146 FOREST PROTECTION AND CONSERVATION 
YOUNG POPLAR. 
Although only twelve years old some of them are 
five inches in diameter breast height. 
Photo by Maine Forestry Dept. 
2 
spruce and fir, 
showing the 
characteristic 
work of this in- 
sect. In some 
cases the empty 
pupal skins still 
adhered to in- 
jured twigs. 
Along the wood- 
land trail from 
York’s Camp, 
Loon Lake, to 
Richard - 
son’s Camp, Ken- 
nebago Lake, 
quite a number 
of the balsams 
have been killed 
during the last 
several years, 
but a large per- 
centage even .of 
the larger 
growth had es- 
caped. But rela- 
tively few spruce 
trees were dead, 
although many 
showed the ef- 
fects of partial 
defoliation in the 
presence of dead 
branches and leaders. The work of the caterpillar during the past 
summer (1919) has resulted in only partial defoliation, and in 
practically all cases observed, the trees will doubtless recover. Ap- 
parently the present infestation has at no time been disastrously 
heavy in this locality. 
The observations in Piscataquis County were made during the 
latter part of July in company with Dr. C. T. Brues, of the Depart- 
ment of Entomology of Bussey Institution, Harvard University, 
and Mr. H. B. Shepard, Forester for the Eastern Manufacturing 
