A REVIEW AND SYNTHESIS OF AVAILABLE INFORMATION ON RIPARIAN DISTURBANCE REGIMES IN EASTERN WASHINGTON
Submitted to: STATE OF W ASHINGTON
DEPARTMENT OF NATURAL RESOURCES
January 2003
PSC 02-127
Prepared by:
5780 West Werner Road Bremerton, WA 98312
LIMITATIONS
This document is a deliverable to the State of Washington Department of Natural Resources required under Personal Services Contract (Contract No. PSC 02-127) “A Review and Synthesis of Available Information on Riparian Disturbance Regimes in Eastern Washington.”
This deliverable represents Concurrent Technology Corporation’s (CTC’s) best effort within the available resources and is prepared using the standards of practice for professional services and in accordance with the standards of the technical professions represented. This document is intended for the use of CTC and its client.
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ACKNOWLEDGEMENTS
The following people are gratefully acknowledged for their invaluable contributions to this report.
Technical Leads:
Richard L. Everett Concurrent Technologies Corporation James P. Dobrowolski Washington State University
Literature and Information Contributions:
James Agee University of Washington John Beebe Tufts University Susan Bolton University of Washington Sondra Collins Upper Columbia United Tribes Wallace Covington Northern Arizona University Carl Davis Wenatchee National Forest Fred Ebil Society of American Foresters Greg Filip Oregon State University Paul Flanagan U.S. Department of Agriculture Forest Service Domoni Glass Cooperative Monitoring, Evaluation, and Research Committee Scientific Advisory Group Eastside Co-Chair Jan Hemstrom U.S. Department of Agriculture Forest Service Jan Henderson U.S. Department of Agriculture Forest Service Larry Irwin National Council for Air and Stream Improvement, Incorporated Bud Kovalchik U.S. Department of Agriculture Forest Service (retired) Jeff Light Plum Creek Timber Terry Lillybridge U.S. Department of Agriculture Forest Service Geoffrey McNaughton Washington State Department of Natural Resources Shari Miller U.S. Department of Agriculture Forest Service Ron Neilson Oregon State University Pete Ohlson U.S. Department of Agriculture Forest Service Wayne Padgett U.S. Department of Agriculture Forest Service Blake Rowe Longview Fibre Brion Salter U.S. Department of Agriculture Forest Service Craig Schmitt U.S. Department of Agriculture Forest Service Don Scott U.S. Department of Agriculture Forest Service Duane Vaagen Vaagen Brothers Lumber Incorporated Maurice Williams Cooperative Monitoring, Evaluation, and Research Committee Scientific Advisory Group Eastside Co-Chair Andy Youngblood U.S. Department of Agriculture Forest Service Darlene Zabowskii University of Washington
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EXECUTIVE SUMMARY This scoping document presents an evaluation of the current level of knowledge about historical and current disturbance regimes and vegetation responses in riparian and adjacent upslope forests in Eastern Washington based on a sample of scientific literature characteristic of the total available information. Sampled literature was used to address seventeen questions concerning the ecology and management of riparian forests posed by the Cooperative Monitoring, Evaluation, and Research Committee (CMER) Scientific Advisory Group Eastside (SAGE). Information gaps that prevented or limited the response to the questions are identified along with recommendations for future research.
In addition to addressing the questions posed by CMER SAGE, this report contains an annotated bibliography and a brief summary of two Forest Dynamics Workshops sponsored by the Eastside Riparian Scientific Advisory Group (ERSAG) (now CMER SAGE). The annotated bibliography provides information, limited detail in some instances, and annotations for the literature assembled to address the questions.
Despite a very large information base on historical and current disturbance regimes within Eastern Washington forests, differences in riparian and upslope disturbance regimes and post-disturbance responses are not well known. Both historically and currently, there is limited regional-scale information on what portions of the landscape are most affected by disturbance. Much of the scientific literature describing Eastern Washington disturbance regimes and vegetation responses is at the forest series or plant association group level and does not distinguish between riparian and upslope communities. Available information has frequently been extrapolated from point observations and limited-spatial area studies or inferred from available information on historical stand characteristics. The differences between current and historical disturbance regimes for fire are better defined than for insects, pathogens, and other disturbance types.
No clear consensus exists on whether there is a difference between disturbance regimes and vegetation responses of riparian and upslope areas. In fact, available information on riparian ecosystem disturbance regimes and responses was often contradictory. Riparian ecosystems are recognized as corridors of disturbance and are considered both sensitive to and products of drastic disturbance. The effects of disturbance may be of sufficient magnitude to redirect successional paths.
The likelihood of duplicating historical disturbance regimes to reestablish historical forest conditions is low given current forest stand conditions and global climate change. Knowledge of disturbance regimes and vegetation responses supports prediction of post- disturbance response and allows for the revision of forest practices under an adaptive management strategy. Available information indicates that a dynamic approach to management – one that constantly monitors changes in resource conditions – is required. Recently developed models (e.g., FIRESUM) and geographic information system (GIS) tools may be used to assess and integrate information and data. Additional research aimed at regional-scale forest stand disturbance processes is recommended to supplement existing data and better define the role of disturbance in riparian and upslope forest habitats.
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TABLE OF CONTENTS SUMMARY REPORT ...... 1 Introduction ...... 3 The Ecological Setting ...... 5 Ecoregions of Eastern Washington...... 6 Ecological Reporting Units ...... 7 Ecoregion Variability ...... 8 Key Concepts ...... 9 Ecological Riparian Communities and Regulatory Riparian Zones ...... 10 Variability Within F&FR Forest Types ...... 12 Historical Reference Conditions ...... 20 Questions ...... 23 Question 1 ...... 23 Question 2 ...... 27 Question 3 ...... 30 Question 4 ...... 33 Question 5 ...... 39 Question 6 ...... 41 Question 7 ...... 44 Question 8 ...... 48 Question 10 ...... 52 Question 11 ...... 54 Question 12 ...... 58 Question 14 ...... 64 Question 15 ...... 67 Question 16 ...... 70 Question 17 ...... 71 Data Gaps and Recommendations ...... 75 General Data Gap ...... 75 Question-Specific Data Gaps ...... 75 WORKSHOP SUMMARIES and ANNOTATED BIBLIOGRAPHY ...... 79 Workshop Summaries ...... 81 Eastside Forest Dynamic Workshops ...... 81 Forest Dynamic Workshop in Spokane, February 22, 2001 ...... 82 Dynamic Forest Workshop in Ellensburg, May 22, 2001 ...... 85 Annotated Bibliography ...... 89 Background ...... 89 Highly Relevant Summary Documents ...... 9291 Highly Relevant Studies ...... 108107 Other Highly Relevant References ...... 128127 Relevant Summary Documents ...... 137136 Relevant Studies ...... 154153 Supporting Summary Documents ...... 181180 Supporting Studies ...... 207206 General References ...... 220219 Other Works Cited ...... 222221
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LIST OF TABLES Table 1. Wenatchee National Forest Land Area and Percent of Area by Forest Series...... 16 Table 2. Forest and Fish Regulation Elevation Zones and Forest Habitat Types in Relation to Distribution Limits of Riparian Forest Series in Eastern Washington ...... 17 Table 3. Riparian Forest Series Present in Forest and Fish Regulation Designated Elevation Zones and Forest Habitat Types ...... 18 Table 4. Fire Regimes for Eastside Forest Series ...... 25
LIST OF FIGURES Figure 1. Ecological Reporting Units in Eastern Washington ...... 7 Figure 2. Forest Type Composition of the Forest and Fish Regulation Forest Habitat Types by Elevation Zones ...... 14 Figure 3. Vegetation by Elevation Band in the Wenatchee National Forest ...... 15
APPENDICES Appendix A. Professional Contacts List ...... 230229 Appendix B. Spokane Forest Dynamic Workshop Transcribed Text ...... 234233
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ACRONYMS AND ABBREVIATIONS ABAM Pacific Silver Fir Series ABGR Grand Fir Series ABLA2 Subalpine Fir Series ACCI-WEN Vine Maple - Wenatchee ACTR Deerfoot Vanillaleaf Series ACTR-WEN Deerfoot Vanillaleaf Series - Wenatchee ARNU (ARNU3) Wild Sarsaparilla Series ATFI Lady-Fern Series BP before present CASCP2 Saw-Leaved Sedge Series CD-ROM compact disc-read only memory cm centimeter(s) CMER Cooperative Monitoring, Evaluation, and Research Committee COCA Bunchberry Dogwood Series COD coarse organic debris CLUN Queencup Beadlily Series CRBSUM Columbia River Basin Succession Model CTC Concurrent Technologies Corporation dbh diameter breast height DNR Department of Natural Resources EQUIS Horsetail Series ERSAG Eastside Riparian Scientific Advisory Group ERU ecological reporting unit F&FR Forests and Fish Regulations FEMAT Forest Ecosystem Management Assessment Team FFI fire frequency interval FFP fire free period GCM general circulation model GIS geographic information system GYDR Oak-Fern Series HRV historical range of variability ICBEMP Interior Columbia Basin Ecosystem Management Project LALY Subalpine Larch Series LOD large organic debris
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LWD large woody debris np not present ODF Oregon Department of Forestry OPHO Devil's Club Series PAG plant association group PICO Lodgepole Pine Series PIEN Engelmann Spruce Series PIPO Ponderosa Pine Series POTR Quaking Aspen Series POTR2 Black Cottonwood Series PSME Douglas-Fir Series RHAL Cascade Azalea Series RMZ riparian management zone RSAG Riparian Scientific Advisory Group SAGE Scientific Advisory Group Eastside SDI stand density index SMZ streamside management zone spp. species SPZ stream protection zone SSR seasonal severity rating SYAL Common Snowberry Series TELSA Tool for Exploratory Landscape Scenario Analyses THPL Western Red Cedar Series TRLA4 Globeflower Series TSHE Western Hemlock Series TSME Mountain Hemlock Series UCUT Upper Columbia United Tribes USFS United States Forest Service VAME Big Huckleberry Series WMPIs Weibull median probability fire return intervals
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PART 1
SUMMARY REPORT
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Section
1.0
2Section.0 Introduction
This document presents scientific information available on forest disturbance regimes and vegetation responses in riparian and adjacent upslope forests of Eastern Washington. Available information was used to address seventeen questions on the ecology and management of riparian forests posed by the Cooperative Monitoring, Evaluation, and Research Committee (CMER) Scientific Advisory Group Eastside (SAGE). The questions are a subset of the CMER L-1 list of questions designed to evaluate the scientific merits of existing Forests and Fish Regulations (F&FR) (Washington State Department of Natural Resources 2001).
The seventeen questions posed by CMER SAGE contain topics on:
• Fire, insect, pathogen, and drought disturbance. • Vegetation response to disturbance by forest type in upland and riparian communities. • Forest type distribution by elevation zone. • Influence of elevation on disturbance regimes. • Historical versus current forest conditions and disturbance regimes. • Thinning of thick stands as it relates to drought, forest pests, and other disturbances. • Applicability of current F&FR riparian basal area standards using historical or current disturbance regimes and current reference stand conditions.
Several of these topics occur in any one question and multiple questions share many of the same topics (see Part 1, Section 4.0).
As per direction from CMER SAGE, this report is specific to information available on these topics from research and administrative studies conducted in Eastern Washington. When there was a dearth of information, the Concurrent Technologies Corporation (CTC) project team used published information from throughout the Cascade and Rocky Mountain Ecoregion Provinces (Bailey 1995) that contain the Eastern Washington forest types. With the need to expand the geographic base to address some questions, the amount of scientific material increased significantly and the literature review, of necessity, became representative rather than all-inclusive. This document is not presented as a scientific summary of all the literature available on each of the topics raised in the seventeen questions.
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The CTC project team queried literature databases, conducted literature searches at the University of Washington and Washington State University, and contacted scientists and resource specialists for scientific information on the subject of each of the questions (see Appendix A). An annotated bibliography of the scientific materials used in addressing the questions is provided.
This report addresses each of the seventeen questions and provides a summary of disturbance regimes and riparian forest response in Eastern Washington forest types. Information gaps that prevented or limited the response to the questions and fruitful areas of research are identified.
The remainder of this report is organized as follows:
• Part 1, Summary Report
♦ Section 2.0, The Ecological Setting: introduces ecological region divisions found in Eastern Washington and provides an example illustrating the ecological variability within a single ecological region.
♦ Section 3.0, Key Concepts: discusses significant terms and issues related to the seventeen questions.
♦ Section 4.0, Questions: presents the CMER SAGE questions and the CTC project team’s responses.
♦ Section 5.0, Data Gaps and Recommendations: presents identified data gaps and suggests possible ways of filling those gaps. • Part 2, Workshop Summaries and Annotated Bibliography
♦ Section 1.0, Workshop Summaries: presents a brief summary of two Eastside Forest Dynamic Workshops sponsored by the Eastside Riparian Scientific Advisory Group (ERSAG) (now CMER SAGE).
♦ Section 2.0, Annotated Bibliography: presents categorized references identified as part of this effort that relate to riparian disturbance regimes and vegetation responses. • Part3, Appendices: provides a list of contacts and transcribed text from one of the Eastside Forest Dynamic Workshops.
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Section 2.0
The Ecological Setting
Eastern Washington, as delineated by the F&FR, is an ecologically variable area with multiple ecological conditions represented, a fact that should be considered when managing Eastern Washington forests. The ecological setting in Eastern Washington has been defined by Bailey (1995) as consisting of ecoregions and by the Interior Columbia Basin Ecosystem Management Project (ICBEMP) (1995) as consisting of ecological reporting units (ERUs). Within these relatively large ecological regions a variety of ecological conditions exist. This ecological variability within an ecological region is directly related to local geology, climate, and vegetation. An example demonstrating this ecological variability is presented.
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Ecoregions of Eastern Washington
Four ecoregions as defined by Bailey occur in Eastern Washington: Cascade Province, Northern Rocky Mountain Province, Middle Rocky Mountain Province, and Intermountain Semidesert Province (1995). Eastern Washington forests occur in all but the Intermountain Semidesert Province. The ecoregions are defined by climatic patterns, topography, landforms, soil, and vegetation (Bailey 1995).
The Cascade Province of Washington is steep and highly dissected with narrow valley bottoms except where glaciated. Ranging from sea level to elevations above 5,000 feet, the province has a maritime climate with annual precipitation declining rapidly from 380 centimeters (cm) at the crest to 51 cm at the eastern slope foothills. The forest transitions from mountain hemlock, western hemlock, pacific silver fir, whitebark pine, subalpine larch, subalpine fir, Engelmann spruce, noble fir, grand-fir, Douglas-fir, western larch, and ponderosa pine from the crest to lower eastside elevations. Soils include erosive, unconsolidated volcanic ash.
The Northern Rocky Mountain Forest Province is characterized by steep mountains with elevations ranging up to more than 9,000 feet and a broad valley between. The climate is a mix of maritime and continental with annual precipitation ranging from 51 to 102 cm. Forests are dominated by Douglas-fir, western hemlock, western red cedar, western larch, grand fir, and ponderosa pine. The historical presence of western white pine is missing because of mortality from white pine blister rust. Soils in the mountains are cool and moist and are skeletal in nature.
The Blue Mountains of Eastern Washington fall within the Middle Rocky Mountain Province. Elevations within the province range from 3,000 to 7,000 feet. These uplifted basalts have a maritime climate with significant continental influence and approximately 77 cm of annual precipitation. This province includes Douglas-fir dominant forests. Grand fir, lodgepole pine, and ponderosa pine are also present.
Non-forested areas of Eastern Washington are within the Intermountain Semidesert Province. In Eastern Washington, the Columbia Plateau at approximately 3,000 feet above sea level represents this province. The dry climate of this province supports sagebrush and dry grassland vegetation.
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Ecological Reporting Units
To be consistent with the most recent ecological assessment of these Eastern Washington forests (ICBEMP 1999), the three forest provinces are further defined as the Northern Cascades Ecological Reporting Unit (ERU), the Northern Glaciated Mountains ERU, and the Blue Mountains ERU (see Figure 1).
Figure 1. Ecological Reporting Units in Eastern Washington (Adapted from Hessburg et al. 1999)
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Ecoregion Variability
An example of the diverse geology, climate, and vegetation on the Wenatchee National Forest (the southern portion of the Northern Cascades Province and the Northern Cascades ERU) highlights the potential variability within an ecoregion or ERU (Lillybridge et al. 1995). The Wenatchee National Forest is divided into three ecological regions based on geology and climate patterns. One ecological region is known as the “Chelan Terrain.” It extends from the Entiat Fault to the Methow Valley. The mountains in this region are relatively higher, steeper, more rugged, and wider than the other two ecological regions in the Wenatchee National Forest. The region is affected by a strong rain shadow from the Cascade Mountains with extended dry periods during summers. Xeric and cold forest types predominate. Douglas-fir, subalpine fir, and ponderosa pine are the climax species with subalpine larch and whitebark pine near the timberline. Silver fir and mountain hemlock are present in narrow maritime zones extending only a few miles eastward along major east-west ridges and drainages. Lodgepole pine and Engelmann spruce are present in significant numbers, but more mesic species such as western hemlock, western red cedar, western larch, and grand fir are less common and may be absent.
South of the Entiat Fault to approximately the Yakima River and Ellensburg lies the second ecological region within the Wenatchee National Forest. The geology of this region is highly diverse, with most of the region lying outside the area affected by the continental ice sheet. Slopes are steep and long. Elevation in this region is low with relatively narrow mountain ranges. As a result, the rain shadow effect from the Cascades is lessened, allowing more mesic forests of Pacific silver fir, western hemlock, or grand fir to exist than in forests to the north. Species present in this region include ponderosa pine, Douglas-fir, grand fir, and subalpine fir on the relatively drier eastside of this region with Pacific silver fir, mountain hemlock, western hemlock, and western red cedar in the maritime areas to the west. As in the region described above, subalpine larch and whitebark pine form forests near the timberline. Other prominent species include lodgepole pine, western larch, and Engelmann spruce.
The third ecological region in the Wenatchee National Forest extends from Ellensburg to the Yakima Indian Reservation. Although no continental glaciation occurred in this region, mountain glaciation is widespread, and volcanic deposits are present. Elevations are relatively low with the exception of the areas near volcanoes. This region has a broad range of climatic conditions, with more mesic forests present than in either of the previously described regions. Major forest zones include ponderosa pine, Douglas-fir, grand fir, and subalpine fir to the more xeric east with Pacific silver fir, mountain hemlock, Alaska yellow cedar, western hemlock, and western red cedar in the more mesic, maritime west. Unlike the other regions, near timberline forests do not contain subalpine larch; whitebark pine is present near the timberline. Lodgepole pine and Engelmann spruce are present.
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Section 3.0 Key Concepts
Responses to each of the seventeen questions posed by CMER SAGE contribute to the evaluation of the F&FR use of forest habitat types, elevation zones, and disturbance management. To establish a baseline understanding of terms used in the seventeen questions, this section presents discussions of the following topics:
• Ecological riparian communities and regulatory riparian zones. • Variability within F&FR forest types. • Historical reference conditions.
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Ecological Riparian Communities and Regulatory Riparian Zones
Regulatory-defined riparian zones do not consistently delineate ecological riparian communities. A regulatory-defined riparian buffer, may, by necessity, greatly exceed the ecological riparian boundary to protect aquatic systems from vegetation management activities. Streams and rivers are the riparian systems considered in this discussion since they represent the majority of the land/water interfaces found on forested lands in the Pacific Northwest (Oakley et al. 1985). Ecological Riparian Communities Riparian communities are, functionally, wetland communities and have been defined as the point where shrubby vegetation no longer interacts with the stream (Campbell and Franklin 1979). In riparian forests, the soil is usually mesic or wet, and a fluvial floodplain is formed by coarse textured debris with or without organic soil, while the upland has deep organic soils that are slightly dry to moderately moist. Species composition, moisture availability, physiognomy, and disturbance regime distinguish riparian communities from adjacent uplands (Brinson 1990, Naiman et al. 1992).
In the mid-1980s, Oregon’s Riparian Task Force established a more structured definition of riparian ecosystems with three distinct zones. An “aquatic zone” is the wetted area of streams, lakes, and wetlands up to the average high water mark. The “riparian zone” includes terrestrial areas where the vegetation and microclimate are affected by water either intermittently or continually and are typically associated with high water tables and hydric soils. A “riparian zone of influence” is transitional between the riparian zone and the upland vegetation. Trees and shrubs form the outer edge of the riparian ecosystem in this zone, characterized by a change in plant composition, relative plant abundance, and the end of high soil moisture (Raedeke 1988). This zone contains woody vegetation that provides shade, organic material (fine and coarse), and terrestrial insects (Carleson and Wilson 1985).
The terrestrial system may influence the aquatic zone by dictating the stream channel form, controlling material passing through the system, and providing a primary source of energy and nutrient inputs to the channel (Bilby 1988). The mosaic of riparian vegetation reflects a complex interaction among geomorphic processes, vegetation, and time (Johnson et al. 2000). Recent studies of the effects of edges along riparian areas on microclimate conditions into the adjoining forest (Chen et al. 1995, Brosofske et al. 1997, Dong et al. 1998) found changes in microclimates extending well beyond the width of the riparian areas (Hibbs and Bower 2001).
Riparian systems are products of several types of disturbances interacting at variable frequencies and magnitudes within a varying but generally moist zone, producing plant communities that have generally higher species richness and a more diverse structure than uplands (Agee 1988). Riparian ecosystems generally serve to dissipate water and wind energy that can damage lowlands, often acting as natural windbreaks in moisture-limited systems (Hansen et al. 1995).
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Regulatory Riparian Zones Riparian zones are often defined in a regulatory sense as the area within some arbitrary distance from the channel edge and may include forest or shrub communities as well as the distinct riparian community. A riparian buffer is often applied to a variety of regulatory- designated protection zones managed by state and federal agencies, including Idaho’s Stream Protection Zone (SPZ), Washington’s Riparian Management Zone (RMZ), and the U.S. Forest Service’s Streamside Management Zone (SMZ). These regulatory-defined terms all describe riparian zones where forest practices are restricted by regulatory or legislative requirements (Belt et al. 1992). The State of Washington Department of Natural Resources has defined regulatory riparian zones since 1967 as leave strips 10 to 300 feet wide (Calhoun 1988). The Yakima Tribe has established regulatory riparian buffers on every stream with widths (66 to 330 feet) that often extend beyond the limits of the riparian vegetation (Bradley 1988). These riparian zones, although regulatory-assigned, are still dynamic resources changing in time and space with the dynamics of stream hydraulics and flow that eventually sculpt the structure and composition of the vegetation, soil, and channel profile (Pedersen 1988).
Multiple approaches to establishing riparian buffer criteria have been used or proposed. Pacific Northwest states have attempted to establish multiple riparian buffer criteria that are simply stated as separate requirements, such as width and number of leave trees. Other approaches to defining and implementing buffers included a cartographic approach (Dick 1991), which combined a spatial model with a geographic information system (GIS) using a single criterion such as temperature moderation. Another maximum protection approach evaluates each of several criteria in terms of buffer width and then adopts the greatest width to accommodate all of the criteria. A third more regional method to establish buffer strip widths was based on a regional analysis of selected stream reaches within the region. In a region where fisheries were a major concern, shade and large organic debris (LOD) recruitment might be used as criteria for buffer width determination (Belt et al. 1992).
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Variability Within F&FR Forest Types
Much of the scientific literature describing Eastern Washington disturbance regimes and vegetation responses is at the forest series or plant association group (PAG) level. The F&FR defines forest habitat types based on three elevation zones (0 to 2,500 feet - ponderosa pine habitat type, 2,500 to 5,000 feet - mixed conifer habitat type, and greater than 5,000 feet - high elevation habitat type). While there is some evidence that indicates that elevation may serve as a surrogate for moisture and temperature in defining vegetation distribution, forest series or PAGs do not correspond consistently to elevation or to F&FR forest habitat types. Variability within elevation bands, F&FR habitat types, and forest series can be significant. Additionally, available scientific literature describing Eastern Washington disturbance regimes and vegetation responses does not correspond to these F&FR habitat types or to elevation zones. Elevation as a Surrogate for Moisture and Temperature in Defining Vegetation Distribution Topographic features that interact to influence species composition and structure of plant communities are elevation, aspect, and slope steepness (Perry 1995). The three F&FR elevation zones can be useful tools to integrate abiotic attributes that impact vegetation distribution, however the relationship of elevation to temperature, moisture, and solar radiation is confounded by changes in aspect, slope, and weather patterns (Perry 1995). At a given elevation, there can be significant climatic variability over time in Eastern Washington (Ferguson 2001). The relationship of elevation to vegetation is affected by the aforementioned attributes as well as landforms (Swanson 1978), soils (Daubenmire 1968), and past disturbance history (Agee 1993). Daubenmire (1968) thought that plant communities were fundamentally the products of the interaction between the environmental tolerances of the various plant taxa present and the heterogeneity of the environment.
The concept of vegetation type changing with elevation as a result of increasing precipitation and decreasing temperature is valid at a specific location. The concept has been integrated with fire (Agee 1993), insect (Amman et al. 1977), and pathogen (Beard et al. 1983) disturbance. A given elevation band can have a different temperature and moisture regime based on its location within Eastern Washington. The precipitation and temperature regime of an elevation zone in the Cascade Province is not the same north to south, nor is it the same throughout the Northern Rocky Mountain Forest Province. Forest Zones and Elevation Contour Lines The F&FR ponderosa pine, mixed conifer, and high elevation habitat types are the basis for Eastern Washington forest management prescriptions. The use of habitat types based on elevation bands results in a “vegetation zone” approach to management. Both vegetation zones and habitat types are spatially explicit land areas that support a particular set of plant associations (Lillybridge et al. 1995). The F&FR forest habitat types are based on Franklin and Dyrness’ (1973) zonal forest approach using climatic climax tree species. Forest types, “arrayed elevationally as zones are the consequence of differing responses of tree species to
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temperature and moisture gradients interacting with differing degrees of tolerance” (Franklin and Dyrness 1973:160). However, elevation bands for a specific “forest zone” move up and down slope with changes in topography, and zones often “inter-finger” with each other (Agee 1994). Adams (1994:428) provides an example of the spruce-fir forests growing in “protected valleys and ravines below the spruce-fir zone.” With the F&FR elevation zone approach, a mid-elevation contour band will capture a range of forest zones that includes forest zones typical of that contour band as well as forest zones that typically occur at both higher and lower elevations (Agee 1994).
Just as vegetation zones move up and down slope relative to topography, vegetation zones move up and down in elevation moving north or south along the Cascade Range. As an example, the grand fir series is found as low as 1,800 feet mid-way up the Northern Cascade Province (northern half of the Wenatchee National Forest), but its lower elevation limit shifts to 2,500 feet on the southern part of the Northern Cascade Province (Lillybridge et al. 1995). Thus, in the mid-portion of the Northern Cascade Province, grand fir is a part of the F&FR ponderosa pine habitat type, but in the south it is restricted to the F&FR mixed conifer habitat type. The forest series represented on the elevation gradient vary among the three ERUs (Northern Cascades, Glaciated Mountains, and Blue Mountains) in Eastern Washington.
Using the Wenatchee National Forest as an example, the F&FR dry ponderosa pine and high elevation forest habitat types fall within their designated elevation zones (0 to 2,500 feet and greater than 5,000 feet, respectively) to a much better degree than the mixed conifer habitat type (2,500 to 5,000 feet) (see Figure 2). The mixed conifer habitat type is comprised of greater portions of forest series characteristic of the ponderosa pine and high elevation forest habitat types than of the “mixed” moist forest type (see Figure 3 and Table 1). As an example, the mixed pine-fir type of Eastern Oregon and Eastern Washington, “encompasses primarily the Pseudotsuga menziesii and Abies grandis zones,” where the principal species are “both shade-intolerant (e.g., ponderosa pine, western larch, and lodgepole pine) and relatively shade-tolerant (e.g., interior Douglas-fir and grand fir)” (Tesch 1994:540).
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Figure 2. Forest Type Composition of the Forest and Fish Regulation Forest Habitat Types by Elevation Zones
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Figure 3. Vegetation by Elevation Band in the Wenatchee National Forest
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Table 1. Wenatchee National Forest Land Area and Percent of Area by Forest Series 0 – 2,500 Feet 2,500 – 5,000 Feet 5,000+ Feet Vegetation Type Area Percent Area Percent Area Percent (Acres) (%) (Acres) (%) (Acres) (%)
Deciduous Forest 451 0.26 704 0.06 48 0.01
Dry Forest/Mesic 144,866 84.78 446,987 35.37 6,530 1.11
Moist Grand Fir/Mesic Western Hemlock/ 6,125 3.58 307,947 24.37 7,940 1.35 Lodgepole Pine Wet Forest/Subalpine Fir Series/ Whitebark Pine-Subalpine Larch Associated 19,441 11.38 508,049 40.20 572,234 97.53 Species Note: Moist and wet forests approximate the F&FR mixed conifer and high elevation habitat types, respectively. Riparian Forest Series and F&FR Forest Habitat Types F&FR forest habitat types are comprised of different forest series. Forest series represented in each habitat type change within and among ecoregion provinces. With the exception of subalpine larch, the lower and upper elevation limits for riparian forest plant associations of Eastern Washington are not contained within the F&FR elevation bands and forest habitat types (see Table 2). The lower elevation limit for a riparian forest series was most often found in one F&FR elevation band and the upper limit in the next higher elevation band. Riparian forest series in Eastern Washington straddle the F&FR elevation bands and several riparian series are found in all three F&FR forest habitat types and elevation zones (see Table 3). The lack of separation of series among the elevation bands is understandable given topographic and rain shadow effects. Riparian series occur at higher elevations moving from the Wenatchee National Forest in the Northern Cascades to the Colville National Forest in the Northern Glaciated Province to the east (Kovalchik in press).
