14 THE BOLL WEEVIL PROBLEM. 
erned partially by the prevailing winds. They may fly into hedges, 
woods, cornfields, haystacks, farm buildings, or other places. Speci- 
mens have been found in such situations, and also in considerable 
numbers in Spanish moss growing some distance above the ground 
on trees. A number of weevils also obtain hibernating quarters 
without leaving the cotton fields. These may crawl into cracks in 
the ground under grass, weeds, and other trash, and into the burrs 
from which the cotton has been picked. In some cases several thou- 
sand weevils per acre have been found hibernating in such situations. 
Here, however, the mortality is greater than where the protection is 
better. The majority of weevils that hibernate successfully do not 
pass the winter in the cotton fields. This has been shown by many 
experimental observations, and is demonstrated every year in the 
infested territory by the appearance of the first damage in the imme- 
diate vicinity of weeds and other places where conditions for protec- 
tion are favorable. 
- During the winter the weevils take no food and remain practically 
dormant. On especially warm days they may move about to a cer- 
tain extent. During the very mild winter of 1906-7 hibernating 
weevils were found moving about more or less throughout the period 
from November to March. 
The number of weevils hibernating successfully has been deter- 
mined very accurately for different conditions. Out of 25,000 weevils, 
2.82 per cent survived the winter of 1905-6. These weevils were 
placed in a variety of conditions that must have approached those 
which weevils must naturally encounter. The winter referred to was 
practically a normal one so far as temperature and precipitation 
were concerned. In extensive work during the winter of 1906-7, out 
of 75,000 weevils 11.5 per cent survived. As in the preceding case, 
these weevils were placed under diverse conditions in different cages. 
These conditions ranged from the most favorable to the least favor- 
able, 1. e., from an abundance of protection to practically none. The 
survival obtained is undoubtedly very close to that occurring under 
diverse natural conditions of that winter. It must be emphasized 
that the winter of 1906-7 was abnormally warm. It is undoubtedly 
true that the rate of survival was much higher than usual. It is 
supposed that the results of the previous year must approach the 
average. In other words, less than 3 per cent of the weevils entering 
hibernation can be expected to survive the winter under average con- 
ditions. The tremendous importance of still further reducing this 
percentage must be evident. 
Emergence from hibernation depends primarily upon temperatures 
in the spring, although there are other minor factors concerned. 
Generally, from the first to the middle of March the temperature has 
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