The text below provides a
detailed description of the Shifting Mosaic Project. Please select one of the following to
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Introduction
Almost three-quarters of timberland in the United States is under private ownership. These
lands do not have the multiple-use mandate of National Forests. Rather, often their chief
purpose is to provide raw material for forest products. However, the ecological importance
of this huge landbase cannot be dismissed or undervalued. Integration of ecological and
economic goals on private timberlands will be essential to maintaining the nation's
biodiversity. Achieving such integration will require models for land management that do
not threaten the private rights of landowners. Such a model is described below for private
industrial forestlands.
In the northeastern U.S. the 26 million-acre Northern Forest region stretches from
northern New York, across Vermont and New Hampshire, to the northern tip of Maine. This
area is unusual in the eastern U.S. because forest cover dominates the region and the
human population is low, despite its proximity to the New York-Boston population centers.
It also is a region dominated by private land ownership. In Maine, large industrial forest
products companies alone own 10 million of Maine's 15 million acres of Northern Forest.
Clearly any effort to maintain the biological diversity of the Northern Forest must
involve those who own most of the forest- i.e., forest products companies.
The Northern Forest has been under intense public scrutiny especially since the
formation of the Northern Forest Lands Council in 1990. The mission of the Council was to
identify mechanisms and policies that would reinforce traditional patterns of land
ownership and uses of the 26-million-acre forest. Although the Council disbanded in 1995,
it served as a catalyst for even greater public attention on the forest. Numerous examples
demonstrate this attention in Maine. First, the Governor of Maine has formed a Forest
Sustainability Council to develop principles of sustainable forestry for the state.
Second, a consortium of stakeholders formed The Maine Forest Biodiversity Project in 1994
to find common ground between ecological and economic interests. And third, a
referendum appeared on the November 1996 ballot giving the public the option of voting to
ban clearcutting in Maine. All of the efforts reflect an intense interest in the
forest. Both ecological and economic demands on the forest are not likely to subside soon.
Finding common ground is easier said than done. This derives partly from the fact that
different people place different values on natural resources. For example, those in the
forest products industry place may place a high value on the potential of a tree to be
converted to paper or dimensional lumber. Hikers might place a relatively lower value on
this use of a tree, and a higher value on it as a foraging base for birds, as a sink for
CO2, or as simply an aesthetically pleasing structure.
Conflict surrounding natural resources and the environment often is precipitated by a
perceived threat to one's values. While different values are, and always will be, a
feature of human society, there is a way to help reduce this conflict such that mutually
agreeable solutions can be discovered. Values often are threatened by lack of information,
and/or poor communication of information, whereby stakeholders cannot determine the true
degree of threat to their values. This uncertainty naturally leads to conflict. Any single
clearcut might look appalling to the hiker. But if it can be determined that as much or
more wood is growing each year than is being cut, the threat to the hiker's values might
be mitigated. In light of accurate information, it may become apparent that the threat was
only perceived, or, that the threat was in fact real. Either way, the various stakeholders
have a much stronger basis for making policy decisions that protect the values of
everyone.
Conflict also is generated when society fails to set specific goals. So far the
environmental community in the region has been critical of clearcutting, herbicide
spraying, plantations, and an array of other forest practices. However, their goals for
the forest have not been clearly defined. It is difficult for the forest products industry
to develop forestry practices (or avoid certain practices) to meet end points that are not
identified. Similarly, the forest products industry has not been open with the public on
how it intends to shape the forest over the coming century. How much of the Northern
Forest will be in plantations? Will the average age of the forest become younger as
technology finds ways to make uses of an ever-younger forest? Can plants and animals
indigenous to the region be maintained in such an evolving landscape? The environmental
community does not have the information it needs to determine whether the future forest
can accommodate its interests. At present, such information does not exist.
The Shifting Mosaic project directly addresses both sources of conflict. First, the
model sets specific economic and ecological goals for private industrial timberlands.
Second, the project requisitions a multi-disciplinary scientific team to meet these goals.
And third, the project establishes new and efficient mechanisms to get scientific
information to the public. The Shifting Mosaic is thus a biological, economic, and
sociological initiative.
