Report to:
Ray Schultz, Regional Manager, Ministry of Forests
Prince George, BC
on
Mixedwood Management Strategy for PA14 and
Spruce Understory Retention Policy by Slocan Group,
Fort Nelson Woodlands
Submitted by
J.P. (Hamish) Kimmins
Professor of Forest Ecology
Department of Forest Sciences
Faculty of Forestry
University of British Columbia
2424 Main Mall
Vancouver, BC
V6T 1Z4
April 27, 2000
1
Executive Summary
1. A field trip for problem identification and familiarization was undertaken in
August, 1999 in the boreal mixedwood forests in the Fort Nelson area that are
under the management of Slocan Group, Fort Nelson Woodlands.
2. Meetings were held in Prince George between the Ministry of Forests, Prince
George Region staff and Slocan Group, Fort Nelson Woodlands Group staff in
December 1999 and March 2000 with the objective of achieving agreement on a
variety of issues with respect to the management of boreal mixedwoods, but with
a focus on the question of the retention of understory spruce at the time of harvest
of deciduous stands.
3. The failure of these meetings to reach agreement on the extent of spruce
understory retention goals led to a second field trip to Ft. Nelson in April, 2000 to
clarify several details prior to the preparation of the opinion presented in this
report.
4. A major problem with respect to boreal mixedwood management is the lack of
landscape-level objectives for the spatial patterns and temporal dynamics of the
four major stand types being considered: conifer, conifer-leading, deciduousleading, and deciduous.
5. A second major problem is the lack of a satisfactory, ecologically based definition
of “mixedwoods” at the stand level. The lack of such a definition, together with
the lack of higher level landscape objectives and an apparent preoccupation with
intimate mixtures and even spacing, rather than the range of mixture types and
spacings seen in the unmanaged forest, appears to have lead to a regulation-based
approach to management by the MoF rather than the adaptive management,
objectives-based approach needed in a disturbance driven forest types such as the
boreal, especially since our knowledge and experience of managing these forests
is limited.
6. Practical limitations imposed by the northern climate, summer access problems
and human resource constraints combine to limit the choices that are available
within the over-arching and mutually agreed-upon objectives of supplying the
local mills, no overall cost increases and no negative change in fibre quality,
subject to the higher constraint of maintaining some target landscape objectives
with respect to forest composition.
7. Several recommendations are presented. These include, but are not limited to: 1,
the need for more explicit landscape and stand objectives that reflect the high
natural spatial variability, natural disturbance and temporal dynamics of these
forests. 2, the need for better working definitions that are ecologically based. 3,
establishment of a compromise between the Licensee’s proposal to protect spruce
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understory on 300 ha of the eligible stands (based on the mutually agreed-on
definition of eligibility) and the MoF’s desire to protect all eligible stands in order
to increase the representation of spruce in these forests. This compromise requires
the MoF to modify its present approach to aggregation within boreal mixedwood
stands; to replace an apparent preoccupation with intimate spruce/aspen mixtures
and even spacing with a policy that recognizes the continuum of spacing and
aggregation in unmanaged mixedwood stands in this area.
8. Several additional technical recommendations are presented that include
improved inventory, a change in the stumpage and cost allowance system with
respect to aspen, and the development and/or use of a new generation of
ecologically based decision support tools. The latter are needed to increase the
credibility of forecasts of stand development under different silvicultural and
harvesting strategies, so that adaptive management can be effectively undertaken
to achieve stand and landscape-level objectives once these have been established.
9. It is recommended that there be a five-year interim agreement during which these
proposals are tested for their efficacy in achieving objectives. During this time the
MoF, through LRMP and LUP processes, must establish the necessary definitions
and objectives without which useful progress towards the desired level of
stewardship of these forests is unlikely. At the end of the interim period, there
should be a review of progress, and further recommendations made where
progress or policies/practices have failed to achieve anticipated outcomes.
10. Studies should be commissioned to establish what is known of the biological
implications (e.g. wildlife; various measures of biodiversity) of different stand
structures and spatial aggregations in these forests at both the stand and landscape
scales. Concerns over the implications of structure and pattern for these values
were expressed during meetings and field trips, but it is far from clear that we
understand the relationships involved. In the absence of such knowledge, it is not
possible to support anything other than the currently poorly documented range of
structures and patterns that one can observe in unmanaged forests in this area.
Where this review reveals significant knowledge gaps, research should be
commissioned to obtain the necessary knowledge. In the absence of such
knowledge, an adaptive management approach should be taken rather than
imposing any particular policy in a rigid manner.
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1. Introduction: the context for the current issue
1.1 The ecological character of the boreal forest, and the role of disturbance.
The Canadian boreal forest is characterized by relatively frequent stand replacing or stand
maintaining disturbance by fire, wind and/or insects. It is commonly thought of as a
dynamic landscape in which shade-intolerant, disturbance-dependent, pioneer deciduous
hardwoods such as aspen and cottonwood are replaced through successional processes on
fresh to moist, and medium to high fertility sites by white spruce. This replacement can
come about as a result of spruce seedling recruitment at the time of, or shortly after, stand
replacing disturbance. Alternatively, it may be delayed until the opening up of the
overstory deciduous canopy as the pioneer stand develops, something that may be
delayed for a long period in the case of very vigorous, long-lived hardwood stands. In
either case, the spruce tends to form an understory of either clumped or scattered
individual trees, growing slowly in the shade of the aspen overstory. If the stand is not
reburned, the understory spruce may grow up into the canopy and eventually overtop the
aspen as the hardwoods senesce, converting an initially deciduous stand, through a
mixedwood of changing composition, to a pure conifer stand in the long-term absence of
stand replacing disturbance. The character of much of the boreal landscape is thus a
mosaic of pure deciduous hardwoods, pure spruce (or other conifers), or a mixture of the
two in either conifer-leading or deciduous hardwood-leading mixedwoods.
This linear model of succession from aspen to spruce can certainly be observed in boreal
forests, but it is far from a complete description of their natural dynamics. Depending on
the type of disturbance, the structure and species composition at the time of disturbance,
the severity of the disturbance and the area affected, the post-disturbance community may
have the same tree species composition as the pre-disturbance stand, or be quite different.
Aspen can return to aspen or develop into mixedwoods. Spruce can return to spruce, or
go to pure aspen or to mixedwoods. The mixedwoods can be an intimate, tree-by-tree
mixture, or a highly clumped irregular patchwork of aspen or spruce–dominated “mini
stands”. The key feature of the post-disturbance community is thus one of almost infinite
variability. Almost any combination of aspen and spruce and of stand structure and mini
stand patch size can be observed.
1.2 Harvesting wood from the boreal forest: “un-mixing the mixedwood”?
Forest harvesting in the boreal landscape has, until recently, focussed on spruce and other
softwoods. Exploitative logging of spruce in the past generally killed most young and
non-commercial spruce, and for a long time there was little or no silvicultural investment
to ensure spruce renewal. This converted many boreal mixedwoods to pure deciduous
stands, and many boreal white spruce stands to poorly stocked “brush fields”.
