John Cissel
Research Coordinator
Willamette National Forest
Blue River Ranger District
PO Box 100
Blue River, OR 97413

cissel@fsl.orst.edu
jcisse@fs.fed.us

541 822-1214

Fred Swanson
Ecosystem Team Leader
Pacific Northwest Research Station
Forestry Sciences Laboratory
Corvallis, OR 97331

frederick.swanson@orst.edu
fswanson@fs.fed.us

541 750-7355

A team of scientists and managers based on the H.J. Andrews Experimental Forest and the Blue River Ranger District of the Willamette National Forest have been working together for most of this decade to develop and test a landscape management approach based on natural disturbance regimes. The team has been motivated to a significant degree by concern over the loss and fragmentation of older forests, and the lack of a coherent long-term strategy for conservation of older forests in managed landscapes. The underlying assumption of this approach is that by approximating key aspects of important disturbance regimes in management regimes risks posed to native species and ecological processes are reduced as compared to other historical and contemporary landscape management approaches (Swanson et al. 1994).

Concepts concerning use of information about natural disturbance regimes in management activities are emerging in many forest landscapes (Baker 1992, Hunter 1993, Mladenoff et al. 1993, Morgan et al. 1994, Swanson et al. 1994, Bunnell 1995, Stuart-Smith and Hebert 1996, Cissel et al. 1998, Cissel et al. 1999, Landres et al. 1999). These approaches use information on historical and current landscape conditions, disturbance history, and social goals to set objectives for future landscape structures that provide desired habitat, watershed, timber supply, and other functions. The intent is not to mimic natural conditions, but rather to use them as a reference in developing and evaluating management alternatives to meet these goals.

The study includes the entire Blue River drainage (approximately 23,000 hectares), a tributary watershed of the McKenzie River basin.

The landscape is steep, highly-dissected, volcanic terrain of the Cascade Range. Annual precipitation exceeds 2500 mm which falls mostly in October-April as rain at lower elevation and snow in higher areas. The landscape ranges from 317 m (1040 ft) to 1639 m (5349 ft) in elevation largely covered by conifer forests dominated by Douglas-fir (Pseudotsuga menziesii), western hemlock (Tsuga heterophylla), and Pacific silver fir (Abies amabalis). The majority of these natural forests have developed after wildfire 60-150 yrs and 400-500 yrs before present. Cutting in the Andrews Forest in 1950-1970 and in the rest of Blue River mainly in 1960-1990 has created scattered conifer plantations and other early-successional vegetation patches.

The Blue River watershed is a part of the Central Cascades Adaptive Management Area, an allocation in the Northwest Forest Plan that encourages development and evaluation of new approaches. The H.J. Andrews Experimental Forest (approximately 6,300 hectares), established in 1948, is located entirely within the Blue River watershed.

The overriding objectives given to the Central Cascades Adaptive Management Area in the Northwest Forest Plan are to conduct "intensive research on ecosystem and landscape processes and its application to forest management in experiments and demonstrations at the stand and watershed level", and to develop "approaches for integrating forest and stream management objectives and on implications of natural disturbance regimes" (USDA and USDI 1994). The Blue River Landscape Study is specifically designed to develop, test and modify a landscape management approach based on natural disturbance regimes using an adaptive management model. Integration of forest and stream management objectives is also a strong and complementary theme of the study. The landscape management approach used in the study is intended to meet the same general objectives underlying the Northwest Forest Plan: provide habitat to sustain species associated with late-successional forests, maintain and restore aquatic ecosystems, and provide a sustainable supply of timber.

The adaptive management model followed in this study consists of three phases:

The first phase, the assessment phase, employs multiple modes of learning to discover the potential effects of managing under this concept. These findings are evaluated in the second phase to determine their significance and implications. Adjustments to the landscape management strategy are made in the third phase based on the information produced from the preceding phases, and other sources of new concepts or information.

Four primary methods are used to assess the effects of the landscape management plan. The plan is being implemented on the ground through normal Forest Service programs. Novel aspects of the plan challenge ranger district employees to think differently and try new approaches. Hence operational experience is a key mode of learning and a true testing ground. Field-based monitoring efforts are a second major mode of learning. Permanent plots are in place to measure the effects of plan implementation on a variety of species and ecological processes. However, it may take decades before many effects are observable and their significance known. Meanwhile a series of modeling assessments are being conducted to provide preliminary results. A fourth method of learning derives from the H.J. Andrews Experimental Forest research program. Applicable research projects conducted in the watershed are designed to help understand patterns and processes directly relevant to the landscape management approach in the study.

Findings are evaluated through information exchange with interested parties, and through workshops and reports focused on evaluation. Results from phase one are shared with a wide variety of audiences through field tours, informal and formal reports, web sites, presentations and open houses. Feedback obtained directly from managers, policy-makers and interest groups through personal interaction is an important means of evaluation. Results from phase one are also evaluated through analysis and written reports (e.g., Weisberg 1999, on file at the Blue River Ranger District), and through adaptive management workshops and field tours. The principle result from these efforts are recommendations for potential changes to the landscape plan or to the assessment projects.