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Table 2. Forest and Fish Regulation Elevation Zones and Forest Habitat Types in Relation to Distribution Limits of Riparian Forest Series in Eastern Washington (Adapted from Kovalchik in Press) F&FR ELEVATION BANDS Ponderosa Pine Mixed Conifer Upper Elevation SERIES Habitat Type Habitat Type Habitat Type 0-2,500 feet 2,500-5,000 feet 5,000+ feet Lower Limit Upper Limit Lower Limit Upper Limit Lower Limit Upper Limit PSME (Douglas-Fir Series) Colville rare Okanogan 1,320 2,550 Wenatchee 1,320 2,550 POTR2 (Black Cottonwood Series) Colville 1,900 4,020 Okanogan 2,150 3,500 Wenatchee 1,700 3,680 THPL (Western Red Cedar Series) Colville 2,200 4,650 Okanogan 1,850 4,360 Wenatchee 1,760 4,120 PIEN (Engelmann Spruce Series) Colville 2,210 6,250 Okanogan 2,170 7,200 Wenatchee 2,380 5,920 TSHE (Western Hemlock Series) Colville np Okanogan 2,270 5,200 Wenatchee 2,080 4,720 POTR (Quaking Aspen Series) Colville 2,420 4,000 Okanogan 2,400 4,520 Wenatchee 1,980 4,210 ABGR (Grand Fir Series) Colville np np Okanogan np np Wenatchee 2,160 4,100 ABLA2 (Subalpine Fir Series) Colville 3,000 6,250 Okanogan 2,875 6,900 Wenatchee 2,550 6,620 TSME (Mountain Hemlock Series) Colville np Okanogan 5,075 5,890 Wenatchee 3,100 5,520 ABAM (Pacific Silver Fir Series) Colville np Okanogan 3,190 4,900 Wenatchee 2,380 5,520 LALY (Subalpine Larch Series) Colville np Okanogan 6,860 7,320 Wenatchee 6,860 7,320 Colville = Colville National Forest Okanogan = Okanogan National Forest Wenatchee = Wenatchee National Forest np = not present
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Table 3. Riparian Forest Series Present in Forest and Fish Regulation Designated Elevation Zones and Forest Habitat Types (Adapted from Kovalchik in Press). Ponderosa Pine Habitat Type Mixed Conifer Habitat Type High Elevation Habitat Type 0-2,500 feet 2,500-5,000 feet 5,000+ feet PSME PSME POTR2 POTR2 THPL THPL PIEN PIEN PIEN TSHE TSHE TSHE POTR POTR ABGR ABGR ABLA2 ABLA2 TSME TSME ABAM ABAM LALY
Variability Within Forest Series Added to the variability within F&FR forest habitat types across ecological regions is the heterogeneity within forest series. A forest series is defined as all the plant associations capable of supporting a given climax tree species (Daubenmire 1968, Lillybridge et al. 1995). An early seral plant community where the climax tree is a minor understory component is included with the old growth stand where the climax tree is dominant. For example, in the Wenatchee National Forest, the grand fir series most often has an overstory of Douglas-fir or ponderosa pine or both (Lillybridge et al. 1995). Grand fir may be the co- dominant species with western larch, lodgepole pine, and Engelmann spruce also present. A landscape comprised of a single forest series cannot be assumed to have a homogeneous species composition and forest structure.
Fidelity of a species to a specific forest series is rare. “Ponderosa pine is a major seral species in the Douglas-fir and grand fir series,” and is found with Oregon white oak and, on warmer, drier sites, in the western hemlock and subalpine fir series (Lillybridge et al. 1995: 38). “Douglas-fir is often the dominant or co-dominant species within stands of the Western Hemlock, Pacific Silver Fir, and Grand Fir Series”(Lillybridge et al. 1995:51).
Vegetation classification protocols for Eastern Washington forests use the climatic climax dominant tree species (Franklin and Dyrness 1973, Lillybridge et al. 1995, Kovalchik in press). Daubenmire (1968:32) suggested that “all the stands in one landscape mosaic are usually found to be components of a few successional sequences leading to still fewer climax types.” Recent use of climatic climax dominant tree species in classification work is not so much a statement about successional end points as it is a tool to group diverse plant associations. The climatic climax species serves as a mapping unit descriptor that will remain valid as current vegetation moves through development and succession stages. This use avoids the illogic use of a climatic climax approach in disturbance-driven Eastern Washington forest ecosystems (FEMAT 1993). Disturbance rarely allows forest
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development and successional processes to proceed to climatic climax in these systems. For example, Camp et al. (1996) found that approximately 12 percent of the landscape of the Swauk drainage on the east slope of the Cascades was in old growth refugia.
A polyclimax approach (Tansley 1924) recognizes that fire, edaphic, biotic, or other factors create a mosaic of different climax conditions on the landscape and may more closely represent Eastern Washington forest systems. Franklin and Dyrness (1973) describe Douglas-fir as the climax tree species in moist habitats in the Pinus ponderosa zone and as the climax species on dry ridges in the Abies grandis zone. Overlay the mosaic of different vegetation endpoints with multiple developmental-successional pathways (Keane et al. 1996) and a “naturally complex” vegetation mosaic of Eastern Washington forests emerges.
Douglas-fir is both a climax and a seral species, replacing ponderosa and lodgepole pines and western larch, but being replaced in turn on suitable sites by cedar-hemlock, spruce-fir, and grand fir. Larch would be replaced by Douglas-fir in the absence of fire, but with burning or logging disturbances that leave a bare-soil seedbed, western larch will reproduce readily and outgrow Douglas-fir. (Adams 1994). Commentary on Vegetation Classification Systems By virtue of a vegetation classification system, a diverse landscape can be categorized. But categories (e.g., forest series and vegetation zones) are relatively general. The plant associations within each forest series allow greater resolution of current forest conditions, future stand development and successional stages, productivity, and response to management (Lillybridge et al. 1995). However, plant associations are climax abstractions and not continuous map themes of what is actually on the ground. A potentially more appropriate tool is a natural vegetation map currently under development for the forests of Washington (J. Hemstrom personal communication). This map will incorporate information on the climatic envelope of the major forest tree species and the disturbance regimes that affect stand development and successional stages. Perhaps, with GIS technology and improved information on vegetation plant associations (Williams and Lillybridge 1983, Johnson and Clausnitzer 1991, Lillybridge et al. 1995, Kovalchik in press) and disturbance regimes, it may be possible to describe “prevailing climax” conditions for Eastern Washington forests (Whittaker 1960 in Agee 1993). With continuous map themes of current forest conditions and knowledge of the stand development and succession pathways of their respective forest series and plant associations, realistic resource goals and management practices may be derived. The information needed to achieve the stated goal of the Eastern Washington riparian prescription package, “to promote dynamic forest stand conditions that vary over time as would emulate the result of natural disturbance regimes,” may soon be available.
In summary, the literature indicates forest vegetation zones are comprised of a mix of different forest series. This is especially true for the mixed conifer habitat type in the 2,500 to 5,000 feet elevation zone. Forest management practices based on elevation zones and the three forest habitat types (ponderosa pine, mixed conifer, and high elevation forests) may lack the resolution needed to lead to sustainable forest systems.
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Historical Reference Conditions
“A science of land health needs, first of all, a base datum of normality, a picture of how healthy land maintains itself as a organism.”
Aldo Leopold, 1941 (In Swetnam et al. 1999)
Current forest conditions are not suitable as a reference for sustainable forest management because of significant changes in disturbance regimes and forest structure and composition that have created forests with significant “health” problems (Sampson et al. 1994, Covington et al. 1994). Opinions differ as to the relative threat of changes in inland forests this century, but there is general agreement that changes have occurred (Baker 1988, Brown 1983). In dry forests, Douglas-fir and “closed” pine stands have generally taken the place of more “open” ponderosa pine stands. In moist forests, the shift has generally been toward grand fir-western hemlock-western red cedar stands and away from western white pine-western larch stands (Harvey et al. 1994, Mutch et al. 1993).
Shifts toward late-successional species occurred relatively rapidly, compressing successional processes. The successional process for Douglas-fir in the dry forest of Southern Idaho normally requires 300-400 years with historically frequent fire regimes. Data indicate that this successional process has been compressed into only 40 years as a result of fire suppression (Harvey et al. 1994). Similarly compressed successional processes have been observed in the Coeur d'Alene Mountains in Northern Idaho where western white pine- dominated ecosystems have been succeeded by late seral species in less than 50 years, rather than the 200 to 300 years expected under historic disturbance regimes (Moeur 1992 in Graham et al. 1995). Characterizing Natural Ecosystem Variability Dramatic changes in Eastern Washington and Oregon forests caused significant concern to the public and led to the demand for a science-based approach to forest management practices (Everett et al. 1994). This landscape ecology approach to ecosystem management (Jensen et al. 1996) depends heavily upon Hunters’ (1991) coarse filter approach to conserving biodiversity and resource productivity. Under the coarse filter approach, known and unknown biodiversity components are conserved by maintaining historical disturbance effects and resulting patch dynamics.
The concept of historical range of variability [HRV] in ecosystem structure or process is valuable in understanding and illustrating the dynamic nature of ecosystems; the processes that sustain and change ecosystems, especially disturbances; and the current state of the system in relationship to the past. (Morgan et al. 1994:105)
Swetnam et al. (1999) considered the use of historical context as a tool for evaluating forest conditions to be especially important because of concerns related to human-caused environmental changes.
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Historical reference points, and specifically, HRV, have become a common standard to evaluate current resource conditions and disturbance regimes (Caraher et al. 1992, Swanson et al. 1994, Lehmkuhl et al 1993, Hessburg et al. 1999). Morgan et al. (1994:101-102) suggested that HRV provides an indication of the “range of desired future conditions,” and “acceptable bounds for ecosystem change.” Swanson et al. (1994) used HRV of both natural states and disturbance regimes to characterize natural ecosystem variability. Limitations of HRV Many of the seventeen questions posed by CMER SAGE seek information on historical conditions and disturbance regimes. The text above adds credence to those requests. However, there are potential negative aspects to the HRV approach. A major limitation on the use of HRV has been determining the timeframe to use in establishing the historical period. Timeframes of 100 to 400 years before present (BP) have been suggested (Hann et al. 1993, Steele 1994). Often the limiting factor is a diminishing record back in time. Successfully describing HRV is also dependent upon selecting the appropriate spatial scale to capture the dynamics of the condition or process (Morgan et al. 1994). Too fine a scale and the noise level hides information. Too large a scale and information is lost in the summation process.
Although very defensible historical data for fire (Agee 1993) and insect disturbances (Swetnam et al. 1995) on a stand or forest type basis is available, there is a lack of continuous map themes over large areas. Both the Eastside Forest Health Assessment and the larger Columbia River Basin Assessment utilized sub-sampling (less than 15 percent of the assessment area) to derive estimates of historical change (Lehmkuhl et al. 1994, Hessburg et al. 1999). Therefore, estimated historical disturbance and resulting vegetation change must be extrapolated for a majority of the landscape.
These recent assessments have relied on historical aerial photographs to define historical conditions and disturbance regimes. Unfortunately, the limited time span from when aerial photographs became available in the late 1930s to the present may lead to an underestimation of the real changes since European settlement (Lehmkuhl et al. 1993). This concern was substantiated in stand reconstruction of Eastern Washington forests that showed significant changes in species composition and tree density between European settlement (1860) and the 1940s (Everett et al. 1997, Everett et al. 2000).
However, the above concerns are minor compared with other potential problems in the use of HRV, such as:
• The assumption that historical conditions were sustainable may not be valid. • Historical fire effects (regimes) may not be re-established because of the absence of indigenous burning and current societal constraints. • Future global climate change may no longer support historical forest composition structure and inherent disturbance regimes. • HRV may be too restrictive under an expanding human population.
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Implicit in the use of historical reference points is the assumption that historical conditions prior to European settlement were sustainable (i.e., they conserved biodiversity and site nutrient capital). This assumption has yet to be tested. As an example, the disturbance return interval:recovery period ratio needs to be 1 for a sustainable system to exist (Turner et al. 1993). In other words, a system must have time to reach its pre-disturbance state before the next disturbance or site degradation can occur. Too extensive a period without disturbance allows a buildup of biomass and more severe disturbance events are possible. When the established fire frequency interval (FFI, or disturbance return interval) was graphed against the current fire free period (FFP, or recovery period) for mixed conifer forests in Eastern Washington, the ratio was rarely equal to 1 for the period from 1796 to 1916 (Everett et al. in press). Eastern Washington forest sites showed cycles of both too frequent (FFP < FFI) and too infrequent burning (FFP > FFI) to have “sustainability,” and the patch mosaic was not in a dynamic steady-state.
Indigenous burning played a significant role in defining the forest composition and structure of dry Douglas-fir and ponderosa pine forest east of the Cascades (Barrett and Arno 1982, Agee 1993). If HRV conditions are derived from indigenous burning, it may not be possible to re-establish pre-European settlement forests.
Historical conditions or disturbances were the part of the larger disturbance potential that was realized. Other historical scenarios were possible given the ignition sources, fuels, insects, pathogens, and storm events. These unrealized scenarios of disturbance and vegetation condition may be more conservative of biodiversity or site nutrient capital, but did not occur because of chance. Limiting forest conditions to historical ranges may not provide the required flexibility to meet future public demands for resource conditions and disturbance regimes.
Historical and current disturbance regimes and forest conditions may be irrelevant, given the projected changes in global climate on Eastern Washington. “Over the next century, radical changes in climate are expected to have a marked and lasting impact on forests of the Inland West” (Covington et al. 1994:44). Climate change is predicted to affect future forest conditions by altering forest processes, disturbance regimes, and biodiversity (Dale et al. 2000). The mean seasonal severity rating (SSR) is estimated to increase by 10 to 30 percent by 2060 for Eastern Washington using the Canadian general circulation model (GCM) and Hadley GCM fire models (Dale et al. 2001). SSR is a measure of fire weather severity and potential area burned. Elevated carbon dioxide and climate changes could significantly alter insect and pathogen disturbances (Ayres and Lombardero 2000).
In summary, historical reference conditions provide valuable tools in the development of knowledge for evaluating sustainability of forest systems. They can be used to estimate how far out of phase current disturbance regimes have become and the resultant changes in forest vegetation composition and structure. However, historical conditions may not have been sustainable, and climatic change may make historical conditions irrelevant. In the future, the knowledge base, rather than the historical condition, will be needed to develop resource objectives and to develop forest management practices.
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Section 4.0 Questions
Question 1
For each type of disturbance, what is the current and what were the historical (e.g., 200 years ago) frequency, magnitude (e.g., size of disturbance patches in forest and whether single tree, small gap, or large gap), and intensity (e.g., heat and duration of fire) of disturbance? Currently and historically, is there a difference in the periodicity, magnitude, and intensity of fire in upland and riparian areas? Response Current and Historical Disturbance Characteristics There is a very large information base on historical and current disturbance regimes within Eastern Washington forests. Information is available on the inherent fire, insect, and pathogen disturbance regimes for every forest series present. The differences between current and historical disturbance regimes for fire are better defined than for insects and pathogens because of the permanent fire scar record.
Characterizing disturbance effects on forest types is a complex undertaking that is difficult to summarize according to broad forest categories or general disturbance types (e.g., Kovalchik’s eight forest series types or F&FR elevation bands). The interaction of several disturbance types or re-occurrences of the same disturbance types requires understanding of the synergistic effects of disturbances, or the development of “composite” disturbance regimes (currently underway). Use of such broad forest classifications masks other characteristics that play a significant role in the severity, extent, and frequency of disturbances, such as the presence and type of understory shrubs and stage of stand succession. Alteration in Disturbance Regimes Prior to the arrival of indigenous peoples to Eastern Washington, the disturbance regimes of the forest were defined by the vegetation composition and structure, landform, soils, climate, and the disturbance agents (fire, insects, pathogens, and severe weather). This “inherent” disturbance regime (Everett et al. 2000) was altered by the burning activities of the indigenous people. Indigenous peoples increased fire frequency, and may have reduced insect and pathogen effects in the process. With the removal of the indigenous peoples burning effects from around 1890 (M. Ubelecker personal communication), Eastern
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Washington forests were on a trajectory back to the “inherent” disturbance regimes. However, this transition was truncated by fire suppression activity initiated around 1910. Summary Information By Disturbance Type Fire
• The natural patterns of fire frequency, extent, and distribution in Eastern Washington were significantly altered beginning in the early 1900s, when land managers began fire suppression practices. • In general, fire frequency decreases along the ecological gradient from warm/dry ponderosa pines to cool/moist subalpine firs. • Fire severity is usually inversely related to fire frequency (Perry 1995). • Both fire spread and severity are linked to the amounts and moisture content of fine surface fuels, fuel ladders to the crown, height to the base of the crown, crown cover, and crown density (Agee 1993). • Kovalchik’s (in press) description of fire history for Eastern Washington forest plant associations suggests that, historically, those plant associations in moist environments avoided or had less severe fire events than more xeric plant associations within the same forest series. Whether this phenomenon can be extrapolated to differences between adjacent riparian and upslope plant associations remains undetermined. • In more xeric upland forests, there are increased fire hazards to the riparian plant associations (Kovalchik in press). • Riparian forests have somewhat longer fire free intervals than upslope forests regardless of slope aspect (Everett et al. in press). • Traditionally “umbrella” type fire regime descriptions – where general descriptors of fire severity, frequency, and extent are assigned to each forest series – are used (see Table 4). However, this approach masks significant variability in fire regime among plant associations within the forest series.
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Table 4. Fire Regimes for Eastside Forest Series (Adapted from Agee 1993; Agee 1994; Everett et al. 2000; Schellhaas et al. 2000) FOREST SERIES FIRE SEVERITY FIRE FREQUENCY FIRE EXTENT Ponderosa Pine Low with small patch Frequent Large underburn, replacement (3- 40 years) clumped pattern (less than 1 hectare per patch) Douglas-Fir Low in warm/dry areas Frequent in warm/dry Large underburn, White Fir increasing to moderate in areas with reduced clumped pattern with Grand Fir cool/moist areas frequency in cool/moist large stand replacement areas fires (500-1,000 hectares) Lodgepole Pine Moderate, includes low Moderate From individual log to severity “cigarette burns” to (40-80 years) corridors high severity stand (less than 30 meters to replacement events 1/3 of stand) Western Hemlock Low to moderately high Moderate Large, topographic Western Red Cedar (50-100 years) barriers define burn size Long (10,000 to 20,000 (150-500 years) hectares) Subalpine Fir High Long Small fires (146 Mountain Hemlock (more than 100 years) hectares) dominate over large fires
Insects and pathogens
• There is a significant gap in knowledge about historical insect and pathogen disturbance regimes in Eastern Washington forest types. A notable exception is the history of spruce budworm outbreaks in the Blue Mountains as interpreted from tree ring analyses (Swetnam et al. 1995). What little information is available indicates that insect and pathogen outbreaks have become more frequent, of longer duration, and more severe in recent times. • The current insect and pathogen disturbance regimes have been well summarized as part of the Eastside Forest Health Assessment, the Columbia River Basin Assessment, and other work (e.g., Lillybridge et al. 1995). • Vulnerability of forest series to insect and pathogen hazard varies among and within ERUs depending upon past management actions. • The threat of defoliation to subalpine fir, Pacific silver fir, western hemlock, western red cedar, and mountain hemlock has increased through larger and more contiguous bands of host communities (Hessburg et al. 1994). • Conditions for optimal spread of root diseases and dwarf mistletoes exists in many parts of the lodgepole pine, ponderosa pine, Douglas-fir, and grand fir climax series (Hessburg et al. 1994). • Some general trends by forest series type are evident:
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♦ There are relatively few serious insect or pathogen pests in the subalpine forest series.
♦ In the western hemlock and western red cedar forest series, insect pests remain few, but pathogen effects have significantly increased.
♦ In the lodgepole pine forest series, mountain pine beetle and dwarf mistletoe increase fire hazard.
♦ In the Douglas-fir and grand fir forest series, pathogen impacts have declined, but insect effects are not potentially serious.
♦ In the ponderosa pine forest series, insects remain serious pests.
Other disturbance types • A review of the literature revealed no information on the current and historical patterns of other disturbance types (e.g., ice storms and debris torrents). Differences Between Riparian and Upland Areas Sufficient information is available on vegetation response to disturbance at the individual tree, stand, and landscape level to predict, with some confidence, forest response to applied disturbances. Predicting vegetation response is dependent upon the knowledge of the disturbance magnitude and the development stage of the PAG or forest series. However, information on differences in riparian and upslope forest disturbance regimes and post- disturbance response is not well known.
Fire suppression techniques have reduced the periodicity of fire in both upland and riparian forest types. Current attempts to buffer forest systems from fire, insect, and pathogen disturbances have resulted in forest structure and composition that no longer reflects the inherent disturbance regime. As a result, when fires do occur today, they are large in extent and can be stand-replacement events.
Disturbance relationships between upslope and riparian forest fire regimes are being defined. There does not appear to be a consensus as to whether there is a distinct difference between fire effects in riparian versus upslope areas. Fire severity, extent, and patterns are functions of more than just forest type – moisture levels, aspect, slope, season, understory shrubs, valley type, and adjacent community types – all have been shown to play a role. There is an information gap in insect and pathogen relationships at this ecotone.
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Question 2
Does elevation correlate with historical fire frequency? If so, how? Did this differ between upland and ecological riparian communities? Are there other parameters that were used in the scientific studies to define areas of differing historical disturbance patterns and historical stand conditions? Response Correlation of Elevation with Historical Fire Frequency Elevation is related both directly and indirectly to fire frequency (as well as extent and severity) in several ways. Lightning strikes are more common on the upper one-third of slopes, which increases the probability of fire ignition at higher elevation. Landform influences the spread of fire by channeling winds and the potential for producing a chimney effect that increases fire spread and intensity (Agee 1988). Elevation affects the climate and species composition of a site, thereby indirectly influencing fire behavior (Williamson 1999).
The literature suggests that these topographic influences on fire effects do vary between riparian and upland communities. In general, riparian vegetation is often assumed to burn less frequently than upland vegetation (Hinselman 1973, Romme and Knight 1981, Agee 1994) and in some cases these systems form a firebreak. The increased amount of available moisture reduces the chance of carrying a low-severity fire.
However, under certain weather conditions, the complex, multi-layered structure of riparian systems, combined with fire-sensitive species, can make such systems particularly susceptible to intense fires (Williamson 1999). Under these circumstances, the riparian system could burn with greater intensity than surrounding uplands (Agee, 1994, Agee 1998, Williamson 1999) and produce a higher crown fire hazard than surrounding uplands.
With increasing elevation, riparian systems exhibit less frequent but more severe fires than similar lower elevation areas. In lower elevation, dry riparian systems, the presence of charred live trees, charred stubs, and rings of charred tissue around the base of live trees suggest the occurrence of low-severity fires in the past (Agee 1998). Riparian trees with fire scar are common (Heyerdahl and Agee 1996). At higher elevations, riparian areas perhaps burn less frequently, but occasionally more intensely (Agee 1994). Agee (1998) applies a 250-1,000 year return interval for fire in “hydric” or riparian forests in mid- and high- elevation zones.
When fires do burn riparian areas, the effects can be more severe than in associated upland areas. Crowe and Clausnitzer (1997) found that riparian areas extend what are generally higher elevation plant series into lower elevation drainages. Riparian areas act as conduits for water and cold air drainages at night. Higher moisture inputs and lower evaporation produce a riparian forest that is cooler, moister, and more complex than associated uplands (Brosofske et al. 1997, Naiman et al. 1998, Williamson 1999, Olson 2000). Species with higher moisture requirements generally have a lower resistance to fire. This lower resistance,
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combined with vegetational complexity, results in severe fire effects and increased mortality. Additional information concerning the historical fire patterns and the linkages between elevation and fire disturbance is available from the Wenatchee National Forest. Influence of Other Parameters on Disturbance Patterns and Stand Conditions Many studies stress that the elevation-fire relationship is not the sole determinant of fire frequency and severity. In many cases, related variables such as slope, aspect, and forest stand composition play equally important roles. For example, Heyerdahl (1997) and then Olson (2000) found that fire frequency in the Blue Mountains did not vary due to aspect or elevation. The exceptions were cases where the terrain became more dissected as elevation increased, in which case fire return intervals increased. With increased elevation, forest composition changes in response to topography and temperature. Agee (1994) stated that because changes in vegetation correspond with changes in elevation, the plant series is useful to describe the fuel profile. However, Agee, in the same manner as Kovalchik, felt that “the location and extent of a plant series [and therefore the use of elevation] often required local interpretation” (Agee 1994:6).
The relationship between elevation and forest stand type appears to play a particularly important role in insect and pathogen disturbances and how such disturbances ultimately affect the landscape. For example, in situations where trees are defoliated by western spruce budworm, there is a change in host tree disposition associated with elevational gradients, a synchronization of bud burst with larval emergence from hibernation at higher elevations supporting shorter growing seasons, and reduced budworm survival at high elevations (Stoszek 1988). At high elevations, a dynamic tension exists between Douglas-fir/true firs and ponderosa pine (McCullough et al. 1998). With historical- and regular-interval fire, sites were likely occupied by ponderosa pine. After fire control was initiated, seral pine stands shifted to late-successional stands of shade-tolerant Douglas-fir and true firs, the favored host of tussock moth (Wickman 1978, Wickman 1990).
The density of forest types also plays a role in disturbance magnitude and stand condition. Current, late-successional forests with higher densities (as a result of fire suppression) in Eastern Oregon and Washington have the same insect and pathogen compliment as the traditional old forests, but the increased continuity of hosts across the landscape leads to an intensification of the magnitude, severity, and duration of outbreaks (Everett et al. 1994, Hessburg et al. 1993).
Elevation, climate, geology, and vegetation condition are key determinants of disturbance. Swanson (1981) found that the magnitude and scale of fire effects are, in addition to the size and severity of the fire, related to the geology, topography, and stream system size, as well as the amount, magnitude, and timing of post-fire precipitation events in the area. For example, landslides are produced from overloading already unstable slopes with additional sources of water from intense precipitation events, interception and redirection of groundwater flow paths due to roads, forest cutting that reduces rooting strength, and increased soil water volumes from decreased evapotranspiration. These slides can be delivered to the heads or sideslopes of incipient drainages to produce a disturbance cascade (Miles et al. 1984, RIPARIAN DISTURBANCE REGIMES IN EASTERN WASHINGTON Concurrent Technologies Corporation - 28 -
Nakamura et al. 2000). Debris slide initiation is more likely to have higher severity of disturbance in the upper elevation zones, but affect a small percentage of lower order/lower elevation channels in any one storm (Swanson et al. 1998).
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Question 3
What was the persistence and resilience of various stand types to disturbance? What was the typical pattern of recovery in terms of time and species composition following disturbance? Are some communities dependent upon fire to promote reproduction or other ecological processes? Do the answers to these questions differ between ecological riparian communities and upland areas? What are the expected future stand succession and disturbance patterns in the presence of fire suppression? Does this vary by stand type or other parameters? Response Persistence and Resilience of Various Stand Types Persistence, or the more widely used term “resistance,” refers to the ability of a forest stand to withstand disturbance without significant structural change (i.e., changes beyond the natural range of variation). Resilience describes the extent to which, following disturbance, a forest stand becomes re-established in its pre-disturbance condition (Agee 1993, Obedzinski et al. 2001). For example, low growing and flexible woody species found in riparian avalanche zones are capable of withstanding the force of sliding snow (thereby demonstrating resistance). These plant communities survive avalanche by rapid growth habits and vegetative reproduction (thereby demonstrating resilience) (Cushman 1981, Naiman et al. 1992).
Individual tree species have quite different resistance and resilience characteristics that have been summarized by Starker (1934), Agee (1994), Hessburg et al. (1994), Lillybridge et al. (1995), and Kovalchik (in press). Forest stands will demonstrate the summation of the resistant and resilient attributes of individual tree species, as influenced by stand development stage. For example, a forest stand with flammable foliage (e.g., subalpine fir) will be less resistant to fire disturbance when it has a well-developed crown versus an earlier, more open, developmental stage. White (1987) defined a feedback loop between the successional stage of the plant community and its susceptibility to disturbance as a specific period that varies with forest series (U.S. Department of Agriculture Forest Service 1992).
Based upon review of several studies (Miller and Kean 1960, Arno and Davis 1980, Cooper and Pfister 1984, Peterson and Ryan 1986, Mitchel 1987, Stoszek 1988, Biswell 1989, Oliver and Larson 1990, Camp et al. 1996, Payne et al. 1996, Graham et al. 1999), it appears that, in general, heterogeneous landscapes with discontinuous fuels, a range of insect and pathogen hosts, and a mix of successional stages are most resistant to disturbance effects. High stand resilience seems closely tied to high levels of biological diversity and nutrient availability (Brown and DeByle 1989, Meffe and Carrol 1997). However, much of the current information about forest stand persistence and resilience comes from post-fire suppression studies. There appears to be little quantitative data about historical responses of entire stand types to disturbance.
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Typical Pattern of Recovery Little is known about historical successional pathways following disturbance. However, current studies indicate that potential successional development pathways following forest stand disturbance are highly site and disturbance-specific (Arno et al. 1985, Everett et al. 2000). Approaches that seek to incorporate site-specific vegetation, climate, and disturbance parameters (e.g., Columbia River Basin Succession Model – CRBSUM – by Keane et al. [1996] and the Ecosystem Diversity Matrix by Haufler [1996]) may more accurately predict future forest conditions than any single historical model. Fire-Dependent Communities The standard example of a fire dependent forest type is lodgepole pine and its serotinous cones that disperse seed following a crown fire event (Wheeler and Critchfield 1985, Kauffman 1988). Aspen stands are another example. They need fire to renew clones and protect young trees from encroachment by firs (Bartos et al. 1983, Brown and DeByle 1989). Ponderosa pine stands are also dependent upon fire to reduce the understory of shade tolerant Douglas-fir and true firs (Mutch 1970). These examples illustrate the general principle that all forest series (and, by extension, their surrounding communities) are dependent upon some sort of disturbance to maintain diversity of stand conditions. Heterogeneous landscapes break up continuity in insect and pathogen hosts and fuels (Lehmkuhl et al. 1994, Hessburg et al. 1994) and thus reduce the probability for catastrophic disturbance events (Everett et al. 1996). Insects, pathogens, and fire all play roles in nutrient cycling, habitat creation, and normal successional processes (Haack and Byler 1993, Hessburg and Everett 1993). Riparian Versus Upland Communities Current studies (Morse 1999, Everett et al. in press) indicate that burn severity is much less in moist riparian areas versus upslope forest areas in Eastern Washington. However, current research is based on forest conditions with significant increases in upslope forest cover. It is unknown whether, under more natural fire regimes with reduced upslope forest densities, this was a trend in historical times as well.
Obedzinski et al. (2001) present a simple model of resistance and resiliency for riparian systems in which systems that resist disturbance or are highly resilient continue on their projected development. Systems where disturbance exceeds recovery potential enter a degradation cycle. Another theory suggests that because riparian and upslope forests share a majority of the same plant associations (Kovalchik in press) more similarities than differences in individual and stand resistance and resilience could be anticipated.
The CTC project team’s search revealed no available information on the differences between resistance and resilience to insect disturbances between riparian and upslope forest. Expected Future Succession Patterns All biomass is cycled. If it is not cycled by fire, then it will be increasingly cycled by insects and pathogens (Hessburg and Everett 1993). With increases in fire suppression in recent RIPARIAN DISTURBANCE REGIMES IN EASTERN WASHINGTON Concurrent Technologies Corporation - 31 -
years, an increased duration of insect outbreaks has already been observed (Flanagan personal communication). Stand succession without fire will move forests toward climatic climax and catastrophic fire disturbance events when they occur (Ottmar and Sandberg 2001, Everett et al. 1996).
With regular fires, shade-intolerant early or mid-seral species historically dominated the landscape (Mutch 1970). Without fire, shade tolerant late seral to climatic climax species will continue to have the competitive edge (Kauffman 1988). Forest series with the longest fire return intervals, such as western hemlock or subalpine fir (greater than 300 years, Covington et al. 1996), may be the least affected internally by continued fire suppression.
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Question 4
What portion of the landscape was likely to be affected by disturbance historically? How does that differ from the current situation? Response Fires Both historically and currently, there is limited regional-scale information on what portions of the landscape are most affected by fire disturbance. The spatial scale of studies assessing effects of fire has been restricted to point observations and stream transects. Attempts to generalize effects to aquatic systems at the landscape or regional scale have been rare (Gresswell 1999).
