CONTROL OF GIPSY MOTH BY FOREST MANAGEMENT. — 1133 
Basswood occurs very much scattered in the infested region. It 
grows to advantage only on the best sites and should be eliminated 
from all others. 
Beech occurs most abundantly in the northern portion of the 
region. It grows slowly and is liable to become defective before ma- 
turity. It is perhaps the least liable to damage of any Class I trees. 
_ Paper birch demands a great deal of ight and is not abundant in 
mixed stands. Where it occurs in abundance it is in great demand 
for spool and novelty wood. Scattered specimens may be replaced 
with species which are less liable to gipsy-moth attack. 
Tamarack is nowhere abundant in the infested region. It is a 
tree which can well be cut out when found outside of pure stands. 
It is the only conifer which is eaten by the youngest gipsy-moth 
larvee. : 
Class II (p. 9) is composed of eight species of trees on which 
gipsy-moth caterpillars in their earliest stages do not feed, but upon 
which they do feed in their later stages. Young caterpillars must 
have food, and if this is not available they can not attain the point 
in their development where they can feed on the trees of this class. 
Hence if stands of these trees have in their vicinity no plants upon 
which the young caterpillars can feed, the stands are practically im- 
mune from attack. Trees of this class can therefore be safely grown 
in pure stands, in mixture, where conditions permit, with one 
another, or in mixture with Class IV trees. 
Stands composed largely of one or more of the species of this class 
can be made immune from gipsy-moth attack by removing the plants 
which may provide young larve with food. Since most of the spe- 
cies which are susceptible to gipsy-moth attack are deciduous, pro- 
vision in this case will have to be made for the suppression of the 
sprouts which follow cutting. 
Trees of this class may be substituted frequently for removed trees 
of species susceptible to moth attack. The white pine is particularly 
important in this respect, owing to its commercial value, rapidity of 
growth, and adaptability to a variety of sites. The red pine, while 
somewhat slower growing and of slightly less value, is also a valu- 
able tree and deserves particular consideration owing to its immunity 
from the white-pine blister rust. 
Chestnut is the only deciduous tree of this class. It grows well 
and yields a valuable product, but unfortunately is subject to attacks 
of the chestnut blight. In the light of existing conditions the propa- 
gation of this species can not be advocated. 
Class III (p. 9) is composed of 20 species which are not par- 
ticularly favored, but upon which a small proportion of gipsy-moth 
larvee may develop. Stands composed of any trees of this class and 
containing none of the trees of Class I would maintain slight infesta- 
tions and would rarely, if ever, be defoliated. 
