52 NEW YORK STATE MUSEUM 
the beetles were placed upon the leaves. There was very little 
feeding the first day, more the second and eventually the insects 
succumbed as recorded in 1899. The important point is that elm 
leaf beetles will feed upon poisoned foliage only when compelled 
by hunger and, as a consequence, thorough spraying is necessary 
if one would secure satisfactory results. 
Results of spraying for elm leaf beetle in New York State. 
We have repeatedly stated that well-sprayed trees should keep 
their foliage green and vigorous throughout the season. Further- 
more, trees weakened from injury by this insect should be able to 
regain their vigor in large measure. Systematic spraying for 
this pest has been in progress in some New York communities 
for over ten years, and it may be instructive to review the situation 
and see what has been accomplished. There is no question but that 
these annual applications have been of material service in protect- 
ing the trees. This is quite different from admitting that the 
spraying has in all cases been satisfactory. The defects in treat- 
ment as ordinarily practised were especially apparent in 1911, be- 
cause the extreme drought of that season served to emphasize the 
work of the beetle and led many to question the efficacy of the 
application. The Entomologist at that time examined the trees in 
several communities and was forced to conclude that the unsatis- 
factory results were due to poor work. The foliage of many trees 
here and there and that of most of the lower branches were in 
relatively good condition, while numerous trees had much of the 
foliage badly browned, this being especially true of the upper 
branches in the taller trees. Too many have tacitly assumed that 
any kind of spraying would give results, whereas, as shown by 
experiments detailed above, nothing but the most thorough work 
will result in keeping the trees in full vigor. 
The elm leaf beetle, as is well known, first became well estab- 
lished in the lower portion of the Hudson valley. There are a 
number of cities and villages in that section where elms, especially 
the Scotch and English elms, are conspicuous by their absence. A 
very large proportion of such trees have succumbed to this pest 
in the city of Troy since 1895. The writer has watched this pro- 
cess of destruction in Albany and vicinity for over fifteen years. 
The earlier portion of this period was marked by extensive local 
injuries to European elms which were subsequently approximated 
only in 1911 when the beetle was so generally destructive to 
American elms. It was a time when the necessity of spraying was 
