118 
The Bulletin 
becomes so exhausted that the corn does not make a satisfactory growth, 
and hence it readily succumbs to the attacks of insects. Whereas, if 
proper crop rotation has been practiced, the corn would get a satisfactory 
start and would be strong and vigorous enough to withstand the attacks 
of insects to a certain extent at least. 
Figure 67. Experimental plots showing the effects of heavy applications of complete ferti¬ 
lizers. Row in center and on either edge of plot heavily fertilized. Other rows without 
fertilization. 
FERTILIZATION 
Fertilization is, perhaps, next to “time of planting,” the most impor¬ 
tant factor in the control of this insect. This is not, of course, the 
proper place to enter into a discussion of the proper fertilizer to use for 
corn, but it has been shown on one of our experimental plats that an 
application of fertilizer will make the plants grow much more rapidly, 
and hence be less liable to be fatally injured by the corn bill bug than 
plants which have not been heavily fertilized (Fig. 67). In the same 
way a heavy application of lime to land that is sour will make the 
plants grow much more rapidly and thus escape the attacks of the bill 
bug. The importance of lime may be further emphasized by the fact 
that very much of our corn land in the corn bill bug sections of the 
State is naturally very acid. 
The belief so prevalent in the corn bill bug sections that fertilizers act 
as repellents against the corn bill bug does not seem to be based on 
facts. Repeated experiments with various mixtures of fertilizers, air- 
slaked lime, tobacco dust, tobacco extract, and basic slag failed to show 
that the adult beetle was deterred from feeding and laying eggs in 