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Model Concepts and Goals
The Shifting Mosaic Model sets two specific goals for private industrial forests:
(1) Economic goal - forestry operations in the model area can proceed at a level that
meets the economic expectations of the landowner, so long as a sustained flow of wood can
be maintained for the long-term (century scale), and
(2) Ecological goal - self-sustaining populations of all plant and animal species
indigenous to the area must be maintained indefinitely.
At the present time we do not know whether both goals can be met simultaneously on
private industrial forestlands. Therefore the model makes no guarantees for success. We
have never tried to integrate these goals in the industrial forest in the Northeast. While
the ecological track record of industrial forestry has been good in New England over the
last two centuries, there can be no guarantees that the future holds the same prospects.
Recent advances in forestry and forest products technology have changed the stakes. These
changes make it critically important that ecologists and foresters begin working together
now to understand and design the forests we will know decades in the future.
Achieving either goal alone will be considered model failure. However, the model may
fail under some circumstances and succeed in others. The model can be applied to any
industrial forest landbase. Different companies produce different products. Those that own
a pulp or paper mill must go about forestry in a different way than a company that owns
only a sawmill, or a company that only owns timberland and no mill. The model is goal
oriented, not method oriented. The landowner is free to achieve the goals using whatever
silvicultural practices may be available. The model assumes that there will be many
"solutions" to meeting the goals of the model. Indeed, there is no a priori
reason to assume that either a clearcutting-dominated or selection-cutting dominated
forest management strategy could not meet the goals of the model. Success may be more
critically related to harvest rate than harvest method.
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The Design Team
Achieving the economic and ecological goals through forest management and landscape design
is the responsibility of a technical Design Team. This team will be composed of ecologists
with different expertise (mammalogy, hydrology, botany, ornithology, etc.), forest
economists, and foresters from within and outside the landowner companies. With the
exception of landowner foresters, the team will be assembled from organizations that have
the necessary scientific capability in the region (universities, Forest Service, research
stations, etc.). Landowner foresters are considered vital to the team because they know
the specific model areas and will be best able to apply the plan on the ground.
While the landowner is free to place constraints on the Design Team, such as which
silvicultural or harvesting methods must be used, the Design Team will report its work
openly to the public (see below). While high economic demands are allowed by the model,
such demands will make the ecological goal more difficult to achieve. Presumably,
integrating the work of the Design Team into forest management will enhance the
probability of success. However, if the Team ultimately cannot meet the goals, given the
constraints, those results and conclusions will be shared with the public just as would
data indicating success. Such open communication of results is the hallmark of the
project.
The work of the Design Team does not end with creation of the landscape plan. Once the
plan is developed, the Team will be responsible for developing and implementing a
monitoring program to evaluate the success or failure of the plan. The team also will be
expected to develop an ongoing research program that identifies and fills information
gaps. With better information on the ecology of plants and animals in the model area,
silviculture, and the relationships between forestry and forest ecology, the plan can be
modified over time to improve its potential to meet the dual goals.
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The Biological
Basis
The name "Shifting Mosaic" represents a biological strategy for achieving Goal
2, which is to "shift" plant and animal habitats through space and time, by
design, and in coordination with short- and long-term harvesting plans. Maine's forest is
naturally a mosaic of habitats, including conifer forest, deciduous forest, and various
age classes of each. Plant and animal species each are adapted to certain habitat types.
Industrial forestry has the effect of accelerating the rate at which this natural mosaic
shifts within the landscape. The Shifting Mosaic Model proposes to shift habitats across
the landscape, over the decades scale, in a configuration that allows plant and animal
populations to "track" suitable habitat. This is quite different from the
landscape approach to harvesting today, which is basically haphazard with respect to
species' population dynamics.
This Shifting Mosaic Model will attempt to maintain, at all times in the future,
sufficient habitat of all types necessary to sustain all plant and animals species in the
landscape. The abundance of any single habitat may ebb and flow over the decades scale
with different levels of harvesting. Populations of plants and animals associated with
each habitat will fluctuate in tandem. However, by landscape and forestry planning at the
decades to century scale, we should be able to anticipate how much, and where, patches of
each habitat will be (within limitations imposed by nature and stochasticity), and what
the implications will be for plant and animal populations.
Shifting plants and animal populations across the landscape must be done by design.
Different species have different dispersal capabilities and different area requirements.