Concern over the lack of white spruce regeneration led to extensive research and policy
development with respect to site preparation and planting white spruce, and to retention
of understory spruce (advance regeneration and young (small) trees). Cutting, burning
and/or herbicides were used to eliminate or reduce the pioneer hardwoods which until
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recently had little or no commercial value and, therefore, no market. This policy
successfully converted a variety of pre-harvest stand types to pure or almost pure, evenage spruce, although there were also notable failures, delays and considerable expense.
However, with the development of commercial value for large peeler hardwood logs,
hardwood chips (for OSB) and hardwood pulp, and with concerns about the role of early
seral hardwoods in sustaining long-term site productivity, aesthetics, wildlife and
biodiversity values, interest has grown in maintaining hardwood and softwood mixed
forest, and in promoting pure deciduous forests where their growth is superior.
Managing boreal mixedwoods to maintain their mixedwood character is silviculturally
more challenging and can be much more expensive than converting them to deciduous or
coniferous monocultures. Such monocultures are not unnatural. As already noted, natural
disturbance produces a spatial complex of these two types of pure stands, together with a
diversity of mixedwoods that vary from “conifer leading” to “hardwood leading”, and
from intimate, tree-by-tree mixtures through various levels of clumping and aggregation
in mixtures, to a patchwork of small to medium-sized patches of pure spruce and pure
aspen. The latter is often promoted by the clonal growth form and root suckering of
aspen.
The spectrum of species composition, horizontal structure and vertical structure that
forms a continuum between pure deciduous and pure conifer, even age and relatively
uneven age, single canopy level and complex stand structures occupies much of the
boreal landscape, and clearly has importance for wildlife in providing habitat diversity.
There is thus the potential for conflict between the desirability of maintaining the
diversity of stand types arranged in largely unrepeated patterns across the landscape that
is characteristic of unmanaged boreal forests, and the silvicultural and economic
efficiency of reducing the complexity of mixedwoods by creating a mosaic of relatively
pure conifer and deciduous stands. Even if the overall landscape ratios of conifers and
hardwoods are sustained by the latter management approach, the intimacy of their
mixtures is reduced.
1.3 Concerns about landscape pattern and stand structural complexity.
Clearcutting mixedwoods results in even-aged forests, whereas fire, insects or wind
disturbance can produce either even-aged or multi-aged stands with scattered individual
trees or groups of trees that survive through until the next stand-replacing disturbance
event. Where disturbance leaves large living spruce, these act as seed trees and provide
different wildlife values compared with stands made up of young spruce growing up
under a deciduous canopy. Harvesting or simply cutting young spruce at the same time
as older, commercially valuable hardwoods are harvested results in the waste of several
decades of spruce growth, and extends the rotation time to produce commerciallyvaluable spruce logs. The desire to create future boreal landscapes that have the full
spectrum of stand types, including stands that are complex in structure and species
composition, as well as to capitalize on the advance growth of understory spruce, has led
to requirements that a component of the landscape be maintained in the “mixedwood”
condition.
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As the government sought to increase the utilization of northern forests, policies were
introduced to encourage the use of the under-utilized hardwood resource. Royalties to
the government for the harvesting of hardwoods were kept to the minimum (currently
50c/m3 for aspen) to encourage their use, a policy that worked extremely well in
developing the utilization of economically marginal conifers and in developing the forest
industry in the southern interior in the 1960’s and 1970’s. With no royalties, no
stumpage allowance for aspen silviculture was established, the assumption being that no
silviculture investments were needed. Aspen would always come back after logging.
Thus, no cost allowances for logging and silviculture are provided in hardwood stands,
whereas costs of harvesting and management of conifer stands (or for the conifer
component (based on basal area) of mixedwood stands) are deducted from the conifer
stumpage payable to the government.
Under such a policy, a logical strategy for a licensee might be to promote pure hardwood
stands close to the processing centers (mills) and conifer stands in the remote areas. The
higher costs of long log hauls of spruce are deductible from stumpage and are thus paid,
in part, by the government, while the haul costs for hardwoods, paid by the licensee,
would be minimized. Because this is a consequence of this stumpage policy, and because
there is a lack of specific spatial objectives for the dispersal of conifers and hardwoods
across the larger landscape in higher-level plans, a licensee cannot be faulted for adopting
such a strategy. This is particularly true because past fire history has resulted in large
areas of the Ft. Nelson landscape being dominated today by hardwood stands, and other
large areas being dominated by conifers, creating a natural precedent for such
concentration. However, such practices, driven by stumpage policy, will definitely tend,
over a long period of time, to further “un-mix” the boreal mixedwood landscape, but in
this case at a larger landscape scale in comparison to the stand scale “unmixing”
discussed above. Also, this policy would tend to maintain such a landscape pattern
whereas in unmanaged forests the present areas of species concentration would change
over time as a result of succession and subsequent disturbances. Clearly, there is a need
for explicit landscape objectives in higher-level plans, and for a stumpage policy that
would put aspen and spruce on an equal footing.
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2. The Current Issue: How much understory spruce should
be protected?
With the increase in environmental concern and public interest in forests and
ecosystem management, the natural disturbance paradigm has become a model for
forest management, especially in the frequently disturbed boreal forest. This
paradigm suggests that management should sustain the “natural” landscape condition
that existed prior to the influence of “western” or “industrialized” societies. The
spatial patterns and frequencies of disturbances of different size and severity, and the
diversity of different “structures” (standing live, standing dead and downed trees) left
by historical disturbance regimes should be emulated to some degree. Interestingly,
while “ecosystem management” and “naturalistic” forestry is advocated by some
groups in society, the current Forest Practices Code and tenure systems pose
constraints that make such innovative and environmentally interesting changes in BC
forestry virtually impossible. Also, the more the public learns about the
environmental and social consequences of natural disturbance, the less desirable an
unfettered emulation of natural disturbance becomes as a management objective. The
lack of appropriate policy, regulation and institutional arrangements lie behind many
of the issues we face in BC forestry today, and it appears that this is the case in this
boreal forest management issue as well.
2.1 Understory spruce protection on PA 14: the Ministry of Forests’ position.
The combination of these considerations has resulted in instructions by the Ministry
of forests to Slocan Group, Fort Nelson Woodlands, to increase the protection of
spruce understory in a portion of the hardwood-dominated stands in their Pulpwood
Agreement 14 in order to:

sustain the landscape balance of pure deciduous hardwood and deciduous
hardwood leading stand types within the PA area, and maintain the overall
balance of pure deciduous, deciduous leading, conifer leading and pure conifer
across the entire landscape managed jointly under Slocan’s Pulpwood Agreement
and Softwood Forest License.

sustain the biodiversity and wildlife values that may be associated with having old
spruce growing in developing aspen stands that may not be provided by young or
smaller spruce regenerating under the developing aspen canopy.

sustain the biodiversity and wildlife values that may be associated with having
intimate mixtures of spruce and aspen, and may not be provided by aggregated or
“clumped mixtures” or by “co-managed” aspen/spruce in patches.