Historically The geographic extent of historical fires is not well known. Cross-dating of fire scars has been used to some extent to address this issue, largely to develop maps of fire distribution in ecosystems where low-intensity fires were frequent (Agee 1994). Areas that experienced high-intensity burns would have distributions that are observable for a century or more from the mosaic pattern of different-aged stands. Much of the Cascades burned over in a massive forest fire during the 14th century, and many smaller fires have burned since then (Perry 1988).
Historical environments were diverse and constantly changed, which produced frequent stress in vegetation. The typical temperature and moisture patterns of the inland Northwest – wet, cold winters and warm, dry summers – were at times severely limiting to biological decomposition and produced conditions which promoted wildfire. Biological decomposition was therefore constrained, but frequent wildfires maintained nutrient cycling via burning (Olsen 1981). Fire-resistant species dominated the sites that often burned, and most native pests were stress sensitive (Stoszek 1988).
Current Situation Currently, fires are often extinguished quickly, with the result that forests burn less frequently (Baker 1992). Fires that do burn are more severe, because of accumulated fuels, and result in loss of vegetation and organic matter storage (Harvey et al. 1993). Fire-adapted species are reduced and non-fire-adapted species are increasing where they were historically excluded by frequent fire (Harvey 1994). At the landscape level, there has been a shift in fire regime (Pickett et al. 1989). This shift is sufficient to alter the stability of forest ecosystems.
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Pests and Disease Historically In the interior forests east of the Cascades, periodic insect outbreaks appear to be a part of the normal historic pattern (Perry 1988). When a disease, parasite, or herbivore attacked a forest stand, the pattern of damage was often irregular and patchy in distribution. There is evidence that this distribution was often the result of a combination of localized distribution of the attacking species and the apparent preference or avoidance of certain tree phenotypes (Linhart 1988).
In the Blue Mountains, large expanses of open ponderosa pine forests were likely regulated by bark beetles in old-age forests, or fire in immature forests. This resulted in a patchwork of age classes (Wickman et al. 1994). Based on historic descriptions and inventory records, the stands were mostly old age, open grown, and dominated by pine. Remaining old-growth mixed-conifer forests at higher elevation and more mesic sites left tree-ring histories that showed about seven to ten budworm or tussock moth outbreaks over the last two centuries (Wickman et al. 1994). According to tree-ring analyses, these outbreaks apparently caused heavy defoliation and were often synchronous across the Blue Mountains.
Current Situation Several characteristics of the landscape have changed over the last century. More uniformity in species distribution allows pests to multiply and disperse much more effectively across a landscape. Defoliating insects and bark beetles (e.g., western spruce budworm and tussock moth) are the most serious pests of interior forests. Wind currents disperse the larvae of these outbreak defoliators. Their survival and the rate of spread depend on the distribution of host and non-host plant species across the landscape. Landscape patterns also influence the habitat for birds, mammals, and spiders that prey on defoliators and bark beetles. Logging roads and increased traffic have facilitated the spread of at least five pest species (gypsy moth, cedar root rot, black stain root disease, tansy ragwort, and spotted knapweed) in the Pacific Northwest.
In white and sugar pine country, the introduction of white pine blister rust early in the 20th century is reducing these species in many areas to less than half of what they were just 40 years ago (Monnig and Byler 1992, O’Laughlin 1994). Ponderosa pine, western larch, and white and sugar pine are broadly adapted and relatively tolerant of many native diseases and insects, but populations have been strongly reduced in the absence of fire. Other native conifers are narrowly adapted and poorly tolerant of changes in their environment or with associated native insects and diseases (Harvey 1994).
The current forests of the Blue Mountains have been so altered that shade tolerant fir now grows on many pine sites historically maintained in a seral state by fire. These stands are 90 to 140 years old and appear to be regulated by forest insects (budworm and tussock moth) and diseases (Wickman 1994). Tussock moth studies over a 20-year period showed a pattern of recurring increases and declines caused by density-dependent factors. The latest budworm outbreak in the Blue Mountains has killed most of the host trees in both fir-invaded pine and historically mixed-conifer. The level of insect populations and resulting host damage
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indicated in 1994 was considered highly unstable and likely new to the ecological history of the Blue Mountains (Wickman 1994). Fire-Insect Relationships Historically Historically, both low intensity defoliator outbreaks and surface fires probably kept fuel accumulations low and prevented and/or delayed catastrophic stand replacing fires or insect outbreaks. It is unlikely that tree mortality rates similar to the 80 percent recorded in a recent budworm outbreak could have been sustained historically (Swetnam et al. 1995).
Current Situation Although major disturbances such as fire or insect outbreaks appear to be independent events, causality exists (McCullough et al. 1998). The spatial and temporal patterns that result from disturbance often reflect a synergism among disturbance agents acting within the physical limits of the landscape and ecological processes (Hadley 1994). One disruption to an ecosystem often sets the stage for others (e.g., if the potential exists for windthrow due to a clearcut edge, downed trees from the windthrow may provide a large food base for some species of bark beetles).
Episodic outbreaks of the major defoliators have served a complementary role to that of surface fire by directing succession (Wickman 1978). For example, budworm and tussock moth fed on late-successional Douglas-fir and true firs, but left seral pines.
Fire also alters the abundance and spatial-temporal continuity of preferred host species and nutrient cycling and availability, which in turn, determines the quality of trees as hosts (Attiwell 1994). In pine forest of the interior Northwest, extensive, even-aged stands of lodgepole pine, usually established by fire, can promote bark beetle outbreaks. This is a self- maintaining pattern – beetle infestations create large amounts of fuel thereby increasing the potential for wildfire, and fire, in turn, initiates development of new even-aged lodgepole pine stands (Amman and Schmitz 1989, Stuart et al. 1989). When no fire occurs after outbreak, lodgepole may be replaced by ponderosa pine at low elevations or by Douglas-fir at higher elevations (Mitchell 1990). Fire can predispose surviving trees to attack by insects by scorching or wounding, particularly phloem-boring bark beetle and/or wood borers (McCullough 1998).
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Landslides and Debris Torrents Historically In areas with steep slopes, landslides were the dominant erosional mechanism (Robison et al. 1999). Ketcheson and Froelich (1978) and Ice (1985) found that even in areas with high landslide densities, landslides directly affected less than 2 percent of the land surface. Impacts of landslides on small streams (1st to 3rd order) can be severe and extensive (Swanson et al. 1981b, Robison et al. 1999). While landslide features may constitute less than 1 percent of the total land surface in Pacific Northwest mountainous terrain, they can scour and affect over 10 percent of the channel network (Swanson et al. 1987).
Current Situation It has been postulated that present-day increases in logging and road building have contributed to increased landslide frequency and severity. However, several studies that have examined differences in landslide patterns between relatively pristine or mature forests and more intensively managed sites have shown only mixed support for this theory. A variety of factors including precipitation patterns, slope, soil type, management, and forest type all play a role. In some cases, the complexity of the interactions makes it difficult to discern management-related effects from natural variability (Ice 1985, Sidle et al. 1985, Meehan et al. 1991, Robison et al. 1999).
Robison et al. (1999) found landslide density to vary from 0.4 to 24.4 landslides per square mile out of 45.8 square miles where landslides entered stream channels. The majority of the landslides were not associated with roads. The highest risk for shallow rapid landslide was found on slopes over 70 to 80 percent, depending on landform and geology. A moderate landslide risk existed on slopes between 50 to 70 percent. Landslides that entered stream channels during the storms of 1996 occurred in very steep landscapes or adjacent to stream channels. At least 78 percent of the upslope (versus channel initiation site) landslides occurred on high risk sites (i.e., “red zones” with steep slopes and the potential for water accumulation). Earlier studies have speculated that the greatest increase in landslides occurred after roots had decayed and before new roots could take hold, typically a few years after timber harvest.
Swanson et al. (1987) found that erosion rates were 1.2 to 1.3 times greater (up to four times greater on the most landslide-prone sites) than unmanaged mature forests for most landscape types in 1,300 acres on the Mapleton Ranger District of the Siuslaw National Forest in Oregon. This study compared an aerial photograph-based clearcut sample to a ground-based forest sample, likely underestimating erosion rate ratios. However, Martin (1997) found no significant differences in landslide occurrence between mature forests, clearcuts, and leave areas.
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Robison et al. (1999) found no significant differences in landslide density and erosion for their four “red zone” study areas between four age classes (0 to 9 years – recent clearcut/very young forest, 10 to 30 years – young forest, 31 to 100 years – forest, and older than 100 years – mature forest). The lack of differences, Robison explained, was in part due to great differences in landslide characteristics between the study areas. In three out of four study areas in very steep terrain, however, both landslide density and erosion volumes were greater in the 0 to 9 years-age class. Stands within the age classes spanning 10-100 years had lower incidences of landslide than the mature forest.
Forest practices may alter both physical and biological (vegetation) properties related to slope stability. Physical changes that can occur include slope steepening, the addition of soil moisture, and alterations in shear strength. Some of the most important slope stability changes are caused by haul roads and skid trails (Sidle et al. 1985). Almost all major road- related landslides that delivered sediment to streams investigated by the Oregon Department of Forestry (ODF) prior to the 1996 storms were related to road fills or road sidecast (Mills 1991). Toth (1991) found that roads in Washington that were constructed in the last 15 years survived a landslide-inducing storm with minimal damage, while roads constructed earlier had very high damage rates. ODF found that road drainage caused about one-third of the investigated landslides (Mills 1991). Culverts were associated with 29 percent of damaged sites in the Deschutes River Watershed in Washington (Toth 1991).
Most landslide studies are based on aerial photograph interpretation, a technique that has come under some criticism (Pyles and Froehlich 1987) for its inability to detect landslides due to photograph angles and the obscuring effect of tall trees. Prior to the study by Robison et al. (1999), a systematic ground-based sample of landslide occurrence was conducted in only two other forest landslide studies. Hughes and Edwards (1978) investigated a study area of about 0.3 square miles. Ketcheson and Froelich (1978) field-investigated 100-acre or smaller watersheds in the Mapleton, Oregon area that were not influenced by forest roads. The inability to accurately determine the proportion of the landscape that is or was likely to be affected by disturbance, without field verification, leaves a critical data gap.
A variety of geomorphological processes may be linked sequentially, producing what Nakamura et al. (2000) termed “disturbance cascades.” These cascades can propagate down gravitational flowpaths from hillslopes through stream networks, particularly through geologically unstable mountainous areas like the Pacific Northwest. In steep terrain, small shallow landslides often transform into debris flows – a semi-fluid, viscous mass scouring soils from slopes along its path. Once the debris flow enters a channel network it becomes a debris torrent. In some cases, a landslide that begins with 10 cubic yards of material or less may become a debris torrent, moving thousands of yards of material and depositing it where the channel gradient declines (Benda and Cundy 1990). On larger streams (4th or 5th order), debris torrents may be immediately entrained in rafts that become jams at a confluence with larger channels. Congested log transport from debris torrents has been known to remove large riparian trees (e.g., 30-year-old alders in recent floods in the Pacific Northwest) (Swanson et al. 1998, Wondzell and Swanson 1999). Larger channels will have a more dispersed disturbance with areas of removed, toppled, and standing trees. Thus, there is a
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gradient of decreased overall disturbance severity and increased variability in severity as the cascade is propagated downstream (Nakamura et al. 2000).
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Question 5
How did historical disturbance patterns affect vegetation condition by stand type? Historically, what portion of the upland and ecological riparian forests (by stand type) were likely in a climax and early successional conditions? Response Effect of Historical Disturbance Patterns Prior to European settlement and active disturbance management practices (approximately 1910), disturbances in the form of fire were larger in extent, more frequent, and of lower intensity than present-day fires. Frequent low-intensity fires at average intervals of between 5 and 30 years favored retention of long-lived, fire-dependent, and fire-resistant species, such as ponderosa pine and western larch (Arno 1988, Arno et al. 1997, Camp et al. 1996).
Frequent, low intensity fires also resulted in more continuous “cropping” of developing trees and resulted in more open, park-like conditions (Everett et al. 2000). Burning in a patchwork pattern, most of the soils and vegetation experienced light disturbance retaining relatively open stands of very large ponderosa pine and western larch. Understories consisted of a diverse assemblage of fruit bearing shrubs, hardwood trees, grasses, and forbs (McCune 1983, Arno and Peterson 1983). Historical fires were frequent enough to keep fuel loadings light and reduce the hazard of stand-replacing fires across all stand types. Seral stands of large old ponderosa pine and western larch dominated nearly 25 million acres between central Montana and the Cascades of Washington and Oregon (Losensky 1995).
Historical fire patterns showed high temporal and spatial variability in both patterns of occurrence as well as their affect upon the landscape. Klenner et al. (2000) modeled forest community dynamics using the Tool for Exploratory Landscape Scenario Analyses (TELSA). They found that natural disturbances, in this case wildfire, created high levels of spatial and temporal variability with stands having different species compositions and age structures. In their simulations, which were based on old-growth stands in south-central British Columbia, historic levels of wildfire affected an average 525 hectares per year with a high annual variability.
While there is little available information regarding historical effects of other types of disturbances, it is likely that they too exhibited a similar pattern. Disease and insect occurrences were also affected by fires. Frequent historical fires prior to 1900 may have reduced insect and pathogen effects (Morgan et al. 1994). More “recent” historical disturbance patterns (35 to 50 years ago) are summarized by Lehmkuhl et al. (1994) and Hessburg et al. (1999).
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Portion of Riparian Ecosystems in Climax and Early Successional Conditions Under historical conditions with more frequent and less severe disturbance patterns, there would have been a greater proportion of early successional stages and greater landscape heterogeneity (Lehmkuhl et al. 1994). However, Camp (1996) and Camp et al. (1996) found that not all areas within a heterogeneous landscape have the same potential to reach late successional compositions and structures. Individual sites or patches can have specialized topography and moisture conditions that may lengthen fire return intervals, creating fire refugia. In a study at the Swauk Late Successional Reserve in Eastern Washington, such fire refugia were likely to occur on north facing aspects above 4,000 feet elevation and at the confluence of two perennial streams, within a valley bottom, on a flat bench, or within a drainage highwall (Camp 1996).
Historical landscapes were not likely in “equilibrium” conditions. Whenever a single disturbance event can affect a relatively large proportion of the landscape, achievement of an equilibrium state is not likely. There will be wide swings from one decade or century to the next in the proportion of the landscape in different developmental stages (Sprugel 1991). Historically, low-elevation forests of the Pacific Northwest fit this model, where individual fires may have covered hundreds of thousands of acres in pre-settlement times (Franklin and Hemstrom 1981).
While there is little specific information about historical successional patterns following disturbances, some current research may provide insights into how such systems might have responded. In the case of fluvial disturbances, the effects are greatest in the central core of the riparian ecosystem and diminish outward to the uplands. If this event scours the stream to bedrock, the rate of recovery depends upon the rate of coarse organic debris (COD) replenishment (rapid with large riparian trees and bank instability) that influences channel morphology and the routing of sediment and water (Franklin et al. 1981). The riparian area may then work as a “refuge” for certain types of species (e.g., shade-intolerant) (Naiman et al. 1993).
After a stand replacing debris torrent, the riparian successional sequence is analogous to understory development in upland old-growth Douglas-fir forest: early species richness and structure, mid-successional decline in understory production and richness, and late- successional increases in multi-layered structure (Huff 1984). Other disturbances complicate the prediction of forest community response to flooding disturbances in riparian areas. Fires and wind affect uplands primarily, but tend to enter the riparian system depending on the disturbance magnitude or width of the riparian area.
Russell and McBride (2001) studied what physical factors, both static and dynamic, influenced the balance between conifer and hardwood dominance in mixed conifer riparian systems and found proximity to the stream channel to be the most important factor. To a lesser extent, the time since the last fire was also shown to exert an influence on many of the same aspects of stand composition. High soil moisture favored hardwoods and potentially suffocated the roots of intolerant species. Recurrent flooding, and associated COD, damaged standing and susceptible trees. RIPARIAN DISTURBANCE REGIMES IN EASTERN WASHINGTON Concurrent Technologies Corporation - 40 -
Question 6
Historically, what was the distribution of stand characteristics (basal area, height, density, age, species diversity, canopy closure) by stand type in upland and ecological riparian communities? Response Available Scientific Information Scientific information on historical stand structure (greater than 100 years BP) in Eastern Washington is scarce, but indicates that tree densities, basal area, and representation of shade tolerant species were significantly less in historical Douglas-fir, ponderosa pine, and grand fir forest series. Currently the greatest information gap is on historic stand characteristics within high elevation forest types (e.g., subalpine fir and Engelmann spruce).
There are two types of information available on historical stand structure in Eastern Washington: 1) recent historical information (1940s) from aerial photograph analysis and 2) pre-European settlement historical information from stand reconstruction and age class studies (Everett et al. 1997, Harrod et al. 1999, Camp 1999). These information sources are supported by stand information used by Lillybridge et al. (1995) and Kovalchik (in press) in their vegetation classifications of pristine, undisturbed upslope, and riparian forests. Stand structure information may be a surrogate for historical conditions, especially in those forest series with long-duration fire return intervals (e.g., subalpine fir and hemlock-red cedar).
Recent large-scale resource assessments (Eastside Forest Health and the Columbia River Basin) used aerial photography to define historical conditions (Lehmkuhl et al. 1994, Hessburg et al. 1999). The use of “recent historical” (1940 aerial photographs) provides a glimpse of stand and landscape structure already significantly altered from pre-European settlement conditions; these altered 1940s-conditions may not be supported by inherent disturbance regimes.
Scientific studies have described a limited sample of historic stand structures for several forest series in Eastern Washington. It may be possible to use reference stands from vegetation classification work to get an improved idea of the array of conditions present prior to European settlement. Historical Stand Characteristics In general, the data indicate that significant changes in forest stand and landscape structure have occurred from the 1940s to the present and from pre-1900 to the present. Data indicate that forest stand conditions during early European settlement were less dense (fewer trees and less undergrowth) with larger, more shade-intolerant trees than at present. Some notable stand characteristic data are presented below.
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Basal Area • Basal area in Douglas-fir/ponderosa pine series on the East slope of the Cascades has continued a steady increase through 1999 (Ohlson et al. 2001 unpublished research). • No historical research information on basal area for mixed conifer or high elevation forest types was found.
Density • Tree densities increased from historical (100 years BP) for most size classes in both wet and dry sites on the east slope of the Washington Cascades while differences in tree densities between wet and dry forest settings declined from historical to the present (landscape homogenization) (Everett et al. 1997). • Dry ponderosa pine stand reconstruction studies show a significant increase in stand density from historic conditions (Covington and Moore 1994, Covington and Moore 1992, Arno 1988, Harvey et al. 1994). Other data indicate that following increases in stand density prior to 1950, tree densities started to decline in numerous PAGs in Douglas-fir/ponderosa pine series on the east slope of the Cascades after the 1950s (Ohlson et al. 2001 unpublished research). • Harrod et al. (1997) estimated historical (140 years BP) Douglas-fir tree density at 27 to 68 trees per acre and basal area at 10.3 to 22.3 square feet per acre among PAGs in dry ponderosa pine and Douglas-fir series on the Eastern Cascades of Washington. • No historical research information on stand density for high elevation forest types, such as subalpine fir or Engelmann spruce, was found.
Species Diversity • Recent historical information on stand structure suggests that some watersheds had significantly less shade-tolerant understories in grand fir, Douglas-fir, lodgepole pine, and ponderosa pine forest series (Lehmkuhl et al. 1994, Hessburg et al. 1994, Hessburg et al. 1999). Selective harvesting of shade-intolerant species in some areas (e.g., the Swauk Late Successional Reserve) has further exacerbated this shift in forest species composition (Camp 1999). • Some shade-tolerant species (e.g., true firs and Douglas-fir) have increased in number at a greater rate than other species (e.g., ponderosa pine, western larch, and lodgepole pine). • White pine blister rust has significantly reduced white pine representation and added to the dead wood component in inland forests (Harvey et al. 1994). Stands once dominated by white pine are now occupied by Douglas-fir, grand fir, white fir, and western hemlock.
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Other Stand Characteristics • In dry ponderosa pine forests in Eastern Washington, tree diameter distribution has shifted to smaller trees in current stands (Harrod et al. 1999). • Root rot pockets were more isolated historically; therefore, smaller patches of dead and down trees may have been present. • With reduced duration of insect outbreaks, fewer standing dead trees would have been evident in historic stands. • Under historic fire regimes, there would have been a greater proportion of early successional stages and greater landscape heterogeneity (Lehmkuhl et al. 1994). • Variability in fire return intervals indicate that there were patches with overstory and dense understory, but their proportion of the landscape was much reduced compared to present conditions (Everett et al. 1996). • A significant increase in dead wood occurred from 1710 to 1993 (Harvey et al. 1994). • No information was evident in the literature for historic height, age, or canopy closure.
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Question 7
How did the disturbance patterns in ecological riparian and upland communities differ? Did this vary by stand type, channel morphology, or stream size? Response Disturbance Patterns in Riparian Communities Forest riparian ecosystems are corridors of disturbance that maintain a reservoir of disturbance-oriented plant species within a matrix of less frequently disturbed upland forest. Riparian areas are considered both sensitive to and products of drastic disturbance (Thomas 1979). The combination of disturbance type, frequency, and magnitude produces either a relatively stable distribution of riparian plant communities over time or creates periods when early or late successional species dominate (Agee 1988). Edges of the riparian system are often buffered from upland disturbances such as fire or wind and to some extent from fluvial processes. Thus, a typical forested riparian system will experience fewer disturbances by upland mechanisms and increasing disturbances from fluvial processes. These relationships result in a riparian ecosystem with diverse species composition and structure.
Riparian areas have historically been subject to fire as an important element of their natural ecology (Arno et al. 1995). The magnitude and scale of effects are related to the size and severity of the fire; geology; topography; size of stream system; and the amount, magnitude, and timing of post-fire precipitation events (Swanson 1981, Meyer et al. 1992, Meyer et al. 1995). Areas where a large proportion of the watershed is burned in a single event are most susceptible to erosional processes with major channel alterations occurring in the first ten years after fire (Swanson 1981, McNabb and Swanson 1990, Minshall et al. 1997). These intensive fires can result in scouring of stream channels and destruction of riparian vegetation essential for providing stream shade, COD, and wildlife habitat (McGreer 1996). In some instances where COD was burned, severe increases in stream sediment transport and degradation have been documented in the absence of overland flow or debris torrents (Troendel and Bevenger 1993). A significant literature is building with accounts of wildfires that resulted in nearly total destruction of riparian vegetation and desirable stream features (Kaczynski 1994, Helvey 1980). Examples of wildfires that have significantly affected riparian systems are:
• The Boise River wildfire complex produced bank scour, release of destabilized channel-stored sediments, and debris torrents that discharged an estimated 750,000 tons of sediment to the North Fork of the Boise River during the first summer rains after the fire. On an annual basis, this represented a sediment delivery of 2,600 tons per square mile, 104 times the long-term pre-fire rate (McGreer 1996). All living riparian vegetation adjacent to hundreds of miles of Boise River tributaries was killed.
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• In ponderosa pine near Yellowstone National Park, a 450 percent increase was observed in sediment from alluvial storage and streambanks four years after the complete wilderness watershed was burned. Riparian root systems and COD were damaged and near-stream vegetation was removed. • Anderson (1968), studying the Sundance Fire in Idaho, found that the fire destroyed extensive acreage of riparian vegetation next to the Pack River. Apparently, firestorms toppled trees into the river and burned hot enough to remove limbs to the water line (McGreer 1996).
Other types of disturbance, such as wind, are far more difficult to characterize as disturbance aspects in riparian systems. Windthrow potential is dependent upon local topography and forest structures. It is more important on poorly drained soils, wide valleys, and where riparian areas are oriented to the prevailing winds (Agee 1988). Tree tolerance to wind is site specific. Western hemlock is generally prone to windthrow. Western red cedar and Sitka spruce are at times wind-firm, while Douglas-fir is often described as both wind tolerant and wind sensitive. Stand dominants are often more wind-firm than intermediate crown-class trees (Gordon 1973). Disturbance Patterns in Upland Communities Differences in moisture condition, topographic position, and plant community type were assumed to increase fire frequency and reduce fire severity in upland versus riparian systems (Heinselman 1973, Agee 1994, Camp et al. 1997). For example, a high intensity, stand- replacing fire burned the Little French Creek in the Payette National Forest in Idaho while the lodgepole pine-covered upland was unburned, except for some downed logs (Williamson 1999). The 1970 Entiat Fire near Wenatchee, Washington burned the riparian system along the Entiat River completely, leaving scattered western red cedar. Agee (1994) found even- aged lodgepole pine in Eastern Washington riparian areas indicating a stand replacement fire in or near the riparian area while upland Douglas-fir and ponderosa pine showed evidence of frequent, low-intensity burning. In dry forests of the Blue Mountains, frequent fires burned consistently across the landscape through the riparian areas with a low severity fire regime due to gentle topography (Olson 2000). Skinner (1997) suggested that fire return intervals were twice as long in riparian reserves as in uplands.
In summer, upland areas will not retain moisture as long as nearby riparian areas, thereby increasing flammability and chances of ignition in upland areas (Olson 2000). The 1994 Tyee Fire near Wenatchee burned greater proportions of crowns in upland areas than in riparian areas (Morse 1999). By contrast, channeling of the wind along headwater riparian areas can produce a chimney effect and intensify fire within the riparian corridor (e.g., 1988 Dinkelman Fire near Wenatchee) (Agee 1994).
Some pests seem to prefer upland to riparian areas. Pandora moth has a patchy distribution that may depend on soil conditions; larvae appear to prefer loose upland soils developed from weathered granite or pumice where they can burrow to pupate (Furniss and Corolin 1977). Subsequent invasion of weakened trees from bark beetles sometimes leads to extensive tree mortality (Speer et al. 2001).
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Variation by Stand Type, Channel Morphology, and Stream Size Olson (2000) concluded that fire intervals were affected more by forest composition and overall climate than whether the fire occurred in riparian or upland forests. Agee et al. (1990) found fire intervals in POME/ABGR communities in low elevation riparian areas to be greater (93 years) than in PIPO/POME and PICO/POME upland communities (52 and 76 years, respectively). Fire was less frequent in lower elevations, bottomlands, and riparian areas (mean return interval greater than150 years compared to 114 years for the rest of the study). Heyerdahl (1997) and then Olson (2000) found that dry forests in the Blue Mountains did not vary in terms of fire recurrence due to aspect or elevation unless the terrain became more dissected as elevation increased, then fire return intervals began to lengthen. With increased elevation, forest composition changed in response to topography and elevation changes in temperature, and insulation was less as riparian valleys became deeper. Olson’s (2000) study showed that more mesic conditions result in longer fire return intervals.
The nature and magnitude of disturbance effects can be related to stream order (Agee 1988). In small streams (i.e., 1st order streams), the center of the stream channel zone has a high probability of disturbance by fluvial processes, either directly as the result of a precipitation event or indirectly from upland disturbance that results in sediment input upstream. The channel might be scoured by debris torrents and trees may be buried or undercut. First order streams have relatively small topographic depressions that often provide little additional protection from wind, and the microclimate modification is not much of a buffer against fire. The total probability of disturbance is greater in the riparian system than on either side (Agee 1988). This results in the upland forest dominating the riparian system, with enough core disturbance to maintain small populations of invader-type species such as red alder. After a landscape-level fire that might burn across the riparian system, red alder may persist for several decades until upland Douglas-fir, better adapted to burned sites that do not flood, overtops and eventually shades out the red alder. After crown closure, the vegetation structure may be similar between uplands and the riparian area.
In 3rd to 4th order streams, the probability of fluvial disturbance is high near the core zone and decreases outward. Deeper valley settings are likely to reduce the potential for windthrow, with the exception of the stream edge where undercutting of tree roots may increase windthrow potential. Fire potential decreases significantly closer to the stream channel. A disturbance gradient exists with a definite trough at the edge of the riparian system. Lower disturbance probability, or lower intensity disturbance if one occurs, is associated with dominance by later successional species such as western hemlock (depending on soil moisture) and western red cedar. Structurally, the riparian system may have large standing trees that are wind-firm and, when undercut and toppled, provide a continuing source of COD. Uplands are unlikely to have trees of the size of the riparian systems unless protected by disturbance for centuries. The riparian core is wide enough and disturbed by fluvial disturbance often enough that invader-type species dominate along the channel.
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that maintains a stable distribution of forest age classes (Agee 1988). Large valley floors are corridors for wind, making windthrow important across the floodplain. Species that are shallow rooted may experience blowdown in winter on saturated floodplain soils. Typically, fire is not a significant factor across large floodplains. Fluvial processes dominate the disturbance pattern and invader-type species, favored by disturbance, dominate the riparian plant community. On larger streams, fluvial disturbances are concentrated near the channel. Deep alluvial depositions in floodplains can alter the available water on a site. Rapid accumulations of organic materials can occur on wet meadows and overflow channels, altering the water holding capacity and nutrient availability of soil (Hansen et al. 1995).
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Question 8
What is the typical width of the area containing ecological riparian communities? Does this vary by channel morphology, stream size, valley characteristics, climatological patterns, or other factors? Response Width of Ecological Riparian Communities No “typical width” of the area containing ecological riparian communities was identified. The degree of riparian community development is related to the size of the associated river or stream system (Brinson et al. 1981, Leopold et al. 1964, Riparian Habitat Technical Committee 1985). Larger streams/rivers typically have well-developed, complex floodplains, with patches of standing open water in cutoff oxbows with a variety of plant communities, and deep, moist soils. Larger streams have less stream gradient, COD tends to be more randomly oriented and is less important geomorphically (Swanson et al. 1981b), and the riparian zone tends to be much wider (Agee 1988). Generally, “the river dominates the forest rather that the forest dominating the stream” (Agee 1988:35). Large valley systems influence the distribution of stream power into multiple channels in wider stream reaches. These larger valley systems typically have wide, well-developed riparian communities (Bendix 1994). Headwater streams have high topographic relief and restrictive substrate conditions. In these streams, riparian vegetation may be absent, thus restricting riparian wildlife habitat to the wetted portion of the riparian ecosystem. Even in areas of low relief, small streams will produce smaller riparian communities because smaller streams carry less water resulting in less influence on the area adjacent to the stream (Bilby 1988). Small streams tend to be dominated by the terrestrial system. The influence of the terrestrial system decreases with increased stream size since progressively larger pieces of wood are needed to form sediment terraces in larger channels (Bilby and Ward 1987). Fewer woody accumulations are found in larger systems and the impact of this material on stream structure is concomitantly lessened (Bilby and Ward 1987).
Prior disturbance events and valley geomorphic features supply the energy and material to create riparian landforms (Swanson et al. 1988, Wissmar and Swanson 1990) that define the spatial pattern, type, and successional development of riparian ecosystems (Rot 1995). Geomorphically, valley width influences the distribution of stream power and can constrain the width of both channel and riparian community. Riverine riparian ecosystems have evolved in a highly dynamic, unstable environment where devastation and destruction are normal components (Hall 1988). Large organic debris such as tree boles, root wads, and large branches retain sediment and gravels, both of which affect the shape of the channel. In stream systems bordered by steep terrain, sediment terraces formed behind woody debris serve to increase the size of the riparian area by forming wide, flat areas near the stream channel (Bilby 1988).
