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EXECUTIVE SUMMARY In his 1938 dust-bowI-era treatise, Richard L. Neuberger described the Pacific Northwest as "the promised land," and certainly the region has appeared to waves of immigrants as a land of greet bounty and promise. The pioneers who followed the Oregon Trail were attracted by the wealth of natural resources-forests, fisheries, rivers, fertile soils-and the opportunity for a new future. Inter immigrants were attracted for much the same reasons, but development of the region's natural resources has led to problems. Among them has been the depletion of old-growth forests, which had supported the development of the wood products industry. With a growing recognition of the importance of old-growth forests for sustaining biodiversity and species dependent on old growth, conflicts with loggingincreased during the 1980 and 1990s. Intervention by President Clinton in 1993 led to adoption of the Northwest Forest Plan. This brought about a sharp reduction in federal timber harvests, the establishment of substantial areas of old-growth reserves, and adoption of environmentally sensitive forest practices on federal forests. Congress asked the National Academy of Sciences to provide basic information to help guide future forest management in the region, and the National Research Council convened the Committee on Environ- mental Issues in Pacific Northwest Forest Management in 1993. The committee was charged to Review the information concerning the current state of knowledge of forest resources. 7

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2 Pacific Northwest Forests . Review definitions of old growth, including biological, economic, social, and physical amenities that old-growth forest provides; provide analyses of age at which a forest becomes old growth; and evaluate amenities characteristic of old-growth forests that can be preserved under different harvesting regimes. Review forest management practices and the effects on resources of the forests and the economic consequences of those practices. Review the use of forest products from the Pacific Northwest and the degrees to which forest products from other parts of the United States can be substituted for them. Clear goals are essential to any effort to rationalize forest manage- ment in the Pacific Northwest. The committee identified four goals that it believes are at the heart of the issues in forest management in this region (see Chapter S): Sustain viable populations of indigenous species Maintain properly functioning ecological processes Meet human needs for forest commodities Satisfy cultural and aesthetic values Those goals provided the general framework for the committee's study and helped to clarify the kinds of issues that are involved in Pacific Northwest forest management. Conflicts arise among them as they are applied in specific circumstances because they cannot ad be maximized or optimized simultaneously. Much of the disagreement regarding policies and protocols in forest management is associated with the relative priorities that should be assigned to each of those goals. THE REGION Significant intraregional variation exists among Pacific Northwest forests. West of the crest of the Cascade Mountains (the "Westside") where rainfall is high, forests are among the most massive in the world. Dominant trees include Douglas-fir, several species of true fir, western red cedar, Sitka spruce, and western hemlock. In the moist conditions, fires are infrequent and fire-return intervals relatively long and highly

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Executive Summary 3 variable. Drier conditions prevail east of the Cascades in Washington and Oregon (the "Eastside") with grasslands and shrublands grading into ponderosa pine forests at lower elevations and lodgepole pine dominating higher elevation sites. Historically, fires in this subregion were more frequent, and fire exclusion in recent decades has encouraged ingrowth of shrubs and shade tolerant trees. The Northern Rocky Mountain subregion of northeastern Washington, northern Idaho, and western Montana is complex with regard to climate, substrate, and biota. Forests in this subregion are influenced by catastrophic, stand- destroying wildfires. Douglas-fir and true firs dominate some sites, but iodgepole and ponderosa pines, as well as larch, are common. Quaking aspen is widely distributed across this region in burned and logged areas. Basic patterns of land ownership were set in the mid-nineteenth century. Federal public-domain lands were sold or granted to encour- age settlement and development; others were established as national parks and forests. Substantial lands went cLirectly into private owner- ship under various homestead and other laws. Grants to railroads in the region were made in broad swatches, creating a weB-known "checker- board" ownership pattern that has complicated management. About half the land in the Pacific Northwest is in public ownership; most of that land is managed by the U.S. Forest Service (USES) and Me Bureau of Land Management (BEM). The states have forest and other natural resource lands, most of which were obtained from the federal government when statehood was granted. American Indian tribes and the Bureau of Indian Affairs manage large tracts of land on reservations scattered throughout the region. Private owners have hoicLings that range from small woodiots to millions of acres of industrial forests owned by large corporations. THE DYNAMICS OF PAC/F/C NORTHWEST LANDSCAPES Disturbances such as fire, wind, and insect and pathogen outbreaks occur naturally in all Pacific Northwest forest types, although the frequency, intensity, and spatial extent of such disturbances vary considerably. Such variations generate different patterns of forest