provide an increase in softwood volume when the mixedwood stands are
harvested in the future, and shorten the time to harvestable size for spruce by
retaining the 15 – 35 years of spruce growth generally represented in the 2 – 7m
tall spruce understory.
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As a guideline for spruce understory retention, the Ministry of Forests has
suggested to Slocan Group, Fort Nelson Woodlands that any stand in which there
are more than 400 well-distributed spruce 2 – 7m tall per hectare in the understory
should be harvested in a manner that retains a significant proportion of this
understory. It is expected that about half of these spruce will survive the harvest
operation and subsequent losses to wind or insects. This understory protection
only applies if the spruce have good vigour, are acceptably free of diseases, and
have the potential to resist windthrow and to respond in height and diameter
growth to release. Aspen windbreaks may be required in order to avoid wind
damage to released spruce. Where there are more than 700 well-spaced, 2 – 7m
spruce, harvesting should be delayed until harvesting methods are developed that
can protect this spruce component. Where the spruce understory is taller than 7m
and constitutes more than 20% of the stems in the stand, harvesting should be
delayed to allow the conifers to become a merchantable component of the stand.
This requirement to protect understory spruce may be over-ridden in certain cases.
For example, where “superior” aspen growth potential exists either due to
superior genotypes or to superior aspen growth conditions, the stand may be
treated as a pure hardwood type and no investment need be made to protect the
spruce.
Where spruce understory retention is expected to cause a deviation from the
existing local landscape and PA area balance of conifer-leading (CD), deciduous
leading (DC) and deciduous (D) stand types, or the existing overall landscape (PA
plus FL) balance of conifer (C), CD, DC and D stand types, the understory spruce
retention requirement may be relaxed. The Licensee is not obliged to replace a
particular pre-harvest stand with exactly the same stand type, as long as the
overall landscape ratios of C (>80% conifer), CD (79-50% conifer), DC (49-20%
conifer), and D (<20% conifer), are maintained. As a particular stand type is
converted to another type, the ratios are maintained by “trading” for other stands
that are converted in the opposite direction. This trading is also driven by the
principle that there will be no increase in the costs of mixedwood management as
a result of understory spruce protection, and by the stumpage policy that fails to
give a stumpage allowance on the aspen management. The silvicultural cost
allowance given for the spruce-leading stand that is converted to a deciduous or
deciduous-leading stand is supposed to compensate for the additional harvest and
stand tending costs of protecting spruce understory in a deciduous or deciduousleading stand for which there is little or no cost allowance.
2.2 Understory spruce protection on PA 14: the position of Slocan Group, Fort
Nelson Woodlands.
The Slocan Group, Fort Nelson Woodlands has challenged the MoF instruction on a
number of grounds:
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
the protection of understory spruce can increase logging costs by as much as
$1,500 ($1200 was noted as a probable average) and the company is not
convinced that this will result in a comparable increase in stand net present value.
The Licensee feels than an economic assessment of the probable outcome of
understory protection should be conducted for each proposed understory retention
stand as part of the understory protection decision process.

the shortness of the winter harvesting season, from freeze-up to spring breakup,
can be less than 100 days. Understory protection can increase the time to harvest
a given volume by 25 – 30% (with comparable increases in logging costs). With
experienced operators the extra time and cost would be reduced, but the contract
personnel of Fort Nelson tend to be transitory, with a significant proportion every
year being on the steep part of the “learning curve”, so these time and cost
increases are not declining. The additional time means that the company may be
unable to harvest the 1 million m3 each year that is needed by the mill. If climate
change causes a further shortening of the harvest season, this problem will get
worse. The requirement to leave 15 – 25% of the aspen overstory for wind
protection results in forgone hardwood volume and associated social values (the
windbreak aspen are not expected to be recovered at a later date), and a larger
area to be harvested to achieve the desired total hardwood harvest.

the Licensee believes that the objective of maintaining the balance of stand types
in the PA and the (PA & FL) landscape can be achieved more economically and
cost effectively by the combination of a lower level of spruce understory retention
than proposed by the Ministry of Forests (a smaller area on which retention is
practiced, rather than a different “trigger” level of understory to indicate
retention), and the use of silvicultural strategies (e.g. planting spruce, herbicides,
manual brushing) to co-manage even-age aspen and spruce under a variety of comanagement options. The criteria for understory retention proposed by the
Licensee is 600 total stems per hectare. However, the licensee would not act to
protect the spruce on every stand that is a candidate by their criterion. They
propose to protect spruce regeneration on 300 ha of the 1500 ha of deciduous
stands that are harvested each year in PA 14. Forty percent of this 1500 ha (i.e.,
600 ha) has > 600 spruce understory. Of this 600 ha, some may be classified as
“superior” aspen and excluded from understory protection. Consideration of the
health and vigor of the spruce understory may remove eligibility from other
stands. If more than 300 ha remain eligible for understory protection in any year,
the licensee undertakes to protect understory spruce on the best 300 ha. If less
than 300 ha remains eligible in any one year, the Licensee will only protect spruce
on that area In the current planning year, only the best 50% of the area with
eligible spruce understory will be targeted for understory protection; i.e. 300 out
of 600 ha.. Of the 500 ha of DC stand types in the annual cut, 25% or 125 ha will
be managed as an intimate mixture. The remaining 75% will be “unmixed” to
some extent through one of several spruce-aspen “co-management” options.
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
Restrictions on the use of herbicides, lack of employable people to do manual
brushing, and the cost and difficulty of access for hand brushing limits the area
that can be brushed, thereby limiting the area on which active management for
spruce in intimate mixtures can be undertaken. Where regrowth of aspen is
expected to be very vigorous, retaining understory spruce is not expected to result
in a harvestable crop without herbicides or brushing, especially since severely
suppressed spruce appears to show very delayed growth response to harvest
release on many Fort Nelson sites. This limits the Licensee’s ability to manage
intimate mixtures of spruce and aspen and requires them to simplify the
management of these stands through one of several “co-management” options that
would reduce the intimacy of the mixtures.

Growth response by released understory spruce has been slow and disappointing
in the Fort Nelson area. Part of this may be due to the denser and taller overstory
aspen canopy in comparison to boreal forests to the east in which understory
spruce has shown earlier and more promising release growth. With the vigorous
root sucker growth that characterizes aspen in the Ft. Nelson area, the Licensee
feels that only the healthiest spruce will remain thrifty, and that wind and
defoliator damage will frustrate their efforts to maintain intimate mixtures through
understory protection in many cases.
The failure to achieve agreement between Slocan Forest Products Ltd. and the
District Ministry of Forests staff led to the issue being transferred to the Prince George
Regional office. I was requested to moderate a discussion between the Ministry of
Forests and Slocan to find a basis for agreement, and, in the eventuality of failure to reach
agreement, to submit an opinion to Mr. Ray Schultz, Regional Manager, Prince George
Region, concerning acceptable mixedwood management strategies for PA14. Because no
agreement was reached following an August 1999 field trip, a December 1999 meeting
and a March 2000 meeting on the critical question as to how much of the area that
satisfies the 600 spruce understory criteria (MoF is seeking active retention on most or all
of the stands that meet the criteria; the Licensee is seeking to work on 300 ha of this area)
should have understory protection, the issue was passed to me for the opinion expressed
in this report. It should be noted that agreement between MoF and the Licensee was
reached on most other technical points.