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The physical structure of the riparian ecosystem can be dramatically influenced by infrequent catastrophic events. High discharge accompanied by the battering action of floating debris or chunks of ice can alter the size of the riparian system by damaging or uprooting vegetation. Streambank erosion can undermine vegetation at the edge of the channel and cause it to collapse into the stream. The severity of these effects depends on riparian area topography, channel morphology, and the flood magnitude. Hydrologic regime alterations of large river systems (e.g., dams, irrigation diversions, dikes, and flow augmentation) have the potential to alter the size and characteristics of riparian communities. The release of large volumes of water at times of low flow can alter the composition of riparian communities. By contrast, flow control can eliminate or reduce inundation, with the result that soil conditions and water availability are altered and vegetation may become more like adjacent uplands (Ohmart et al. 1977). Soil fertility might be reduced by the elimination of periodic flooding with the associated deposition of fresh sediment (Bilby 1988).
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Question 9
What are the succession variables and timeframes for large tree regeneration following stand replacement fires (by stand type)?
Response Large Tree Regeneration Information on tree species growth rates relative to site quality is well established in the literature (site index curves). Also, information is available on relative growth rates of different species on the same site. Combining this information with a knowledge of inherent disturbance regimes (Question 1) and species avoidance, resistance, and resilience (Question 3) provides an estimate of the potential for large trees, the required timeframes, and the species that will be producing large trees most rapidly within a PAG. Silvicultural and prescribed fire treatments are available to maintain thrifty stands and sufficient growing space for rapid large-tree regeneration. Succession Variables Data indicate that both fire and insect infestation can redirect succession following stand replacement fires. Reoccurring fire can restart large tree regeneration or redirect succession to grass or shrub types of communities for extended periods. Stand development and successional models for forest series in Eastern Washington indicate the multiple fire opportunities that revert developing stands back to a shrub/forb/grass stage (Wischofske and Anderson 1983). Insects that prefer young seedlings or saplings as hosts (e.g., fir engraver, Douglas-fir engraver, and pine engraver) (Hessburg et al. 1994), could also affect the regeneration process. Mountain pine beetle attacking stressed lodgepole pine stands, when stem diameter exceeds 8 inches, would affect the capability of this species to develop a large tree component. Timeframe Required for Large Tree Regeneration For those areas where stand replacement has been complete, the regeneration of large trees is dependent upon the time required for species to re-establish at the site and the time required for the species to grow to a large size. The tree species that establishes rapidly following fire, has the fastest growing rate, occurs on the most productive sites, and for which development is not redirected by disturbance should provide large trees in the shortest period of time.
Some tree species are able to establish more rapidly than others following a stand replacement fire. The serotinous cones of lodgepole pine provide a ready post-fire seed source. Other species may have to depend upon seed immigration from adjacent unburned areas to re-establish. The re-establishment of aspen by suckering would hasten the process of achieving large trees of this species.
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Site quality also plays a significant role in the time required to generate large trees. Site index values use tree heights achieved at specific timeframes, usually 50 and 100 years for conifer species, to estimate site productivity (Cochran 1979). Those sites with the greatest productivity will produce large trees faster than low productivity sites. A comparison of site index curves among various conifer species for an area would give an estimate of which species grow faster than others. For each forest series and PAG, one species may have a better growth rate than another. Lillybridge et al. (1995) developed site index values for the tree species growing together within the various plant associations on the Wenatchee National Forest.
Everett et al. (1999) presented an example of regeneration of large trees following wildfires for a chronosequence of burns in Eastern Washington. Although lodgepole pine had the fastest establishment rate (10 years), its slower growth rate and poor site quality meant that it did not produce a tree 23 to 41 cm diameter breast height (dbh) for 54 years, and it did not produce trees greater than 41 cm dbh on these sites. Douglas-fir took longer to become established on the sites following fire, but produced large trees in a shorter timeframe than ponderosa pine. Decay rates for Douglas-fir and ponderosa pine were faster than for thin barked species (e.g., subalpine fir and Engelmann spruce) so that recruitment snags were produced faster as well (Everett et al.1999).
Excessive regeneration and the absence of disturbance during stand initiation and stem exclusion phases may actually limit the rate of large tree regeneration. Stand stagnation because of limited growing space lengthens the time required to produce large trees. Thinning by fire, insects, pathogens or mechanical means frees up site resources for additional tree growth (Question 11). Stands that are maintained below the maximum stand density index (SDI) (Cochran et al. 1995) will have the greatest growth potential for large trees.
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Question 10
What is the typical tree survival rate following a stand replacing fire or understory burn? How much standing wood (live and dead) remains after fires of varying intensity? How much wood typically remains on the ground? Response Tree Survival Rates No document that defines the typical survival rate following a stand replacement or understory fire was identified. Tree mortality is a species, stand, and landscape specific phenomenon that changes with amplitude of fire disturbance applied. Rather than searching for a mean mortality estimate with limited applicability, a more fruitful approach would be to use current predictive models (e.g., FIRESUM) validated on forest stands similar to those of interest to this study (Tholen 1999).
There is no ”typical” amount of burned and unburned trees within a post-fire landscape. Tree survival following fire is dependent upon the magnitude of the disturbance (fire intensity), tree resistance, avoidance, and post-fire insect mortality. Question 3 addressed tree resistance and avoidance in detail. In summary, those tree species that grow on “safe” sites that do not burn readily (e.g., talus slopes and headwalls) (Camp 1996), avoid fire effects. Species growing where fuel loading is light or moist (e.g., western red cedar) have reduced fire intensity applied. The fire connectivity between upslope and riparian forests is such that riparian areas have the same heterogeneity in burn conditions as upslope forests (Scher 1991). Surface Fire Mortality Tree mortality is a function of several factors: percent of live crown scorched or killed, cambial damage in stems and roots, duration of lethal heat, and critical time for crown kill (Peterson and Ryan 1986). The relationship between fire damage and tree mortality has been described for ponderosa pine (Dieterich 1979) and Douglas-fir (Bevins 1980).
Swezy and Agee (1991) used a model developed by Peterson and Ryan (1986) to estimate the sensitivity of different tree species to scorch height and fuel bed properties, and then to estimate probable mortality rates for each species in a Douglas-fir stand. Mortality was estimated at 100 percent for subalpine fir, grand fir, Engelmann spruce, and lodgepole pine. No mortality was estimated for ponderosa pine or western larch. Young ponderosa pine may survive up to 75 percent crown scorch with only 25 percent mortality, but old trees may show poor survival (Swezy and Agee 1991). The predictions from the model are in general agreement with estimates of individual tree fire resistance.
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Stand Replacement Fires By definition, a stand replacement event reduces the basal area of the site by 70 percent or more (Agee 1994). The percent mortality in stand replacement events varies based on the heterogeneity of the forest landscape and the burning conditions (Agee 1993). Although differences in stand structure and topography create heterogeneous post-fire landscapes (Tholen 1999, Scher 1991), severe firestorms may ignore vegetation and topographic differences resulting in more uniform mortality over extended areas (Swanson 1988). Quantity of Standing Wood Following a Fire The quantity of standing wood following a fire is dependent upon fire severity, quantity of biomass present at the time of the fire, site potential (stand and topographic characteristics), and species resistance to fire. For example, it is estimated that little standing dead wood is likely to exist after a low severity fire in dry ponderosa pine/Douglas-fir forests (Mutch 1970), while low severity fires in stands of white fir, hemlock, or red cedar that are sensitive to root charring (Starker 1934) may create a significant standing dead wood component.
Low intensity fires are increasingly rare because of excessive fuel loads (increased tree density and mortality) in all forest types. The probability of high intensity fires has increased for areas that have inherent low severity or mixed fire severity regimes. Therefore, the proportion of dead to live tree biomass following fire should be increasing. The proportion of dead to live wood increases with fire severity. Quantity of On-Ground Wood Following a Fire Snag fall-down rates are species, diameter, and site specific (Dahms 1949, Raphael and Morrison 1987). Ohlson (personal communication) found that snag fall-down rates (percent down per unit time) for Douglas-fir decrease with tree diameter. For large ponderosa pine and Douglas-fir snags, the tops fall as well (Everett et al. 1999). Data indicate that small- diameter Douglas-fir and ponderosa pine fall more readily than those of subalpine fir, lodgepole pine, or Engelmann spruce (Everett et al.1999). Therefore, post-fire log fuel loadings should increase rapidly where these species predominate (Everett et al.1999).
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Question 11
What are the disease and drought (climatic variables) influences in thinning thick stands? Response Thinning in Riparian Forests No literature specific to the influences of pest and drought in thinning dense riparian forest stands in Eastern Washington was identified. Since riparian and uplands share a majority of the same plant associations, extrapolation of upslope research into riparian areas may be valid, with some caveats. Soil moisture stress would likely be less within riparian areas. However, with the potential for increased biomass (untested assumption) and less drought tolerant species, drought effects may be equal to those upslope. If the riparian areas have the capacity to grow forests faster because of elevated water availability, then critical SDI values (upper stocking density) may be reached faster and require stocking control sooner than in adjacent upslope stands. Natural Thinning of Thick Stands Thick stands develop because natural regeneration and reforestation practices generally provide more seedlings per area than can be supported as trees grow and completely occupy the site. Thick stands progress through a number of developmental stages. Stem exclusion is the developmental stage where competition among existing trees prevents the establishment of more seedlings (Oliver and Larson, 1990). Seedlings and saplings usually die first and can succumb under moderate drought conditions (Joyce et al. 2001). As stress increases, the less vigorous trees may die and remaining trees compete for their vacated growing space. This self-thinning process results in a reduced number of larger trees with increased vigor to resist drought and ward off insect and pathogen attack. This natural thinning process can be repeated if shade tolerant understory eventually overtops shade intolerant species (stem re- initiation phase) (Oliver and Larson 1990).
The timing for the stem exclusion phase and subsequent self-thinning varies by forest type, stocking levels, site quality, and environmental conditions (Oliver and Larson 1990). The stem exclusion phase is a time of stand stress, where weak trees are susceptible to insect and pathogen attack. Fir engraver attack on grand fir is prolonged on sites subject to extended drought (Adams 1994). Douglas-fir may be predisposed to root rots and bark beetle infestations because of reduced vigor due to competition for light (Adams 1994). As thick stands thin, the increase in dead and down from tree mortality adds to the fuel bed and elevates fire hazard. Silvicultural Thinning Techniques Foresters have developed thinning techniques. Five general thinning methods are recognized to redistribute growth potential and restructure stands (Graham et al. 1999):
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• Low, or thinning from below: removal of suppressed and intermediate trees. Thinning from below most closely mimics tree mortality from surface fires or inter- tree competition during stem exclusion. • Crown, or thinning from above: removal of dominants and co-dominates to favor selected species (Nyland 1996 in Graham et al. 1995). Crown thinning maintains vertical structure and can increase growth of remaining dominants for wood production or wildlife habitat. • Selection, or diameter-limit thinning: removal of dominates to favor smaller diameter trees. Selection thinning removes dominant trees and perpetuates insect or pathogen problems associated with the understory species. • Mechanical thinning: removal of trees based on spatial location. Mechanical thinning is applicable in plantations where desired tree spacing is maintained for maximum growth during stand development. • Free thinning: selection of specific trees for retention regardless of position in stand structure. Free thinning is designed to release specific trees within a stand and provides maximum flexibility in designing future stand structure. Silvicultural Thinning of Thick Stands Thinning is a process to reduce the stocking level of forest stands, with the goal of creating fewer, more vigorous trees that grow faster and are more resistant to insects, pathogens, and drought. Eastern Washington forest stands are thinned to:
• Maintain desired species • Maintain tree vigor for growth • Increase resistance to insects and pathogens • Reduce continuity in host species for pathogens • Reduce fire hazard
Thinning and resultant tree vigor and growth may reduce the hazard to drought, insect attack, pathogen infestation, and reduce fire hazard by removing ladder fuels and elevating the crown.
In almost every case, insect and pathogen infestations are mitigated by reducing stand density, especially if the host conifers are discriminated against. With defoliating insects, it’s important to reduce both horizontal and vertical stand density. With bark beetles, basal area is the key to hazard reduction and with dwarf mistletoe host-specific thinning should be used to reduce the stand dwarf mistletoe rating. (P. Flanagan personal communication).
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Some observed benefits of thinning to specific tree species include:
• Both ponderosa and lodgepole pine stands avoid mortality from bark beetle attacks (Cole and McGregoor 1988). • Western larch stands are able to have sufficient height growth to exceed the upward advance of dwarf mistletoe (Wicker and Hawksworth 1991). • Western larch stands benefit from reduced budworm damage because larger diameter shoots are severed less often and vigorous trees are better able to recuperate rapidly (Schmidt and Fellin 1973, Schmidt et al. 1976).
Cochran et al. (1994) and Schmitt (1999 unpublished) provide information on desired stocking levels and the benefits associated with those stocking levels in reducing forest health problems. Application of Thinning Techniques in Thick Stands Stocking guides use basal area to evaluate growing space; however, basal area may not be the most useful measure for this purpose. Cochran et al. (1994) suggested stocking levels for forest stands in Eastern Washington and Oregon using a SDI that is independent of site quality and stand age. The goal is to define an upper density limit at which a suppressed class of tree begins to develop and manage the stand so that this density does not occur (approximately 75 percent of SDI). The SDI threshold for mountain pine beetle mortality of lodgepole pine appears to be around 165 to 170 (Peterson and Hibbs 1989, Mitchell et al. 1983). SDI values as presented by Cochran et al. (1994) are for specific plant associations. SDI values vary by plant association. An alternate approach developed by Perry (1995), called the “self-thinning rule,” uses average plant size density and maximum size density to guide thinning.
Classification schemes developed by entomologists and pathologists may be useful in identifying forest problem areas and setting priorities for preventive activities such as thinning to reduce drought, insect, and pathogen hazard. Entomologists and pathologists have developed various hazard and risk rating systems in an attempt to evaluate and possibly control insect outbreaks and pathogen epidemics (Jurgensen et al. 1994). For example, Amman et al. (1977), Mahoney, (1977), and Schenk et al. (1980) developed various classifications based on different aspects of beetle-host-site interactions. Variables used include elevation, latitude, average stand age, average dbh, resistance to infestation, and pathogen infection. Effectiveness of Silvicultural Thinning of Thick Stands Thinning stands may or may not alleviate drought stress and subsequent insect, pathogen, or fire hazard. For thinning to be effective, it must remove or ameliorate the stand structural component and or species associated with the hazard. Is the hazard associated with the understory trees? These are suppressed trees with crowns below the dominant tree crown or intermediate trees with crowns into but shaded by the dominant/co-dominant trees (Oliver and Larson 1990). For example, with an understory of Douglas-fir and grand fir and RIPARIAN DISTURBANCE REGIMES IN EASTERN WASHINGTON Concurrent Technologies Corporation - 56 -
ponderosa pine dominants, the fir confer a higher pathogen and fire hazard to the stand. Thinning from below (removal of the understory) is appropriate, as it would reduce drought stress, ladder fuels, and continuity in host species for pathogens and insects of the fir species. Alternatively, is the hazard associated with the co-dominant and dominant trees in the overstory, as could occur with mistletoe infestation? Thinning from below in stands where the overstory has a high level of mistletoe infestation would only pass the mistletoe infestation to the post-thinned understory component (Hessburg et al. 1994). Thinning within the mixed conifer type requires careful planning. Thinning from above in dense stands of Douglas-fir and grand fir only perpetuates the shade tolerant fir and host continuity for pathogens and insects with elevated fire hazard from low crown base height and high crown bulk densities (Brown 1978). Graham et al. (1995:22) concluded that “thinning from below and possibly free thinning can most effectively alter fire behavior by reducing crown bulk density, increasing crown base height, and changing species compositions to lighter crowned and fire-adapted species.” Stocking control can prevent suppression-related mortality, reduce the severity of dwarf mistletoe infections, and lower mortality caused by mountain pine beetles (Cochran et al. 1994).
Thinning is not without risks. Fuels increase, wind speed increases, and fuels dry out more rapidly from canopy openings (Rothermel 1983). Thinning may increase blowdown problems in those stands with species susceptible to windfall, such as lodgepole pine (Adam 1994). Stumps left following thinning may also increase disease infestations if not managed carefully (P. Flanagan personal communication). Thinning in riparian forests may pose additional risks. “Thinning in moist forests should be approached carefully. Any approach to reduce crown fire potential and improve health should be tied to the active restoration of early seral species” (Graham et al. 1999:20).
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Question 12
Are there other ecological features, such as exotic plants and predation, which may direct an upland or riparian community into a new path of succession? Response
Redirection of Riparian and Upland Communities by Ecological Features Riparian and upland communities are affected by animals and exotic plants through predation, competition for resources, and alteration of habitat. These affects may be of sufficient magnitude to redirect successional paths. Influence of Animals on Forest Community Succession Animals can redirect forest succession through predation and alteration of habitat. Predation, in the form of herbivory, directly influences mortality and recruitment in forest communities. If herbivory is excessive, vegetation can be degraded, altered, or eliminated (Oakley et al. 1985). Herbivory also has indirect effects (e.g., increases in temperature and available light at the forest floor by defoliation that promotes understory growth, seedlings, and herbaceous plants). Site productivity, slope, elevation, burning, and herbicide treatments all have the potential to affect the intensity and frequency of predation (Boyd 1985). Both wild and domestic animals alter forest habitat. A significant literature has built up surrounding animal damage research in the Pacific Northwest (sensu Crouch 1987). Data indicate that ungulates, beavers, and other mammals can have significant affects on forest communities.
Ungulates Impacts by large ungulates can be categorized into five areas: 1) soil compaction that might increase overland flow and decrease water availability to plants; 2) plant removal that lowers plant vigor and changes competitive interactions among other plant species; 3) physical damage to vegetation by rubbing, trampling, and browsing; 4) changes in fluvial processes produced by herbage removal; and 5) physical streambank changes which may lower water tables and/or cause a decline in invasion sites for riparian plant establishment (Kauffman 1988). Excessive browsing of young trees by ungulates reduces the reproduction of riparian trees (Glinski 1977, Kauffman et al. 1983). Without recruitment of young trees into the population, unstable age structures might result and these populations may eventually be eliminated. Moderate, prolonged grazing or browsing pressures may shift the normal primary succession sequence of hardwood-conifer back to a disturbance-caused cottonwood condition. Severe, prolonged grazing and browsing pressures may eliminate all conifer and deciduous seedlings and may eliminate understory shrubs as well (Hansen et al. 1995). In this situation, the overstory cottonwood continues to mature and the site becomes open with an herbaceous understory. Eventually the stand becomes decadent with widely spaced, dying cottonwoods. The site then becomes so open and dry that it is subject to invasion by nearby upland plant species. COD inputs will be reduced with a concomitant alteration of
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hydrologic properties. In turn, this hydrologic change will further influence successional processes, changing the composition and structure of riparian vegetation.
Beavers Beavers are obligate riparian residents that can change site characteristics by building dams and alter species composition (and thereby succession) by over-utilizing food supplies. Mass starvation may result from a decline of staple food supplies, leading to a new successional trajectory away from woody vegetation (e.g., alder and willow) and creating a sedge-grass meadow (Hall 1988). Beaver dams, in series, can significantly slow water flow and raise stream base levels, leading to higher water tables. These high water tables might influence the survivability of water-tolerant but not obligate plants. These plants could die and/or fail to reproduce, eventually being eliminated from the riparian community. For example, a conifer stand growing on a first terrace would be killed by anoxia or disease and be replaced by sedges due to beaver dam flooding. A change in the base level of a stream can alter the competitive ability of plants, resulting in major shifts of species dominance and composition. Long-term persistence of these dams creates new substrates that restart or redirect successional trajectories.
Other Mammals
Animal damage has the greatest impact on regeneration, particularly on sites where habitat favors high animal populations or high use by wildlife. Injury from rubbing, trampling, and burrowing adds to the damage problem. For example, wild and domestic mammals adversely affect ponderosa pine by feeding on, injuring, and killing seedlings, saplings, and small trees. At the patch scale, pocket gophers (northern and Mozama) can limit successful regeneration of ponderosa pine by clipping and killing seedlings and saplings. The magnitude and duration of this interaction is a function of both disturbance history and plant community succession. In severe disturbances (Green et al. 1987), pocket gopher density can reach more than 6,000 mounds per acre. Influence of Exotic Plants on Forest Community Succession
Ecologically, a weed is defined as an exotic colonizer or a pioneer species of open or disturbed habitats, frequently from anthropogenic activities (Taylor 1990). Weeds are often tenacious and can displace native flora and fauna. Much effort has gone into managing competitive vegetation in managed forests (Baumgartner et al. 1986). A characteristic feature of open and disturbed lands is the invasion and establishment of early successional or seral plant species. Many of these early seral species are weeds, particularly in human disturbed areas such as roads and areas where logging, livestock grazing, and recreation are present. Weeds are successful because of a combination of adaptive morphological and physiological characteristics (Harrod et al. 1993). During the 1970s when timber management in Eastern Washington shifted to intensive, even-aged management, more roads and large openings were created that provided light and delivery systems for weeds. These changes also resulted in more foraging and/or loitering sites for large herbivores.
Neuenschwander et al. (1986) developed a conceptual model of early succession after disturbance that incorporated the critical influences affecting the successional response for RIPARIAN DISTURBANCE REGIMES IN EASTERN WASHINGTON Concurrent Technologies Corporation - 59 -
“key” competitor species that may be adaptable to invasion and redirection of succession by an exotic colonizer. Environmental conditions, existing vegetation, life history, ecology of the species available for colonization, kind and severity of the disturbance, and chance were identified as the major influences on successional patterns following disturbance. Critical successional processes were the determination of the initial flora, establishment, growth, and biotic interactions.
Effect of Exotic Plants in Riparian Communities Streams often provide a vehicle for dissemination of both terrestrial and riparian plant seeds, further influencing the composition and distribution of streamside vegetation (Daubenmire 1968). Although noxious weeds such as knapweed (Centaurea spp.) and leafy spurge (Euphorbia spp.) along a streambank might help to trap and provide deep soil-binding properties necessary for maintaining the streambanks, their presence is a management concern and indicator of poor health (Hansen et al. 1995). Riparian communities are vulnerable to invasion by exotic weeds. Regular floods decrease the strength of competitive interactions and periodically return parts of riparian systems to early successional stages, providing a diversity of microhabitats on a shifting mosaic of landforms (Pollock et al. 1998, Gregory et al. 1991, Wissmar and Swanson 1990). These factors promote high plant species richness but may also increase susceptibility to invasion by weeds (Pysek and Prach 1994). Anthropogenic disturbance frequently introduces weeds to riparian communities and natural disturbances can facilitate their spread throughout the stream network. The availability of water and the potential for weed dispersal throughout the network may work synergistically to promote weed invasion (Hood and Naiman 2000). Given that exotic species affect ecosystem processes (Ramakrishnan and Vitousek 1989), there is cause for concern about the extent and effects of weed invasions on riparian systems.
Hood and Naiman (2000) have assigned the potential for weed invasion to two separate riparian landforms: the macro-channel floor, frequently disturbed by seasonal flooding, alluvial sediment redistribution, and browsing by animals, and the macro-channel bank, with steeper slopes, rarely disturbed by floods, containing no alluvium, and browsed by animals. Plant species on the macro-channel floor and low on the bank are exclusively riparian, while high on the bank, upland species are included. In a comparison of two Pacific Northwest rivers, one South African river, and one French river, Hood and Naiman found exotic species to range from 5 to 11 percent on the macro-channel banks and 20 to 30 percent on the macro- channel floors. This suggests that frequently flooded active channel floors are more vulnerable to weed invasion than the more stable and steeper banks, and that, on the average, the macro-channel floor is three times more susceptible to invasive species than the macro- channel bank.
That riparian systems are the principal mechanism by which exotic plants can invade sites with little anthropogenic disturbance has been shown in arid and semiarid game preserves of South Africa, national parks in Utah, and in Mediterranean climates of France and California. The vulnerability of riparian systems to invasion by weeds is similar in a wide variety of rivers (Hood and Naiman 2000). Mechanisms that promote weed invasion in riparian systems have associated steps in the invasion process: 1) the availability of stream water for the transport of propagules that promotes dispersal to a site appropriate for germination, 2)
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the frequency and intensity of flooding that provides for germination and establishment with reduced competition, and 3) water availability from the water table that insures rapid growth and reproduction success. Disturbance, flooding in particular, has been correlated with successful weed invasion. Successionally, young areas that experience frequent flooding have a higher percentage (Planty-Tabacchi et al. 1996) or number (DeFerrari and Naiman 1994) of weeds.
Notable Exotic Plant Species in Eastern Washington Knapweeds are one of the most important forest weeds in Eastern Washington. Twelve out of fourteen introduced species of the genus Centaurea have demonstrated adaptability to habitats in Washington (Roche and Talbot 1986). Diffuse and spotted knapweeds are the most serious infestations on Eastern Washington forestlands, with diffuse knapweed demonstrating the greater ecological amplitude. Roche (1988:123) stated that “those Eastern Washington forestlands that are not farmed or managed are likely to be diffuse knapweed dominated during some part of their early- to mid-seral stages.”
Russian olive (Elaeagnus angustifolia), a tree native to southern Europe and western Asia, was introduced into North America during colonial times (Elias 1980). Russian olive was planted in shelterbelts due to its dense growth form, hardiness, and adaptability to a wide range of soil and moisture conditions (Olson and Knopf 1986) and its use for ornamental and wildlife plantings, erosion control, and highway beautification. Russian olive is naturalized throughout the 17 western states. A review of the literature indicates that the naturalization process is rapidly increasing with substantial impacts to floodplain forests (Hansen et al. 1995). The tree has the potential to redirect succession by complete replacement of native riparian plants. This replacement of native species by dense thickets of Russian olive can result in a 30 percent reduction of breeding bird species (Knopf 1991). These dense stands and low palatability limit access by browsing animals, reducing most forms of predation. Russian olive, spread by birds and small mammals, favors establishment on soils with spring moisture and slight alkalinity. Once established, it is difficult to control and nearly impossible to eradicate. It has become a management concern for many riparian areas throughout the Pacific Northwest (e.g., Barker Ranch, Wetland Enhancement Program, and Yakima River, Washington).
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Question 13
Some portion of the areas affected by stand replacing fires will reburn before the forest is re-established. What portions of those areas are expected to be affected by the reburn? What is the effect of the reburn on forest recovery? How much wood typically remains standing or on the ground following the reburn? Does this vary between upland and ecological riparian communities? Response Forest Reburn Events Reburn events following stand replacement fires are surface fires by definition as tree crowns are no longer present. For a reburn to occur, there must be sufficient fuels to carry the fire. Since the first fire (prior to the reburn) removed the tree crowns, surface fuels such as deadwood, understory biomass, and tree seedling/juvenile biomass are required for a reburn to occur. Therefore, the second fire or “reburn” will be a surface fire and its extent will be defined by continuity in surface fuels, topographic effects, and climatic conditions. Reburns should emulate historic surface fires in extent, and perhaps frequency, for forest types in the mixed and low severity fire regimes, with the caveat that the additional dead and down materials in the form of fallen snags from the first burn may increase the rate of fire spread during the reburn. Following a reburn, a forest is considered re-established when the tree component of the forest is dominant and is suppressing understory shrubs and grasses. Occurrence and Extent of Reburn Numerous authors have assessed the reoccurrence of fires over time for dry grand fir, Douglas-fir, and ponderosa pine forest types in Eastern Washington and Oregon (Wright 1996, Olson 2000, Everett et al. 2000). These data indicate that fires sequentially reburn portions of previous fires and sometimes reburn the entire area affected by the first fire prior to re-establishment of the forest (Schellhaas et al. 2000). The frequency of these fires and their extent suggest that there is a high potential for consecutive reburns. The frequency, extent, and severity of reburns should be dependent upon the characteristics of surface fuels and the fire regime of the area.
The potential for reburn prior to re-establishment of forests is limited to those forest series with low severity, high frequency fire regimes and mixed severity fire regimes. Although, there is little information on reburns, the character of surface burns in these forests may provide useful information for reburns within these forests. Again, this is with the caveat of increased fire intensity from dead and down material.
No specific information on the proportion of a stand replacement fire that reburned prior to tree establishment was identified. Stand replacing fires would likely remove much of the fire scar record and trees that would be capable of recording the reburn fire date. Given the extended fire return intervals (greater than 100 years) for some forests types (e.g., subalpine fir, Pacific silver fir, mountain hemlock, western hemlock, and western red cedar) reburns prior to forest re-establishment are not likely to be a significant issue in these forest types.
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Reburns are more likely to occur prior to stand establishment in those forest types where the fire return interval is shorter (e.g., dry grand fir, lodgepole pine, Douglas-fir, and ponderosa pine). However, no literature was identified that estimated the proportion of stand replacement fire areas that reburn prior to tree establishment for any forest series. Effect of Reburn Events Only one study was identified that was conducted specifically to define the effects of reburn on forest structure. That research was conducted at the Wenatchee Forestry Sciences Laboratory and remains unpublished. The CTC project team was not able to obtain a copy of that research for this report. In summary, reburns following a stand replacement fire: 1) reduce the amounts of dead and down materials created by the previous fire event, 2) reduce the post-fire understory response, and 3) result in an increase in weedy (or invasive) species (J. Landsburg personal communication).
Other references indicate that reburns have additional effects on forest stands. Agee (1993) reported the loss of understory species following two fires in rapid succession. He suggested that the loss of species resulted from depletion of remnant plants and soil seed reserves. For example, in the grand fir series, if a stand of lodgepole pine, Douglas-fir, and grand fir has a second fire within 20 years of a stand replacement event, the stand will lose its pine component through mortality of the pine and the loss of the lodgepole pine seed source (Cattelino et al. 1979). Remaining On-Ground Wood Following a Reburn The CTC project team found no literature specific to snag- or log-loading following reburn of sites with a previous stand replacement fire. Extrapolating from existing literature, log biomass may be estimated or modeled for stands following reburn. Given that reburns are surface fires, these events are unlikely to cause significant damage to standing snags. Therefore, only the consumption of log biomass by the reburn need be considered. Of primary concern are the small diameter logs currently on the ground and the small diameter snags that will become logs prior to the reburn event. Conversion of small snags to logs is anticipated to be more dependent upon decay than reburn effects. Large logs are anticipated to be more resistant to surface fires than small diameter logs during the interval between the first fire and the reburn. Information is available on snag fall down rates by species and stem size (Morrison and Raphael 1993, Everett et al. 1999, Harrod et al. 2000). The number or volume of small diameter (less than 23 cm dbh) snags that will fall within the median fire frequency interval for the site can be estimated. Adding current small logs to small diameter snags that will become logs prior to fire provides an estimate of potential reburn effects on the dead and down component of the stand.
If reburns are surface fires and fuel moisture is higher in riparian areas than upslope, discontinuous fires within the riparian areas are anticipated. Based on this assumption, it is feasible that riparian areas could support more logs than in more xeric upland forest sites. However, no information was available to support this assumption.
