14 
But even here the effect was uncertain, as the writer had found the 
parasite present in this locality before the introduction was made. 
in the other case a larger consignment was sent from the same local- 
ity in North Carolina to Sumter, S. C., to be placed in a field of oats 
that the writer visited in company with the owner on the 16th of 
April, when parasites were found in considerable numbers. In this 
case the owner of the field, writing under date of June 18 and report- 
ing on the outcome of the experiment, said: 
I am sorry that the information to be derived from our experiments with the 
parasites is so indefinite. It just happened that other conditions probably over- 
came the aphis before the parasites had time to multiply sufficiently to get in 
their work. About the time that your box was received weather conditions 
changed somewhat from cool to warmer weather and the bugs seemed to dis- 
appear very rapidly. From the day the bugs disappeared, the oats, the only 
grain grown, began to improve, and while they will not make a full crop by any 
means, they are much better than we anticipated when you were here. 
This is, as the writer personally observed, also the history of the 
disappearance of the pest in western North Carolina, where both fall 
wheat and fall oats are grown and where no parasites were intro- 
duced, but where they were literally swarming on April 20. 
From all of this it would seem that throughout the greater areas 
over which this insect becomes injurious it has so far been impos- 
sible to assist the work in any way. We have apparently been wholly 
unable to aid the parasites in getting the upper hand. They accom- 
plished their work earlier in the Carolinas than in the West, but 
reference to the records of the Weather Bureau will show that the 
weather conditions as regards temperature were precisely such as to 
bring this about. d 
The only possibility of accomphshing anything by the artificial 
use of natural enemies of the “ green bug” seems to be in Texas and 
South Carolina, where the pest gets its start earhest, making its ap- 
pearance in the fields in spots of greater or less area in the fall or 
early winter. If these incipient outbreaks can be stamped out by 
farm methods, as indicated further on, or by the encouragement of 
parasites, or if they can be so weakened as to prevent the “ green bug ” 
from developing in such enormous numbers, it will serve to protect 
the grain crops not only of these two States, but of all those to the 
northward over which the pest ravages in seasons favorable for its 
development. The Texas Agricultural Experiment Station is con- 
templating an experiment whereby they hope, by the artificial intro- 
duction at the proper time of a large number of the natural enemies 
of the “ green bug ” into these spots of early infestation, to forestall 
a future outbreak. If this can be accomplished it will prove of great 
benefit to the farmers. Whatever the outcome may be, the experi- 
ment seems worth trying. 
[Cir. 93] 
