56 
JOURNAL OF ECONOMIC ENTOMOLOGY 
[Vol. 16 
logical problems crying to be solved. The scope of the present paper 
will only permit us to mention a few that are of particular impor¬ 
tance in Minnesota. The most outstanding of these is the problem of 
protecting our balsam and spruce forests from outbreaks of the spruce 
budworm. 
The outbreak in Minnesota has already involved the greater portion 
of our balsam spruce forests and it is practically certain that the small 
uninfested area in the northeastern tip of the state will be infested in 
1923. A very large proportion of the balsam in at least two-thirds of this 
area is already dead. There is every indication, that under pres¬ 
ent conditions we may expect repeated outbreaks of the budworm 
every thirty to fifty years. Is there not something that we can do to 
prevent recurring epidemics of this insect or if that is not possible can 
we not at least find some way of reducing the amount of damage? 
Another defoliating insect which seems to be of increasing importance 
in this state is the forest tent caterpillar. Recently there have been 
several rather extensive local outbreaks of this pest. Although they 
have not reached proportions comparable with that of the spruce bud¬ 
worm they are nevertheless important. The ever increasing amount of 
birch and aspen forest is apparently a factor in aiding the rapid increase 
of the tent caterpillar. It is very probable that this insect will be from 
year to year increasingly important in our forest economy. 
The larch sawfly although the epidemic is decidedly on the wane, is 
still a menace to be reckoned with. Tamarack on well drained soil 
grows very rapidly and in such situations promises quick returns when 
grown for posts and poles on a short rotation. The planting of this 
very desirable species cannot at present be recommended because of 
the possible danger of sawfly attack. The sawfly question is still a very 
fertile field for investigation, and it certainly does not present any 
greater difficulties than many of the problems already solved by ento¬ 
mology. 
One of the very live issues in forest insect work is the control of pests 
in freshly cut timber, particularly pulpwood. Much of this material 
is always held over a season for one reason or another and, if it cannot 
be placed in water, the losses due to borers is very material. It has 
been stated that the usual depreciation in a pile of pulpwood held over 
one season amounts on the average to 10 percent of its value. This 
means a depreciation of about one dollar a cord. We are now working 
on this question and hope to have soon a practical method of materially 
reducing these losses. 