Many herbaceous plants cannot disperse very far or very fast. By contrast, moose, bear,
and most birds are much more vagile, and can track a more rapidly shifting landscape. To
this end, the Shifting Mosaic Model incorporates these different dispersal capabilities in
the design of the landscape (Fig. 1). Small-scale shifting mosaics will be designed to
maintain slow dispersers in the landscape, and will be nested within larger-scaled mosaics
that will support fast dispersers, and those that benefit from larger tracts of habitat.
The Shifting Mosaic Model is based on (1) species' habitat requirements, (2) species' area
requirements, and (3) species' dispersal capabilities.
Figure 1. A conceptual diagram of
the Shifting Mosaic Model. Harvesting creates a variety of successional stages of forest
(represented by shades) in the landscape, and these stages "move around" over
time as the forest regrows. Ideally, each successional stage would be colonized by th
efull complement of plant and animal species that use that particular stage of forest
growth. However, different plant and animal species have different dispersal and
colonization abilities. Many herbaceous plants do not move very far or very fast, and may
not be able to "keep up" with a large-scale shifting mosaic of habitat types. By
contrast, most mammals and birds are more vagile, and populations of such species can more
easily "track" habitat as it move across the landscape over time. To keep both
"slow" dispersers and "fast" dispersers in the landscape, different
sized shifting mosaics will be applied to the landscape. The small-scale mosaics would be
designed to best accommodate slow-dispersing species, whereas the larger-scale mosaics
would accommodate faster dispersers, as well as provide some large tracts of unfragmented
habitat. Each mosaic, whether large, medium, or small, is fixed in space and does not
migrate through the landscape as do the successional stages of forest within each mosaic.
The Shifting Mosaic is a modification of Harris (1984).
Although many ecological processes are critical to maintaining biodiversity, the
Shifting Mosaic Model takes a species and landscape approach to biodiversity. This
strategy was adopted because we have far less understanding of ecological processes than
we do of species. To set as a goal "maintaining allecological processes" would
have been even more challenging than maintaining all species. However, forest management
under the Shifting Mosaic will constantly strive to integrate processes that we know make
important contributions to ecosystem functioning (e.g., dead and dying trees, coarse woody
debris, the hyporheic zone along streamsides). With respect to many yet undescribed
species, such as those that might live in the soil, we may be much more likely to succeed
at meeting the ecological goal of the model by maintaining the process first. The model
does not exclude such an approach.
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Monitoring
Both ecological and economic monitoring programs will be necessary to evaluate the
effectiveness of the landscape plan at meeting the goals of the model. Economic monitoring
includes measuring the flow of wood out of the model area, and growth of wood in the model
area.
Monitoring "all plant and animal species" is more problematic for several
reasons. First, species exist that science does not yet know about; therefore, how can
they be monitored? Second, even if we did know all species that occur in the model area,
it would be impossible, and prohibitively expensive, to monitor them all.
While the ecological goal of the model, to "maintain self-sustaining populations
of all plant and animal species," may seem unrealistic, an alternative goal of
"maintaining some, but not all, plant and animals species" would not challenge
our technical skills. Nor would it be an especially ambitious goal for industrial
timberlands. With the latter goal, whatever species we were able to maintain would be
maintained, and whatever could not be maintained, we would not have to worry about. Under
the Shifting Mosaic, our technical skills will be applied in an effort to do a complete
job.
While the Design Team cannot be responsible for maintaining species that are as yet
unknown, if new species become known to science, they will then fall under the ecological
goal of the model.
Because all plants and animals cannot be monitored, the Design Team will identify,
based on life-history information, those species that should be most vulnerable to
industrial forestry. In Maine's industrial forest, these are most likely to be species
that need or prefer older forest, or structure associated with older forest, because such
forest is decreasing in abundance. Less monitoring effort should be required for species
that use early-successional forest, a common habitat in the industrial forest. Species
that have very narrow habitat requirements, and species that require or prefer habitat
that is, or expected to become, rare in the model area, will receive the most thorough
monitoring.
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Spatial Scale
The Shifting Mosaic is a landscape-scale model. The ecological goal requires that species
be maintained within the landscape, though their location(s) and abundance(s) can change
over time. As noted above, different species operate at different spatial scales, and one
scale cannot fit all.