The landscape management plan will be periodically revised when these results indicate a potential benefit to doing so. We have not yet been through this phase, but envision that recommendations will also be shared widely with involved individuals to gain further perspective on the desirability of making changes to the study. Forest Service managers and scientists responsible for conduct of the landscape study will make the final decisions concerning changes to the study.

Two primary sources of information support much of the landscape management strategy. Earlier work in the Augusta Creek landscape planning area (Cissel et al. 1998), where many of these concepts were pioneered, demonstrated the importance of understanding natural disturbance regimes. Fire has played a central role in shaping historical landscapes in this part of the Cascade Range. Fire history information from previous studies in the area (Teensma 1987, Morrison and Swanson 1990) and from new data were complied in "Blue River Fire Regime Analysis and Description" (Weisberg 1996, on file at the Blue River Ranger District office). Data and supporting maps from this report provided descriptions of general fire regimes in the Blue River watershed. A watershed analysis was conducted following procedures in the Federal Guide to Watershed Analysis (USDA Forest Service 1996, on file at the Blue River Ranger District office) to describe and document hillslope-to-stream disturbance processes across the watershed. Other important information sources included "Herpetofauna in the Blue River Watershed, Western Cascades, Oregon" (Hunter 1996, on file at the Blue River Ranger District office), and data on spotted owl productivity within the watershed from the spotted owl demography study (data on file at Blue River Ranger District).

Two types of reserves were established. First, "Special Area Reserves" allocated in the Willamette National Forest Plan (USDA 1990), as amended by the Northwest Forest Plan, were delineated. These include Special Interest Areas, Late-Successional Reserves, and the H.J. Andrews Experimental Forest. In addition, "Aquatic Reserves" were established to help meet the aquatic ecosystem objectives in the Northwest Forest Plan would be met. These reserves are of two types: small-watershed reserves and corridor reserves. Small-watershed reserves are strategically located throughout the watershed to encompass areas of particular importance to aquatic ecosystems and spotted owls. In addition, corridor reserves are established on all fish-bearing streams. Objectives for these reserves are to generally allow natural succession to occur, except where experiments are being conducted in the Andrews Experimental Forest, or late-successional habitat can be enhanced through management activities in young stands.

The remainder of the watershed is subdivided into three areas, termed "Landscape Areas", based on the natural fire regime interpreted for each area. Historically, fire frequency, severity, and spatial pattern varied across the watershed. Wetter, cooler sites experienced infrequent severe fires and warmer, drier sites experienced more frequent lower severity fires. For each landscape area, timber harvest and fire prescriptions were based on the underlying fire regime, as interpreted from tree-ring records. Timber harvest frequency and rotation age (100 - 260 years) were based upon historical fire frequency, timber harvest intensity (15% - 50% overstory retention) was based upon historical fire severity, and the spatial patterns of timber harvest were based upon the spatial patterns of historical fires. The apparent pattern of historical fire in the watershed was quite variable (Weisberg 1996). Landscape areas were intended to reflect that variability across the watershed rather than represent a precise fit at an individual site. Fire prescriptions are integrated with the timber harvest prescriptions. Implementation guidelines are intended to reflect natural disturbance patterns to the extent feasible while protecting ecological values. Figure 3 depicts a plan view of both the landscape management plan ("Landscape Plan") and a literal implementation of the Northwest Forest Plan as if it were applied to the Blue River watershed ("Interim Plan"). Future timber harvest and forest successional patterns were projected across the watershed for the next 200 years for both plans (Figure 4).

Figure 3. Management areas for the Blue River Watershed managed under matrix and riparian reserve designations in the Northwest Florest Plan (termed "Interim Plan"), and for the Blue River landscape management strategy (termed "Landscape Plan").

Figure 4. Projected future landscape structures for the Blue River landscape management strategy (termed "Landscape Plan"), and for the Blue River watershed managed under matrix and riparian reserve designations in the Northwest Forest Plan (termed "Interim Plan").

Watershed restoration activities are intended to reestablish a resilient, interconnected aquatic network capable of maintaining aquatic habitats and processes while management activities are occurring in the watershed. Development of a spatially- and temporally-specific schedule of future timber harvest activities allowed for integrated planning and better attainment of restoration goals. For example, two sub-watersheds are planned as long-term restoration areas while timber sale regeneration harvests are planned elsewhere in the watershed. Restoration activities underway or in the planning stage include addition of large wood to stream channels, encouraging growth of large conifers near streams, improvement of road drainages, decommissioning roads while re-establishing stream channels, and removal of human-placed fish migration barriers. Noxious plant removal is targeted to specific areas where there is a reasonable likelihood of success.