3. Recommendations
3.1 Premises from which the recommendations are developed:

Unless considered at a scale of a million hectares or more, there is probably no fixed,
stable ratio of C, CD, DC and D stands in the Fort Nelson landscape. At smaller
scales the ratios will be continually changing as a consequence of natural disturbance
and post-disturbance succession.
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






Relative to the effects of fire, wind/snow and insects, forest harvesting has a small
impact on the stand type ratios at the large landscape scale. It can have a significant
effect at smaller, local scales, as does natural disturbance.
In the absence of higher-level plan objectives for a desired local and regional
landscape pattern of different stand types, the existing local landscape pattern is a
reasonable interim guide as long as the dynamic nature of the pattern at smaller scales
is recognized. However, there is an urgent need to develop these higher-level plan
objectives.
In the absence of an acceptably accurate landscape inventory of stand types and
spruce understory conditions, it is premature to set rigid targets for the desired extent
of different stand structures and the acceptable dispersion and different degrees of
aggregation of understory spruce within mixedwoods. “Adaptive management” is
clearly an essential component of management of boreal mixedwoods until there is a
much improved inventory and ability to forecast stand development patterns.
Adaptive management precludes rigid a priori regulations, other than very short term
guidelines as a basis for proceeding until management theories and models have been
adequately tested and validated.
In the absence of accurate, spatially-explicit inventory data on the proportions of
understory spruce in different aggregation classes, and in the absence of research
results identifying the biodiversity values over the life of the stand associated with
different degrees of aggregation, it is difficult to defend any particular policy with
respect to the desired patterns of aggregation. While there may be growth and yield
advantages of intimate mixtures, I was not presented with empirical evidence on this
matter, and the modeling results we were shown, though very useful for the purposes
of the discussion, are far from conclusive considering the capabilities of the model
being used to represent complex stand structures.
The concept of “trading” is a useful way of providing flexibility in the face of risks
and uncertainties concerning the stand composition and structural outcome of a
particular harvesting event. Defoliators, diseases, wind and the consequences of the
logging are sufficiently difficult to predict that there is currently considerable risk
attached to forecasts of what stand type will develop, especially considering the type
of stand growth models the Ministry of Forests has been using.
The short winter harvesting season and the shortage of employees to undertake
certain types of silvicultural work place practical constraints on the management
choices that can be made. A balance must be sought between these practical
constraints and environmental objectives.
The above considerations notwithstanding, maintaining some level of intimate and
aggregated mixedwoods in the Fort Nelson landscape is an appropriate objective,
considering the “precautionary principle and the “coarse filter” approach to
conservation issues. The question is: what should the level be, and is there any
natural precedent for any particular level? If there is a natural precedent, is it a fixed
level or does it change over time? What is the large landscape spatial pattern of this
precedent, and what is the range of small-scale patterns within the large landscape?
3.2 What is a “mixedwood”? When is a mixedwood not a mixedwood?
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Possibly the most fundamental issue in this discussion is: what is a mixedwood?
This may appear to be a trivial question, but it lies at the heart of the issue. Until one has
an ecologically based definition, the questions of how to manage to sustain mixedwoods,
how much constraint should be placed on harvesting, and how much economic
investment can be justified to achieve mixedwood objectives cannot be answered in a
logical manner.
The problem of definition is one that has plagued forestry in BC over the past few
decades. What is “old growth”? What is “biodiversity”? What is “clearcutting”? What
is “sustainability”? Until there is a clear, site-specific, forest type-specific, ecological
sub-zone-specific and ecologically-based definition of these terms, one cannot know how
much one has, where it is, when you do not have it, and how to develop policy with
respect to the issues surrounding each of these terms.
In their recent decision to replace clearcutting by various renditions of “variable
retention” silvicultural systems, Weyerhaeuser (then MacMillan Bloedel) adopted the
definition of clearcutting that I offered some years ago in my essay in the journal
Environmental Reviews. I suggest a similar approach to the ecological definition of
boreal mixedwood:

A boreal mixedwood is a stand-level concept in which the mixture of species (in
this case mainly white spruce and aspen) is such that 50% or more of the stand
area is in the ecotone between the constituent species”
The ecotone is the area over which each species, or each individual of each species,
exerts influence on the physical (light, temperature, wind, humidity), chemical (soil
chemistry, soil fertility), and biological (plant, animal and microbial) conditions
experienced by the other species. This “species influence” is usually at its maximum
close to an individual tree or stand edge, and declines with increasing distance from the
individual or stand edge, usually in an exponential manner. The influence is a function of
shading, reduction in wind speed, moderation of temperatures, litterfall, seed dispersal,
root extension, and any spatial relationships that wildlife may have with the trees in
question.
According to this definition, a boreal mixedwood can range from an intimate mixture of
spruce and aspen (for example), to a patchwork of monoculture “min-stands”, as long as
the ecological influence of each species is affecting 50% or more of the area occupied by
the other species. This definition implies that a clumped pattern is every bit as much a
mixedwood as an intimate, tree-by-tree pattern, albeit with a different spatial arrangement
of the biological resources and ecological microsite conditions.
Definition of the ecotone area should be based on an ecotone evaluation in the latter part
of the rotation. Clearly, the extent of the ecotone in young stands, even with intimate
mixtures, will be small as the ecotone is generally a function of tree height. Because of
the lack of a complete rotation-length chronosequence of stands with all levels of
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aggregation, this evaluation will have to be undertaken using spatially-explicit, ecosystem
management models.
The question as to how many tree heights the ecotone extends out from a stand edge or an
individual tree is a complex one. It depends on slope and aspect, on canopy width and
density, on foliage retention (which controls litterfall and thus the area of soil
significantly affected by litterfall), root extension and the regional and local climate
(cloudiness, wind and frost). Ecotone extension at a solid stand edge will be different for
stands of different stocking density and canopy closure, and different from that of
scattered individual trees. It will be different between open grown trees and stand grown
trees isolated by harvesting. This is an area of research that has been largely neglected in
the past and is now receiving some attention, but in which more field data and ecosystem
modeling is needed if we are to be able to answer questions about mixtures from an
informed, scientific basis. In areas with low sun angle (northern forests), the
microclimatic ecotone may extend much further on the northern side than on the southern
side (in the northern hemisphere).
