My name is Doug Pitt I'm a research scientist with
the Canadian Forest Service, Canadian Wood Fibre Centre.
My primary focus of research is silviculture.
Harvesting practices in the boreal forest
have changed over the years.
Back in the early days the primary focus of management
was timber production.
More and more over the last several decades we've become
concerned with other objectives for forest
management, social objectives such as recreation,
aesthetics and in some cases spiritual values,
as well as environmental objectives,
maintaining wildlife habitat and food sources,
water conservation and so on.
The most common type of harvesting in the boreal
forest is clear cutting.
It's important to understand though why we use clear
cutting in the boreal forest.
One of the primary goals of our silviculture is to emulate
natural disturbances and in the boreal forest factors
like wind, fire, insects and disease play a very important
role in forest renewal.
These all function to create openings in the forest
that allow sunlight to reach the forest floor.
Species such as Jack Pine, Black Spruce,
Aspen have all evolved requiring more or less
full sunlight to regenerate and grow properly.
So any practice that aims to open the forest up to emulate
some of these natural disturbances can be classified
under the clear cut system.
So what we've seen is a move from fairly large clear cuts
with relatively geometric shapes to clear cuts that
include a lot more residual structure in them to provide
wildlife habitat and contribute to diversity.
We see this residual structure being left dispersed evenly
throughout cut-overs as well as grouped into islands
of intact pieces of forest that are left to maintain diversity
and provide wildlife habitat.
You have to understand that our boreal forest consists
of stands that are relatively even aged.
That means that the trees in the stand are all the same age.
They are like this because
they're what we call shade intolerant.
So the ecological benefit of a clear cut is to create
the environment required to regenerate
and grow an even aged stand.
And pre-settlement, our boreal forest existed as a patchwork
mosaic of these even aged relatively pure stands of
spruce, Jack Pine or Aspen.
While we strive to emulate natural disturbances with our
silviculture, that emulation isn't always perfect.
The road systems for example that we use to access
our harvest areas have no natural analog.
Fires for example are much less discriminating than we are.
So there are some differences that we strive to mitigate
through some of our silvicultural techniques
and management.
When a forest is managed sustainably,
only the growth of the forest is harvested essentially.
It's like a bank account where we have capital and interest.
And as long as we only remove the interest portion
in that account, we can maintain the principle.
A forest is exactly the same way.
We have growing stock.
The growth on that forest is what we should be harvesting.
If we harvest more than that, then we're not sustaining that
forest, we're not sustaining that bank account if you will.
Science has had a huge influence on our understanding
of ecological function.
And this is really reflected as an underpinning
to our operational practice today.
We've seen a lot of science contributing
to our understanding of partial harvesting practices,
mixed wood management, vegetation management,
pest and fire management.
And all of these contribute to our ability to manage our
boreal forest sustainably and to maintain our social license
to practice on public lands, which represent more than 90%
of the lands that we operate on in the boreal forest in Canada.