Patterns of habitats across space and time have been assessed for both the landscape plan and the interim plan. Results show that the landscape plan will produce more late-successional habitat (71% of the watershed versus 59%) in a less fragmented landscape as compared to the interim plan (Cissel et al. 1999). The landscape plan is characterized by larger patches, more interior habitat, and less edge between old and young forests. In addition, the landscape plan contains more complex stand structures due to generally higher overstory retention levels, and maintains a substantial component of mature forest. In contrast, the interim plan nearly eliminates the mature forest component because almost all lands are either in a reserve, where all lands grow old and large-scale disturbance is eliminated, or in matrix lands where a relatively short rotation (approximately 80 years) prevents regrowth of mature forest. We feel that the absence of mature forest in the interim plan poses substantial risk when mortality due to disturbance, climate change or senescence eliminates older Douglas-firs in the reserves. Additional analyses are underway to evaluate lichen communities, future stand structures, timber volume and economics.

A long-term, multi-scale monitoring plan is being implemented to evaluate the effectiveness of the landscape management plan. Some of the monitoring projects are continuing long-term monitoring associated with the Andrews Experimental Forest, others have been recently initiated. The monitoring framework is organized along a hierarchy of spatial scales.

Landscape structures resulting from both the landscape management plan in this study and from the interim plan are historically unprecedented. For that reason we feel it is critical that an adaptive management approach be followed for both approaches. We are pressing ahead with implementation, monitoring, modeling, and research to better define and evaluate a historically-rooted approach in the Blue River watershed based on the landscape dynamics inherent to the area. We hope these concepts can be tested in other provinces in the region, and that the matrix and riparian reserve approach of the interim plan can also be similarly tested.

Baker, W. L. 1992. The landscape ecology of large disturbances in the design and management of nature reserves. Landscape Ecology 7:181-194.

Bunnell, F. L. 1995. Forest dwelling vertebrate faunas and natural fire regimes in British Columbia: patterns and implications for conservation. Conservation Biology 9:636-644.

Cissel, J. H.; F. J. Swanson; G. E. Grant; D. H. Olson; S. V. Gregory; S. L. Garman; L. R. Ashkenas; M. G. Hunter; J. N. Kertis; J. H. Mayo; M. D. McSwain; S. G. Swetland; K. A. Swindle; and D. O. Wallin. 1998. A landscape plan based on historical fire regimes for a managed forest ecosystem: the Augusta Creek study. USDA Forest Service General Technical Report PNW-GTR-422. Pacific Northwest Research Station, Portland, Oregon, USA.

Cissel, J. H.; F. J. Swanson; and P. J. Weisberg. 1999. Landscape management using historical fire regimes: Blue River, Oregon. Ecological Applications 9(4):183-198.

Hunter, M. L. Jr. 1993. Natural fire regimes as spatial models for managing boreal forests. Biological Conservation 65:115-120.

Landres, P. B.; P. Morgan; and F. J. Swanson. 1999. Overview of the use of natural variability concepts in managing ecological systems. Ecological Applications 9(4):xxx.

Mladenoff, D. J. ; M. A. White; J. Pastor; and T. R. Crow. 1993. Comparing spatial pattern in unaltered old-growth and disturbed forest landscapes. Ecological Applications 3:294-306.

Morgan, P.; G. H. Aplet;, J. B. Haufler; H. C. Humphries; M. M. Moore; and W. D. Wilson. 1994. Historical range of variability: a useful tool for evaluating ecosystem change. Journal of Sustainable Forestry 2:87-111.

Morrison, P.; and F. J. Swanson. 1990. Fire history and pattern in a Cascade Range landscape. USDA For. Serv. Gen. Tech. Rep. PNW-GTR-254.

Stuart-Smith, K.; and D. Hebert. 1996. Putting sustainable forestry into practice at Alberta Pacific. Canadian Forest Industries April/May:57-60.

Swanson, F. J.; J. A. Jones; D. O. Wallin; and J. H. Cissel. 1994. Natural variability - implications for ecosystem management. Pages 89-106 in M. E. Jensen, and P. S. Bourgeron. technical editors. Eastside forest ecosystem health assessment - Volume II: ecosystem management: principles and applications. USDA Forest Service General Technical Report PNW-GTR-318. Pacific Northwest Research Station, Portland, Oregon, USA.

Teensma, P.D.A. 1987. Fire history and fire regimes of the Central Western Cascades of Oregon. Ph.D. Dissertation, Univ. of Oregon, Eugene.

USDA Forest Service. 1990. Land and resource management plan, Willamette National Forest. Willamette National Forest, Eugene, OR.

USDA Forest Service; and USDI Bureau of Land Management. 1994. Record of decision for amendments for Forest Service and Bureau of Land Management planning documents within the range of the northern spotted owl. USDA For. Serv. and USDI Bur. Land Manage. 74 p.