters whose 

 experiments have been reported in this bulletin, it will be noticed that 

 many who used poison on their plantations invariably applied it to the 

 improved varieties, if they had planted any such varieties. Messrs. 

 Zachary, Purcell, and the planters at Hearne did not plant King or 

 Territory seed, while the others did. Mr. Houston poisoned a field of 

 seppa cotton situated in town. The application of the poison to 

 improved varieties was in a large measure responsible for the apparent 

 success of the poison treatment. As a matter of fact these varieties 

 invariably yield more than native cottons without any special atten- 

 tion whatever. 



Another important error has l)een due to the fact that early appli- 

 cations of Paris green have prevented defoliation by the caterpillars. 

 Consequently, many poisoned areas have had the appearance of yielding 



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