CONTROL OF THE BOLL WEEVIL. 9 
they were standing. The runners are provided with knives made of 
sharpened metal. Old saws have been found well adapted to the 
purpose. It is important to provide a metal runner at the rear end 
of the machine to prevent sliding. This runner is designed to run 
an inch or more beneath the surface of the ground. The device can 
be made by any blacksmith at a cost of about $4. It will cut and 
windrow from 10 to 15 acres of stalks in a day. 
There is a disadvantage in cutting the stalks at or near the surface. 
of the ground; this is that if warm weather follows, many of the roots 
give rise to sprouts that will furnish food for the weevils. On this 
account the process is less effective than uprooting the plants. 
Wherever the stalk cutter is used it should be followed by plows to 
remove the roots from the ground. 
There is another important means by which the winter mortality 
of the weevil may be increased. This is by removing the hibernating 
quarters or destroying them after the weevil has gone into hiberna- 
tion. Many of the insects are to be found in the winter in trash and 
débris in and about cotton fields. The more shelter provided in the 
form of weeds growing about the fields, the more favorable the con- 
ditions will be for the insect. By the burning of such hibernating 
shelter as is found in the cotton fields and in their immediate vicinity 
a farmer can cut off a very large proportion of the weevils that would 
otherwise emerge to damage the crop. 
The prolonged period of emergence from hibernation gives the 
planter another important advantage over the weevil. The period of 
emergence from hibernation extends, in normal seasons, to practi- 
cally the 1st of July. In fact, except in one of the experiments per- 
formed, the last weevils did not appear until after the 20th of June. 
In Texas it was found that 75 per cent of the emerging weevils 
appeared after April 8, and in Louisiana 64 per cent. In Texas, 
after May 1, in all the experiments, from 4 to 18 per cent of the sur- 
viving weevils appeared. In Louisiana, after May 1 from 30 to 40 
per cent emerged. 
Tt is obvious that the fact that many weevils do not appear until 
long after cotton can be planted and brought to a fruiting stage is a 
very great advantage to the planter. A portion of a crop, at least, 
can be set before the weevils have become active. Usually it is possible 
to plant a crop sufficiently early to have it set some fruit before 
much more than 50 per cent of the surviving weevils have emerged. 
Attention was directed to the fact that the development of the 
weevil is much slower in the early portion of the season than later. 
For instance, at Vicksburg, Miss., the average period of development 
in April is 30 days, and in May 19 days. In June the period is 
shortened to 15 days. Consequently, the planter has an opportunity 
500 