Considering the character of the northern forest, an average ecotonal area of 1 – 1.5 tree
heights may be reasonable for dense stand edges, but perhaps only 0.5 – 1 tree height for
isolated individual trees. We do not at present know how to define empirically the
ecotone of tree clumps of various sizes, densities and tree heights, but appropriate
modeling could give us an improved understanding of this. Definition of mixedwood
requires the calculation of the degree of ecotone overlap between the component species
in the mixture. If the ecotones overlap on 50% or more of the area in question, then from
an ecological standpoint it is a mixedwood. If less than 50% overlap, it is a mosaic of
monoculture patches, that may be considered to be a mixture when considered at a larger
spatial scale, but not in terms of local stand level ecological processes. The definition of
mixedwoods thus cannot be defined simply in terms of the numbers of each species in the
stand. It depends also on their relative sizes and spatial arrangements.
There is an urgent need to use spatially explicit ecosystem management models that are
able to satisfactorily represent all the major components and process of the ecotone in
order to arrive at an ecologically-based assessment of when a mixedwood stand is a
mixed wood ecologically and when it is not.
It should be recognized that the definition I have proposed here is plant and ecosystem
process – based. Ecological definitions of mixedwoods in terms of wildlife habitat may
vary, and will vary between different types and species of animal. A separate analysis of
what a mixedwood is for each of the major guild of wildlife would be necessary in order
to define mixedwoods in terms of the ecology of each animal species of interest. My
definition might thus be considered a coarse filter approach.
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3.3 Are we shackled in our thinking about the boreal forest by a regulation-based,
“designed forest”, and a southern and possibly coastal perspective on forestry?
The dense, sometimes monoculture, post-fire and post-windstorm conifer stands that
characterize many forests at low and medium elevations in the southern interior and
southern coastal areas have definitely influenced silviculture policy in BC in the past.
Uniform spacing and dense stocking were definitely de rigueur in silviculture in these
southerly conifer forests in the 1960-1980/90 period, as was the control or even
elimination of non-commercial deciduous hardwoods. “Conifers are good, deciduous
“weed” species are bad” was the marching order of the day. These silvicultural concepts
were the foundation of MacMillan Bloedel’s “Designed Forest” concept of the 1970’s
(now abandoned). This philosophy continues today in concepts such as stocking
standards and free-to-grow regulations, notions that were introduced as a consequence of
the undesirable outcomes of relatively unregulated forest exploitation that left large areas
of forest in a depleted, unhealthy and “unsustainable” condition. The fact that allowable
timber harvests are still based largely on growth and yield models designed for even-aged
monocultures supports this interpretation of BC forest history.
Clearly, there was a need in the past for management objectives, guidelines and
regulations to pilot the transition from the exploitation phase to the “administrative” stage
of forestry. The failure of the latter stage to respect the ecological and biological
diversity of our forests and to achieve social and environmental objectives led to the
ecologically-based stage. As changing public preferences with respect to forests
expanded the range of values and environmental services desired from forests, the purely
ecologically-based stage is now giving way to the “social forestry” stage.
Forestry in BC is somewhere between the Administrative-Ecologically-based transition,
and the Ecologically-based-Social forestry transition. There are still some forest policies
that are administrative rather than ecological in nature. There are still some polices that
are ecologically based but do not achieve a balance between the many different
ecosystem values desired by society. As we consider how boreal mixedwoods should be
managed, we must do so in the context of this evolution, and make sure that we leave the
regulation-based, administrative approach behind in favour of respecting how particular
forest ecosystems function, and how to manage them to sustain a variety of social and
environmental values. We must learn how to balance the sometimes competing and
conflicting demands of aesthetics, poorly founded and often untested theory, the ecology
of the desired future values, and operational and environmental constraints.
Implicit in this transition to social forestry is the recognition that “sustainability” and
“biodiversity” are landscape concepts, not stand-level concepts, that the boreal is a multidisturbance type landscape, that landscapes in the boreal are of the order of millions of
hectares, not the tens of thousands or hundreds of thousands of hectares that constitute
landscapes in more southerly areas of the province, and that the variation in structure and
species composition forms an almost continuous “continuum” between the extremes.
Above all we must avoid any tendency to apply concepts that were designed for, and may
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be relevant in, forests of different ecological character elsewhere in the province or
Canada.
A final note in this section: the boreal forests seen around Fort Nelson appear to be
significantly different from boreal forests seen in Alberta and Saskatchewan. While the
experience from these other provinces will unquestionable provide useful guidance, this
experience must be interpreted in the light of ecological and biological differences
between Fort Nelson and these other boreal locations.
3.4 Recommendations.
3.4.1 Definition of “mixedwood”.
Because the entire issue under discussion revolves around maintaining the
character of boreal mixedwoods, there must be a quantifiable, ecologically based
definition of what a mixedwood is.
The discussion of spruce understory retention to achieve “intimate” mixedwoods
is confounded by the question as to what a mixedwood is, when a “mixedwood” is not a
mixedwood, and when a mixture is “intimate” or not. At what spatial scale of
aggregation has a mixedwood been “un-mixed”? At what scale is it still a mixture, but
not an intimate one? There appears to be a preoccupation with intimate mixtures as
opposed to clumped mixtures, with very little empirical evidence regarding growth and
yield and biodiversity implications of this small-scale spatial pattern.
Recommendation #1. The MoF should, without delay, select an operational and
quantifiable definition of “mixedwood”. This should be ecologically based, and founded
on the concept of the ecotonal effects of mixtures. It is recommended that any stand with
50% or more of its area in a mixed species ecotone should be considered as a
mixedwood. This concept should be explored and refined using spatially explicit,
ecosystem management models that can simulate the “ecological footprint” of an
individual tree or group of trees. The importance of acquiring this definition is that it will
contribute to a resolution of the issues of aggregation. The MoF in cooperation with the
Licensee should undertake a much more sophisticated modeling analysis of the short term
growth and yield implications and the rotation-on-rotation implications of different
dispersion/aggregation patterns, and a review of the research literature be commissioned
to assemble what is known of the biodiversity and wildlife implications of different small
scale stand patterns.
3.4.2. Landscape ratios of C, CD, DC and D stand types.
In the absence of accurate inventory information and large landscape modeling of
possible future changes in these ratios as a result of ecological succession and natural
15
disturbance, the present local landscape ratios based on the existing inventory and on
cruise data provide a reasonable interim guide for “trading” different stands over the next
5 years. However, this is not an adequate basis for planning in the long term.
Recommendation #2. That MoF undertakes an extensive large landscape
analysis of both the present ratios of stand types, and of how these ratios may change
over time as a result of succession and possible future natural disturbance scenarios. This
analysis is presumably an essential component of defining desired future forest
conditions in LRMP and LUP processes.
3.4.3. Possible consequences of “trading” for landscape pattern and stand
pattern.
There is a legitimate concern that current stumpage policy and the “trading”
concept could alter regional dispersions of different stand types, just as succession and
disturbance can alter such dispersions.
Recommendation #3. That MoF establishes as soon as possible through the
LRMP and LUP processes a target landscape dispersion pattern that reflects the
desirability of allowing sites to progress through different seral stages, the fact that
natural successional processes will alter this pattern over time, and the fact that different
landscape-level management strategies and fire control polices will also result in different
patterns.