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Question 14
How are disease and insect infestations affected by stand density (by stand type)? How do current disease and insect infestation rates compare with historical rates? Did this vary between upland and ecological riparian communities? Response Availability of Information A wealth of information is available on the inherent insect and disease disturbance regimes associated with each Eastern Washington forest series. In some cases, information is specific to stand development stages for PAGs. Little information is available on historical disease and infestation rates in Eastern Washington forests. Estimated rates are largely inferred from information on historic stand characteristics. There appears to be very little information on the how pathogen and insect disturbance regimes may vary between riparian and upland forests. Contacts with professionals in the field revealed no additional published information on this subject (C. Schmitt personal communication, D. Scott personal communication). Effect of Stand Density on Disease and Insect Infestations Question 11 includes a discussion of the probability for increased disease, insect, and drought disturbances with increasing stand density. Disease and insect infestations are related to stand density, but species resistance increases with improved site quality. Successional stages in stand development may increase the abundance and continuity of host species and create favorable insect habitat (Hessburg et al. 1999). Associated with this increased opportunity for insect outbreak is the associated decline in individual tree and forest stand capability to resist attack because of tree density induced water or nutrient stress (Stoszek 1988). For example, Swetnam et al. (1995) demonstrated that spruce budworm outbreaks have been a part of Eastern Washington forest ecology for centuries, but now those outbreaks are more frequent and severe.
Heavily stocked stands where all growing space is occupied have less buffering capacity to withstand drought impacts than more open stands where all resources are not being currently utilized. Joyce et al. (2001) stated that “Forests tend to grow to the maximum leaf area that uses nearly all available growing-season soil water.” Consequently, a low precipitation year can create stress within forest stands. Low precipitation years have been associated with insect outbreaks (Thompson and Shrimpton 1983) and may increase the risk of insect, pathogen, and fire disturbance in stands (McCullough et al. 1998). It may be inferred that competition for water within dense stands, even under more moderate precipitation conditions, may simulate drought stress thus increasing the risk of pathogen and insect infestation.
Today, the ten-fold increase in basal area of the Douglas-fir understory produces an evident stress on ponderosa pine, western larch, and Douglas-fir. Foliage of both ponderosa pine and western larch crowns are noticeably thin and sparse. The Douglas-fir understory is heavily
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infected with dwarf mistletoe and radial growth is very slow. Some post-1919 understory Douglas-fir and western larch have advanced bole rot. Average radial growth in the last 20 years on ponderosa pine averaged 0.4 inches. All of these symptoms indicate severe growth stress related to overstocking (Arno 1997).
General trends have been for increased impacts from insects and pathogens as the amount of biomass cycled by fires has declined through fire suppression (Hessburg et al. 1994, Hessburg et al.1999). Landscape level assessments (e.g., the Eastside Forest Health Assessment and the Columbia River Basin Assessment) have shown that differences in historical and current insect and pathogen levels are sub-watershed specific (Lehmkuhl et al. 1994, Hessburg et al 1999). Portions of a watershed or ERU may have elevated insect pests while other portions of the watershed have seen the pest hazard decline. When a portion of a watershed is harvested or burned, one set of insects and pathogens may decline while another set increases.
Specific insect species that benefit from increasing tree density include:
• Western pine-shoot borer Infestation rates of western pine-shoot borer in ponderosa pine and lodgepole pine were found to be positively related to stand density (basal area) and growth increments, but negatively related to elevation (Stoszek 1988). Low soil moisture holding capacity and low nutrient availability are associated with increased infestation levels. • Douglas-fir tussock moth Outbreaks of Douglas-fir tussock moth in Douglas-fir and true firs are associated with drought conditions (Brookes et al. 1978 in Stoszek 1988). In the Clearwater National Forest in Idaho, defoliation from Douglas-fir tussock moth increased with elevation, stand age, and stocking levels within a site productivity class. Defoliation increased as the proportion of grand fir in the stand increased and the soil moisture holding capacity of the soil declined. • Western spruce budworm Defoliation of western spruce budworm on Douglas-fir, Engelmann spruce, and western larch was heaviest in fast-growing (pole-size) stands in early successional development and declined with increasing stand age (Stoszek 1988). Infestation rates increased with stand density. Disease and Insect Infestations Relative to Stand Type High elevation forests comprised of subalpine fir or Engelmann spruce have fewer pathogen or insect pests than other forest series. Excluding dwarf mistletoe, western larch is probably the most pathogen and insect pest free tree species. Western hemlock and red cedar are impacted by pathogens. Lodgepole pine has moderate hazard to both pathogens and insects, and grand fir, Douglas-fir, and ponderosa pine forests have major insect pests. Tree ring data suggest that insect outbreaks were present in historical forests, but they were less frequent and of less severity. RIPARIAN DISTURBANCE REGIMES IN EASTERN WASHINGTON Concurrent Technologies Corporation - 65 -
Severe insect outbreaks have occurred in riparian stands (e.g., spruce beetle on the northern portion of the Wallowa-Whitman National Forest and Douglas-fir beetle in old-growth riparian stands following the western spruce budworm outbreak in Northeast Oregon from 1980 to1993) (D. Scott, personal communication). Available data did not indicate whether these outbreaks in riparian areas are significantly more severe or occur more frequently than in upslope areas.
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Question 15
Do climax forests have catastrophic collapse when left undisturbed? Does this vary between upland and ecological riparian communities? Response Catastrophic Collapse of Climax Forests All forest stands pass through stages of initiation, development, and eventual collapse or destruction. In the progression from initiation of a stand to old growth status, the stand passes through several varied disturbance events that can partially or completely reinitiate stand development (Everett and Baumgartner 1997). Studying the eastside of the Cascades in Eastern Washington, Camp et al. (1996) found that only 10 to 16 percent of forest stands in pristine forests of the Swauk Late Successional Reserve were actually late successional old growth. Approximately 88 percent of the landscape had been subjected to at least partial stand disturbance. Natural disturbances rarely kill all structural elements from the preceding stands (Franklin et al. 2002). Even when multiple or extreme disturbances occur, some organisms often survive, including sexually mature trees (Franklin et al. 1995). Trees are sometimes killed by natural disturbances, but most disturbances remove or consume only a part of the killed trees and, in the case of windstorm, little of the organic matter (Franklin et al. 2002). Upland Climax Forests As previously stated (Question 2), current late-successional forests with higher densities in Eastern Oregon and Washington have the same insect and pathogen compliment as the traditional old forests, with increased magnitude, severity, and duration of outbreaks (Everett et al. 1994, Hessburg et al. 1993). A mosaic of younger forest types with a greater potential for wildfire surrounds old forest remnants (Agee 1993, Everett et al. 1994). Lynch and Swetnam (1992) found that western spruce budworm did not directly threaten old growth stands per se, but contributed greatly to fuel loading and to fire risk and hazard. If budworm outbreaks are more severe in the surrounding matrix due to fire exclusion and subsequent dominance by multi-storied stands of shade tolerant species, then old growth is threatened by proximity alone.
Old-growth conifer forests frequently are considered vulnerable to catastrophic fire, due to the large amounts of surface fuel and abundant ladder fuels (Heinselman 1981). Older forests in the northern Rockies, particularly those in transition from lodgepole pine to spruce and fir, are the most susceptible to wildfire (Perry 1988). In contrast, Western Washington old-growth areas appear to be less vulnerable than younger forests due to the horizontal discontinuity of fuels produced by patchiness in the crown layer. Rust (1990) discovered that susceptibility to windfall is enhanced by root rot disease in old-growth grand fir and Douglas-fir. Mortality in grand fir can also be the result of insect or fungal attack after wounding by fire.
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Much of tree death is considered episodic and erratic. Catastrophic destruction of stands represents the extreme form of episodic mortality where rates are greater than background for a cohort of trees. Episodic mortality rates vary with successional stage, tree species, and forest type, with some episodes occurring predictably, while others (e.g., volcanism and unusual climatic events) occurring by chance. Some of these episodes are related to successional stage (e.g., bark beetle attacks). Forest stands may develop beyond the long- term carrying capacity of the site during favorable periods, and have to respond to stress during unfavorable climatic periods (Franklin et al. 1987).
Although the death of mature trees may sometimes be abrupt, mortality is more often a complex and gradual process with multiple contributing agents. The exception is volcanism, an abiotic, allogenic, and extrinsic disturbance that is too random in its timing and impact to have much of an evolutionary effect, but produces a catastrophic collapse. Franklin et al. (1985) studied plant community dynamics at Mount Saint Helens and showed that the survival of organisms and the rate and composition of post-eruptive forest recovery were season-dependent. Franklin (1988, 1993) pointed out that in the case of Mount Saint Helens, the catastrophic disturbance to the uplands lead to creation of significant biological legacies in associated riparian and aquatic systems. Specifically, streams received major inputs of COD within areas of blown-down forest.
Another exception to the gradual mortality rule might be global climate change. Under global warming scenarios, as temperatures increase, the fertilizing effect of increased carbon dioxide concentrations is overwhelmed by exponential increases in evapotranspiration, reductions in precipitation, or potentially both. Reduced precipitation could set up a threshold response that shifts the processes from increased productivity to a rapid, drought- induced mortality (Aber et al. 2001). These changes could induce catastrophic and more frequent fires (Dale et al. 2000).
In the Pacific Northwest, mortality rates in mature and old-growth stands are not evenly distributed spatially. Generally, mortality is greater in habitats of high productivity than low productivity. A regional gradient exists where Sitka spruce-western hemlock is more susceptible than Douglas-fir, which, in turn, has greater productivity that ponderosa pine. Mortality from windthrow, wildfire, and fluvial patterns has strong spatial patterns. During maturation, mortality shifts from competitive to non-competitive. In later stages of maturity, insects, disease, and wind become more important causes of mortality (Franklin et al. 2002). Falling trees or snags do important mechanical work by often killing other trees or other organisms. Greater than 15 percent of tree death in mature and old-growth Douglas-fir stands in the Pacific Northwest consists of trees felled, broken, or crushed by falling trees (Franklin et al. 1987).
Inherent declines in vigor and growth reduce the ability of a tree to resist agents of mortality, and these patterns can be quite species-specific. Tree genera vary with respect to lifespan – some survive for millennia (e.g., Cupressaceae and Taxodiaceae). Some live longer when site conditions are harsh (e.g., bristlecone pine in the White Mountains of California live in excess of 3,000 years). Manion (1981) produced a mortality spiral for Douglas-fir where healthy tree are suppressed by larger trees. The tree is predisposed to attack by defoliators,
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weakened, and then becomes attractive to bark beetles. Bark beetles then infect the tree with blue stain fungus that blocks the transpiration stream causing desiccation of the leaves. Riparian Climax Forests Are climax forests possible in riparian ecosystems? The argument is that plant communities progress along successional pathways, but are continually adapting to changes in climate and natural disturbance, and, therefore, never truly reach an end point in succession. This argument has particular relevance to highly dynamic environments of the riparian ecosystem where hydrologic and geomorphic influences provide for an ever-changing environment.
Without disturbance, and in the absence of a nearby seed source for shade-tolerant trees, the riparian plant community might disappear over time. Hibbs and Bower (2001) and Nierenberg and Hibbs (2000) studied 150-year-old unlogged, unmanaged streams in Oregon’s Coast Range and found that, when the current stand was alder or Douglas-fir, the long-term future of many of these riparian areas is a relatively treeless condition. This is perhaps not catastrophic, but is a major shift in the overstory dominants nonetheless.
Flooding and its associated events such as sedimentation, bank scour, landslides, and debris torrents dominate riparian disturbances. These processes are intimately linked to the formation and maintenance of riparian systems. Channel formation begins with water accumulation, overland flow due to localized saturated areas, and a break in slope (Montgomery and Dietrich 1994). These processes do not disappear when late-successional plant communities dominate the riparian system. Water continues to flow downhill with the ability to do work on the landscape. Even in bedrock controlled systems, clear water is sediment hungry and has the capacity or competence to move a certain amount of bedload. Given a heavy snow year, warm rain on a wet snowpack, the appropriate geology, and overloading of a steep slope with moisture, conditions exist for a debris slide that turns into a debris torrent upon entering the stream channel (Dale et al. 2000, Johnson et al. 2000). A debris torrent has the potential to eliminate late-successional riparian vegetation with a single event (Johnson et al. 2000, Nakamura et al. 2000).
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Question 16
Where does the basal area, as required in the new forest practices rules, fall within the range of natural variability for historic stands (both upland and ecological riparian communities)? Response Availability of Scientific Information The absence of a significant information base on historical basal area and tree density by plant association limited the CTC project team’s ability to address this question. Additional information on historical basal area and tree density is needed before this question can be answered with confidence. Using information that was available, the following conclusions were drawn. Basal Area Requirements Relative to Natural Variability in Stands The F&FR minimum basal area requirement of 60 square feet per acre is high compared to historical values (10.3 to 22.3 square feet per acre basal area) for dry Eastern Washington Douglas-fir/ponderosa pine stands (Harrod et al. 1999). The F&FR high basal area group requirement of 50 trees per acre appears to be at the upper end of the range of historical tree data (Harrod et al. 1999). There does not appear to be any corroborating information for the F&FR tree density standard for the low basal area/high tree density group.
In the mixed conifer habitat type, the F&FR minimum basal area requirements for low, medium, and high productivity sites fall within the range of historical (1899) basal area values for Douglas-fir on the east slope of the Cascades (Ohlson et al. 2001 unpublished research). It appears that the 120 tree per acre target for the RMZ inner zone of low basal area/high density stands may be too high in some plant associations. Historical (100 years BP) tree density estimates for dry grand fir/Douglas-fir indicate that there may not have been 50 trees with greater than 13 cm dbh on many of these sites (Everett et al. 1996).
Historical estimates of basal area in riparian forests for western hemlock, mountain hemlock, western red cedar, grand fir and Douglas-fir would appear to exceed the minimum F&FR basal area requirements for the highest site potential stands. Lodgepole pine basal area would exceed the requirements for low and medium site index sites. However, the minimum F&FR basal area requirements for high elevation forests of 285 square feet per acre exceed the values found by Kovalchik (in press). The F&FR guides may not be in the range of historic conditions if the “pristine” sites used in Kovalchik’s classification serve as valid surrogates for historical conditions.
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Question 17
Where do the current timber habitat types defined in F&FR lie within the current and historical spatial and temporal variability of riparian communities of Eastern Washington? Response Spatial Distribution of Riparian Communities Kovalchik (in press) provides an assessment of the riparian plant communities. Using the community compositions provided by Kovalchik, the F&FR elevation zones, and forest habitat types (ponderosa pine, mixed conifer, and high elevation), a list of current riparian associations in each of the categories is presented.
Western Red Cedar Series (THPL)
Two western red cedar associations (Thuja plicata/Oplopanax and Thuja plicata/Athyrium filix-femina) are common, distinctive meso-riparian types occurring at moderately low to moderate elevations (plot ranges for all associations – 2,400 to 4,250 feet elevation) within mesic valleys. Most are located on the Colville and Kettle Districts on the central and eastern parts of the Colville National Forest where they are at least of minor occurrence. These associations occur in V-shaped and U-shaped valleys, on wet streambanks, floodplains, and terraces. These two associations fall primarily into the mixed conifer habitat type (2,500 to 5,000 feet). Two other western red cedar associations (Thuja plicata/Aralia nudiculis and Thuja plicata/Clintonia uniflora) reflect the drier sites and lower elevation zones of the western red cedar series (THPL). Elevations range from 2,200 to 4,000 feet with Thuja plicata/Aralia nudiculis found in wide U-shaped valleys and Thuja plicata/Clintonia uniflora found in narrow, V-shaped valleys. Both associations occur on stream terraces and the margins of basins and represent xero-riparian conditions. These two associations also fit into the mixed conifer habitat type (2,500 to 5,000 feet) with some overlap into the ponderosa pine habitat type (below 2,500 feet).
Engelmann Spruce Series (PIEN)
This series contains four associations that are quite different. The Picea engelmanii/Carex scopularum v. prionophylla is abundant at moderate to subalpine elevations on the Okanogan and Colville National Forests. Plot elevations range from 4,400 to 7,200 feet in the Cascades. This association is prominent along the margins of large flat basins and narrow stringers of steep, subalpine streams. Valleys are both U- and V-shaped. This association would fit primarily into the upper elevation habitat type (above 5,000 feet) with some overlap into the mixed conifer habitat type (2,500 to 5,000 feet). The other three associations (PIEN/Equisetum spp., PIEN/Gymnocarpum dryopteris, and PIEN/Cornus canadensis) fit the mixed conifer habitat type (2,500 to 5,000 feet). These sites vary from the margins of wet basins, on the tops of banks, on moist floodplains and terraces, or adjacent to streams on
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dry floodplains. PIEN/Gymnocarpum dryopteris and PIEN/Cornus canadensis represent xero-riparian conditions and PIEN/Equisetum spp. is meso-riparian.
Subalpine Fir Series (ABLA2) All but two of the associations in the Subalpine Fir Series (ABLA2) are riparian areas in the subalpine zone (Abies lasiocarpa/Rhododendron albiflorum, ABLA2/Gymnocarpum dryopteris, ABLA2/Cornus canadensis and ABLA2/Trautvetteria carolinensis). These associations occur in both the Colville and Okanogan National Forests. They represent cold, moist bottoms in both U-and V-shaped valleys. Sites are on streambanks, floodplains, and terraces where they represent xero-riparian conditions. The other two associations (ABLA2/Arthirium filix-femina and ABLA2/Streptopus amplexifolus) are at more moderate elevations with plots elevations ranging from 3,160 to 5,300 feet. These two would conform to the F&FR mixed conifer habitat type (2,500 to 5,000 feet) with some overlap into the high elevation habitat type (above 5,000 feet). These latter two associations represent cold, moist valley bottoms and sub-irrigated sideslopes representing meso-riparian conditions.
Quaking Aspen Series (POTR) One association (Populus tremuloides/Cornus stolonifera) in this series is a minor type at moderate elevations in the Colville, Republic, and Tonasket districts of the Colville and Okanogan National Forests. This riparian association is found in low gradient basins in trough-shaped valleys. The association is seasonally flooded, but represents xero-riparian conditions.
Black Cottonwood Series (POTR2) Two associations of the black cottonwood series (POTR2) (Populu trichocarpa/Alnus incana, POTR2/Cornus stolonifera) exist in low to moderately low elevations through the Colville and Okanogan National Forests. Both are found in wide, U-shaped valleys on terraces of major streams and rivers and the margins of lakes and basins. Sites are often seasonally flooded, but represent xero-riparian conditions.
Other Series The other series represented by riparian plant associations in Eastern Washington are shrub and herbaceous, such as tall and short willow, Sitka/alder, other shrubs (e.g., red-osier dogwood), sedge, and herbaceous non-sedge. These series are not included because timber types represent less than 15 percent of these associations. Temporal Distribution of Riparian Communities A mid-scale, Interior Columbia Basin-wide analysis of changes in riparian vegetation from pre-settlement showed a general decline in shrublands in the riparian areas in more than half of the ERUs (Quigley and Arbelbide 1997). Shrublands shifted to forests and herbaceous communities through succession or disturbance. Forests (that include riparian species such as cottonwood, aspen, and willow), woodlands, and herbaceous riparian communities remained approximately the same. However, other, more widespread forest types mask cover types dominated by riparian trees. Riparian forest types declined in six of thirteen
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ERUs. Important decreases occurred in the headwaters of the Snake River and the Columbia Plateau. Riparian area integrity and extent along watercourses has been altered and fragmented throughout the Columbia Basin in response to forest conversion and streamside disturbance (Quigley and Arbelbide 1997). Unfortunately, broad-scale changes in vegetation patterns were not assessed for riparian terrestrial vegetation types. Because these types generally occurred in scattered, relatively small- to medium-sized patches, they tended to be underestimated as mapping resolution increased. Since the historical vegetation layer was developed at a coarser resolution than the current period vegetation layer, bias in the two mapping efforts might be different. Thus, changes in riparian vegetation types between historical and current period were not assessed completely (Quigley and Arbelbide 1997).
On the broad scale, riparian woodland did not decline substantially between historical and current periods. Fine- or mid-scale analysis, however, suggested that this woodland type declined substantially. This decline is attributed to agricultural development, urbanization, and invasion by exotic plant species. The elevational distribution did not change substantially. Since the historical period, the structure and composition of riparian woodlands have changed due to disturbance by livestock grazing, invasion of exotic plants, agriculture, and urban development.
Solid comparisons between historical and current periods may exist for certain habitat types (e.g., ponderosa pine) (Arno 1993). However, a comprehensive evaluation was not found. Indirectly, this information could be inferred from fire history and frequency studies, but until 1998, few researchers specifically focused on successional dynamics in riparian areas (rather than aquatic habitats).
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Section 5.0
Data Gaps and Recommendations
In the process of addressing the project questions, the CTC project team identified the following data gaps and associated recommendations. General Data Gap
The scientific basis for future forest management may need to incorporate a finer scale than forest habitat type (e.g., disturbance and patch dynamics). The scientific literature describing Eastern Washington disturbance regimes and forest vegetation is at the forest series or PAG level. Question-Specific Data Gaps
Question 1 Data Gap: Relatively few studies have examined the differences in fire, insect, or pathogen disturbances between riparian and upslope forests. There are no studies on differences in pathogen or insect disturbance regimes for riparian and adjacent upslope forests. The inherent disturbance regime for insects and pathogens is less well defined because of the absence of a permanent historical marker for pathogen disturbance.
Recommendation: Conduct focused research projects that develop information on insect and pathogen disturbance regimes and vegetation response between adjacent riparian and upslope forests.
Question 2 No data gap identified. RIPARIAN DISTURBANCE REGIMES IN EASTERN WASHINGTON Concurrent Technologies Corporation - 75 -
Question 3 Data Gap: Avoidance, resistance, and resilience concepts need to be defined at the finer scale of stand development stages and at the coarser scale of landscapes. Disturbance hazard is often related to stand structure, and the significance of that hazard is evaluated at the landscape scale.
Recommendation: Conduct focused research projects that develop information on a finer scale of stand development stages and at a coarser scale of landscapes.
Question 4 Data Gap: There is an inability to accurately determine the proportion of the landscape that is or was likely to be affected by landslide disturbance without field verification. A bias towards detecting a greater percentage of landslides and erosion volume in younger versus older forests using air photographs significantly influences landslide density and erosion calculations
Recommendation: Conduct focused field research projects that develop information on landslide disturbance in younger versus older forests.
Question 5 No data gap identified.
Questions 6 Data Gap: Scientific information on historical stand structure (greater than 100 years BP) in Eastern Washington is scarce. The greatest information gap is on historical stand characteristics within high elevation forest types (e.g., subalpine fir and Engelmann spruce). The use of “recent historical” (1940 aerial photographs) provides a glimpse of stand and landscape structure already significantly altered from pre-European settlement conditions. These altered 1940s conditions may not be supported by inherent disturbance regimes.
Recommendation: Consider the use of “reference stands” from vegetation classification work to get an improved idea of the array of “pristine” conditions that were present prior to European settlement. Historical stand characteristics should be defined for all stand development stages to provide for a more “complete” view of stand structures and, collectively, “historical landscapes” supported by inherent disturbance regimes. Also, needed is landscape-level historical information on the proportion of different stand structures that populated the landscape.
Question 7 No data gap identified.
Question 8 No data gap identified. RIPARIAN DISTURBANCE REGIMES IN EASTERN WASHINGTON Concurrent Technologies Corporation - 76 -
Question 9 Data Gap: There is little stand-level information on large tree regeneration following stand replacement fires.
Recommendation: Use information on stand successional processes and individual tree re- establishment rates to help identify the stand types (plant associations and associated tree species) that would produce large trees when disturbances are applied.
Question 10 Data Gap: There is no information on “typical” survival rates following a stand replacement or understory fire.
Recommendation: The current mortality prediction models (e.g., FIRESUM) appear to accurately estimate mortality for specific areas and burn conditions. Use such models to estimate stand response to different fire intensities.
Question 11 Data Gap: There is no literature specific to the influences of drought and pest thinning in dense riparian forest stands in Eastern Washington.
Recommendation: In the absence of such information, data on silvicultural thinning practices and their effects may be used to develop an active management approach that reduces riparian forest health issues prior to the occurrence of catastrophic fire events.
Question 12 No data gap identified.
Question 13 Data Gaps: Three data gaps related to reburn following stand replacing fires were identified. No or limited data exists on the following:
• Across all series, the proportion of stand replacement fire areas that reburn prior to tree establishment. • The snag or log loading following a reburn of sites with a previous stand replacement fire. • A comparison of reburns upslope and adjacent to riparian forests.
Recommendation: Conduct research on the proportion of stand replacement fire areas that reburn and how such reburns affect riparian and upslope areas. Such information would be instructive if managers choose to re-introduce fires into Eastern Washington.
Question 14
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No data gap identified.
Question 15 No data gap identified.
Questions 16 See question 6.
Question 17 Data Gap: There is a lack of solid, comprehensive comparisons between historical and current forest structure, composition, and distribution (for all forest stand types).
Recommendation: Use fire history and frequency studies to develop a more comprehensive comparison of historical versus current forest stand distributions in Eastern Washington.
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PART 2
WORKSHOP SUMMARIES and ANNOTATED BIBLIOGRAPHY
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Section 1.0 2Section.0 2Section.0 Workshop Summaries
Eastside Forest Dynamic Workshops
The CMER and the ERSAG (now CMER SAGE) sponsored two Eastside Forest Dynamic Workshops during the spring of 2001. One workshop was held in Spokane, Washington on February 22, 2001, and the other in Ellensburg, Washington on May 22, 2001. The purpose of the workshops was to provide ERSAG with information to support their efforts related to F&FR adaptive management issues, which include providing direction to CMER, developing research, and forming effectiveness-monitoring programs.
A brief summary of the workshops is presented here. This summary is based on workshop materials and a video provided to the CTC project team by Pete Peterson, Upper Columbia United Tribes (UCUT), via Domoni Glass, and electronic files provided by Domoni Glass and Sondra Collins, UCUT.
The CTC project team attempted to contact the four speakers from the Ellensburg workshop. While successful in contacting Jim Agee, Gardner Johnston, and Diana Olson to request additional materials for their presentations, no additional materials were made available. Attempts to contact Jeanette Smith to obtain information were unsuccessful.
The CTC project team was not provided with sufficient suitable material to compile graphs and tables from each presenter, as requested by DNR.
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Forest Dynamic Workshop in Spokane, February 22, 2001 Summary The Spokane workshop was held on February 22, 2001, between 9 a.m. and 4 p.m. at the Gonzaga University Foley Teleconference Center. Presentations made at the workshop are as follows:
Fire Frequency in Riparian Areas Presenters: Richard Schelhaas and Don Spubeck
Eastern Washington Riparian/Wetland Classification Presenter: Bud Kovalchik
Computer Programs to Simulate Forest Processes Presenters: Chad Oliver
Small Woody Debris Presenter: Charles Chesney Transcribed Text from Spokane Workshop, February 22, 2001 The ERSAG Forest Dynamic Workshop held in Spokane was transcribed. The transcribed text was provided to the CTC project team electronically in four Microsoft® Word files. The contents of those files are provided in Appendix B. Summary of Presentations Delivered at the Dynamic Forest Workshop in Spokane, February 22, 2001 “Fire Frequency in Riparian Areas” Presenters: Richard Schelhaas and Don Spubeck Topics of the presentation included landscape and historic fire regimes in ponderosa pine and Douglas-fir forest series and historic fire regimes of riparian areas in Douglas-fir, ponderosa pine, and red fir series. The presenters defined historic conditions as those that existed prior to 1900.
Information presented was based on historic forest regime projects conducted in Eastern Washington during the last ten years. Study sites were located in the Okanogan and Wenatchee National Forests and range from 10,000 to 40,000 acres in size. Study activities included dendrochronology techniques and were designed to identify the frequency, severity, and size of historic fires.
Study data were used to identify fire characteristics. Data indicated that historically, fires were frequent and of low intensity. Under current conditions, fires are infrequent, due to fire suppression, and of high intensity. Data also indicated that the behavior of historic fires was not affected by landscape aspect (e.g., fires burned across ridge tops and riparian areas and RIPARIAN DISTURBANCE REGIMES IN EASTERN WASHINGTON Concurrent Technologies Corporation - 82 -
there was no significant difference between north and south aspects). Forest conditions have been significantly altered during this century leading to increased understory growth, presence of shade-tolerant Douglas-fir, stand density, and insect infestations, notably spruce budworm. Data indicated that riparian zone fires tended to be more severe than upslope areas due to increased accumulation of fuel in gullies.
The presenters asserted that, “Continuity in disturbance between riparian and sideslope forest and the continuity in disturbance between opposing slope forests suggest that management should consider landscape units in their entirety rather than as riparian and sideslope isolates when implementing ecosystem and disturbance management.”
“Eastern Washington Riparian/Wetland Classification” Presenter: Bud Kovalchik The presentation focused on how a riparian or wetland classification may – through a hierarchical, geomorphic view of riparian and wetland zones – help managers better understand riparian and wetland zone functions and processes, estimate their status and potential, prescribe proper management direction, and focus salmon recovery efforts.
After briefing the audience on his background and publications, the presenter provided information on riparian and wetland classifications. The presenter discussed his methodology of classifying areas that includes examining the geomorphology, physiography (geology and climate), hydrology, and potential natural plant community or climax conditions of a location. Broad-scale classifications have an accuracy of approximately two- thirds (i.e., 30 percent error). The presenter discussed several specific locations and their classifications. Additional discussion topics included riparian buffers, large woody debris (LWD), channel morphology, timber harvesting, and stream functions and processes.
The presenter asserted that Eastern Washington timber habitat types should not be based on coarse-scale concepts such as broad elevation bands and timber habitat types. A geomorphic-based/vegetation classification may be used at different scales to stratify the landscape to develop effective, reality-based management strategies for salmon habitat restoration in riparian/wetland zones.
“Computer Programs to Simulate Forest Processes” Presenters: Chad Oliver and Jason Cross This presentation focused on how information and knowledge can be integrated using science and technology to address forest management issues. Science-based concepts include forest dynamics, forest use, and demand for forest products. Forest management can focus at several levels (e.g. individual trees, stands, landscapes, and regions). These levels result in a hierarchy. The systems approach requires an understanding of the behavior of the hierarchy system. This approach relies on using best available science and completing sensitivity analyses and monitoring (i.e., continuous quality improvement).
Until recently, the predominant ecological paradigm was that the forest existed in a steady state, climax condition that could be managed through selective cutting and preservation of RIPARIAN DISTURBANCE REGIMES IN EASTERN WASHINGTON Concurrent Technologies Corporation - 83 -
large tracts to retain native species. It is now accepted that forests are very dynamic because of vegetation growth and disturbances. Additionally, present-day forests have multiple uses that require different ecological conditions. To attain these conditions, integrated management is needed. Computers may be used to evaluate forest growth, silvicultural operations, timber inventory, geography (GIS), financial analyses, habitat suitability indices, and riparian relationships. Changing forest structures and values can be projected and modeled over time.