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4 Pacific Northwest Forests succession and thereby contribute to the diversity of Pacific Northwest landscapes. Among the various kinds of natural disturbance, fire has been most important. On average, fire frequency decreases with ~ ._ _ ~ A. ~ v ~ incr~.~in~ moisture availability, and fire intensity is generally inversely related to frequency. In forests typified by short fire-return intervals, fires are usually confined to the fine fuels on the forest floors. In addition to permitting natural succession of other species, longer fire- free intervals permit invasion of transV~ressive trees and accumulation of fuels that can carry fires into the forest canopy. Before settlement of the Pacific Northwest, fire-return intervals and fire intensities varied considerably among the forest types of the West- side. Moderate-severity fires at 25-100 year intervals were the norm for Douglas-fir (without hemlock), mixed evergreen, red fir, and lodgepole pine forests. Longer fire-free intervals (100 to 400 years) and more intense fires were typical of other Westside forest types. The drier ponderosa pine forests of the Eastside typically experienced frequent (5- 10 year) fires, which kept understories open and minimized fuel accumulations. To the extent possible and within the range of natural variability, disturbances such as fire should be maintained. Fire regimes have been altered in complex ways by human activities. Development of urban centers and transportation networks, increased recreational use of forests, and timber activities have increased the frequency of fire starts. Suppression of light surface fires has resulted in increased accumulation of fuels in many Pacific Northwest forests. That has been especially important in the ponderosa pine forests of the Eastside and in Idaho and Montana. The extent andlandscape-leve!continuity of early-succession- al forests has increased across the region. Taken together, those factors have resulted in conditions that are favorable for extensive, high- intensity fires in these parts of the region. Although prescribed fire is important and necessary to reduce fuel accumulations and restore landscapes to a less flammable condition, it is not possible to deal with the spatial extent of the problem with that too! alone. Thus, logging and other human management interventions have been proposed as surrogates for fire in this regard. Just as the effects on ecological processes and biological diversity of natural disturbances such as fire are highly variable, so are the effects of human activities, such as logging and forest thinning. Without attention to

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Executive Summary 5 specific goals such as fuel Toads, structural features or "legacies" important to post-disturbance regeneration, biodiversity, and patterns of post-harvest recovery, silvicultural treatments might not simulate important fire effects nor have the desired effect on landscape flammability. More research is needed into the importance of specific factors. Recommendation: The important roles of natural distur- bances and legacies in sustaining ecological processes must be recognized in forest-management practices for both federal and nonfederal forests in the Pacific Northwest. THE B/O! OG/CAL D/VERS/TY OF PAC/F/C NORTHWEST FORESTS Much of the biological diversity of Pacific Northwest is associated with late-successional and oicl-growth forests. If stable and sustainable forests and associated ecosystem amenities are clesirecl in the Pacific Northwest, those forests should be managed to preserve genetic and species diversity. The remaining late-successional and old-growth forests could form the cores of regional forests managed for truly and indefinitely sustainable production of timber, fish, clean water, recreation, and numerous other amenities of forested ecosystems. The multiple threats to biodiversity caused by past forestry practices and the effects of lost biodiversity on ecosystem processes and sustainability demand a new approach to forest management that acknowledges the connection between biodiversity and the sustained provision of commodities and amenities from forests. Further cutting of Me remaining late successional and old-growth forests of the Pacific Northwest is ex- pected to cause rap- idly accelerating threats to the bio- logical diversity of the region. The number of fish, The mu/tip/e threats to biodiversity causes/ by past forestry practices and the effects of lost biodiversity on ecosystem processes and sustainabi/ity c/emanc/ a new approach to forest management.... l

