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The Healthy Multiple-Use Forest Ecosystem:
An Impossible Dream
Michael R. Wagner1
Abstract...;.. Forest health is a widely used term that is viewed by many
managers and users as a desirable future condition for the nation's forests.
However, the definition of a healthy forest is subjective, a function of
objectives, and highly dependent on whether the forest is viewed from the
utilitarian or ecosystem centered view. The forest health paradox is created
because forest health is both a future desired condition and dependent on
the future "desired condition. The nature of the forest health paradox is
described. Alternatives for the resolution of this paradox may require
deviation from the multiple-use and explicitly multiresource concept of forest
land management. Some approaches to resolve the forest health paradox
are presented.
commodities to harvest such as timber, fiber, water, forage, and
wildlife. The ecosystem centered view is that a variety of basic
ecological processes occur within the forest, such as
decomposition, nutrient cycling, etc. that should be sustained.
The latter view is that commodities can only be harvested to
the extent that they do not negatively impact basic ecological
processes.
This spectrum of forest uses has lead to divergent views on
how forest health is defined. An example of a utilitarian
definition is provided by the USDA Forest Service (1993):
"Forest health is a condition where biotic and abiotic
influences on the forest (that is pests, silvicultural
treatments harvesting practices) do not threaten resource
management objectives now or in the future. "
This view follows closely the long standing notion of a forest
pest as descn"bed by Batbosa and Wagner (1989):
"A ...... species is considered a pest when it interferes
with the intended use of a tree, forest or forest product.
The relationship between intended use and type of injury
determines the significance of inflicted damage and the
appropriate strategy for control".
Clearly the essential element in the utilitarian deflnition of
forest health is non-interference with land management
objectives; essentially a healthy forest is one without pests.
In contrast, the ecosystem centered view of a healthy forest
tends to focus on ecological processes and sustainability rather
than commodities. This view is expressed in all of the following
definitions:
INTRODUCTION
Forest health is a concept that is currently widely used in the
context of a desirable future condition for forests. The notion
of maintaining a "healthy forest" is currently popular and enjoys
near unanimous approval by all forest users. The question arises
as to why forest health has such wide support in an eIWironment
ftIled with controversy about the appropriate management
direction for the public forests of America.
The purpose of this paper is to discuss the concept of forest
health, explain why forest health has risen to popular status as
a land management objective and to discuss the forest health
paradox that creates conflict between land management
philosophies such as multiple use, multireSOUICe, ecosystem
management and forest health.
DEFINITION OF FOREST HEALTH
To understand the concept of a healthy forest we first need
to examine the divergent views that individuals have regarding
what forests provide society. Forests are viewed from a
continuum that ranges from the product oriented "utilitarian
view" to the "ecosystem centered" view. The utilitarian view
is that forests contribute to human welfare by providing
1 Professor, School of Forestry, Northern Arizona University,
Flagstaff, AZ.
185
The notion of forest health is popular because evetyone defines
it in terms of their own personal view of what is desirable from
a forest. The wood processing industty supports healthy forests
because they are productive and produce large quantities of fiber.
Wildlife biologists also want healthy forests because they
produce a diversity of wildlife species. Forest health has
unanimous support because it is defined in terms of meeting
objectives and not in terms of specific commodity outputs. Who
would argue that meeting your objective is bad?
"A healthy forest is one that is resilient to changes and
characterized by tree species and landscape diversity
that provides sustained habitat for fish, wildlifo and
humans" (Joseph et al. 1991).
"In the broadest sense, a healthy forest is a description
of a productive, resilient, and diverse ecosystem; a forest
with a future." (Wilson 1991, cited in USDA Forest
service 1993).
"A forest could be classified as healthy if various
biological and physical influences do not threaten
present or future manage"!ent objectives. A forest in
good health is a fully functional community ofplants and
animals and their physical environment. A healthy forest
is an ecosystem in balance'~ (Monning and Byler 1992).
"Healthy is the capacity of the land for self renewal".
(Leopold 1949).
The ecosystem centered defInitions of forest health attempt
to shift the focus of the desirable condition away from
commodities to focus more ·on ecological issues such as
resilience, diversity, ecological balance, and sustaining
ecological processes such as decomposition, nutrient cycling etc.
