| dc.description.abstract | Historically in Canada, old-growth forest preservation concerns, research, and
analyses have centred on the stately coniferous forests of British Columbia (e.g.,
Clayoquot Sound). Within the past decade, however, the forests of Ontario have
also come under scrutiny for their old-growth values. The Timmins Forest, a
Sustainable Forest License, provides the background for this case study of Ontario’s
old-growth forests. Old-growth is defined conceptually as an integral landscape
element, differentiated at the stand level by age The principal objectives of this
study were to develop and examine the temporal impact of various timber harvest
scenarios on the old-growth component of the forest. To support this analysis,
silvicultural options for the creation of old-growth structures at the stand level were
outlined for the boreal species under examination. One hundred-year simulation
scenarios were run on a forest model called HSG. HSG operates by tracking the
spatial identity of individual forest stands through time. As age and time increments
are simulated, HSG updates stand successional changes and inventories, applies
harvests, and allocates and schedules silvicultural treatments. Indicators for
analysis included long-run sustained yield versus growing stock, and the percentage
of the landscape in the old-growth condition per species. The scenarios ranged in
design from no harvests, no silviculture, to the use of “old-growth windows” (where
stands were protected from harvest) to the use of intensive silviculture. Results
show that old-growth supply is maximized across the boreal species when a
program of no harvests is undertaken. Protecting stands from harvest for a specified
number of years provided the least amount of long-run sustained yield over time.
Intensive silviculture increased harvest levels at the expense of old growth. The
Benchmark Scenario provided the best option for the provision of both inventories of
old-growth and long-run sustained yield.
Forest resource managers have the basic simulation tools necessary to measure
and manage for old growth, but need to perform additional analyses such as cost-benefit-analysis to evaluate the role of old growth in the landscape context.
Clarification and refinement of such methodologies and simulation tools will lead to
the improvement of forest policies designed to create and manage sustainable forest
management programs. | |