3.4.4. Acceptance of a continuum of small-scale spatial pattern rather than the
single concept of even spacing.
Given that boreal mixed stands exhibit a wide diversity of dispersion patterns;
given that we lack good long-term empirical evidence of the implications of different
dispersion patterns for many values; given that the practical constraints of the short
harvest season and the additional time requirements of harvesting to achieve intimate
mixtures through understory spruce retention may prevent the allowable cut from being
harvested; given that clumped understory spruce may be more windfirm than dispersed
small spruce and may make harvesting easier and less expensive; and given the
restrictions on the use of herbicides, the problems of summer access and the limitations
on costs and human resources needed to maintain intimate mixtures and uniform
dispersion of spruce and aspen in even aged stands, why not assess the efficacy of
moving away from the even spacing concept?
The Licensee and the MoF both agree that 600 stems per ha of understory spruce
should be the eligibility criteria for understory spruce protection. The question remains as
16
to whether there should be a dispersal criterion, such as 400 well spaced stems as
suggested by the MoF.
If a stand has > 600 stems per ha but they are arranged in clumps of three, a
criterion such as 400 well spaced stems per hectare would result in the stand being
rejected as a candidate for understory protection. Yet, such stocking and clumping may
well produce a significant volume of spruce by the end of the rotation. Thus, the concept
of well spaced regeneration that may be valid for monocultures, or even for mixtures, in
some of the forests in BC may be very questionable for boreal mixedwoods and contrary
to the higher objective of retaining a significant component of spruce in hardwood
dominated stands.
Recommendation #4. That the MoF explore ways of modifying the criteria for
understory retention for mixedwoods to accept a higher level of spruce aggregation than
currently accepted – one that would facilitate the operation and economics of harvesting
while retaining a significant component of understory spruce, and would facilitate the
management of even-aged mixtures. I recommend against the introduction of a well
spaced criterion for understory spruce protection at this time, and until the question of the
rotation-length growth and yield consequences of aggregation has been resolved.
Unfortunately, it would take many decades to collect empirical evidence on this question
from long-term growth and yield plots, and chronosequence or retrospective studies are
difficult to undertake in a convincing manner when there has not been a long history of
different harvesting patterns to learn from. This leaves the use of growth projection
models. It is recommended that further investigations of this issue be undertaken with
TASS building on the useful work in this respect by Lorne Bedford and the MoF
modeling group (led by Ken Mitchell and Jim Goudie), but that this valuable contribution
be complimented with the use of truly ecosystem management models that can assess the
growth implications of clumping on a more biological basis.
Rather than requiring a higher % of the stands that satisfy the understory retention
criterion than the Licensee asserts is practically possible, it is recommended that the
Licensee’s proposal to target 300 ha of understory spruce protection per year (in 2000
this is 50% of the candidate stands of 600 ha) in stands that have > 600 total stems per ha
be accepted, but that in addition a requirement be developed to retain clumps of vigorous,
well developed understory spruce in stands that have less than 600 stems of understory
spruce per ha in a way that minimizes additional harvest time and costs, but maximize
spruce protection. This would achieve both the Licensee’s proposed practical maximum
of retention, and move a considerable way towards the MoF’s desire to retain more
spruce while not increasing overall costs.
Similarly, the Licensee’s proposals for co-management that increase spruce and
aspen aggregation in order to simplify silviculture and reduce silviculture costs should be
accepted, subject to the analysis of the co-management proposals in terms of their
ecotonal area, so that the desired % area in mixedwoods is retained.
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Over the next 5 years, the MoF and the Licensee should experiment and
cooperate to explore how this would work, what levels of additional understory spruce
retention this would achieve, how co-management would act to retain aggregated
mixedwoods, and what the implications would be for growth and yield and other (e.g.
biodiversity) values. Learning by doing (adaptive management) is the correct approach
given the considerable uncertainties involved, but this should be complimented by
modeling because experienced-based solutions will require much longer than we wish to
wait for the answers. Many different harvest patterns should be tried and both monitored
and modeled. The next 5 years should be a truly adaptive management period with the
specific objective of developing a set of quantifiable, monitorable but flexible guidelines
for adoption at the end of the period. Operational conditions during this period should be
such that it is possible for the Licensee to conduct its activities in an economically
efficient manner, but considerable responsibility should be put on the Licensee to
continue to develop new and innovative approaches to achieving the spruce protection
and stand composition/structure objectives. The MoF should expect leadership from the
Licensee in this respect.
3.4.5. Adjustment of the area of deciduous forest in which spruce understory is
to be protected.
The discussion between the Licensee and the MoF dealt mainly with the figures
that were available for the year 2000 and operational experience over the past few years.
Because of changes in technology, operator experience and capability, climate, labor
relations and other factors that can be anticipated, but not accurately predicted, in the
future, there should be flexibility on the part of both the MoF and the Licensee with
respect to the 300 ha of understory spruce protection that was proposed by the licensee.
Recommendation #5. If operator experience and/or new harvesting techniques
and equipment results in future reductions in the additional time and $ costs of understory
spruce protection in deciduous stands, the MoF should require the Licensee to protect
proportionally more than 300 ha of understory protection. If there are less than 300 ha of
eligible stands in any one year, the difference between the area protected and 300 ha
should be carried forward to the next year. If operator efficiency improvements and
weather permit, the unprotected area should be made up in that following year, or the
untreated area equivalent should be carried forward to future years. By the same token, if
climate change shortens the field harvesting season, or if labor difficulties or other
situations out of the hands of the Licensee prevent them from achieving the target 300 ha,
this should be accepted, again with the unprotected area being carried forward to the next
year as suggested above. The % achievement of the 300 ha spruce understory protection
would be re-evaluated at each 5 year Timber Supply Analysis. All these suggestions are
subject to future decisions with respect to higher level plans, and to the realities of
climatic and operability limitations.
In defining the area on which spruce understory has been protected, the area
should be based on the actual area of land on which spruce has been protected. This will
often be less than 100% of the cutblock area on which there is > 600 stems per ha spruce
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understory, because of uneven dispersal of the understory spruce. By the same token, the
licensee should be able to count areas of spruce understory protected in cutblocks that
have <600 stems per ha, and this area should contribute to the achievement of the 300 ha
per year target.
3.4.6 The question of the area of DC stands that are to be managed as an
intimate mixture rather than being “unmixed” into a co-managed patchwork of pure
spruce and aspen patches.
The proportion of the DC mixedwood type that should be managed as an intimate
mixture is an important one. It has implications for landscape pattern, for any values that
may differ between intimate mixtures and patchwork mixtures, and for silvicultural costs.
The proposal by the Licensee is to manage 125 ha of the annual DC cut as an intimate
mixture. This is 25% out of the 500 ha of DC forest they will log in 2000. Should the
Licensee be required to always manage 25% as intimate mixtures irrespective of the area
of DC logged in one year? Or should their proposal for a 125 ha maximum of intimate
mixture management each year be accepted? Should a fixed % or a maximum area be
implemented each year irrespective of the spatial distribution (i.e. the intimacy) of the
mixtures in the area being harvested? Would such a policy reduce the landscape diversity
of species patterns, and would this be good or bad if it did? Given the mutually agree
principle of no net increase of delivered wood costs, would the extra costs of requiring a
higher level of intimate mixture management be a better option than some other
requirement that also increased costs, such as the area of understory spruce protection in
deciduous stands?