In northern Maine the land is divided into "political" units called
townships. Most of these townships are uninhabited, but the political boundaries are
convenient for organizing the landbase nevertheless. Many of these townships are 10 x 10
km (6 x 6 mi), or roughly 10,000 ha (25,000 acres).
The Shifting Mosaic Model will attempt to maintain self-sustaining populations of all
plant and animal species within a township. This scale was chosen for two reasons: (1)
because most organisms indigenous to the region can maintain self-sustaining populations
in an area of this size, and (2) loss of species at larger scales may make it difficult to
recover them in any given forest stand, as it becomes suitable habitat. That is, if the
species cannot colonize an otherwise suitable habitat patch because the nearest
populations are one or more townships away, its populations may become unnecessarily
reduced. As habitat comes on-line, it should be "accessible" to species that use
that habitat. The landscape can be designed to enhance the probability of colonization.
Two major forest products companies in Maine have allocated lands to testing the
Shifting Mosaic Model: (1) 42,000 acres of J.D. Irving, Ltd.
timberland east of Baxter State Park, and
(2) 52,000 acres of Plum Creek Timber Company land in the townships of Kibby and Skinner, near Maine's western
boundary. While these areas are somewhat larger than a single township, the model can be
applied at any scale smaller than the full area.
Ultimately, setting the spatial scale at which we maintain plants and animals will be
up to society. Clearly even nature cannot maintain all species on every acre of forest.
Can humans maintain them in every township, across their natural range? We do not know the
answer to this question, but this may be a practical and reasonable scale for application
of our technical skills in forestry and ecology in Maine, bearing in mind that other
societal pressures may direct us toward a different scale in the future.
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Ecological
and Economic Integration
Although there is an economic and ecological goal of the Shifting Mosaic, integrating the
two will require placing economic and ecological metrics in the same equation. The model
avoids the need to assign a monetary value to, say, pink lady's slipper. The goal of
maintaining the species in the landscape has already been set. However, the model can
calculate the economic cost of modifying forest practices so that pink lady's slipper can
be maintained in the model area. Some species may cost nothing to maintain, whereas others
may cost a little, and others quite a lot. Ecologists may determine that, with
clearcutting, insufficient coarse woody debris is generated to maintain populations of
some salamanders. We can develop forest practices to get sufficient volumes of woody
debris in the forest (by topping or girdling live trees, delimbing at the stump, etc.),
and calculate the cost of adopting these practices. Presumably, such costs eventually will
be reflected in the price of whatever forest product is being produced.
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The Public Link
Though industrial forests are privately owned, they provide many benefits of interest to
the public, including a source of livelihood for mill workers and wood cutters, investment
income to stockholders, habitat for wildlife enjoyed by humans, and many sorts of
recreational opportunities. Though its goals are well-defined, the Shifting Mosaic Model
cannot be carried out in isolation of the diversity of stakeholders.
For this reason a Stakeholder Council will be formed to serve as a link between the
Design Team and the public (Fig. 2). This sociological component is crucial to the
project. The Stakeholder Council will be represented by a cross-section of interests. It
will not be a group that is expected to come to consensus about forest practices or to
generate a shared vision for the forest. It will be a group whose function is to help make
technical information generated by the project available to society.
Figure 2. Project structure of
Shifting Mosaic Model. The Design Team is be responsible for constructing a landscape that
meets the goals of the model. The Stakeholder Council will serve as a communications
conduit between the Design Team and the public to ensure information is transferred and
that the information is relevant. The forest products company will have the authority to
modify any aspect of the landscape plan, but such actions and reasoning will be reported
openly to the Stakeholder Council.
The stakeholder council will serve as a two-way communications conduit. The technical
Design Team needs to hear from the public what its questions and information needs are.
Within the context of meeting the goals of the Shifting Mosaic, the Design Team hopes to
address specific technical questions expressed by the public through the Stakeholder
Council. In essence, we hope to create a new and efficient way for scientists to interact
with the public on an important environmental and economic issue. The assumption is that
if the Design Team can respond to some of these information needs, the constituencies will
be in a better position to generate sound forest policy.