The remainder of the presentation focused on how computer simulations may be used to facilitate integrated forest management. A brief demonstration of a computer model, called Landscape Management System, was presented. Simulations can be used to estimate the effect of stand management activities on forest and riparian functions and conditions, including habitat conditions needed to maintain water quality and fish habitat and slope stability. Simulation models have the potential to be very complex depending on what inputs and outputs are desired.
“Small Woody Debris” Presenter: Charles Chesney A long-term monitoring project is being conducted with the goal of improving forest management activities. The project includes monitoring activities at 18 sites, both managed and unmanaged. Data are collected at 5-year intervals or on event-triggered basis to determine how much riparian vegetation is needed for adequate wood input to the channel, how much functional in-channel wood is needed to retain sediment, and to develop recommendations for creating conditions for a self-sustaining wood supply.
Small woody debris is defined as a range of woody debris with a minimum size of 1-foot in length and 1-inch mid-point diameter and a maximum size of 6-feet in length and 4-inch mid-point diameter. The presenter asserted that small woody debris plays just as significant a role in stream habitats as LWD.
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Dynamic Forest Workshop in Ellensburg, May 22, 2001 Summary The Ellensburg workshop was held on May 22, 2001, between 9:00 a.m. and 4:15 p.m. at Holmes Hall at the Holmes Community Center. Presentations made at the workshop are as follows:
Historical Riparian Conditions – What Do We Know, What Don’t We Know Presenter: Jim Agee
Historical Riparian Characteristics in the Blue Mountains Presenter: Diana Olson
Historical Shade Conditions in Eastern Washington Presenter: Gardner Johnston
Historical Wood Loads in North Eastern Cascade Streams Presenter: Jeanette Smith Summary of Presentations Delivered at the Dynamic Forest Workshop in Ellensburg, May 22, 2001 Historical Riparian Conditions – What Do We Know, What Don’t We Know Presenter: Jim Agee No record of Dr. Agee’s presentation was made available to the CTC project team. When contacted by email, Dr. Agee responded that no concurrent paper was prepared or requested for the meeting. No documentation for this presentation was made available.
Historical Riparian Characteristics in the Blue Mountains Presenter: Diana Olson No record of Diana Olson’s presentation was made available to the CTC project team. Subsequent efforts to contact her were unsuccessful. Since the title of her presentation matches the title of her Master of Science thesis, the abstract of the thesis is presented here:
Despite the ecological importance of fire in Pacific Northwest forests, its role in riparian forests is not well documented. This study reconstructed the historical occurrence of fire within riparian forests along different stream sizes within three different national forests in Oregon. Two study areas were located in mostly dry, low-severity fire regime forests in the Blue Mountains of northeastern Oregon (Dougout and Baker) and the third study area was located in more mesic, moderate-severity fire regime forests on the western slopes of the southern Oregon Cascades (Steamboat). Fire scar dates and tree establishment dates were determined from a total of 424 fire scarred tree
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wedges and 81 increment cores taken from 67 riparian and upslope plots. Based on the data from this study, fire was common historically in the riparian zones of all three study areas. Weibull median probability fire return intervals (WMPIs) for riparian forests in Dugout ranged between 13 and 14 years, and were only slightly longer than those for upslope forests (averaging one year longer). In Baker, differences between riparian and upslope forest WMPIs were greater, ranging between 13 and 36 years for riparian WMPIs, compared to 10 to 20 years for upslope WMPIs. However, further analyses suggested that forest type and slope aspect play a larger role than proximity to a stream when it came to differentiating fire regimes in this study area. For both Dugout and Baker it appeared that stream channels did not necessarily act as fire barriers during the more extensive years. Steamboat riparian WMPIs were somewhat longer (ranging from 35 to 39 years) than upslope WMPIs (ranging from 27 to 36), but these differences were not significant. Fires were probably more moderate in severity and likely patchy, considering the incidence of fires occurring only at a riparian plot or an upslope plot within a pair, but not at both. It is possible that fire return interval lengths were associated with aspect, but more sampling would need to be done to show this. Based on the results from this study, it is evident that: 1) restoring fire, or at least conducting fuel reduction treatments, will be necessary to protect riparian forests in comparable forest ecosystems, 2) forests should be managed according to forest type, not just by proximity to a stream, and 3) historical recruitment of large woody debris was likely small but continuous for low-severity fire regime riparian forests, with a relatively short residence time, and patchy and more pulsed for the more moderate-severity fire regime forests (Olson 2000).
Historical Shade Conditions in Eastern Washington Presenter: Gardner Johnston No record of Gardner Johnston’s presentation was made available to the CTC project team. When contacted, Gardner Johnston provided the CTC project team with a copy of his thesis, Riparian Canopy Cover in Northeastern Washington: Stream Temperature Response, Historical Reference Conditions, and Management Effects (2002). The abstract of the thesis is presented here:
Northeastern Washington riparian forests have undergone changes to species composition and structure as a result of land management. Changes to riparian forests are of interest due to stream and forest health concerns. Timber harvest can reduce canopy cover and increase stream temperatures, while fire suppression, combined with the effects of past harvest, can alter stand conditions, with associated insect, disease, and wildfire risks. Riparian timber harvests aimed at reducing forest health risks may be in conflict with current policies that limit harvest to protect aquatic resources. Understanding how timber harvest affects stream temperature, how riparian management alters stand conditions, and how riparian canopy cover was historically distributed across the landscape will aid in the selection of appropriate RIPARIAN DISTURBANCE REGIMES IN EASTERN WASHINGTON Concurrent Technologies Corporation - 86 -
riparian treatments. The first objective, to evaluate relationships between stream temperature and timber harvest in the study area, was accomplished by comparing stream temperatures in adjacent harvested / non-harvested reach pairs, and by regressing canopy cover against stream temperature. Paired- reach results were not statistically significant but linear regression showed a statistically significant increase of maximum temperature with a decrease in canopy cover. The second objective, to evaluate historical to current changes in riparian forest species composition and structure, was accomplished by comparing riparian stand conditions recorded in historical and current land surveys. Results showed a decrease in fire-adapted species and decreased tree size. The third objective, to investigate the historical distribution of riparian canopy cover on northeastern Washington streams, was accomplished by measuring cover using historical (1930s and 1940s) aerial photography. Cover levels were compared to several landscape variables and to four unique biophysical settings. Basin area, valley bottom width, surficial geology, and flow direction exhibited the best relations with canopy cover; elevation was a poor predictor of cover. The final objective, to evaluate the influence of management on riparian cover, was assessed using canopy cover and land management type measured from historical and current (1994 and 2000) aerial photographs. Reaches impacted by recent (within past 10 years) timber harvest showed a decrease in cover levels between the historical and current periods. Reaches without active management (only fire suppression) had greater cover levels than in the historical condition. Results indicated that for mature, fire-suppressed stands, if no greater than approximately 15% canopy cover was removed during timber harvest, then cover levels were likely to be retained near historical levels (Johnston 2002).
Historical Wood Loads in North Eastern Cascade Streams Presenter: Jeanette Smith This presentation focused on LWD. ICBEMP and U.S. Forest Service (USFS) standards for LWD vary. The ICBEMP standard is 20 pieces per mile. The USFS standard for the Okanogan National Forest is 100 pieces per mile. Both systems define LWD as woody debris that is greater than 35 feet in length and greater than 20 inches in diameter. Neither standard is considered representative of reference conditions in the Northeastern Cascades.
Information was presented on a study conducted for the Chewuch River. Aerial photograph analysis shows that, over time, LWD accumulated at the same sites, indicating that channel and valley geomorphology may be influencing factors. Data indicated that LWD jams recovered over time. Patterns of LWD distribution indicated that LWD appears in accumulations that, without further disturbance, continue to accumulate material and individual pieces at greater frequencies.
Differences in forest type may be as important as channel and valley geomorphology, large river processes, disturbance regimes, and management, when evaluating reference conditions. Dry ponderosa pine had lower recruitment rates, increased root strength, slower growth to maturity, and longer recovery time than higher elevation, wetter spruce/lodgepole RIPARIAN DISTURBANCE REGIMES IN EASTERN WASHINGTON Concurrent Technologies Corporation - 87 -
pine. Study results suggest that LWD parameters should be stratified by sub-regions that reflect differences in LWD recruitment and depositional processes and channel geomorphologic parameters such as gradient and confinement.
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Section 2.0
Annotated Bibliography
Background
This portion of this report presents information requested in the Scope of Work Task A: “Annotated Bibliography.” An annotated bibliography related to the topics described in Task B: “Summarize Available Information,” was assembled from literature searches and submittals obtained from scientists and resource specialists (see Appendix A). Best efforts were made to identify pertinent reference materials for this annotated bibliography. Task A also involved gathering, summarizing, and documenting two Forest Dynamics Workshops sponsored by Eastside Riparian Scientific Advisory Group (ERSAG) (now CMER SAGE) (see Workshop Summaries).
To identify appropriate references, the CTC project team developed an assessment methodology to screen references. To complete this task, the CTC project team identified topic areas within the project questions, determined relationships between topic areas, and selected keywords to facilitate literature searches. The CTC project team screened references by geographic location, relevance to topic areas, and type of document (either summary document or single study). Categorized references are presented in the following order:
• Highly Relevant Summary Documents: Includes summary documents (i.e., references that refer to more than a single study) that were deemed by the CTC project team to be highly relevant to this project because of topic areas covered and geographic location of studies included in the document. References included in this category addressed at least one project topic area directly and were geographically focused on Eastern Washington or other, very similar landscape, such as Eastern Oregon. • Highly Relevant Studies: Includes single study reports that were deemed by the CTC project team to be highly relevant to this project because of topic areas covered and geographic location of the study. Studies included in this category addressed at least one project topic area directly and were geographically focused on Eastern Washington or other, very similar landscape, such as Eastern Oregon.
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• Other Highly Relevant Reference: Includes references that were deemed by the CTC project team to be highly relevant to this project because of topic areas covered and geographic focus of the study. No abstracts or summaries were available. • Relevant Summary Documents: Includes summary documents that were deemed by the CTC project team to be relevant to this project because of topic areas covered or geographic focus of studies included in the document. References included in this category addressed at least one project topic area, directly or indirectly, or were geographically focused on Eastern Washington or other, very similar landscape, such as Eastern Oregon. • Relevant Studies: Includes single study reports that were deemed by the CTC project team to be relevant to this project because of topic areas covered or geographic focus of the study. Studies included in this category addressed at least one project topic area, directly or indirectly, or were geographically focused on Eastern Washington or other, very similar landscape, such as Eastern Oregon. • Supporting Summary Documents: Includes summary documents that were deemed by the CTC project team to be supportive to this project because of topic areas covered or geographic focus of studies included in the document. References included in this category addressed at least one project topic area to a limited extent, but may not be related geographically to the project area. • Supporting Studies: Includes single study reports that were deemed by the CTC project team to be supportive to this project because of topic areas covered or geographic focus of studies included in the document. References included in this category addressed at least one project topic area to a limited extent, but may not be related geographically to the project area. • General References: Includes documents that were deemed by the CTC project team to be general references for this project because of topic areas covered or geographic focus of studies included in the document. References included in this category may not address any of the project topic areas directly, but do provide useful background information. • Other Works Cited: Includes a list of other references cited. Complete citations were unavailable. No attempt to categorize references by disturbance type, duration, or other metric was made. Upon review of the extensive collection of materials, and considering the extent of subject matter cross-over between documents, classification by these additional categories within the available project funding, was not possible. The CTC project team focused the available project resources on summarizing the identified information.
For each citation (except where noted), there is an annotation. There are two types of annotations: abstracts and summaries. An abstract is a direct quote from the cited reference. An abstract may be the actual abstract presented by the author(s) or may be an excerpt from the text of the document that summarizes the citation. A summary is not a direct quote from the citation. Each summary was written by CTC project team and briefly outlines the topics and conclusions of the citations.
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Highly Relevant Summary Documents
Agee, J. K. 1991. Fire History of Douglas-Fir Forests in the Pacific Northwest. In Wildlife and Vegetation of Unmanaged Douglas-Fir Forests, Edited by Ruggiero, L. F. U.S. Department of Agriculture Forest Service.
Abstract: The fire history of Pacific Northwest Douglas-fir forests is varied and complex because Douglas-fir exists in a variety of forest types over a wide range of environments. Douglas-fir has been dominant over this region because of disturbance by fire and the species' adaptations to fire. Human-caused fires have been locally important, but lightning appears to be most significant in explaining fire history. A lightning fire model based on climate suggests a strong north-sough gradient in lightning ignitions. The western Olympic Mountains have a very low probability of ignition by lightning; the southern Washington Cascades have twice as much; the western Oregon Cascades have another 60 percent more; and the Siskiyou Mountains have twice, again as much. Our knowledge of fire return intervals based on forest age-class data shows a parallel history, ranging from fire return intervals over several centuries in the Olympics to several decades in the Siskiyous. Most Olympic forests have developed as first-generation stands after historic fires; Siskiyou forests are usually multi-aged stands that have experienced several fires. Almost all of the old- growth Douglas-fir resource is a product of fire: it not only has created and maintained such stands but has destroyed them as well. In the short term, management strategies to perpetuate old growth can focus on protection against fire. In the long term, we will be forced to recognize a more dynamic management strategy, sensitive not only to historic fire regimes, but also to those expected with future climatic change.
_____. 1993. Fire Ecology of Pacific Northwest Forests. Washington, DC: Island Press.
Abstract: This book began as a source book for natural area managers interested in restoring or maintaining fire in the natural areas of the Pacific Northwest. It grew to encompass a broader charge: to provide a natural baseline that wildland managers, or those interested in wildland management, could use in understanding the effects of natural or altered fire regimes in the western United States. This ecological perspective about fire is not a prescriptive guide, since prescriptions must include management objectives. The management emphasis is on the role of fire in natural areas, but such information is also useful in fire applications for other management purposes.
The structure of most virgin forests in the American West today reflects a past disturbance history that includes fire. Although media reports of the 1988 Yellowstone fires treated the scene as an ecological catastrophe, these forests were born of fire in the 1700s and are now being reborn in the 1990s. Knowledge of the natural and often inevitable disturbances likely to affect forests, inlcuding fire, is essential to any forest management plan, whether the objective is timber production, wildlife conservation, or wilderness management. Crating desirable forest stand RIPARIAN DISTURBANCE REGIMES IN EASTERN WASHINGTON Concurrent Technologies Corporation - 92 -
structures in the future for these objectives may not require simulation of past fire activity. Such effort, however, will be successful only if we understand the processes responsible for desirable structures we see today before undertaking future stand manipulation.
The geographic coverage of this volume is applicable to much of the western United States, although the focus is on forest types found in Oregon, northern California, and Washington. Where those types occur in adjacent regions, information on them has been included. I chose to exclude those forest types endemic only to other areas of the West, such as giant sequoia forests. Non-forest vegetation is included where it is transitional to forest, as in oak and juniper woodlands or subalpine environments.
_____. 1994. Fire and Weather Disturbances in Terrestrial Ecosystems of the Eastern Cascades. PNW-GTR-320. Portland, OR: U.S. Department of Agriculture Forest Service.
Abstract: Fire has been an important ecological process in eastside Cascade ecosystems for millennia. Fire regimes ranged from low severity to high severity, and historic fire return intervals ranged from less than a decade to greater than 300 years. Fire history and effects are described for grassland and shrubland ecosystems, and the range of forested communities by plant series: Ponderosa Pine, Douglas- fir/White fir/Grand fir, Lodgepole pine, Western hemlock/Western redcedar, and subalpine fir/Mountain hemlock. The riparian zones within these communities may be more or less impacted by fire. The effects of extreme weather events, including unusual temperature, wind, or moisture have generally had less significant impact than fire. Management practices, including fire suppression, timber harvesting, and livestock grazing, have altered historical fire regimes, in some cases irreversibly. The management issues for the 1990s include both management and research issues, at a grand scale with which we have little experience. Ecosystem and adaptive management principles will have to be applied.
Belt, G. H., O’Laughlin, J. and Merrill, T. 1992. Design of Forest Riparian Buffer Strips for the Protection of Water Quality: Analysis of Scientific Literature. Report No. 8. Moscow, ID: Idaho Forest, Wildlife and Range Policy Analysis Group.
Abstract: The primary purpose of this report is to identify, evaluate, and synthesize research-based information relating riparian buffer strips to forest practices, water quality, and fish habitat. Objectives for this report are stated as five focus questions around which the report is organized: [1] What is a buffer strip? [2] How do forest practices within buffer strips affect water quality and fish habitat? [3] How effective are buffer strips in reducing impacts of forest practices? [4] What are the issues in buffer strip desgin? [5] What models are available for use in buffer strip design?
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Bilby, R. E. and Wasserman, L. J. n.d. Forest Practices and Riparian Management in Washington State: Data Based Regulation Development. In Unknown.
Abstract: In the past, forest practice regulations for riparian zones in Washington have been based primarily on political, rather than scientific, considerations. In 1986 a new process, called Timber, Fish and Wildlife, attempted to formulate regulations based on technical data. Separate regulations were devised for eastern and western Washington due to the difference between the two regions in vegetation, climate, and timber management strategies. In western Washington, where clear-cutting is the predominant harvest method, regulations were based on existing data on large organic debris (LOD) loading in channels coupled with simulation models of stand dynamics. The regulations were designed to provide for the maintenance of LOD at the levels observed in streams in old-growth timber. Data for Eastern Washington riparian zones were collected specifically for the purpose of designing new regulations. Uneven-aged management is the most common silvicultural technique practiced in this area. Information was collected on riparian stand characteristics and LOD size and frequency in streams. Regulations were designed to maintain LOD levels observed in unmanaged stands and were based on relationships between stand density and LOD frequency. Wildlife needs were addressed by providing sufficient numbers of larger trees to generate snags, provide desired levels of canopy cover and maintain a multi-storied canopy.
Bull, E. L., Aubry, K. B. and Wales, B. C. 2001. Effects of Disturbance on Forest Carnivores of Conservation Concern. Northwest Science 75: 180-184.
Abstract: The effects on forest carnivores of forest insects, tree diseases, wildfire, and management strategies designed to improve forest health (e.g., thinning, salvage operations, prescribed burns, and road removal) are discussed. Forest carnivores of conservation concerns in eastern Oregon and Washington includes the Canada Lynx (Lynx canadensis), wolverine (Gulo gulo) and fisher (Martes pennanti). All three species depend to some degree on forest structures, stands, and landscapes created by insects, disease, and fire. Wildfire and insect outbreaks maintain a mosaic of structural stages across the landscape that are used by lynx. Thinning of dense lodgepole pine (Pinus contorta) stands that result largely from wildfire and insect outbreaks is detrimental to snowshoe hares (Lepus americanus), which are the primary prey of lynx. Fishers use large stands of mature forest and snags, hollow live trees, logs, stumps, witches-brooms, and other structures for rest and den sites Salvage harvesting, thinning, and conversion from predominantly fir stands to ponderosa pine (Pinus ponderosa) may adversely affect habitat conditions for fishers. Use of roads is perhaps most detrimental to wolverines because they are easily trapped and avoid humans.
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Campbell, S. and Liegel, L. 1996. Disturbance and Forest Health in Oregon and Washington. PNW-GTR-381. Portland, OR: U.S. Department of Agriculture Forest Service.
Abstract: The scope and intensity of disturbance by such agents as fire, insects, diseases, air pollution, and weather in Pacific Northwest forests suggests that the forest health has declined in recent years in many areas. The most significant disturbances and causes of tree mortality or decline in Oregon and Washington are presented and illustrated. We discuss the interrelations of disturbance with forest management actives and the effect on native trees and suggest some solutions for reducing the severity of disturbance. One chapter reports on a forest health monitoring pilot project.
Campbell, S., Ripley, K. and Snell, K. 1996. An Overview of Disturbance and Forest Health in Oregon and Washington. In Disturbance and Forest Health in Oregon and Washington, edited by Campbell, S., et al. Portland, OR: U.S. Department of Agriculture Forest Service.
Abstract: This report was written to help people understand the disturbances at work in the forests of Oregon and Washington, their significance, the underlying causes, and possible actions to improve forest health. Chapter 1 is devoted to some forest health topics that people in both states are concerned about: vegetation change, mortality, weather trends, exotic pests, and air pollution. We also include a section on forest health monitoring methods.
Covington, W.W., R.L. Everett, R. Steele, et al. 1994. Historical and anticipated changes in forest ecosystems of the inland west of the United States. Journal of Sustainable Forestry 2: 13-63.
Abstract: Euro-American settlement of the Inland West has altered forest and woodland landscapes, species composition, disturbance regimes, and resource conditions. Public concern over the loss of selected species and unique habitats (e.g., old-growth) has caused us to neglect the more pervasive problem of declining ecosystem health. Population explosion of trees, exotic weed species, insects, diseases, and humans are stressing natural systems. In particular, fire exclusion, grazing, and timber harvest have created anomalous ecosystem structures, landscape patterns, and disturbance regimes that are not consistent with the evolutionary history of the indigenous biota. Continuation of historical trends of climate change, modified atmospheric chemistry, tree density increases, and catastrophic disturbances seems certain. However, ecosystem management strategies including the initiation of management experiments can facilitate the adaptation of both social and ecological systems to these anticipated changes. A fairly narrow window of opportunity – perhaps 15-30 years – exists for land managers to implement ecological restoration treatments.
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Everett, R., R. Schellhaas, T. Anderson, et al. 1996. Restoration of ecosystem integrity and land use allocation objectives in altered watersheds. Watershed restoration management: Physical, chemical, and biological considerations (Proceedings, AWRA Annual Symposium). Herndon, VA: American Water Resources Association.
Abstract: Overstocked stands, resulting from a century of reduced fire effects and selective tree harvesting, are taxing the biological capacity and increasing the fires and insect hazard of the dry ponderosa pine forests of the Inland West. These dense, multi-canopy forests are not sustainable under the inherent high fire frequency-low severity fire regime characteristic of this forest type. The increasing disparity between current and inherent disturbance regimes and associated vegetation characteristics sets the stage for catastrophic disturbance events that can adversely impact the biological capacity of the ecosystem and our ability to restore vegetation characteristics required for emphasized uses within established land allocations. The restoration of the 1994 Tyee Burn in Eastern Washington is used as an example of how to plan for future forests that maintain biological capacity while meeting public expectations for vegetation characteristics that define a desired level of biological integrity within land use allocations. The restoration approach evaluates stand and landscape attributes required to reduce hazard for post-burn catastrophic events and to achieve emphasized uses for an array of land use allocations, integrates these hazard reduction and emphasized use attributes, and evaluates the composite forest attributes for sustainability under the inherent disturbance regimes for the area.
Everett, R., Hessburg, P., Lehmkuhl, J., et al. 1994. Old Forests in Dynamic Landscapes. Journal of Forestry 92(1): 22-25.
Abstract: Old-Forest abundances have been significantly reduced in most major conifer series and most geographic areas of eastern Oregon and Washington since presettlement times. Open, parklike, multicohort forests of ponderosa point (Pinus ponderosa) once covered extensive areas prior to `850 (Cowlin et al. 1942). The current late-successional and old ponderosa pine forest covers 2-8 percent of that originally occurring in eastern Oregon national forests (Scientific Society Panel 1993). New, younger, multilayered forests of dense Douglas-fir and grand fir (Abies grandis) have been created as a result of fire suppression and selective harvesting. Although these forests possess some old-forest attributes, they are more vulnerable to insects, pathogens, and strand-replacing fires (Caraher et al. 1992, Agee 1993, Hessburg et al. 1993, Mason and Wickman 1993).
Current anomalous landscapes and disturbance regimes need to be restored to a more sustainable state if old-forest remnants are to be conserved and old-forest networks created and maintained. Moreover, any plan to sustain old forests must first address the ecological sustainability of the landscapes of which they are a part. This article will describe old forests of eastern Oregon and Washington, contrasting historic (for this article, 1930-50) and current (1980-90) abundance and structure. It will also offer a philosophy for conserving old-forest patches and associated landscapes.
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Gast, W. R., Scott, D. W., Schmitt, C., et al. 1991. Blue Mountains Forest Health Report: New Perspectives in Forest Health. U.S. Department of Agriculture Forest Service.
Abstract: A report that provides the Umatilla, Malheur, and Wallowa-Whitman National Forests (Blue Mountain National Forests) with a preliminary framework upon which land managers can build appropriate strategies for restoring and maintaining the health of forest resources in Northeast Oregon and Southeast Washington. The report includes a discussion of the primary issues of forest health, analyses of existing conditions, and recommendations for future management.
Harvey, A. E., McDonald, G. I. and Jurgensen, M. F. 1992. Relationships Between Fire, Pathogens, and Long-Term Productivity in Northwestern Forests. In Fire in Pacific Northwest Ecosystems: Exploring Emerging Issues. Corvallis, OR: Oregon State University.
Summary: An introduction to the relationship between fire and disease in Northwestern Forests. The authors hypothesize that critical ecosystem functions of native pests likely amount to more than just agents for carbon and nutrient cycling – but they include a genetic screening component as well, and that this is an important additional dimension to pest management, particularly in inland forests.
Hessburg, P. F., Mitchell, R. G. and Filip, G. M. 1994. Historical and Current Roles of Insects and Pathogens in Eastern Oregon and Washington Forested Landscapes. PNW-GTR-327. Portland, OR: U.S. Department of Agriculture Forest Service.
Abstract: This paper examines by climax conifer series, historical and current roles of many important pathogens and insects of interior Northwest coniferous forests, and their unique response to changing successional conditions resulting from management.
Insects and pathogens of the subalpine fir and mountain hemlock series historically reduced inter-tree competition for site resources, and generated most of the coarse woody debris between fires. Severity of growth and mortality effects was proportional to the abundance of susceptible seral species such as Douglas-fir, grand- fir, and lodgepole pin within and adjacent to subalpine fir and mountain hemlock forests. Laminated root rot, a mortality factor, influenced successional status, fire intensity, and fire behavior. Insects and disease disturbances in present day western hemlock and western redcedar climax forests are much the same as those occurring historically, but increased scale of fire disturbance resulting from fire exclusion, has increased the scale of insect and pathogen disturbances associated with changing sussessional conditions.
Spectacular differences are apparent when comparing historical and current roles of pathogens and insects of the Douglas-fir and grand-fir series. Before the advent of fire control on public lands, late successional and climax forest stands were relatively scarce in comparison with current distribution. A century of fire protection has
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produced a steady shift away from parklike ponderosa pine and western larch forests toward denser late-successional fir forests. Harvesting of high-value seral overstories accelerated conversion to insect- and pathogen-susceptible late-successional forests. Douglas-fir and grand (white) fir are highly susceptible to root pathogens, bark beetles, defoliators, and dwarf mistletoe. Excluding fire from grand fir and Douglas- fir forests has perhaps been the single greatest detriment to diversity of eastside forests, and a primary factor in current susceptibility to major pathogens and insects.
Low intensity fires, once common to historical ponderosa pine climax forests, maintained low fuel loads, minimized fuel ladders, and spaced trees struggling to survive under severe moisture-limited growing conditions. The western pine beetle and mountain beetle thinned densely stocked areas missed by fire, and killed trees injured by wind and weather, or weakened by root disease, dwarf mistletoe, pandora moth, or advanced age. With fire control, overstocked conditions became widespread and bark beetles assumed the role of under burning to the elimination of trees in excess of site potential. Regeneration of historical lodgepole pine forests was predicated on mountain pine beetle outbreaks and subsequent stand replacing fore events. Today, with fire control, mountain pine beetle outbreaks affect larger areas, for longer periods, often with greater intensity than historical outbreaks.
Specific solution to elevated insect and disease disturbance in current forests is complicated by great variety in environmental and vegetal conditions where rehabilitation might be needed, and change in biological and physical potentials as a direct result of management. Still, much can be done. Stocking can be reduced where long-term carrying capacity is exceeded. The shift toward late-successional, fire intolerant, pathogen- and insect-susceptible forests can be reversed by developing a seral-dominated forest matrix. Management activates can promote landscape structure, composition, and pattern, consistent with historical disturbance regimes and land potentials.
Future research on forest pathogens and insects should address three primary subject areas; insect and pathogen population dynamics in managed and unmanaged forests; ecological roles and effects of native and introduced pathogens and insects; and, effects of natural disturbances and management practices on native insects, pathogens, and their natural enemies.
Hessburg, P. F., Smith, B. G., Kreiter, S. D., et al. 1999. Historical and Current Forest and Range Landscapes in the Interior Columbia River Basin and Portions of the Klamath and Great Basins: Part 1: Linking Vegetation Patterns and Landscape Vulnerability to Potential Insect and Pathogen Disturbances. PNW-GTR-458. Portland, OR: U.S. Department of Agriculture Forest Service.
Abstract: Management activities of the 20th century, especially fire exclusion, timber harvest, and domestic livestock grazing, have significantly modified vegetation spatial patterns of forests and ranges in the interior Columbia basin. Compositional patterns as well as patterns of living and dead structure have changed.
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Dramatic change in vital ecosystem processes such as fire, insect, and pathogen disturbances, succession, and plant and animal migration is linked to recent change in vegetation patterns. Recent change in vegetation patterns is also a primary reason for current low viability and threatened, endangered, or sensitive status of numerous native plant and animal species. Although well intentioned, 20th-century management practices have not accounted for the larger patterns of living and dead vegetation that enable forest ecosystems to function in perpetuity and maintain their structure and organization through time, or for the disturbances that create and maintain them. Knowledge of change in vegetation patterns enhances resource manager and public awareness of patterns that better correspond with current climate, site conditions, and native disturbance regimes, and improves understanding of conditions to which native terrestrial species have already adapted.
In this study, we characterized recent historical and current vegetation composition and structure of 337 randomly sampled subwatersheds (9,500 hectare average size), in 43 of 164 total subbasins (404,000 ha average size), selected by stratified random draw on all ownerships within the interior Columbia River basin and portions of the Klamath and Great Basins (collectively referred to as the basin). We compared landscape patterns, vegetation structure and composition, and landscape vulnerability to 21 major insect and pathogen disturbances of historical and current vegetation coverages. For each selected subwatershed, we constructed historical and current vegetation maps from interpretations of 1932-66 and 1981-93 aerial photos, respectively. Areas with homogeneous vegetation composition and structure were delineated as patches to a minimum size of 4 ha. We then attributed cover types (composition) structural classes (structure), and series-level potential vegetation types (site potential) to individual patches within subwatersheds by modeling procedures. We characterized change in vegetation spatial patterns by using an array of class and landscape pattern metrics and a spatial pattern analysis program. Finally, we translated change in vegetation patterns to change in landscape vulnerability to major forest pathogen and insect disturbances. Change analyses results were reported for province-scale ecological reporting units.
Forest and range ecosystems are significantly altered after their first century of active management, but there is reason for guarded optimism. Large areas remain relatively unchanged and intact, such as can be found on the east side of the Cascade Range in Washington and in the central Idaho mountains, and these areas may provide an essential "nucleus" for conservation strategies and ecosystem restoration. Strategies for improving the health of basin ecosystems can build on existing strengths. Improved understanding of change in vegetation patterns, causative factors, and links with disturbance processes will assist managers and policy makers in making informed decisions about how to address important ecosystem health issues.
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Institute of Forest Resources. 1988. Streamside Management: Riparian Wildlife and Forestry Interactions. Contribution No. 59. Seattle, WA: University of Washington.
