19 



leaf worm is considered a friend instead of an enemj', and planters who 

 liave several thousand pounds of poison on hand at the present time 

 declare that they will not use another pound of it. 



SOME REASONS FOR APPARENT EFFECTIVENESS OF PARIS 



GREEN. 



There are several circumstances which have led some users of Paris 

 green during the growing season to conclude that the applications of 

 poison were effectual, but upon closer examination it may be seen that 

 these appearances depend upon other causes than the application of 

 poison. The active life of the hibernated weevil may extend over 

 from 60 to 80 days, so that during the latter part of Ma}^ and during 

 June a majority of the weevils which lived through the winter, having 

 by that time deposited their eggs, are dying naturally, and these dead 

 weevils being found in the poisoned fields have given the impression 

 that they were killed b}' the Paris green, A good illustration of the 

 dying of hibernated w^eevils was seen in a field of Mr. Jose Cassiano, 

 San Antonio, Tex., who found many dead weevils in a tield early in 

 June, and concluded that ants were killing them. An examination 

 showed that the ants were simply carrying off weevils w' hich had died. 

 Others have reported that after poisoning their fields they have found 

 as manj'^ dead weevils in the part not poisoned as in that to which 

 poison was applied. At Runge the business men made the following 

 test before deciding whether the}" should recommend the use of Paris 

 green: Two plants were placed under screens, one poisoned and one 

 not poisoned, and upon each of these plants was placed the same num- 

 ber of weevils. They found that as many weevils died on the plant 

 which was not poisoned as upon that which was poisoned. 



Another apparent reason results from the condition called "spotted 

 crop,"' which has been very common this year. One field where there 

 is no apparent reason for such condition will show a good crop on 

 some parts of the field while other parts will have nothing, and this 

 unevenness exists without regard to the poisoning of the field. If it 

 should happen that the poisoned part should produce the best crop, 

 the owner w^ould naturally conclude that the poison was the effective 

 cause. As happened in several instances, however, the part of the 

 field naturally inclmed to produce a poorer crop was poisoned and 

 produced very little, while the nonpoisoned portion of the field vielded 

 a much better crop. 



In many cases where poison was applied the farmer provided no 

 adequate check upon the poisoned area. In such cases there is no way 

 of telling how much or how little effect the poison had. The owner 



