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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 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 cages. 
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 
increased the crop. In any case the topping of plants can probably 
do no harm in fields that are being damaged by the weevil. It is 
probable that the general results will be beneficial in causing the 
more rapid growth of the crop on the lower and middle branches. It 
has never been possible to demonstrate this in an exact way. Never- 
theless, for the general effects stated the topping of plants is included 
among the recommendations that should be followed, although as 
one of minor importance. 
COTTON LEAF-WORM AND BOLL WEEVIL. 
The relation between the formerly dreaded leaf-worm or so-called 
“army-worm” and the boll weevil deserves special attention. A 
quarter of a century ago the efforts of entomologists and planters 
were directed toward some means of destroying the leaf-worm. 
The use of Paris green was found to be effective. Various changes 
in the general system of cropping cotton also caused the injuries of 
the leaf-worm to become less conspicuous year after year. Even up 
to the time of the spread of the weevil into Texas, however, poison- 
ing was a more or less regular operation on all cotton farms. The 
insects never did any considerable damage before the middle or latter 
part of the season. The object in destroying the leaf-worm was 
that it prevented the maturity of a fall crop. For this reason the 
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