New York AGRICULTURAL EXPERIMENT STATION. 33T 
SHOULD SPRAYING ALONE BE DEPENDED UPON IN COMBATING THIS 
INSECT ? 
Although the results in the above experiments are very gratify 
ing in favor of spraying, in many seasons it will be found imprac- 
tical to depend upon this means alone in combating this insect. 
Usually the willows are too large before time for the third treat- 
ment to spray to the best advantage and hence the machine should 
be brought into use for a short time if necessary. On newly-. 
planted fields, however, spraying will be found of special ad- 
vantage in keeping off the insects while the willows are getting a, 
start and before they are high enough for the machines. 
IMPORTANCE OF A UNITED EFFORT OF THE WILLOW GROWERS. 
Insects which migrate as readily as the cottonwood leaf beetle. 
will quickly spread over a community where their food plant is. 
extensively grown. The adults of this species fly readily and’ 
probably for quite long distances. In the fields about Syracuse, 
they literally swarm upon the willows, coming from all directions, 
‘especially from neglected fields, which of late years are becoming 
common in this community. A neglected field of willows means. 
that the beetles will breed there unmolested and as food becomes 
short or as migratory instincts dictate, will seek other fields in the. 
vicinity. Several illustrations of this kind came to the writer’s. 
notice at Liverpool. Willow growers whose fields were in the. 
vicinity of neglected fields suffered greater loss from injury to the. 
willows, or were put to greater expense in combating the insect 
than were those whose neighbors united with them in an effort to. 
check the pest. 
RECOMMENDATIONS. 
Begin spraying early in the season. Make the first application 
‘before the beetles become numerous and follow: it by one or two. 
more a week or 10 days apart. 
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