The notion of a healthy forest as a forest that meets objectives
remains as a basic part of the definition
An issue raised by these divergent views is how to measure
forest health. A commodity driven view of a healthy forest
allows for relatively easy assessment of the level of output. Land
managers generally know how to measure wood volume, forage
production, wildlife populations and so on However, methods
for measuring resilience, ecological balance, and sustainability
remain largely unexplored. The desired level of either a
commodity or an ecological process still needs to be specified
in order to judge whether we have met our objectives. A
common default position for measuring the level of ecological
processes is to estimate the pre-European settlement conditions.
There are some problems with this approach in that it is not
always possible to estimate pre-settlement conditions nor are
those conditions necessarily the most desirable to achieve
management objectives.
THE FOREST HEALTH PARADOX
The above discussion leads us to the forest health paradox.
A paradox is a seemingly contradictoty statement that is
nonetheless true. The forest health paradox is that a healthy
forest is both a future desired condition and dependent on the
future desired condition (objective) for the forest. Basically all
of the definitions of forest health include the element of meeting
objectives. Because forest health is dependent on objectives, then
managing for forest health is a paradox.
Many forest pest management specialists have, perhaps
unknowingly, encountered the forest health paradox. The typical
scenario is that a land manager asks for assistance in
recommendations to reduce incidence of an insect or disease,
for example, dwarf mistletoe (Arceuthobium spp). The pest
specialist usually responds by asking what is the long tenn
objective for the stand. If the manager suggests their objective
is to reduce populations of dwatf mistletoe the pest specialist
usually responds by saying reducing dwarf mistletoes is only
reasonable in the context of a specific objective. Because dwarf
mistletoes play a variety of important ecological roles as habitat
and food for wildlife the particular objective might call for
increasing populations of dwatf mistletoes. In this scenario the
land manager has to either specify objectives or disregard the
input of the pest specialist.
FOREST HEALTH AND LAND
MANAGEMENT PHILOSOPHY
BASIS FOR POPULARITY OF FOREST
HEALTH
The land management philosophy being applied to a
particular land area greatly influences the likelihood of achieving
the condition of a forest considered to be "healthy". Under
conditions of a singular objective the achievement of forest
health is StraightfOlWard. However, the absolute condition of
"healthy" will depend on the singular objective. In other words
what is considered healthy will vaty dramatically depending on
which singular objective is established. However, under
multiple-use or multiresource (simultaneous multiple use Behan
1990) there is no single measure of health that can possibly
measure the degree to which we have achieved the multiple
objectives dictated by these management philosophies.
Consequently, under current definitions of forest health, a
healthy multiple use forest is an impossible dream. If multiple
I have obseIVed over the past 2 years broad scale support for
the notion of forest health. Many professional forest pest
management specialists in Canada and the US now refer to
themselves as forest health specialists. This level of support for
forest health is rematkable given that there are few other land
management issues about which there is any significant
agreement between user groups. What is the basis for this
support of forest health and why has it taken so long for
managers to realize this? The reason for the broad support of
management for forest health is the divergent views of what
constitutes a healthy forest. If you do not have a clear concept
of an idea you tend to define that idea in terms you understand.
186
volume will address the role of insects and diseases in forest
ecosystems and how we might define what are the appropriate
levels that could be defIned as healthy.
The second solution is to adopt a land management
philosophy in which the land base iS'divided into perhaps 3 or
4 groups with distinct objectives. For example, use groups might
include a high yield economic zone to maximize wood fiber
yield, natural reserves to preserve ecological processes, and
wildlife emphasis areas to maximize total species diversity. Just
such a land allocation strategy was proposed by Seymour and
Hunter (1992) for Maine. I refer to this approach as a balanced
land allocation system (BLAST). BLAST would result in
different objectives for each land use category and a more
realistic measure of forest health (degree to which objectives
have been met or specific level of an ecological process) would
be achieved. For this scenario forest health would remain clearly
a function of the management objective and therefore would
vat)' widely. A major advantage is that it would be considerably
easier to arrive at the future desired condition than is currently
possible. This second solution attempts to address what is
perhaps the fundamental issue - For what purpose should the
land be managed? Many of the new approaches to forest land
management do not address this issue of lack of -consensus on
how forests should be used. Until there is agreement on how
forests should be managed there will be little agreement on what
constitutes a healthy forest.
use management is achieved through the aggregation of single
uses across the landscape then it might be possible to achieve
forest health in the aggregate. In this scenario each stand or
single-use area would likely have a different but equally healthy
condition Multiresource management, managing for all outputs
on the same land base, can never lead to a singular healthy
forest.
