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regarding experiments with powdered arsenate of lead as a poison 
for the boll weevil. This substance has the advantage of being ab- 
solutely harmless to the plants, whereas Paris green applied to the 
tender terminal growth frequently causes the plants to become 
stunted, to remain so throughout their lives. Although the pow- 
dered arsenate of lead has this advantage, the question still remains 
as to whether enough weevils can be poisoned to result in any special 
benefit to the crop. The following is Mr. Newell’s statement on this 
subject: 
As it is, the profit to be derived from applying the powdered arsenate of 
lead when the cotton is in the budding stage can only be determined by actual 
tests in the field, in which the production of poisoned and nonpoisoned cotton 
‘both under conditions otherwise exactly alike) is carefully determined. 
It will be noted from Mr. Newell’s statement that no field experi- 
ments have been carried on to determine whether any direct benefit 
can be obtained from the use of powdered arsenate of lead. The 
Bureau of Entomology therefore urges that until further notice no 
farmers go to the expense of attempting to poison the boll weevil 
in any way. 
Many attempts have been made to cause poisoned substances to be 
attractive to the weevil by introducing sweets and other ingredients. 
All these have failed completely. Some known sweets, such as honey, 
have a slight attraction for the weevil, but not enough to assist in 
practical control even regardless of their expense. 
Contact poisons.—Poisons designed to kill the weevil by suffocating 
rather than by being taken into the digestive organs, have been pro- 
posed. They can not, of course, be effective against the immature 
weevils within the cotton fruit. The difficulties in reaching the adults 
are in their manner of work. Normally these insects are found inside 
the bracts of the squares, where they can not be reached by sprays. 
In fact, nature designed the bracts to prevent the heaviest rains from 
reaching the square within. An additional difficulty is in the expense 
of applying sprays, not only on account of labor, but on account of 
the special machinery that is necessary. Although there is some very 
remote possibility that dry poisons may be found of assistance in con- 
trolling the weevil, on account of the facts mentioned it is not at all 
probable that liquid sprays can ever be used. 
Effect of confinement.—There is one peculiarity of the weevil that 
has led to many unwarranted claims as to the efficacy of remedies. 
The insect will die within a very short time when confined in a bottle 
or jar or even in a cage. Even when cages are placed over growing 
plants it is found that-numbers of the insects die and fall to the 
ground, though no poison has been applied. In many instances ex- 
perimenters have applied their preparations under such conditions 
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