62 THE DISPERSION OF THE GIPSY MOTH. 
ous trees will probably furnish similar unfavorable food conditions, it 
seems very important to determine by careful experiment the sus- 
ceptibility to gipsy-moth attack of the various species of native trees 
in New England forests and to test different methods of thinning 
woodlands in order to reduce the infestation by furnishing unfavor- 
able food, and by so doing to prevent the area thus treated from 
becoming so badly infested as to enable caterpillars to be spread from 
it by the wind. These experiments are now under way. 
(3) The experiments conducted indicate that little spread by the 
wind will result unless badly infested areas exist. Inasmuch as the 
principal spread over a wide area is due to the wind, more attention 
should be paid to the proper handling of bad woodland colonies 
along the lines already indicated, in order to prevent widespread 
distribution. From the experiments conducted, and from the data 
examined, and as a result of interviews and conversation with various 
officials and parties interested in moth work, it appears that the 
spread of the gipsy moth at the present time by automobiles or 
other traffic is far less serious than heretofore. Already a large 
mileage of trees along trunk roads has been thinned and protected, 
so that the danger has been largely reduced in this way. Special 
attention has been given to many roads leading to and from summer 
resorts or camping places where automobile traffic is heavy during 
the summer, and as a result of this work and of the scouting which 
has been carried on in the outlying territory, which included an 
examination of the trees along many of the trunk roads in unin- 
fested sections of the State as well as an inspection of places, such 
as hotel grounds, where touring parties would be likely to stop, it 
has become quite evident that in the last year or so the danger of 
infestation by means of automobiles has been greatly reduced. This 
would indicate the desirability of reducing the thinning operations 
along roadways, except on those where the automobile traffic is the 
heaviest during May and June. 
(4) The work which has to do with the determination of the 
limits of spread of the insect, and which is known as the scouting, 
is of great importance. This is being carried on in the outside in- 
fested towns and in those adjoining, and too much stress can not be 
laid on its thorough prosecution. The men actively engaged in it 
should be instructed thoroughly in regard to the best methods of 
thinning woodland in order to control the moth, so that practical 
advice can be given to the owners of forest land to stimulate them to 
take proper measures for protecting their property before the infes- 
tation becomes serious enough to cause severe injury. 
o 