Summary: This document is a compilation of papers presented at the "Riparian Wildlife and Forestry Interactions" symposium hosted by the College of Forest Resources and the College of Ocean and Fishery Sciences on February 11-13, 1987 at the University of Washington in Seattle, Washington. The papers are organized into the following categories: Characteristics of Natural Riparian Forest Systems, Ecological Relationships of Riparian Systems and Associated Uplands, Comparisons of Communities in Managed and Unmanaged Riparian Systems, Current Riparian Forest Management Practices and Policies, and Social and Economic Factors That Influence Riparian Forest Management Decisions.
Knutson, K. L. and Naef, V. L. 1997. Management Recommendations for Washington`s Priority Habitats: Riparian. Olympia, WA: Washington Department of Fish and Wildlife.
Abstract: By virtue of its high productivity, diversity, continuity, and critical contributions to both aquatic and upland ecosystems, riparian habitat provides a rich and vital resource to Washington's fish and wildlife. Riparian habitat occurs as an area adjacent to rivers, perennial or intermittent streams, seeps, and springs throughout Washington. Because it is generally a narrow band, riparian habitat covers a relatively small portion of the state. Riparian areas contain elements of both aquatic and terrestrial ecosystems which mutually influence each other and occur as transitions between aquatic and upland habitats.
The Washington Department of Fish and Wildlife has developed statewide riparian management recommendations based on the best available science. Nearly 1,500 pieces of literature on the importance of riparian areas to fish and wildlife were evaluated, and land use recommendations designed to accommodate riparian- associated fish and wildlife were developed. These recommendations consolidate existing scientific literature and provide information on the relationship of riparian habitat to fish and wildlife and to adjacent aquatic and upland ecosystems. These recommendations have been subject to numerous review processes.
Recommendations on major land use activities commonly conducted within or adjacent to riparian areas are provided, including those relative to agriculture, chemical treatments, grazing, watershed management, roads, stream crossings and utilities, recreational use, forest practices, urbanization, comprehensive planning, restoration, and enhancement. Management recommendations for riaparian areas are generalized for predictable application across the Washington landscape . . .
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Kovalchik, B. L. and Chitwood, L. A. 1990. Use of Geomorphology in the Classification of Riparian Plant Associations in Mountainous Landscapes of Central Oregon, U.S.A. Forest Ecology and Management 33/34: 405-418.
Abstract: Resource managers are increasingly interested in the importance, unique values, classification, and management of riparian zones. Understanding the ecology of the riparian zone is complicated by extreme variation in geology, climate, terrain, hydrology, and disturbances by humans. As a result, it is often difficult to determine the vegetation potential of riparian sites and develop management options. A recent riparian classification in central Oregon uses geomorphology in addition to traditional floristic classification to help identify vegetation potential in the riparian zone. A four-level geomorphic/floristic classification is proposed. Geomorphology is especially useful on riparian sites where the natural vegetation composition, soils, and/or water regimes have been altered by past disturbance, either natural or human- induced.
Lehmkuhl, J. F., Hessburg, P. F., Everett, R. L., et al. 1994. Historical and Current Forest Landscapes of Eastern Oregon and Washington. Part I: Vegetation Pattern and Insect and Disease Hazards. PNW-GTR-328. Portland, OR: U.S. Department of Agriculture Forest Service.
Abstract: We analyzed historical and current vegetation composition and structure in 49 sample watersheds, primarily on National Forests, within six river basins in eastern Oregon and Washington. Vegetation patterns were mapped from aerial photographs taken from 1932 to 1959, and form 1985 to 1992. We described vegetation attributes, landscape patterns, that range of historical variability, scales and change, and disturbance hazards. The distribution of forest age classes and structure has changed, with smaller area in early-seral and old forest stages and greater area in multiple-canopy young and mature stands.
MacDonald, L. H., Smart, A. W. and Wissmar, R. C. 1991. Monitoring Guidelines to Evaluate Effects of Forestry Activities on Streams in the Pacific Northwest and Alaska. EPA/910/9-91-001. Seattle, WA: U.S. Environmental Protection Agency, Region 10.
Abstract: This document provides guidance for designing water quality monitoring projects and selecting monitoring parameters. Although the focus is on forest management and streams in the Pacific Northwest and Alaska, a broader perspective is taken, and much of the information is more widely applicable.
Part I reviews the regulatory mechanisms for nonpoint source pollution and defines seven types of monitoring. A step-by-step process for developing monitoring projects is presented. Because monitoring is a sampling procedure, study design and statistical analysis are explicitly addressed. The selection of monitoring parameters is defined as a function of the designated uses, management activates, sampling frequency, monitoring costs, access, and the physical environment. Approximately
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30 parameters are rated with regard to these controlling factors. A qualitative combination of these rankings yields recommended monitoring parameters for various management activities. This parameter selection process has been incorporated into an interactive PC-based expert system called PASSSFA.
Part II is a technical review of the parameters, which are grouped into six categories: physical and chemical constituents, flow, sediment, channel characteristics, riparian, and aquatic organisms. The review of each parameter is organized into seven sub- sections: definition, relation to designed uses, response to management activities, measurement concepts, standards, current uses, and assessment.
McGreer, D. J. 1996. Considerations in Development of Riparian Management Strategies: Potential Consequences of Wildfire on Riparian and Aquatic Systems. Inherent Disturbance Regimes: A Reference for Evaluating the Long-Term Maintenance of Ecosystems. Unpublished manuscript, Lewiston, ID.
Abstract: Active management strategies that incorporate and carefully manage disturbance processes to achieve desired future vegetation and habitat conditions within watersheds and their riparian areas provide the highest potential for restoring and maintaining ecosystem functions and processes, and for achieving fully functioning riparian systems. Passive riparian management strategies allow riparian vegetation to become unnaturally dense and fire-pone, inevitably and unnecessarily predisposing riparian and aquatic systems to destruction by catastrophic wildfire.
McKenzie, D., Peterson, D. L., Alvarado, E. 1996. Predicting the Effect of Fire on Large- Scale Vegetation Patterns in North America. PNW-RP-489. Portland, OR: U.S. Department of Agriculture Forest Service.
Abstract: Changes in fire regimes are expected across North America in response to anticipated global climatic changes. Potential changes in large-scale vegetation patterns are predicted as a result of altered fire frequencies. A new vegetation classification was developed by condensing Kuchler potential natural vegetation types into aggregated types that are relatively homogeneous with respect to fire regime. Transition rules were developed to predict potential changes from one vegetation type to another because of increased fire frequency. In general, vegetation currently associated with warmer or drier climates could replace existing vegetation in most biomes. Exceptions ware subalpine forests and woodlands at the Arctic treeline, which are predicted to become treeless. The transition rules provide an ecological perspective on possible new configurations of vegetation types, a set of constraints for steady-state models, and a potential method of calibration for dynamic models of large-scale vegetation change.
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Obedzinski, R. A., Shaw, C. G., Neary, D. G. 2001. Declining Woody Vegetation in Riparian Ecosystems of the Western United States. Western J. of Applied Forestry 16(4): 169-181.
Abstract: Riparian ecosystems serve critical ecological functions in western landscapes. The woody plant components in many of these keystone systems are in serious decline. Among the causes are invasion by exotic species, stress-induced mortality, increases in insect and disease attack, drought, beaver, fire, climatic changes, and various anthropogenic activities. The latter include agricultural development, groundwater depletion, dam construction, water diversion, gravel mining, timber harvesting, recreation, urbanization, and grazing. This article examines the factors implicated in the decline and discusses the importance of interactions among these factors in causing decline. It also clarifies issues that need to be addressed in order to restore and maintain sustainable riparian ecosystems in the western United States, including the function of vegetation, silvics of the woody plant species involved, hydrologic condition, riparian zone structure, and landscape features, geomorphology, and management objectives.
Oliver, C. D., Irwin, L. L. and Knapp, W. H. 1994. Eastside Forest Management Practices: Historical Overview, Extent of Their Applications, and Their Effects on Sustainability of Ecosystems. PNW-GTR-324. Portland, OR: U.S. Department of Agriculture Forest Service.
Abstract: Forest management of eastern Oregon and Washington began in the late 1800s as extensive utilization of forests for grazing, timber, and irrigation water. With time, protection of these values developed into active management for these and other values such as recreation. Silvicultural and administrative practices, developed to solve problems at a particular time have lingered and created confusion and consternation when knowledge, values, and vegetation conditions have changed. The present condition of most eastern Oregon and Washington forests is the result of disturbance and regrowth processes coupled with historical management practices. Most areas contain high levels of insects, diseases, and fuels. Without many, diverse, creative, and active solutions, large fires and insect outbreaks will occur - with local loss of ecosystem and human values.
Ottmar, R. D. and Sandberg, D. V. 2001. Wildland Fire in Eastern Oregon and Washington. Northwest Science 75: 46-54.
Abstract: Wildland fire is a major disturbance agent that shapes the forest health, productivity, and ecological diversity of eastern Oregon and Washington. Fire behavior and the effects of fire on flora, fauna, soils, air, and water are in large part driven by the availability of fuels to consume and the meteorological influences during a fire. Vegetation succession, disturbance processes, and management practices have resulted in an increase of fuels and vulnerability to extreme fire behavior and detrimental fire effects. Hazards of fire are further increased by encroachment of dwellings into forests and rangelands. Prescribed fire, selective
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logging and mechanical fuel treatment are being used to reduce fire hazard, but there is disagreement as to appropriate balance and efficacy of these actions. New tools to (1) characterize fuelbeds: (2) predict mesoscale meteorology, fire behavior, fire effects, smoke production, and dispersal: and (3) demonstrate tradeoffs between prescribed fire and other fuel treatment methods are continually being improved to assist with wildland fire and prescribed fire decision making in eastern Oregon and Washington.
Pacific Biodiversity Institute. 2002. SAGE Pre-Fire Data. Unpublished data, Pacific Biodiversity Institute.
Abstract: Pacific Biodiversity Institute (PBI), under agreement with the Washington Department of Fish and Wildlife, has undertaken to assess the availability of data relevant to fire disturbance regimes in riparian habitats, and to synthesize metadata and contact information on data stewards. The purpose of this project is to enable the Department of Fish and Wildlife to more accurately examine the scientific background of the new forest practice rules.
A database was created in Microsoft Access to store the information collected during the course of this project. A table called ‘SAGE data’ contains records of each piece of information collected – the types of information are: GIS data sets, reports, databases, or field reports. Other information stored in the table include the agency responsible for the data, the availability of the data, an abstract and the purpose of the data, when the data or report was produced or released or when the data was updated, and other relevant facts. Information on data attributes recorded for each entry in a data set and the methods used to collect the data are stored in separate but linked tables, to maintain efficient use of the database. The information is most easily viewed by using the Sage Data Form, which shows related records in all three tables. This form opens automatically when you open the Access database.
Russell, W. H. and McBride, J. R. 2001. The Relative Importance of Fire and Watercourse Proximity in Determining Stand Composition in Mixed Conifer Riparian Forests. Forest Ecology and Management 150: 259-265.
Abstract: Factors related to the composition of riparian forest stands on three streams in the northern Sierra Nevada mixed conifer forest type were related to proximity to the water course and years since fire. Using a linear regression analysis 46 variables were correlated to the natural log of distance from the thalweg "In(distance)" including a highly significant positive correlation to dominance and percent canopy cover of conifers, and a significant negative correlation to the same variables when applied to hardwoods. Twenty six variables were correlated to years since fire "years" including similar correlations to the dominance and cover of hardwood and conifer species. However, the significance of the correlation and the degree of sample variability described by fire age was relatively low in comparison to that found for distance from the thalweg. In addition the relative frequency of fire scars increased in a linear fashion with distance from the watercourse. The results of
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this study indicate that the importance of fire as a determining influence on forest composition declines in proximity to the riparian zone.
Schmitt, C. L. 1999. Effects of Stocking Level Control on the Occurrence and Severity of Conifer Diseases in the Blue Mountains of Northeastern Oregon and Southeastern Washington. Report BMZ-99-01. Unpublished manuscript, U.S. Department of Agriculture Forest Service, Wallowa-Whitman National Forest.
Abstract: Stand management in the Blue and Wallowa Mountains is frequently done to directly address insect and disease activity or risks. Thinning of some form is the most frequently prescribed treatment. Specific guidelines are available for recommended stocking levels. Depending upon stand type and other conditions, there will often be positive and negative effects of these entries. A variety of mitigating measures are available to reduce or eliminate some of the detrimental effects. They just need to be used.
_____. 2002. Diseases of Conifers Associated with Riparian Communities in the Blue Mountains and Inland West. Unpublished manuscript.
Abstract: The incidence and severity of many tree diseases are influenced by the "site hazard" where the host occurs. Often, the moist cool conditions characteristic of lower slope riparian areas are conducive for the effective dispersal and subsequent infection by fungal spores. Most tree diseases, that are often spore-spread, will have higher incidence and infection severity in riparian areas, and these sites are often characterized as being "higher hazard sites" than upper slope locations that often also support the same conifer host species. Differences in disease incidence between riparian and upland sites is probably greatest in continental climates, characteristic of the southern and dryer portions of the Inland West. Maritime climates support mesic plant community types outside of riparian areas, and the gradient in differences in incidence of most diseases, moving upslope or away from riparian zones, should be expected to be less clear. Examples of these differences between disease incidence and severity are clearest in locations such as the Blue Mountains, where continental climate prevails.
Schmoldt, D. L., Peterson, D. L., Keane, R. E., et al. 1999. Assessing the Effects of Fire Disturbance on Ecosystems: A Scientific Agenda for Research and Management. PNW-GTR-455. Portland, OR: U.S. Department of Agriculture Forest Service.
Abstract: A team of scientists and resource managers convened 17-19 April 1996 in Seattle, Washington, to assess the effects of fire disturbance on ecosystems. Objectives of this workshop were to develop scientific recommendations for future fire research and management activities. These recommendations included a series of numerically ranked scientific and managerial questions and responses focusing on (1) links among fire effects, fuels, and climate; (2) fire as a large-scale disturbance; (3) fire-effects modeling structures; and (4) managerial concerns, applications, and decision support. At the present time, understanding of fire effects and the ability to
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extrapolate fire-effects knowledge to large spatial scales are limited, because most data have been collected at small spatial scales for specific applications. Although we clearly need more large-scale fire-effects data, it will be more expedient to concentrate efforts on improving the linking existing models that simulate fire effects in a georeferenced format while integrating empirical data as they become available. A significant component of this effort should be improved communication between modelers and managers to develop modeling tools to use in a planning context. Another component of this modeling effort should be improved communication between modelers and managers to develop modeling tools to use in a planning context. Another component of this modeling effort should improve our ability to predict the interactions of fire and potential climatic change at very large spatial scales. The priority issues and approaches described here provide a template for fire science and fire management programs in the next decade and beyond.
Schultz, E., Gehr, S. and O`Neal, S. 1993. Northeastern Washington National Forest Health Proposal. Okanogan, Colville, and Wenatchee National Forests: U.S. Department of Agriculture Forest Service.
Abstract: The Colville, Wenatchee, and Okanogan national forests in northeastern Washington State are sliding towards imbalance and poor health. Forest plans chart activities to help heal these national forests, but bold measures are required not to reverse the slide. This proposal lists projects which would aggressively implement forest plans in order to address the serious problem of declining forest health.
Swanson, F. J. n.d. Fire and Geomorphic Processes. In Unknown.
Abstract: Fire, geomorphic processes, and landforms interact to determine natural patterns of ecosystems over landscapes. Fire alters vegetation and soil properties which change soil and sediment movement through watersheds. Landforms affect fire behavior and form firebreaks which determine burn boundaries. Geomorphic consequences of fire in a landscape-ecosystem type are determined by (a) characteristics of the fire regime, mainly frequency and intensity; and (b) geomorphic sensitivity or erodibility of the landscape.
U.S. Department of Agriculture Forest Service. 1996. The Use of Fire in Forest Restoration. INT-GTR-341. Ogden, UT.
Abstract: The 26 pages of this document address the current knowledge of fire as a disturbance agent, fire history and fire regimes, applications of prescribed fire for ecological restoration, and the effects of fire on the various forested ecosystems of the north-western United States. The main body of this document is organized in three sections: Assessing Needs for Fire in Restoration; Restoration of Fire in Inland Forests; and Restoration in Pacific Westside Forests. These papers comprise the proceedings from a general technical conference at the 1995 Annual Meeting of the Society for Ecological Restoration, held at the University of Washington, Seattle, September 14-16, 1995.
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_____. 1997. An Assessment of Ecosystem Components in the Interior Columbia Basin and Portions of the Klamath and Great Basins. PNW-GTR-405. 4 vols. Portland, OR.
Abstract: The Assessment of Ecosystem Components in the Interior Columbia Basin and Portions of the Klamath and Great Basins provides detailed information about current conditions and trends for the biophysical and social systems within the Basis. This information can be used by land managers to develop broad land management goals and priorities and provides the context for decisions specific to smaller geographic areas. The Assessment area System lands, 10 percent of the Nation's BLM-administered lands, and contains about 1.2 percent of the Nation's population. This results in a population density that is less than and generally has a robust, diverse economy. As compared to historic conditions, the terrestrial, aquatic, forest, and rangeland systems have undergone dramatic changes. Forested landscapes are more susceptible to fire, insect, and disease that under historic conditions. Rangelands are highly susceptible to noxious weed invasion. The disturbance regimes that operate on forest and rangeland have changed substantially, with lethal fires dominating many areas where non-lethal fires were the norm historically. Terrestrial habitats that have experienced the greatest decline include the native grassland, native shrubland, and old forest structures. There are areas within the Assessment area that have higher diversity than introduction of non-native fish species has complicated current status of native fishes. Core habitat and population centers do remain as building blocks for restoration. Social and economic conditions within the Assessment area vary considerably, depending to a great extent on population, diversity of employment opportunities, and changing demographics. Those counties with the higher population densities and greater diversity of employment opportunities are generally more resilient to economic downturns. This Assessment provides a rich information base, including over 170 mapped themes with associated models and databases, from which future decisions can benefit.
_____. 2000. Environmental Effects of Postfire Logging: Literature Review and Annotated Bibliography. PNW-GTR-486. Portland, OR.
Abstract: The scientific literature on logging after wildfire is reviewed, with a focus on environmental effects of logging and removal of large woody structure. Rehabilitation, the practice of planting or seeding after logging, is not reviewed here. Several publications are cited that can be described as "commentaries," intented to help frame the public debate. We review 21 postfire logging studies and interpret them in the context of how wildfire itself affects stands and whatersheds. Results of this review are summarized in 16 major conclusions at the end of the text, most of which are based on results of no more than a handful of studies. The review is followed by an annotated bibilography and an index. Copies of all papers reviewed here are held by the Blue Mountains Natureal Resource Institute, at the Forestry and Range Sciences Laboratory, Pacific Northwest Research Station, La Grande, Oregon.
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Highly Relevant Studies
Agee, J. K. and Maruoka, K. R. 1994. Historical Fire Regimes of the Blue Mountains. Technical Notes from the Blue Mountains Natural Resources Institute. Tech Notes #1: 1-7.
Summary: The authors discuss fire as a natural disturbance process in the Blue Mountains. The role of fire is described using the concept of the fire regime. Fire regimes are described for several vegetation types, as are adaptations of vegetation to fire.
Agee, J. K., Wright, C. S., Williamson, N., et al. 2002. Foliar Moisture Content of Pacific Northwest Vegetation and Its Relation to Wildland Fire Behavior. Unpublished manuscript, Seattle, WA.
Abstract: Foliar moisture was monitored for five conifers and associated understory vegetation in Pacific Northwest forests. Declines in foliar moisture of new foliage occurred over the dry season, while less variation was evident in older foliage. Late season foliar moisture ranged from 130 to 170 percent. In riparian-upland comparisons, largest differences were found for understory vegetation, with less variation evident for overstory trees. Minimum foliar moisture values of 100 to 120 percent are appropriate to use in crown fire risk assessment for the Pacific Northwest.
Barrett, S. W., Arno, S. F., and Menakis, J. P. 1997. Fire Episodes in the Inland Northwest (1540-1940) Based on Fire History Data. Ogden, UT: U.S. Department of Agriculture Forest Service.
Abstract: Information from fire history studies in the Northwestern United States was used to identify and map "fire episodes" (5 year periods) when fire records were most abundant. Episodes of widespread landscape-scale fires occurred at average intervals of 12 years. Mean annual acreage burned was calculated based on estimated areas of historical vegetation types with their associated fire intervals from the fire history studies. An average of about 6 million acres of forest and grass and shrubland burned annually with the 200 million acre Columbia River Basin study region, and especially active fire years probably burned twice this much area. For comparison, the largest known fire years since 1900 have each burned 2 million to 3 million acres in this region. We also compare the occurrence of regional fire episodes to drought cycles defined by tree-ring studies.
Bailey, R.G. 1995. Description of the ecoregions of the United States, 2nd Ed. Misc. Pub. No. 1391 (revised). Washington, DC: US Department of Agriculture Forest Service.
Abstract: This publication describes and illustrates a map showing the ecosystems of regional extent, or ecoregions, differentiated according to a hierarchical scheme modified from Crowley (1967), using climate and vegetation as indicators of the extent of each unit. RIPARIAN DISTURBANCE REGIMES IN EASTERN WASHINGTON Concurrent Technologies Corporation - 108 -
Camp, A. 1999. Age structure and species composition changes resulting from altered disturbance regimes on the eastern slopes of the Cascade Range, Washington. Journal of Sustainable Forestry 9(3/4).
Abstracts: Age and diameter distributions are powerful tools for assessing changes in forest structure and composition over time. This study analyzed the age distribution of 2,345 trees from 487 plots in the Eastern Washington Cascades to document increases in per-hectare tree densities and shifts in species composition since Euro-American settlement. Diameter distributions of these trees plus an additional 814 snags, stumps, and logs were analyzed to determine the extent and pattern of structural and compositional change resulting from post-settlement fire exclusion and preferential harvest of large ponderosa pine (Pinus ponderosa v. Dougl. Ex Laws.) and western larch (Larix occidentalis v. Nutt.). Per-hectare densities of most species increased following settlement, with shade-tolerant/fire- intolerant species showing the biggest gain. A comparison of diameter distributions for live and dead trees indicates existing stands may not provide snags and logs of adequate dimensions for future habitat needs. Changes in forest structure and composition over the past century increase risk for insect outbreaks, diseases, and catastrophic wildfires.
Covington, W.W. and M.M. Moore. 1992. Postsettlement changes in natural fire regimes: Implications for restoration of old-growth ponderosa pine forests. Journal of Sustainable Forestry 2: 153-181.
Abstract: Heavy livestock grazing and fire suppression associated with Euro- American settlement has brought about substantial changes in forest conditions in western forests. Thus old-growth definitions based on current forest conditions may not be compatible with the natural conditions prevalent throughout the evolutionary history of western forest types. Detailed analysis of data from two study areas in the southwestern ponderosa pine type suggests that average tree densities have increased from as few as 23 trees per acre in presettlement times to as many as 851 trees per acre today. Associated with these increases in tree density are increases in canopy closure, vertical fuel continuity, and surface fuel loadings resulting in fire hazards over large areas never reached before settlement. In addition, fire exclusion and increased tree density has likely decreased tree vigor (increasing mortality from disease, insect, drought, etc.), decreased herbaceous and shrub production, decreased aesthetic values, decreased water availability and runoff, decreased nutrient availability, changed soil characteristics, and altered wildlife habitat. To remedy these problems and restore these forest ecosystems to more nearly natural conditions, and maintain a viable cohort of old age-class trees, it may well be necessary to thin out most of the postsettlement trees, manually remove heavy fuels from the base of large, old trees, and reintroduce periodic burning.
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Dale, V. H. and Franklin, J. F. 1989. Potential Effects of Climate Change on Stand Development in the Pacific Northwest. Can. J. For. Res. 19: 1581-1590.
Abstract: Long-term climate and stand structure records and projections from a simulation model are used to explore effects of predicated changes in temperature on forest development in the Pacific Northwest. Few climate trends have occurred during the past 92 years, although there have been variations in September temperatures. The lack of climate trends makes it impossible to relate past changes in stand development to climate. Measures of stand development from six long-term forest plots over the past 7 decades are typical of Douglas-fir stands; stem density declines, leaf area stabilizes, aboveground biomass increases, and shifts in size distribution occur. These changes are consistent with patterns of natural succession. A computer model projected forest development under two climate scenarios: current temperature conditions and temperature warming (such as that predicted under a doubling of atmosphere CO2). The model predicted changes in species composition, leaf area, and stem density in response to temperature increases. Total aboveground biomass is not sensitive to the simulated temperature alterations. Predicted biomass stability suggests that the Pacific Northwest forest would continue to store large amounts of carbon in the living trees even with climatic warming. Therefore, the predicted temperature change would not alter the role of the Pacific Northwest forests as a major storage location of terrestrial carbon. Changes in precipitation patterns or in disturbance frequency or intensity that might occur with climatic warming could alter these predications.
Everett, R. L., Schellhaas, R., Keenum, D. et al. 2000. Fire History in the Ponderosa Pine/Douglas-Fir Forests on the East Slope of the Washington Cascades. Forest Ecology and Management 129: 207-225.
Abstract: We collected 490 and 233 fire scars on two ponderosa pine (Pinus ponderosa)/Douglas fir (Pseudotsuga meziesii) dominated landscapes on the east slope of the Washington Cascades that contained a record of 3901 and 2309 cross- dated fire events. During the pre-settlement period (1700/1750-1860), the Weibuil median fire-free interval (WMFFI) and the mean fire-free interval (MFFI) were 6.6-7 years at both sites. The MFFI during the settlement period (1860-1910) varied within 3 years of the pre-settlement value, but increased to 38 and 43 years for a truncated fire suppression period between 1910 and 1996. Increase variation in MFFI among aspect polygons suggest fire regimes have become more complex since Euro- settlement. In the pre-settlement period, an area equal to approximately 50 to 60 percent of the study area burned every 6 to 7 years, an amount of fire disturbance apparently in balance with landscape and stand vegetation structure. Overlapping fires have created a complex mosaic of different fire histories on these forested landscapes. Mapped fire events from the 1700 to 1910 showed 134 and 157 separate fire history polygons (FHP) at the two sites. Fire disturbance rates and patterns are suggested as ecologically defensible reference points for landscape heterogeneity to reduce the potential for catastrophic fires and to establish vegetation disturbance management guidelines.
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Everett, R., Baumgartner, D., Demietriev, V., et al. 2002. Russian Forests with an Intact Fire Regime Provide Forest Structure Reference Points for Altered Eastern Washington Forests. Unpublished manuscript.
Abstract: Fire regime, fire history and stand structure were defined for 14 mixed conifer stands on southerly aspects in both Eastern Washington (US) and in Siberia, Russia in 1997. Russian stands shared a common fire regime, but not fire history with US stands. Fire history of current Russian most closely matched that of US forest stands of 1796. Using the fire metric “FFI-out” (disturbance interval/recovery period ratio) we found Russian stands to be sustainable, but current US stands were not. Using the fire metric “FFI-out” we found Russian stands to be in a dynamic steady-state of post-fire recovery phases, but US forests were not. Using these same fire metrics US stands in 1796 were found to be both sustainable and in a dynamic steady state. If the sustainable US forest stands of 1796 are a desired condition then current Russian stand structure may serve as a reference point. Current Russian stands (and 1796 US stands by inference) had significantly (p < 0.05) fewer large and small trees (>, < 9 in. dbh), and small snags and logs than current US stands. Under the intact fire regimes of Russian forests the mean abundance per acre of trees, snags and logs (>16 in. dbh, dia.) was 18.3 [95 percent CI 26.6 to 9.9], 14.9 [95 percent CI 21.9 7.8] and 4.3 [95 percent CI 7.6 to 0.9], respectively.
Everett, R., Schellhaas, R., Ohlson, P., et al. 2002. Continuity in Fire Disturbance Between Riparian and Adjacent Sideslope Douglas-Fir Forests. Unpublished manuscript, Forest Ecology and Management.
Abstract: Fire-scar and stand-cohort records were used to estimate the number and timing of fire disturbance events that impacted riparian and adjacent sideslope Douglas-fir (Pseudotsuga menziesii) (Mirbel) Franco) forests. Data were gathered from 49 stream segments on 24 separate streams on the east slope of the Washington Cascade Range. Upslope forests had more "traceable" disturbance events than riparian forests in each of the valley types with a mean difference of 8 to 62 percent. Approximately 55 to 73 percent of the total traceable fire disturbance for a stream segment occurred on either sideslope and 24 to 27 percent in the riparian forest. Plant association groups in the riparian forest had 25 to 42 percent fewer fire disturbance events than the same plant association group upslope. Fewer traceable disturbance events in riparian forests may indicate a reduced disturbance frequency or a more severe disturbance regime or both. The two sideslopes on either side of the riparian forest shared the same fire event in 65 and 54 percent of the recorded fire events on east/west and north/south sideslopoes, respectively. Riparian forests share fire events with adjacent sideslope forests. Fire disturbance regimes of sideslope and riparian forests are quantitatively different, but interconnected through shared fire disturbance events. Disturbance events play a role in maintaining ecosystem integrity and we suggest that disturbance may need to be planned for in administratively defined riparian buffer strips to protect long-term ecological integrity of riparian and adjacent upslope forest.
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Flanagan, P., Morgan, P., Everett, R. 2002. Snag Recruitment in Subalpine Forests of the North Cascades, Washington State. PSW-GTR-181.
Abstract: We recorded snag species, locations, and casual agents of tree mortality, and estimated fire histories and standing dead and downed fuel abundance in polygons in subalpine forests in the Entiat watershed in Washington State. The overall snag density was 51+/- 5.2 snags per hectare. The density of dominant and codominant snags did not differ by aspect or slope categories (p=0.74), but the density of intermediate and suppressed snags was highest on steep south-facing slopes (p<0.05). Weather-related effects created more snags than any other disturbance in the period between stand-replacing fires. More weather-caused mortality occurred on northerly aspects than on southerly aspects (p<0.05) and on mid-slopes than either upper or lower slopes (p<0.05). Standing dead and downed fuel, and tree mortality caused by weather (snow, ice, and wind), root diseases, animals, and bark beetles were related to stand structural stage. We estimate the mean fire interval was 12 years for the 5,685 ha encompassed the study area. The estimated mean size of stand-replacing fires was 146+/- 95 ha.
Franklin, J. F., Spies, T. A., Van Pelt, R., et al. 2002. Disturbances and Structural Development of Natural Forest Ecosystems with Silvicultural Implications, Using Douglas-Fir- Forests as an Example. Forest Ecology and Management 155: 399- 423.
