UTILITY OF BIRDS IN WOODLANDS. 107 
after month. The consequent weakened condition of the 
trees would invite the bark beetles and other borers which 
attack such trees, and, multiplying exceedingly, cut channels 
beneath the bark until all the vital tissues are 
destroyed. I have seen many trees defoliated 
by the gipsy moth that afterward succumbed 
to the attacks of these insidious borers, which i 
are probably the ultimate cause of the death Fig. 35.—De- 
of many defoliated trees. a a 
The destruction of these larve in their re- Py birds. En- 
larged. 
treats under the bark is effected mainly by 
insect parasites, predaceous insects, the various species of 
Woodpeckers, and possibly by Titmice. The adult beetles, 
when they emerge from their retreats in the spring, are also 
attacked by many birds. The Woodpeckers are most valu- 
able, because they drag from secret hiding places certain 
boring coleopterous and lepidopterous larvee 
that might otherwise destroy the trees. A 
single borer may be sufficient to kill a young 
’ tree, but the Woodpecker takes the perni- 
cious grub from its burrow, and by eating 
several at a meal may save many trees in 
Fig. 36.—Wood. the course of a year. 
pecker hunting When the European leopard moth ap- 
ee peared in New York and Brooklyn, caus- 
ing great havoc among the trees in the parks, it was feared 
that as the insect spread it would become a serious enemy 
to the trees of the entire country; but I was informed by 
Dr. John B. Smith, entomologist to the New Jersey Agri- 
cultural College Experiment Station, that this moth, while 
a pest in cities, was doing little damage in the country, 
where the native birds seemed to keep it in check. At 
first it looked as if the large larve, because of their habits, 
would escape the birds. They are borers, beginning life 
within the small twigs, and when these get too narrow for 
them they eat their way out and crawl down outside to larger 
twigs. It is then that they are taken by many native birds, 
though the “English” Sparrows do not appear to check them. 
Dr. Smith says that the Woodpeckers eat the female moths, 