The Council will be expected to work towards making this link with the public as
efficient and effective as possible. Specifically, the function of the Council will be:
- to maintain a current, on-going understanding of the Shifting Mosaic Project and its
results, as provided by the Design Team
- to communicate to its constituencies about the project, its objectives, and its results
- to communicate to the Design Team information needs identified by constituencies
- to provide feedback to the Design Team on how well the project is answering the
constituents' questions
The Council will meet two to three times each year jointly with the Design Team. The
Council then will be responsible for completing the information transfer to its
constituencies through mechanisms they deem appropriate. Council members will be free to
communicate the work of the Design Team as they interpret it. Council members will
communicate back to the Design Team their constituencies' concerns and information needs
(Fig. 2) with respect to economic and ecological issues.
The Stakeholder Council also will be charged with helping create new methods of
communicating technical information to the public, and new methods for their
constituencies to incorporate information into their decision-making. The Shifting Mosaic
Project will not direct policy, it simply will serve as a mechanism for getting unbiased
scientific information about ecology and forestry to society. Society is free to use the
information as it sees fit. However, the information will be provided equally to all
facets of society. Different constituencies may then view the information differently with
respect to their own values. The Design Team will not present scientific information as
being good or bad for one issue or another. The effects of certain forestry practices,
whether they benefit economic or ecological goals, will be equally reported. Society can
then interpret whether the effects are "good" or "bad."
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Basic
Tenets of the Shifting Mosaic
There are several principles of the Shifting Mosaic Project that have made it successful
to date. These features should be transferable to other projects dealing with other
societal issues besides forests and forestry. However, it is not suggested that these are
the only features required for any project that attempts to integrate economic and
ecological goals. Rather, they were features necessary, in this case, to make the Shifting
Mosaic Model an active on-the-ground effort.
- Specific goals were established first - The Shifting Mosaic sets carefully formulated,
focused goals. The model was not designed to address all of society's diverse demands for
the forest.
- The project is goal directed, not method directed. This is an important point when
dealing with a diverse forest products industry that produces many different products.
Products often determine what silvicultural strategies a company will employ. By allowing
the companies to develop their own solutions to meeting the specific goals of the model
(through the Design Team), they are not threatened and are free to be creative and
proactive in problem solving.
- The ecological goal is grounded in biology. Species' life-history information is the
basis for designing the ecological landscape.
- The model does not require off-limits biological reserves. The model is specifically
designed for private industrial forestlands. The model does not require any lands to be
set aside or taken out of timber production. It does require, however, that
self-sustaining populations of all plants and animals be maintained. If this goal cannot
be reached without off-limits reserves, that conclusion will be reported to society. Even
so, society will be better informed and better able to formulate appropriate policy to
meets its goals.
- Monitoring. Ongoing monitoring of both economic and ecological parameters will take
place. Without a monitoring program, success or failure of our ability to meet these goals
is left to speculation.
- Independent evaluation. The success or failure of the model will be evaluated by an
independent Design Team of scientists, not the companies or consultants hired by the
companies.
- Open reporting to society. The Design Team and the Stakeholder Council are responsible
for maintaining open flow of information to the public. Failures will be communicated just
the same as successes.
- Adaptive to new information. Given the restricted knowledge base about forestry,
ecology, and the species and processes that operate in the forest, the model must remain
flexible. New research will provide information that did not previously exist, and that
information must be folded into the landscape plans on an ongoing basis. No plan can be
developed for a half-century scale that will be immutable, given the acquisition of new
information and changes in societal demands.
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Conclusion
Society is placing heavy demands on our natural resources, especially our forests. Society
wants affordable forest products and a healthy economy. Society also wants forests to
provide an array of other benefits, including maintaining healthy ecosystems that support
native flora and fauna. Currently we do not have the technical information to evaluate
whether society can have all it wants from the forest, nor have we quantified the
ecological and economic tradeoffs of achieving society's goals. Yet for the public to make
sound decisions about forest policy in the region, the public ultimately will want its
ecological goals presented in an economic context (e.g., state or federal taxes, the price
of paper or lumber). There is little precedent for (1) setting clear and specific
ecological goals, (2) calculating and evaluating ecological and economic tradeoffs, and
(3) then developing informed environmental and economic policy. However, with over 10
million acres of private industrial timberland in Maine, these analyses must be done and
made available to the public.
The Shifting Mosaic Model represents an effort to fairly and effectively provide this
information to society. The project is designed to be a service to society, and is founded
on the premise that well-informed stakeholders will be responsible architects of public
policy that meets the varied needs of society.
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