CHINCH BUG WEST OF MISSISSIPPI RIVER. 51 
numbers that reach maturity, many young being killed during a 
period of wet weather attended by hard dashing rains. Dry weather 
is most favorable to their development in abundance. The injury to 
wheat and corn is often severe, sometimes resulting in almost com- 
plete destruction of the latter crop after serious injury to the former. 
During the severe winter of 1909 and 1910 about 20 per cent 
of the bugs died normally in the clumps of red sedge grass, where they 
hibernate. 
Experiments in Kansas made during the winter of 1909-10 showed 
that as high as 75 per cent of the hibernating chinch bugs could be 
killed by burning this grass. The best time to burnis in the fall, when 
the grass is as dry as possible. It is not necessary that the flame come 
in actual contact with the bugs. 
The effectiveness of the burning is almost entirely dependent 
upon the cooperation of the farmers in infested localities. Neglect 
‘to destroy chinch bugs collected in these grasses will often result in 
serious injury, if not indeed a complete destruction of wheat, corn, 
cane, and kafir. . 
Next to burning, the dust and coal-tar barriers are the most 
effective remedies, and should be used while the bugs are migrating 
from wheat to corn. These barriers must be properly made, and 
demand constant attention to be of any value. 
Many bugs can be killed while massed on the first rows of corn 
by applying a torch or spraying with kerosene emulsion or proprietary 
spraying materials. 
Plowing under infested crops is not recommended unless the work 
is done very thoroughly and followed by a crop not susceptible to 
chinch-bug attack. 
Barriers made of piles of green corn are of no value, and are not 
recommended. 
The ‘‘ white fungus,”’ can not be depended upon to exterminate the 
chinch bugs. This fungus is very dependent upon moist weather 
conditions for its rapid development and diffusion. It can usually 
be secured by collecting live or dead chinch bugs from the sedge 
grass, and placing them under proper conditions of temperature 
and moisture. This fungus has many host insects, and is generally 
present where chinch bugs are found in destructive numbers. 
Laboratory experiments show that this fungus is present in greatest 
abundance among old spent adults, or those bugs that are in a 
weakened condition. Also that it will grow upon dead bugs. This 
will partially account for the fact that the time of its greatest abun- 
dance in the fields occurs after the hibernating bugs have laid their 
eggs and are dying normally. These bugs have performed their mis- 
sion of laying eggs, and are comparatively harmless, 
