THE BOLL WEEVIL PROBLEM. 35 
large places it will undoubtedly not often be found practicable to 
carry on this process. In an experiment performed by the Bureau 
of Entomology on a plantation worked by convict labor, giving the 
optimum conditions for the experiment, no results whatever followed 
thorough pickings twice each week for two months in the spring, 
beginning with the appearance of the first weevils. In another in- 
stance, at Gurley, Tex., more than 40,000 weevils were picked on an 
area of 8 acres by means of paid labor, beginning in April and con- 
tinuing until July. On the 8 acres where this work was done a crop 
of about 50 pounds per acre in excess of that on other areas was ob- 
tained. This was not sufficient, however, to pay for more than a 
very small fraction of the work done. From these and other experi- 
ments the Bureau of Entomology recommends in a guarded manner 
the picking by hand of weevils and squares. Undoubtedly good 
may be accomplished under certain conditions, but planters should 
be careful not to depend too much upon it and not to make too great 
an outlay for it. The subject is being investigated carefully in 
Louisiana. In due time a full report will be published. 
Disposition of adult weevils and infested squares.—W hen adult weevils 
are picked by hand they should be killed by means of oil or fire or 
buried deeply in the ground. When infested squares are picked, how- 
ever, an entirely different procedure should be followed. Many of the 
weevil larve in the infested squares will be found to harbor parasites. 
It is entirely practical, as has been pointed out by Mr. Wilmon 
Newell, of the Louisiana State Crop Pest Commission, to let these 
parasites develop and continue their work against the weevils in the 
fields. This is done simply by placing the infested squares in wire 
eages. The parasites, on account of their small size, will escape, while 
the weevils soon die from a lack of food. The meshes of the wire of 
the cage should be at least 16 to the inch. However, some weevils will 
escape through this mesh, and about 5 per cent through a 14-mesh 
screen. Even if the finer wire can not be obtained, it is advisable 
to use what can be had. A calculation will show that there is a direct 
advantage even if a few of the weevils escape. if all of the parasites 
do. By burning or destroying the squares in any other way the 
farmer is simply working! against and counteracting an agency in 
the control of the weevil that is much more important than any 
amount of hand picking he is likely to be able to do. 
TOPPING OF PLANTS. 
The practice of topping plants is sometimes recommended for 
fields infested by the boll weevil. The results of work by different 
experiment stations have shown that topping has exceedingly un- 
certain general results. As often as otherwise it decreased instead of 
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