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Insect surveys appear to be indicating that the
Eastern spruce budworm
is primarily attacking white spruce populations and to a much lesser extent the true firs, subalpine
fir and balsam fir. The
Tent caterpillar and
Large aspen tortrix
are primarily attacking trembling aspen populations and to a much
lesser extent populations of poplar and paper/white birch.
Since 1986, the
Eastern spruce budworm
has been the primary insect population of concern in the Fort Nelson Forest District. The
2003 annual report
(very large 4.6 Mb pdf file) produced by the
Canadian Forest Service, Pacific Forestry Centre (PFC)
in Victoria has shown that the population trend appears to be headed downward. For greater detail on the
modelling of the eastern spruce budworm outbreak and subsequent collapse in the Fort Nelson area refer to
the on-line publication
Spruce Budworm Project Summary
produced by the
Pacific Forestry Centre (PFC)
in Victoria.
In the wake of the eastern spruce budworm outbreak in the Fort Nelson area, the budworm has weakened
spruce stands, either causing rise to
spruce decline syndrome
or accelerating the naturally occurring aging processes within these stands.
As a result of various factors, such as un-salvaged timber from wildfires and the attacks of
Eastern spruce budworm,
small isolated pockets of white spruce stands have become stressed. This could give rise to creating an
environment for spruce decline syndrome to take hold. Or simply the aging processes accelerating the
development of attributes that characterize more decadent stands.
A few of these stressed stands have subsequently had minor attacks from the
Spruce bark beetle
and other wood-boring insects. Notably to the northwest of Fort Nelson in the Irene Lake area,
northeast in the Kotcho Lake area and to the south-southeast in the Sikanni Chief River area.
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