1925 ] Efficiency of Birds in Destroying Larvce of Corn Borer 31 
from quite a number of cornstalks. They are able also to shred 
infested corn stubble and take the larvae in the more exposed 
positions, but apparently are not able to reach the larvae con- 
tained in standing stalks. 
In the fall of 1922, when it was apparent that the birds were 
becoming a really important factor in the reduction of the num- 
bers of the corn borer, experiments were undertaken to determine 
how extensive such feeding was. These experiments were also 
carried on during the winter of 1923-1924. The object of this 
work was to obtain information on the extent of the combined 
feeding by all species of birds concerned rather than the extent 
of feeding of any particular species, the intention being to obtain 
as far as possible a picture of the present importance of birds as 
a group in relation to this insect rather than a study of the value 
of any one particular species. 
The studies pursued during the fall of 1922 and the spring of 
1923 may be treated under two heads; first, the extent of bird 
feeding on the larvae in infested cornstalks placed in the field 
for this purpose; second, the extent of feeding by birds on larvae 
in host plants that remained undisturbed in natural positions 
during the winter. 
In the first part of this work twenty representative locations 
were selected throughout the infested area of eastern New Eng- 
land. In each of these locations ten stakes were set upright in 
the soil, there being six infested stalks fastened to each of these 
stakes. The three following types of corn were represented at 
each location: pop corn, sweet corn (Golden Bantam) and field 
corn (Longfellow Flint). Counts of the larval population of 
representative stalks during the fall gave an average figure as to 
the number of larvae expected from each stalk, and from this 
average the number of larvae expected from each station was 
computed. This series of experiments was placed in the field 
in November, 1922, after all larval activity had ceased, and the 
stalks were collected in April, 1923, before larval activity had 
commenced in the spring. The chance of losing an appreciable 
number of larvae by migration was small, since during this 
period the larvae were entirely dormant and inactive. Of these 
twenty experiments five showed extensive feeding by birds 