The emerging land management philosophy of ecosystem
management emphasizes using an ecological approach to
achieve multiple-use management by blending the needs of
people and environmental values in. such a way as to produce
diverse, healthy, productive, and sustainable ecosystems.
Measuring the degree to which land treatments are consistent
with ecosystem management is even more difficult than for other
land management philosophies. The healthy forest under
ecosystem management can only be defIned when the terms
diverse, productive and sustainable have far more precise
meanings than they do now. The Current tendency to define
management philosophy in increasihgly more subjective terms
like sustainable, productive, and diverse only complicates the
detennination of what constitutes a healthy forest.
SOLVING THE FOREST HEALTH
PARADOX
The previous discussion has raised some of the problems
associated with the current usage of the term forest health and
the forest health paradox. To address these problems I propose
two solutions: modification of the notion of forest health to
delete emphasis on achieving objectives and/or modification of
land management toward a balanced allocation of land to
categories of similar uses.
The forest health paradox is created by defining health in
terms of achievement of objectives. For the concept of forest
health to serve a more useful function it must be defIned more
precisely in terms of absolute levels of commodities or specific
levels of a particular ecological process. An example of a
suitable measure of health from a commodity view might be
that a stand produce an annual increment no less than 80% of
the increment for similar managed stands. A suitable measure
of a healthy forest from the ecosystem management view might
be a forest in which forest floor decomposition rates do not vat)'
more than plus or minus 50% from unmanaged stands or perhaps
where decomposition rates are within the range of
decomposition of managed and unmanaged stands. Defining the
levels of any process that falls within the healthy range would
require considerable research effort in understanding the role of
various agents such as insects and diseases under widely variable
stand conditions. Many individuals have viewed variation in
populations of insects and diseases as indicators of unhealthy
conditions. Determining if a particular population level was
unhealthy would be entirely dependent on the natural variation
which is indeed enormous for many insects. Other papers in this
CONCLUSIONS
In this paper I have discussed the utilitarian and ecosystem
centered views of a healthy forest. DefInitions to date generally
have "achievement of objectives" as an important theme. This
component leads to the forest health paradox which is created
when a healthy forest is both a future desired condition and
dependent on the future desired condition of a forest.
Considerable rethinking of the defInition of a healthy forest
or of land management strategies is needed. In addition, a greater
focus on understanding the role of all components in forest
ecosystems, including the physical and biological components
(ie., microbes, insects, diseases, animals, plants etc.), is needed.
Adopting the goal of managing for healthy forests does not
simplify the task for forest managers.
LITERATURE CITED
Barbosa P. and M.R. Wagner. 1989. Introduction to Forest and
Shade Tree Entomology. Academic Press, San Diego. 639
pp.
Behan, R.W. 1990. Multiresource forest management: a
paradigmatic challenge to professional forestry. Journal of
Forestry. 88(4): 12-18.
187
Seymour, R.S. and M.L. Hunter Jr. 1992. New forestIy in eastern
Spruce-Fir forests: principles and applications to Maine.
Maine Experiment Station Misc. Publication 716. 36 pp.
USDA Forest SeIVice. 1993. Healthy forests for Americas
future: A strategic plan USDA Forest SeIVice MP-1513. 58
pp.
Joseph, P., T. Kieth., L. Kline, 1. Schwanke, A. Kanaskie, and
D. Overhulser. 1991. Restoring forest health in the Blue
Mountains: a 10 year strategic plan. Forest Log 61(2): 3-12.
Leopold, A. 1949. A Sand County Almanac and Sketches Here
and There. Oxford University Press, New Yolk. 226 pp.
Monnig, E. and 1. Byler. 1992. Forest health and ecological
integrity in the Northern Rockies. USDA Forest Service FPM
Report 92-7. 19 pp.
188