In the absence of a better definition of “intimate”, and in the absence of better
information on the frequency distributions of stands with different degrees of intimacy in
the Ft Nelson landscape, and on how these distributions may vary across the landscape
and over time, any decision on this issue at this time would necessarily appear to be
arbitrary. Part of the answer lies in a better understanding of what an intimate mixture is
and what are the values it offers that are not adequately provided in the various types of
proposed co-management of spruce and aspen. This improved understanding will require
a synthesis of what is already known, additional field studies, and spatially-explicit
ecosystem management modeling as suggested below.
Recommendation #6. I recommend that the Licensee’s proposal for 125 ha of
intimate mixture be accepted for now. I was not presented with evidence that would
convince me to conclude that this number is good, bad, too high, too low, or just right. In
the absence of such evidence, management should proceed on the basis of this proposal,
but the MoF and MoELP should jointly commission a process by which the values,
objectives and definitions by which this significant question can be moved from an
arbitrary to an objective and data-based decision-making environment. I am in no way
recommending that 125 ha of intimate mixtures is the correct target area. I am
recommending that a process be established whereby a rational, databased evaluation of
its suitability can be made.
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3.4.7. Assessment of the wood fibre quality implications of different mixedwood
strategies
Open-grown conifers have longer live crowns, larger branches, wider growth
rings and more juvenile crown wood than the same trees grown in closed, even-aged
conifer stands. Scattered individual spruce in boreal mixedwoods are not the same as
open grown spruce because of the competition from the deciduous hardwoods, but they
do share the character of longer live crowns. They tend to be intermediate between open
grown and closed conifer stand grown trees. This has implications for spruce wood
quality. Mixedwoods may also have implications for aspen wood quality.
Reccomendation #7. As a part of the development of the mixedwood policy, the
MoF should, in conjunction with the Licensee, investigate the issue of the implications of
different mixtures and stand structures, and especially different degrees of spruce
aggregation, for wood quality. Are there wood quality advantages or disadvantages of
aggregated rather than dispersed spruce growth.
3.4.8. The issue of stumpage for hardwoods.
The lack of stumpage and cost allowances against stumpage for hardwoods leads
to the risk that “trades” could restructure stand type mixtures across the larger landscape.
Whether or not this is desirable must be based on the analyses recommended under 3.4.2
and 3.4.3. Whichever is the case, institutional arrangements are needed to ensure that the
MoF’s higher level objectives are fulfilled.
Recommendation #8. That the MoF examines the stumpage policy with respect
to hardwoods, and considers revisions that would allow costs for hardwood management
that would achieve the higher-level landscape pattern and other objectives.
3.4.9. The need for spatially-explicit ecosystem management modelling at the
stand level and the local landscape level.
The best guide for silviculture is usually appropriate field experience. Computer
models cannot at present deal with the full complexity of complex stands. However, in
many forests we lack the appropriate experience, such experience will take many decades
to acquire, and there is a new generation of complex stand structure, ecosystemmanagement models that do have the capability to explore many of the key issues.
Where these models are strongly based on empiricism (and incorporate the growing body
of empirical field trial results), but also incorporate sufficient ecological process
simulation to address critical management issues, they offer a valuable additional
decision support tool for issues such as mixedwood definition and the evaluation of
alternative mixedwood management scenarios.
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Recommendation #9. That the MoF undertakes a technical modelling
workshop to examine in detail the recent genre of succession and ecosystem management
models, and to evaluate their efficacy as additional tools in the complex task of designing
and implementing sustainable boreal mixedwood management. Where shortcomings of
such models are identified, the MoF should undertake, perhaps through FRBC, to
develop promising candidate models to give them the desired forecasting capabilities.
These capabilities should be defined jointly by MoF and the Licensee. There will be an
international conference on forest modeling at UBC in August 2001. It is recommended
that MoF and Licensee representatives attend this, with a follow-up more technical model
evaluation workshop in the fall of 2001, if it is not held before then.
3.4.10. Utilization of complex stand, ecosystem models to explore alternative
stocking standards, and understory protection policy.
Until we have the 50-year results of operational and demonstration field trials, we
cannot be confident of the success of any policy we put in place. Adaptive management
requires a priori modelling of the management system in question, the making of
forecasts, and the comparison of these forecasts with stand monitoring information.
Because adaptive management appears to be essential in the boreal mixedwood, so also is
ecologically based modeling to prepare ecologically based forecasts.
Recommendation #10. Following the modeling workshop, the MoF and the
Licensee should work in a partnership to undertake adaptive management modelling
using the selected model(s), or the further development thereof, the results of which, in
conjunction with research and field trial results, will lead over time to the refinement of
policy and practice. Interim regulations should be established based on a combination of
practical field experience, field research trials and this modeling activity. This modeling
activity should be an explicitly recognized component of the 5-year period of exploration
and adaptive management proposed above.
3.4.11. Evaluation of the release growth potential of the understory spruce.
The slow growth response of understory spruce to overstory aspen removal raises
the question of our ability to operationally judge their release potential prior to harvest.
Unless a fairly reliable method of judging release potential is available, understory
retention efforts will have a high risk of failure. Spruce budworm damage may be a
factor in the poor growth response in some cases. A better understanding of release
growth is needed for believable scenario modelling.
Recommendation #11. The MoF should work with the Licensee to develop and
test field methods of understory spruce assessment that are reliably related to release
growth potential. Existing methods do not appear to be sufficiently well based on tree
physiology and the ecology of production. Systems that estimate leaf area or crown
volume rather than simply green crown length should be tested. The results should be
incorporated into decision support tools.
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3.4.12. Stratification of mixedwood blocks and their classification as operatorselection understory spruce clump retention vs. designated trails and wind buffers.
I was asked to comment on the current practice in the Fort Nelson District for
50% of the of the eligible spruce understory retention stands to be managed as designated
trail harvest areas with wind buffers vs. operator avoidance of understory spruce and
retention of spruce in wildlife tree patches.
Prior to any harvest there should be careful site assessment and the stratification
of the site into sub-areas in which spruce understory retention is a sensible option, areas
where it is not, and stands in which the understory spruce is so widely and uniformly
distributed that carefully planned designated trails and wind protection aspen strips is the
appropriate harvest and silvicultural system. The site and the existing understory spruce
dispersion, abundance and vigour should be the deciding factors as to whether operator
avoidance, wildlife tree patch retention or designated trails will be the system of choice.