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6 Pacific Northwest Forests bird, mammal, amphibian, plant, and invertebrate species already threatened or endangerecE with extinction because of past land-use practices likely represent about one-fourth of the number of species that would be threatened if just half of the remaining late-successional and old growth forests on public lands were to be harvested. If preservation of biodiversity is to be effective, it is imperative that the region be managed to maintain within the landscape at least the current propor- tion of late-successional and old-growth forests. These should be supplemented with adjacent or nearby second-growth forests, including naturally regenerated stands, that are allowed to attain old-growth characteristics by having rotation times of at least 150 years. In so doing, it is critical that the ecosystem types that have received greater propor- tional cutting, especially the low-elevation forests of the Westside, be provided the highest level of protection and restoration. Research is needed to develop restoration prescriptions. Forest vitality shouIcE be restored and maintained. Development of a clear strategy is crucial if biodiversity is to be protected; management by intuition is insufficient. Success of such a strategy will depend on preserves, and success of preserves will depend on management of the surrounding landscape. Recommendation: Forest management in the Pacific Northwest shout include the conservation and protection of most or all of the remaining late-successional and oIc3- growth forests. Protected areas that include late- successional ant! oIc[-growth forests shout have an impor- tant role in an overall strategy for forest management in the region. Not ail ecosystem types are represented on public lancis in the Pacific Northwest-examples of gaps in coverage include lowland floodplain forests, oak woodlands, and coastal tidal marshes. Checkerboard ownership of public and private lands hinders effective management of forest ecosystem patterns and processes. Opportunities such as land exchanges might offer ways to obtain critical habitats and create public and private management boundaries that are consistent with the behavior of ecosystem processes.

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Executive Summary Recommendation: Goals for protected late-successional and old-growth reserves should include representation of the range of forested ecosystems in the region. This should include rationalization of reserve boundaries, and land exchanges between public and private landowners should be pursued. OLD GROWTH FORESTS Old-growth forests are defined by five characteristics: 1. A minimum density (16-50/ha) of large (52-92 cm diameter at breast height (dbh)) trees (the exact number and size thresholds to qualify as old growth vary among forest types) 2. High standard deviation in tree diameters 3. Tree decadence, i.e., broken tree tops, excavated bole cavities, root- colIar cavities, and bark resinosis 4. Presence of large dead wood 5. Complex, multilayered tree canopies Old-growth forests are ecologically unique with respect to their complexity and biodiversity, accumulations of logs and woody debris, and resistance to disturbances, such as fire and insect and fungal pest outbreaks. But there is no precise threshold age et which forests become old-growth. Forests can be classified as old growth as early as 150 years or as late as 250 years. Forests acquire old-growth characteristics gradually, showing some earlier than others. The rates of acquisition of old-growth characteristics vary with nutrient and moisture availabil- ity and residual forest components from the predisturbance stand. It is important to acknowledge that old growth is a continuum of processes, rather than a simple definition. Some researchers have developed indexing approaches to accommodate that continuum. In the western Cascades, oid-growth forests have been reduced from 40-70% of the landscape in presettlement times to 13-~% today. Estimates of presettlement extent of old-growth forests vary depending on assumptions about the frequency of crown-killing fires. Old-growth

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8 Pacific Northwest Forests ponderosa pine forests might have composed as much as 90% of the lower and middle elevations of the eastern Cascades. Approximately 20% of public and private Eastside lands remain in old-growth today. On Westside and Eastside landscapes, old-growth forest stands are, on average, becoming smaller and increasingly fragmented. Late-successional forests, which are not the same as oIc3-growth forests, are characterized by the invasion of shade-tolerant species. This usually occurs only in the absence of significant disturbances, which maintain the dominance of less shade-tolerant species, such as Douglas- fir and ponderosa pine. Thus, because of intermittent fires that tend to maintain these species even to old age, true late-successional forests are relatively rare in the Pacific Northwest. FOREST PRODUCTS SUBST/TUTION Increasecl timber harvests in the U. S. South and increased softwood lumber imports from Canada, both in response to ordinary market forces, together have offset the reduced timber harvests on federal forests in the West. Total consumption of softwood wood products in the United States does not appear to have been substantially reduced. The reduction in federal timber harvests has been accompanied by some increase in the price of softwood lumber to consumers and in more substantial increases in prices paid for timber that is harvested from federal and nonfederal forests. The expected effects of adopting the Northwest Forest Plan on some biological resources in the Pacific Northwest were examined at length and were largely addressed in the plan (FEMAT ~ 993~. The potential effects on products other than timber, such as recreation and special forest products, were not thoroughly evaluated in that report, partly because of the lack of good information. But it is clear that the reduc- tions in federal timber harvests in the Pacific Northwest favor some kinds of game and nongame species of wildlife over others, affect hunting conditions, improve habitat for fisheries, and maintain opportunities for recreation in the region. Sustaining the increased level of timber harvests in the South, which come mainly from private forests, will require more intensive manage- ment practices because of the reduction in federal timber harvests in the