Recommendation #12. Stratification of cutblocks and the decision of which
understory protection system is to be used to fulfill the Licensee’s commitment to
understory spruce protection should be decided by the forest condition following site
inspection, and by consideration of all the other cutblocks in that year. The decision
should not be made cutblock by cutblock in isolation from the overall management
objectives for the year. Where a stand has high potential for understory protection but
agreement between the MoF and the Licensee as to how it should be managed cannot be
reached, that cutblock should be deferred in favour of harvesting stands with very low
spruce understory potential until a mutually agreeable system can be devised. Where no
agreement can be reached and the Licensee feels obliged to harvest the stand,
independent arbitration of the issue following on-site inspection should be undertaken.
4. Conclusions
4.1 The dynamic nature and high spatial variability of the boreal forest requires a flexible
system of management in order to achieve specific landscape-level objectives.
Management of the wide variety of stand types, many of which will change to another
stand type with or without management, lends itself to management by objectives more
than management by regulation. Our relative lack of knowledge and experience of
managing these northern forests suggests an adaptive management rather than a
regulation-based approach. However, until appropriate objectives are developed, it is not
surprising that the MoF has been obliged, in order to fulfill its mandate, to fall back on
regulation. This is not satisfactory, however, and it is incumbent on the stewards of the
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public lands, the MoF, to develop appropriate objectives and definitions so that the issues
that are the subject of this report can more easily be resolved.
4.2 Objective-based management requires a specific statement of what the objectives are
in terms of stand level and landscape level pattern and temporal dynamics. Adaptive
management to achieve these objectives requires forecasts of ecosystem behavior against
which stand and landscape monitoring will measure achievement of anticipated
outcomes. Preparation of these forecasts requires the use of ecosystem management
models rather than conventional growth and yield tree population models. Many of the
issues in this report are irresolvable in the absence of a much longer period of experience
than we have and can therefore only be dealt with in an arbitrary manner unless the issues
are explored using spatially-explicit, ecosystem management models at both the stand
and landscape levels.
4.3 The practical limitations imposed by the short logging season, the scarcity of skilled
and experienced equipment operators, the scarcity of human resources for manual
silvicultural operations, and the limitations on the use of management chemicals poses
significant practical limitations that must be accounted for in the way in which
management operations are constrained and mixedwood silviculture is planned. In
particular, the objective of intimate mixtures carries with it a much greater cost, labor and
experience requirement than the use of coarser grain mixtures.
4.4 It is recommended that as an interim 5 year measure, the Licensee’s proposal to
only manage 300 ha of the deciduous stands eligible for understory protection as
mixedwood stands be accepted based on the practical limitations of the length of the
harvesting season. However, by relaxing the standards on well spaced stems, much of the
additional eligible areas may well be capable of being harvested with significant
understory spruce retention but without the additional costs in time and money. The
objective would be to retain some as-yet-to-be-determined proportion of the spruce
understory on this additional area. The objective of this 5 year interim agreement would
be to refine systems of harvest in potential understory retention stands based on a
compromise between not increasing harvesting cost and retaining as much understory as
possible. Part of this 5 year period would be used to improve operator training with a
view to a steady improvement in understory protection without additional time and
financial costs.
4.5 Improved methods of predicting the release growth response of understory spruce
are needed to improve the choice as to which stands will receive the full understory
retention investment, and which will receive a partial understory protection treatment.
4.6 The issue of stumpage and cost allowances for aspen needs to be re-examined to put
spruce and aspen on more equal terms in management.
4.7 There is an urgent need for a better inventory of large-scale landscape pattern and the
range of stand structures. There is also a need for a better ability to predict stand
dynamics. There is an equally urgent need for scenario analysis, decision support tools
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with which to explore the efficacy of alternative policies and practices to achieve
whatever objectives are developed with respect to these patterns and structures.
4.8 Perhaps the single most interesting concept to come out of this analysis is the idea of
a portfolio of stands of different ecological characteristics that could be used, in
conjunction with landscape-level objectives that are yet to be derived, to optimize both
the social values associated with timber harvest and the long term sustainability of a
variety of values provided by the boreal landscape.
Given a portfolio of stands for which cutting plans have been developed, and a set of
objectives, a licensee would be able to select a set of stands that most closely meet its
economic objectives for the year, but which also stays within, say, 50% of the profile of
the desired balance of C, CD, DC and D stand types, and within a target % of the
objectives for the proportion of the mixed stands exhibiting a desired frequency
distribution of degrees of clumping and intimacy of the mixture. At each 5-year Timber
Supply Analysis the Licensee would be required to be within, say, 10% of the target
distributions, and these targets could be adjusted every 10 years to account for any failure
to achieve desired outcomes over the previous period.
Closing Thought
A key element in the definition of the contemporary paradigm of sustainable forest
management – ecosystem management – is to manage a forest landscape within the
socially acceptable (implying the establishment of objectives) portion of the historical
(temporal) and spatial variability that is characteristic of that forest type in the area/region
in question. A second key element is adaptive management – learn by trying different
things, and don’t do the same things everywhere. In a forest that is so subject to
disturbance, ecosystem management and adaptive management would be greatly
facilitated by giving the Licensees landscape and stand-level targets, and the flexibility to
manage a portfolio of stands. Allowing trades to account for unexpected successional
outcomes, or simply natural disturbance and the normal successional processes of
change, and allowing variation in outcomes in any year but requiring conformity to
within 10% of the objectives every 5 years, would seem to be a practical way by which to
get the greatest social values out of these forests while meeting social, cultural and
environmental objectives.
While I recognize that the MoF has the difficult mandate to monitor Licencee compliance
with targets and objectives set by the MoF, forestry must not be designed and driven by
this administrative imperative. It must be driven by respect for the ecology of the values
that are to be sustained, and by the practical limitations imposed by nature and society on
what we can and cannot achieve in a particular forest.
Not all the questions that were raised at the outset of this assignment have been answered.
The reasons for this short coming include lack of knowledge, lack of definitions, lack of
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adequate inventories, lack of experience of the outcome of alternate strategies, and lack
of appropriate ecosystem management models with which to explore issues and questions
that cannot be answered the best way – experience and critical observation of the forest.
The issues raised in this report are significant for the management of boreal
mixedwoods. Many of them simply cannot be answered in the short run. To do so would
be arbitrary and unproductive. I recommend that the MoF commit the resources to
undertake the inventories, studies, and modeling investigations that will lead to a more
logical solution to the questions.
Acknowledgements
I would like to express my appreciation to the staff of MoF Victoria, Prince
George Region and Fort Nelson District, and to Slocan Group, Fort Nelson Woodlands
staff for their helpful assistance in all aspects of the preparation of this report, for the
civility and friendly atmosphere in which all the discussions and field trips were
conducted, and for their efforts to inform me of the complexities of the issues involved. I
would also like to thank the reviewers who pointed out some errors in fact and
interpretation in an earlier draft of the report, and identified some topics that were
omitted from that draft. I have attempted to address all the comments with which I
agreed. Remaining errors of understanding and interpretation remain my responsibility. I
would also like to thank my secretary, Maxine Horner for her tireless efforts to assist me
in my work, and for helping with travel arrangements and for some of the typing.
C:\kimmins\reports\Slocan Forest Products report to MOF.doc
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