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Executive Summary 9 West. The possible effects of such practices on biological resources, such as wetlands and the red cockaded woodpecker, apparently have not been carefully evaluated. Similarly, possible effects on employment and communities in the South have not been carefully evaluated. Pressures on forests for all uses in the Pacific Northwest and elsewhere In the United States will probably continue to rise in response to basic cLemands for materials, space, and environmental amenities. The increasing production of wood products on private forests is leading to lower ages of trees at harvest and more intensive silvicultural operations such as thinning, use of improved genetic stock for single- species planting, fertilization, and increased use of pesticides. Tracking these changes and being prepared to take action when the effects are judged to be serious are challenges for public policy. Recommendation: Regional assessments of the impacts of increasingly intensive forest-management practices, espe- cially on private forests, should be conducted to evaluate the impacts of shifting regional patterns of timber harvesting. In particular, an assessment is needed of the effects on key species and ecosystems in the U.S. South of increased timber harvests and management intensity that has resulted! from reducer! timber harvests on federal forests in the West. FOREST MANAGEMENT AND HUMAN COMMUN/T/ES Claims that adopting the Northwest Forest Plan would devastate the economy of the Pacific Northwest have proven to be greatly overstated. The Impacts on the reg~on's overall employment and income have been modest. More timber-related jobs have been lost in recent decades to increases in efficiency and productivity than to reductions in timber harvests. At We same time, some communities heavily dependent on federal timber harvests have had a difficult time, although even these impacts have been eased by the region's buoyant economy. As with other kinds of rural communities dependent on extractive resources, rural communities in the region are experiencing the overall

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10 Pacific Northwest Forests social consequences of changing resource use. The social forces that affect rural areas are powerful, but poorly understood. The conceptual, analytical, anct information bases for relating changes in forest manage- ment to economic and social consequences need to be improved. Experience with the multiyear process leading to adoption of the Northwest Forest Plan also suggests the need to address ways to reduce conflicts over forest management issues. Alternative mechanisms for dispute resolution need to be examined and their appropriateness for situations such as that in the Pacific Northwest evaluated. Recommendation: Experience with FEMAT, the Northwest Forest Plan, and other processes used to help resolve disputes over Pacific Northwest forestry practices should be used to explore alternative mechanisms for dispute resolu- tion. FOREST MANAGEMENT FOR THE FUTURE Forest management is far more than logging, silviculture, and fiber extraction. it must account for management of a variety of landscapes to achieve maintenance of key processes. The committee viewed forest management within the context of four elements: allocation of {and to particular uses, rationing or scheduling of use, harvest of forest products, and investment in productive resources. Pacific Northwest forest managers face significant challenges with regard to each of those elements: Allocation. Most allocation decisions are made within particular ownerships and, thus, at scales smaller than ecosystems and landscapes. Rationing uses. No single rotation age or age between successive cuts fits all forest management goals or circumstances. However, the age at which forests become "financially mature" (i.e., the age at which the cost of holding trees exceeds the increase in value expected over that time) from the standpoint of fiber production is often considerably shorter than optimal rotation ages for other management objectives. Harvesting. Logging and postharvest planting methods have changed

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Executive Summary 7 7 through time with changes in our knowledge and differences in owners' objectives. In general, harvest practices are changing in ways that maintain or increase site productivity that reduce impacts on forest values, such as biocliversity and aesthetics, but further improvements in this area are needed. Investment. Positive and negative incentives are influencing forest- management investments in the Pacific Northwest. Higher timber prices provide financial incentives for investments in timber production, such as postharvest site treatment, fertilizer application, and precommercial and commercial thinning. -- ~ However, uncertainty regarding interpretation of the Endangered Species Act may be creating incentives for premature timber harvest and reduced management levels on some private lands. This has been offset to some extent by some private forest owners who adopt habitat conservation plans, which remove some of the incentives for premature logging. Ecosystem management or sustainable forest management provides a framework for forest management in the context of competing goals and objectives and across scales of time and space. Key elements of this framework are Operational goals. Goals should be formulated in terms of ecosystem processes, as well as economic and social outcomes, so as to provide measurable benchmarks for success of management policies and practices. Context and scale. Managers must be cognizant of connectivity within forest landscapes and recognize that activities at one location influence processes and outcomes at nearby and sometimes distant locations. The spatial and temporal context for management decisions should match the scales of ecosystem processes critical to sustainability. Forest ecosystems are constantly changing and such change is often critical to their long-term functioning. This reality is especially important in the drier forest types of the Eastside where fire exclusion has resulted in accumulations of fuel, an abundance of densely stocked young stands, and, consequently, increased risk of wildfire and outbreaks of insects and pathogens. Complexity and! diversity. Management practices for any one species or element must recognize that suitable habitat encompasses aTi of the

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72 Pacific Northwest Forests other species and ecosystem processes on which that species depends. The area of habitat expected to sustain viable populations of species through time must be sufficiently large to buffer inevitable fluctuations in population size. A landscape or regional approach to distribution of reserves and connections between them is critical. Uncertainly and surprise. Uncertainty results from complex, often unpredictable interactions among ecosystem elements, limited ecologi- cal understanding and poorly developed principles upon which models of ecosystem behavior can be constructed, and poor data quality, sampling bias and analytical errors. Although risks can be reduced, managers cannot eliminate surprises. Adaptive management is critical to dealing with this reality. Humans as ecosystem components. The effects of human activities on ecosystems-including effects on forest structures and on ecosystem processespresent important management challenges. Although forest managers have amended manage- ment practices to account for changes in markets, social values, uncertainty and risk, and changes in our understanding of the effects of management practices, management must become more flexible in the face of even more rapid changes in human effects on and demands from lanctscapes and significant changes in our understanding of such factors as context, spatial and temporal scale, and landscape change. Appropriate levels of management must incorporate a well-de- signed and properly managed system of protected reserves. Appropriate /eve/e of management must incorporate a we//-designed and properly managed system of protected reserves. Recommendation: A formalized approach for adaptive management should be developed and applied in evaluat- ing the effects of forest management practices on key ecosystem properties and to guide changes in these practices that reflect forest conditions at all spatial scales.

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Executive Summary RESEARCH RECOMMENDAT/ONS 73 As noted throughout this report, better knowledge is needed for guiding forest management and resolving issues in the Pacific Northwest. An accelerated program of research is needed to fill these gaps; similar gaps exist for other regions of the country as well. Various institutions and sources of funding play important roles in forest-related research in this region and in the country as a whole. The federal role in funding both in-house and extramural research is obviously very important, but the states, forest industry, and nonprofit organizations also provide research support. The committee believes all of these institutions can take part in supporting and conducting the needed research. In particular, the federal government should substan- tially strengthen its support for a competitive research grants program that would recognize the broad array of scientific specialties and research organizations that are relevant to current issues involving forest management and conservation. Specific areas of research in need of increased funding and attention include the following: the relationship of natural disturbances to the sustainability of protected and managed Pacific Northwest forests and the extent to which the effects of these disturbances can be simulated by management practices; the relative importance of legacies and their role in maintaining forests and regenerating harvested areas, and the extent to which management actions can "create" legacies; the role of insects and pathogens in sustaining natural processes in Pacific Northwest forests and factors involved in insect and pathogen outbreaks in the region; forest restoration methods and their role in restoring and main- taining forest vitality; the impacts of forest-management practices, including timber harvesting, on the production of nonwood forest products, including recreation and special forest products such as wild-grown mushrooms; information for making accurate assessments of the impacts of changes in forest practices on regional and local employment and income;

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74 Pacific Northwest Forests impacts of changes in forest practices In the Pacific Northwest on biological and nonbiological factors within the region and in other affected regions; continued basic research on the biological functioning and interactions of the multitude of life forms present in the Pacific North- west forests. The importance of adequate research funding to develop these kinds of information is shown by the duration and intensity of the conflict over the management of Pacific Northwest forests. Much of the conflict has been over differing views of what is happening to the forests and has been basecE in most cases on poor or insufficient information. The cost of the conflict and the turmoil it brought to the region has been substantial. At the risk of seeming to be unduly sanguine, the commit- tee believes that attention to developing an appropriate information base will help to resolve similar issues in the future.