Abstract: Forest managers need a comprehensive scientific understanding of natural stand development processes when designing silvicultural systems that integrate ecological and economic objectives, including a better appreciation of the nature of disturbance regimes and the biological legacies, such as live trees, snags, and logs, that they leave behind. Most conceptual forest development models do not incorporate current knowledge of the; (1) complexity of structures (including spatial patterns) and developmental processes; (2) duration of development in long-lived forests; (3) complex spatial patterns of stands that develop in later stages of seres; and particularly (4) the role of disturbances in creating structural legacies that become key elements of the post-disturbance stands. We elaborate on existing models for stand structural development using natural stand development of the Douglas fir--western hemlock sere in the Pacific Northwest as our primary example; most of the principles are broadly applicable while some processes (e.g. role of epicormic branches) are related to specific species. We discuss the use of principles from disturbance ecology and natural stand development to create silvicultural approaches that are more aligned with natural processes. Such approaches provide for a greater abundance of standing dead and down wood and large old trees, perhaps reducing short-term commercial productivity but ultimately enhancing wildlife habitat, biodiversity, and ecosystem function, including soil protection and nutrient retention.
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Halpern, C. B. 1988. Early Successional Pathways and the Resistance and Resilience of Forest Communities. Ecology 69(6): 1703-1715.
Abstract: Vegetation changes were studied for 21 yr in two clearcut logged and slash-burned Pseudotsuga forests in the western Cascade Range of Oregon. Detrended correspondence analysis (DCA) was used to examine the successional relationships among six understory communities exposed to a gradient of disturbance intensity. Euclidean distances between pre and postdisturbance samples in ordination space were used to compare community resistance to disturbance and long-term recovery, or resilience. Ordination through time for plant communities revealed a common pattern of rapid floristic change away from predisturbance composition, followed by gradual, unidirectional return. Early, but transient, convergence of successional pathways was common among mesic- and dry-site communities, reflecting the broad distributions of colonizers and the floristic similarity of predisturbance understories. District sequences were observed on moist sites, reflecting more unique residual and colonizing floras. Ordinations also revealed increasing compositional change with disturbance intensity. Successional sequences were dominated by residual species on relatively undisturbed sites and by alternate suites of invading species on moderately disturbed and burned sites. Variation in the response gradient between watersheds reflected the modifying influence of local environment, stand history, and chance in succession.
Resistance and resilience varied little among plant communities but were generally lowest for the depauperate Coptis community and greatest for the compositionally and structurally diverse Plystichum and Rhododendron-Gaultheria types. Both measures were strongly influenced by disturbance intensity. The stability of Pseudotsuga understories derives from the moderate tolerance of initial understory dominants to burning and in their ability to subsequently perennate from subterranean structures. Variation in the long-term response of communities reflects complex interactions between species life history, disturbance intensity, and chance, suggesting that both deterministic and stochastic factors must be considered in evaluating community stability and response to disturbance.
Harrod, R. J., McRae, B. H. and Hartl, W. E. 1999. Historical Stand Reconstruction in Ponderosa Pine Forests to Guide Silvicultural Prescriptions. Forest Ecology and Management 114: 433-446.
Abstract: We reconstructed the historical stand structure and spatial patterning of fire-maintained ponderosa pine forests in the Eastern Cascades of Washington to develop and design silvicultural prescriptions to restore historical structure and composition. The structure of the dominant overstory was inferred from the size and spatial patterning of stumps, logs, snags, and live trees (>140 years of age) within 48 0.5 ha plots. Size class distributions, basal area, and spatial distribution of historical trees were compared among plant association groups representing a range of environmental conditions. Using spatial point pattern analysis, we found that significant clumping at fine scales (0-15 m) existed historically. Spatial patterning of
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present day and historical trees of four comparable plots suggest that while strong clumping exists in present day stands, the largest trees today exhibit less clumping than did large historical trees. Historical SDI (260) for dominant overstories was nearly the same as threshold for serious beetle mortality (263) for ponderosa pine. Cut-tree marking was carried out within 15 m radius circles, as guided by the spatial pattering analysis, and using a sliding scale of trees per circle by quadratic mean diameter.
Hemstrom, M. A., Korol, J. J. and Hann, W. J. 2001. Trends in Terrestrial Plant Communities and Landscape Health Indicate the Effects of Alternative Management Strategies in the Interior Columbia River Basin. Forest Ecology and Management 153: 105-126.
Abstract: Current and potential future conditions of terrestrial plant communities and landscape health were modeled for three alternative public land management strategies in the interior Columbia River basin. Landscape health was defined as an integration of the degree to which vegetation and disturbance conditions resemble native patterns and support levels of human activity. The range of vegetation and disturbance variability for a period before the middle 19th century was used as a basis for comparison of current and future regimes to the "historical" system. Departure from the "historical" regime in wildland environments was found to be related to altered disturbance patterns, especially changed fire regimes, forest insect and disease levels and excessive livestock grazing effects. Overall, mid-seral forest are currently more prevalent than they were in the past and old forests, especially single-layer structural types are less abundant. Non-native plant species and altered plant community composition conditions exist across broad areas of rangelands. Landscape health has declined substantially in many areas. Proposed management strategies that emphasize maintenance and restoration activities in a hierarchical landscape approach should generate improved landscape health conditions over the next 100 years. However, the massive scale of changes to disturbance and vegetation patterns from historical to current times and the cost of implementing restoration activities make dramatic improvement unlikely.
Hessburg, P. F., Smith, B. G., Miller, C. A., et al. 1999. Modeling Change in Potential Landscape Vulnerability to Forest Insect and Pathogen Disturbances: Methods for Forested Subwatersheds Sampled in the Midscale Interior Columbia River Basin Assessment. Portland, OR: U.S. Department of Agriculture Forest Service.
Abstract: In the interior Columbia River basin midscale ecological assessment, including portions of the Klamath and Great Basins, we mapped and characterized historical and current vegetation composition and structure of 337 randomly sampled subwatershed (9500 ha average size) in 43 subbasins (404,000 ha average size). We compared landscape patterns, vegetation structure and composition, and landscape vulnerability to 21 major forest insect and pathogen disturbances of historical and current forest vegetation overages. Forest vegetation composition, structure, and patterns were derived from attributes interpreted and mapped from aerial photographs
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taken from 1932 to 1966 (historical), and from 1981 to 1993 (current). Areas with homogeneous vegetation composition and structure were delineated as patches to a minimum size of 4 ha. Results of change analyses were reported for province-scale ecological reporting units (ERU's). In this paper, we report on methods used to characterize historical and current patch and subwatershed vulnerability to each of 21 insect and pathogen disturbance agents.
We assessed landscape vulnerability to defoliator, bark beetle, dwarf mistletoe, root disease, blister rust, and stem decay disturbances. We used patch composition, structure, logging disturbance, and physical environmental attributes to compare vegetation vulnerability of historical subwatersheds with that of their current condition. Patch vulnerability factors included items such as site quality, host abundance, canopy layers, host age of host size, patch vigor, patch (stand) density, connectivity of host patches, topographic setting, and presence of visible logging disturbance. Methods reported here can be used in landscape or watershed analysis to evaluate or monitor change in the magnitude and spatial pattern of vegetation vulnerability to insect and pathogen disturbances, and in planning to compare potential disturbance futures associated with alternative vegetation management scenarios.
Hessburg, P. F., Smith, B. G. and Salter, R. B. 1999. Using Estimates of Natural Variation to Detect Ecologically Important Change in Forest Spatial Patterns: A Case Study, Cascade Range, Eastern Washington. PNW-RP-514. Portland, OR: U.S. Department of Agriculture Forest Service.
Abstract: Using hierarchical clustering techniques, we grouped subwatersheds on the eastern slope of the Cascade Range in Washington State into ecological subregions by similarity of area in potential vegetation and climate attributes. We then built spatially continuous historical and current vegetation maps for 48 randomly selected subwatersheds from interpretations of 1938-49 and 1985-93 serial photos, respectively, and attributed cover types, structural classes, and potential vegetation types to individual patches by modeling procedures. We estimated a natural range of variation (NRV) in spatial patterns of patch types by subwatersheds and five forested ecological subregions. We illustrate how NRV information can be used to characterize the direction and magnitude of vegetation change occurring as a consequence of management.
Hood, W. G. and Naiman, R. J. 2000. Vulnerability of Riparian Zones to Invasion by Exotic Vascular Plants. Plant Ecology: 105-114.
Abstract: We compared the invasibility of riparian plant communities high on river banks with those on floodplain floors for four South African rivers. Analyses of abundant and significant riparian species showed that the floors have 3.1 times more exotic plants than the banks. The percent exotics ranges from 5 to 11 percent of total species richness for the banks, and from 20 to 30 percent for the floors. Species
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richness and percent exotics are negatively correlated for the banks, but not correlated for the floors.
Despite great differences in climate, species richness, and landuse history, the percentages of exotic plants in three rivers in the Pacific Northwest of the USA and one river in southwestern France are similar to those in South Africa (24 to 30 percent versus 20 to 30 percent, respectively). Furthermore, the high proportions of exotic species in these riparian plant communities are comparable to those reported for vascular plant communities on islands. We conclude that the macro-channel floor regions of the riparian zones of South African rivers are highly vulnerable to invasion by exotic vascular plants.
Johnson, S. L., Swanson, F. J., Grant, G. E., et al. 2000. Riparian Forest Disturbances by a Mountain Flood - the Influence of Floated Wood. Hydrological Processes 14: 3031- 3050.
Abstract: Large floods can have major impacts on riparian forests. Here we examine the variability and spatial distribution of riparian forest responses along eight third-to-fifth-order streams following a large flood (100 year recurrence interval) in the Cascade Mountain Range of Oregon. We categorized disturbance intensity (Physical force) exerted or riparian trees during floods into three classes (i) purely fluvial (high water flow only); (ii) fluvial supplemented by dispersed pieces of floating wood (uncongested wood transport); (iii) fluvial with movement of batches of wood (congested wood transport). These types of material transport and associated classes of disturbance intensity resulted in a gradient of biotic responses of disturbance severity ranging from standing riparian trees inundated by high water, to trees toppled but still partially rooted, to complete removal of trees. High within- stream and among-stream responses were influenced by pre-flood stream and riparian conditions as well as flood dynamics, especially the availability of individual pieces or congested batches of wood.
Fluvial disturbance alone toppled fewer riparian trees than in reaches where floodwaters transported substantial amount of wood. Debris flows delivered additional wood and sediment to parts of reaches of four of these study streams; riparian trees were removed and toppled for up to 1-5 km downstream of the debris flow tributary channel. Congested wood transport resulted in higher frequency of toppled trees and greater deposition of new wood levels along channel margins. The condition of the landscape at the time of a major flood strongly influenced responses of riparian forests. Recent and historic land-use practices, as well as the time since they previous large flood, influenced not only the structure and age of the riparian forests, but also the availability of agents of disturbance, such as large pieces of floating wood, that contribute to disturbance of riparian forests during floods.
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Johnston, J.G. 2002. Riparian Canopy Cover in Northeastern Washington: Stream Temperature Response, Historical Reference Conditions, and Management Effects. M.S. thesis, University of Washington.
Abstract: Northeastern Washington riparian forests have undergone changes to species composition and structure as a result of land management. Changes to riparian forests are of interest due to stream and forest health concerns. Timber harvest can reduce canopy cover and increase stream temperatures, while fire suppression, combined with the effects of past harvest, can alter stand conditions, with associated insect, disease, and wildfire risks. Riparian timber harvests aimed at reducing forest health risks may be in conflict with current policies that limit harvest to protect aquatic resources. Understanding how timber harvest affects stream temperature, how riparian management alters stand conditions, and how riparian canopy cover was historically distributed across the landscape will aid in the selection of appropriate riparian treatments. The first objective, to evaluate relationships between stream temperature and timber harvest in the study area, was accomplished by comparing stream temperatures in adjacent harvested / non-harvested reach pairs, and by regressing canopy cover against stream temperature. Paired- reach results were not statistically significant but linear regression showed a statistically significant increase of maximum temperature with a decrease in canopy cover. The second objective, to evaluate historical to current changes in riparian forest species composition and structure, was accomplished by comparing riparian stand conditions recorded in historical and current land surveys. Results showed a decrease in fire-adapted species and decreased tree size. The third objective, to investigate the historical distribution of riparian canopy cover on northeastern Washington streams, was accomplished by measuring cover using historical (1930s and 1940s) aerial photography. Cover levels were compared to several landscape variables and to four unique biophysical settings. Basin area, valley bottom width, surficial geology, and flow direction exhibited the best relations with canopy cover; elevation was a poor predictor of cover. The final objective, to evaluate the influence of management on riparian cover, was assessed using canopy cover and land management type measured from historical and current (1994 and 2000) aerial photographs. Reaches impacted by recent (within past 10 years) timber harvest showed a decrease in cover levels between the historical and current periods. Reaches without active management (only fire suppression) had greater cover levels than in the historical condition. Results indicated that for mature, fire-suppressed stands, if no greater than approximately 15% canopy cover was removed during timber harvest, then cover levels were likely to be retained near historical levels.
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Keane, R. E., Long, D. G., Menakis, J. P., et al. 1996. Simulating Coarse-Scale Vegetation Dynamics Using the Columbia River Basin Succession Model - CRBSUM. INT- GTR-340. Ogden, UT: U.S. Department of Agriculture Forest Service.
Abstract: The Columbia River Basin Succession Model (CRBSUM) simulates broad-scale landscape changes as a consequence of various land management policies. CRBSUM is a spatially explicit, deterministic model with stochastic properties that simulates changes in vegetation cover types and structural stages on landscapes over long periods. CRBSUM was used to simulate course-scale landscape changes in the Interior Columbia River Basin as a result of four management scenarios called management futures. CRBSUM results have an inherent 1 to 5 percent variability because of the stochastic structure of the model. Sensitivity analysis results suggest moderate changes in disturbance probabilities (25 percent increase) will only slightly affect simulated results.
Kovalchik, B.L. In press. Classification and management of Eastern Washington’s aquatic, riparian, and wetland sites – Part 1: The series descriptions. Colville, WA: US Department of Agriculture Forest Service.
Abstract: The area covered by this classification includes all riparian and wetland sites within the Colville, Okanogan, and Wenatchee National Forests. It covers aquatic, riparian, wetland, and transitional series and plant associations that: 1) occur repeatedly in Eastern Washington; 2) are large enough to be mapped for project-level wildland management; and 3) have distinct management differences. This classification supplements and expands information presented in upland forest plant association classifications in Eastern Washington.
Morse, R. A. 2000. Topographic and Physiographic Influences on Fire Severity in Stream Valleys of Northern Wenatchee National Forest. Ph.D. diss., University of Washington, College of Forest Resources.
Summary: This study identified trends in fire severity and pattern that area associated with topography and topographically influenced vegetation in stream valleys on the east side of the Cascade Mountains in Washington State. This study looked at multiple terrain variables within the 56,740 ha. burn perimeter of the 1994 Tyee Fire Complex. It was an observational study that sought to verify previously identified terrain influences on fire across a broader area and to identify issues that could merit further investigation. This study also addressed a particular issue that has not been examined in detail before the influence of stream confinement on fire severity.
Mutch, R.W. 1970. Wildland fires and ecosystems – A hypothesis. Ecology 51: 1046- 1051.
Abstract: Plant species which have survived fires for tens of thousands of years may not only have selected survival mechanisms, but also inherent flammable properties
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that contribute to the perpetuation of fire-dependent plant communities. This concept goes beyond the commonly accepted fire climate-fuel moisture basis of wildland fire occurrence. Plant communities may be ignited accidentally or randomly, but the character of burning is not random. The following hypothesis treats this interaction between fire and the ecosystem: Fire-dependent plant communities burn more readily than non-fire-dependent communities because natural selection has favored development of characteristics that make them more flammable. The hypothesis was experimentally derived following laboratory combustion tests with litter of eucalyptus (Eucalyptus obliqua v. L’Herit), ponderosa pine (Pinus ponderosa v. Laws.), and tropical hardwood trees.
Nakamura, F., Swanson, F. J. and Wondzell, S. M. 2000. Disturbance Regimes of Stream and Riparian Systems - A Disturbance-Cascade Perspective. Hydrological Processes 14: 2849-2860.
Abstract: Geomorphological processes that commonly transport soil down hillslopes and sediment and woody debris through stream systems in steep, mountainous, forest landscapes can operate in sequence down gravitational flowpaths, forming a cascade of disturbance processes that alters stream and riparian ecosystems. The affected stream and riparian landscape can by viewed through time as a network containing a shifting mosaic of disturbance paths--linear zones of disturbance created by the cascading geomorphological processes. Ecological disturbances range in severity from effects of debris flows, which completely remove alluvium, riparian soil and vegetation along steep, narrow, low-order channels, to localized paths of trees toppled by floating logs along the margins of larger channels. Land-use practices can affect the cascade of geomorphological processes that function as disturbance agents by changing the frequency and spatial pattern of events and the quantity of size distribution of material moved. A characterization of the disturbance regime in a stream network has important implications for ecological analysis. The network structure of stream and riparian systems, for example, may lend resilience in response to major disturbances by providing widely distributed refuges. And understanding of disturbance regime is a foundation for designing management systems.
Olson, D. L. 2000. Fire in Riparian Zones: A Comparison of Historical Fire Occurrence in Riparian and Upslope Forests in the Blue Mountains and Southern Cascades of Oregon. Ph.D. diss., University of Washington, College of Forest Resources.
Abstract: Despite the ecological importance of fire in Pacific Northwest forests, its role in riparian forests is not well documented. This study reconstructed the historical occurrence of fire within riparian forests along different stream sizes within three different national forests in Oregon. Two study areas were located in mostly dry, low-severity fire regime forests in the Blue Mountains of northeastern Oregon (Dugout and Baker) and the third study area was located in more mesic, moderate- severity fire regime forests on the western slopes of the southern Oregon Cascades (Steamboat). Fire scar dates and tree establishment dates were determined from a total of 424 fire scarred tree wedges and 81 increment cores taken from 67 riparian
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and upslope plots. Based on the data from this study, fire was common historically in the riparian zones of all three study areas. Weibull median probability fire return intervals (WMPIs) for riparian forests in Dugout ranged between 13 and 14 years, and were only slightly longer than those for upslope forests (averaging one year longer). In Baker, differences between riparian and upslope forests WMPIs were greater, ranging between 13 and 36 years for riparian WMPIs, compared to 10 to 20 years for upslope WMPIs. However, futher analyses suggested that forest type and slope aspect play a larger role than proximity to a stream when it came to differentiating fire regimes in this study area. For both Dugout and Baker it appeared that stream channels did not necessarily act as fire barriers during the more extensive fire years. Steamboat riparian WMPIs were somewhat longer (ranging from 35-39 years) than upslope WMPIs (ranging 27-36), but these differences were not significant. Fires werer probably more moderate in severity and likely patchy, considering the incidence of fires occurring only at a riparian plot or an upslope plot within a pair, but not at both. It is possible that fire return interval lengths were associated with aspect, but more sampling would need to be done to show this. Based on the results from this study, it is evident that: 1) restoring fire, or at least conducting fuel reduction treatments, will be necessary to protect riparian forests in comparable forest ecosystems, 2) forests should be managed according to forest type, not just by proximity to a stream, and 3) historical recruitment of large woody debris was likely small but continuous for low-severity fire regime riparian forests, with a relatively short residence time, and patchy and more pulsed for the more moderate-severity fire regime forests.
Pearson, S. F. and Manuwal, D. A. 2001. Breeding Bird Response to Riparian Buffer Width in Managed Pacific Northwest Douglas-Fir Forests. Ecological Applications 11(3): 840-853.
Abstract: We examined the relative importance of riparian vs upland habitats to breeding birds by comparing species abundance, richness, and similarity of bird communities in managed Douglas-fir forests in western Washington State, USA. We also examined whether forested buffer strips along second-and third-order streams effectively maintain the pre-logging riparian breeding bird community by comparing species abundance, richness, and turnover among three treatments: (1) unharvested controls; (2) sites that were clear-cut, leaving a narrow (-14m) forested buffer on both sides of the stream; and (3) sites that were clear-cut, leaving a wide (-31m) forested buffer along both sides of the stream.
Deciduous trees, berry-producing shrubs, and other deciduous shrubs less common in adjacent upland forest characterized streamside zones. Despite different vegetation features, riparian and upland habitats did not differ in any measures of bird species, richness and composition. No species or species group was more abundant in the upland. Neotropical migrants, resident species, and species associated with deciduous trees and shrubs in forested habitats were more abundant in riparian habitats than a adjacent uplands. Total bird abundance and abundance of four species (American Robin [Turdus migratorius], Pacific-slope Flycatcher [Empidonax
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difficilis], Black-throated Gray Warbler [Denroica nigrescens], and Winter Wren [Troglodytes troglodytes]) were higher in riparian habitats. Abundance of these riparian associates was correlated with percent cover by berry-producing shrubs and the number of deciduous trees in the canopy.
We found that the number of breeding bird species on sites with narrow buffers increased from slightly fewer than controls before harvest to an average of 10 more species than controls after harvest, a change reflected in an average 20 percent increase in species turnover on narrow-buffer sites relative to controls. Total bird abundance did not differ between treatments and controls. Resident species, those species associated with shrubs in forested habitats and conifer trees, declined on both buffer treatments. Species associated with upland and riparian forests (Black- throated Gray Warbler, Golden-crowned Kinglet [Regulus satrapa], and Brown Creeper [Certhia americana]) decreased in abundance on riparian buffer treatments relative to controls, whereas species associated with open, shrubby, habitats (Dark- eyed Junco [Junco hyemalis], Cedar Waxwing [Bombycilla cedrorum], and Song Sparrow [Melospiza melodia]).
Romme, W. H. and Knight, D. H. 1981. Fire Frequency and Subalpine Forest Succession Along a Topographic Gradient in Wyoming. Ecology 62(2): 319-326.
Abstract: Differences in fire frequency and the rate of secondary succession following fire have had a major effect on the present composition of forest vegetation in a 4500-ha undisturbed watershed in the subalpine zone of the Medicine Bow Mountains, southeastern Wyoming, USA. Periodic fire coupled with slow secondary succession has perpetuated lodgepole pine forest on the upland, while mature Engelmann spruce-subalpine fir forests have developed in sheltered ravines and valley bottoms where fire is less frequent and succession following fire is more rapid and/or more direct. A graphic model is presented showing the relationship between topographic position, fire-free interval, and the occurrence of mature forests dominated by spruce and fir.
Scher, S. H. 1991. Post-Fire Recovery of Riparian Resources on the Idaho Batholith: A Geographic Information System Analysis. In GIS Applications in Natural Resources, Edited by Heit, M. and Heit, M. Fort Collins, CO: GIS World, Inc.
Abstract: This paper reports a GIS analysis of post-fire riparian resources in forested watersheds on the Lowman Ranger District of Boise National Forest. It explores the effects of wildfire on the interaction between streams and the adjacent terrestrial corridor. The paper also documents the contribution of GIS as an analytical tool in fire-recovery studies.
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Schellhaas, R., D. Spurbeck, P. Ohlson, et al. 2000. Report to the Colville National Forest on the Results of the Quartzite Planning Area Fire History Research. Wenatchee, WA: US Department of Agriculture Forest Service.
Abstract: A total of 1,301 individual fire scars were cross dated from 142 fire scar samples on 7,669 acres of forest service land within the Quartzite planning area on the Colville National Forest. The earliest fire discovered was in 1384; however, our effective fire history dates from 1671. Mean fire frequency interval (MFFI) within polygons was 8.3 years during the pre-settlement era (1670-1885) and 5.9 years during the settlement period (1886-1920). These fire frequencies are characteristic of a high frequency, low severity fire regime. The longest period between successive fires was 25 years prior to settlement era and 15 years during the settlement period. Fire frequency increased and fire size decreased during the settlement era. Mean fire size within polygons 1-7 was 1,076 acres during the pre-settlement period and 300 acres during the settlement era.
Swetnam, T. W. and Betancourt, J. L. 1997. Mesoscale Disturbance and Ecological Response to Decadal Climatic Variability in the American Southwest. Journal of Climate 11: 3128-3147.
Abstract: Ecological responses to climatic variability in the Southwest include regionally synchronized fires, insect outbreaks, and pulses in tree demography (births and deaths). Multicentury, tree-ring reconstructions of drought, disturbance history, and tree demography reveal climatic effects across scales, from annual to decadal, and from local (102 km2) to mesoscale (104-106 km2). Climate-disturbance relations are more variable and complex than previously assumed. During the past three centuries, mesoscale outbreaks of the western spruce budworm (Choristoneura occidentalis) were associated with wet, not dry episodes, conventional wisdom. Regional fires occur during extreme droughts but, in some ecosystems, antecedent wet conditions play a secondary role by regulating accumulation of fuels. Interdecadal changes in fire-climate associations parallel other evidence for shift in the frequency or amplitude of the Southern Oscillation (SO) during the past three centuries. High interannual, fire-climate correlations (r=0.7 to 0.9) during specific decades (i.e., circa 1780 to 1830 correspond with a decreased in SO frequency or amplitude inferred from independent tree-ring width, ice, core, and coral isotope reconstructions.
Episodic dry and wet episodes have altered age structures and species composition of woodland and conifer forests. The scarcity of old, living conifers established before circa 1600 suggests that the extreme drought of 1575-95 had pervasive effects on tree populations. The most extreme drought of the past 400 years occurred in the mid- twentieth century (1942-57). This drought resulted in boadscale plant dieoffs in shrublands, woodlands, and forest and accelerated shrub invasion of grasslands. Drought conditions were broken by the post 1976 shift to the negative SO phase and wetter cool season in the Southwest. The post-1976 shows up as an unprecedented surge in tree-ringgrowth within millennia-length chronologies. This unusual episode
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may have produced a pulse in tree recruitment and improved rangeland conditions (e.g., higher grass production), and the post-1976 wet period and their aftermaths offer natural experiments to study long-term ecosystem response to interdecadal climate variability.
Swetnam, T. W. and Lynch, A. M. 1993. Multicentury, Regional-Scale Patterns of Western Spruce Budworm Outbreaks. Ecological Monographs 63(4): 399-424.
Abstract: Tree ring chronologies from 24 mixed-conifer stands were used to reconstruct the long-term history of western spruce budworm (Choristoneura occidentalis) in northern New Mexico. Temporal and spatial patterns of budworm infestations (within-stand occurrences) and outbreaks (more-or-less synchronous infestations across many stands) were investigated to identify local-scale to regional- scale forest disturbance patterns. Nine regional-scale outbreaks were identified from 1690 to 1989. One ancient stand of Douglas -fir trees (Pseudotsuga menziesii) exceeding 700 yr in age revealed that budworms and overstory trees can coexist for extraordinary lengths of time. Using spectral analysis we found that the regional outbreak record contained important cyclical components with periods varying from ~20 to 33 yr. The statistically significant (P < .05) but variable periodicity of regional outbreaks suggests the forest-budworm dynamic is pseudoperiodic (i.e., a stable limit cycle or damped oscillator perturbed by noise).
Duration of infestations within stands was ~11 yr and has not obviously changed in the 20th century; however, infestations tended to be more synchronous among stands in this century than during earlier centuries. Regional budworm activity was low from the mid-1920's to late 1930's and mid-1960's to late 1970's, and the most recent outbreak, beginning in the late 1970's, was unusually severe. These results , and contrasting infestation patterns in mountain ranges with different land use histories, generally support a hypothesis that human-induced changes in Southwestern forests have led to more widespread and intense budworm outbreaks in the late 20th century.
Despite human-induced changes in the 20th century, climate variation also appears to have been important to budworm regimes in this century as well as in earlier times. Regional outbreaks in the 20th century tended to occur during years of increased spring precipitation, and decreased budworm activity coincided with decreased spring precipitation. No clear association with temperature was identified. Comparisons of regional outbreak history since AD 1600 with a reconstruction of spring precipitation from limber pine (Pinus flexilis) ring width chronologies also shows that periods of increased and decreased budworm activity coincided with wetter and drier periods, respectively. This finding contrasts with results from shorter time-scale studies conducted in northwestern U.S. and Canada (western spruce budworm) and eastern Canada (spruce budworm C. fumiferana), where low precipitation and/or warmer temperatures were generally associated with outbreaks. Different patterns of budworm population response to changing moisture regimes might be due to differences in regional forest-budworm systems, or to differences in spatial and temporal scales of observation.
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We conclude that changes in forest structure in the southwestern U.S. may have shifted the spatial and temporal pattern of budworm outbreaks. The dynamic behavior and statistically significant association between multi-century, regional budworm and climate time series also suggest that complex budworm dynamics are driven by a combination of internal and external factors.
Swetnam, T. W., Wickman, B. E., Paul, H. G., et al. 1995. Historical Patterns of Western Spruce Budworm and Douglas-Fir Tussock Moth Outbreaks in the Northern Blue Mountains, Oregon, Since A.D. 1700. PNW-RP-484. Portland, OR: U.S. Department of Agriculture Forest Service.
Abstract: Dendroecology methods were used to reconstruct a three-century history of western spruce budworm and Douglas-fir tussock moth outbreaks in the Blue Mountains of northeastern Oregon. Comparisons of 20th century Forest Service documentary records and host and nonhost tree-ring width chronologies provide an objective basis for distinguishing climatic effects from insect-caused defoliation effects. Budworm outbreaks were more confidently reconstructed than were tussock moth outbreaks. Since A.D. 1700, at least eight regional budworm outbreaks have occurred at intervals of about 21 to 53 years. Reduced radial growth caused by defoliation lasted from about 13 to 17 years. Two regional budworm outbreaks occurred during the 19th century, and at least three and possibly four regional outbreaks have occurred during the 20th century. These findings generally support the hypothesis that budworm outbreaks have increased in the frequency and severity in the 20th century in northeastern Oregon.
Tholen, R. D. 1999. Modeling Fire Effects on Stand Composition and Structure within Riparian Buffers in Dry Douglas-Fir/Ponderosa Pine Forests. Ph.D. diss., University of Idaho, College of Graduate Studies.
Abstract: The USDA, Forest Service and USDI, Bureau of Land Management have adopted riparian buffer systems to maintain and restore cold water fish habitats. The FIRESUM successional model was used to project the long-term effects of these buffers on forest ecological health and aquatic habitat conditions. FIRESUM was calibrated using stand data from sties along the North Fork Boise River, in south central Idaho, along with local weather and fuels information. The model's ability to replicate actual fire mortality as measured on the study plots was tested using chi square, ANOVA comparisons using the F-statistic, and Pearson's correlation statistical tests. These tests suggest that the model, as calibrated, accurately predicts tree mortality from fire within the study area.
Following model validation testing, three fire management scenarios were modeled for a 150 year period: low-intensity fire every thirty years, determined to be the historic fire regime; high-intensity fire at year 75; and no fire. Simulated forests were compared for their ability to persist following fire, and their ability to provide large woody debris and shade for aquatic habitats. Model results suggest that reinitiation of the native fire regime of low-intensity fire at a 30 year return interval will produce a
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forest more likely to persist and repeat following fire, and that will provide a more consistent amount of large woody debris recruitment and shade than the other scenarios tested. FIRESUM is a useful tool for managers to better understand the effect of their decisions on forest and aquatic habitats.
Thompson, A.J. and D.M. Shrimpton. 1983. Weather associated with the start of mountain pine beetle outbreaks. Canadian Journal of Forest Research 14: 255-258.
Abstract: Extreme weather conditions associated with mountain pine beetle outbreaks were evaluated by graphical techniques for six locations throughout British Columbia. Three major associations of extreme weather patterns with lodgepole pine growth and mountain pine beetle outbreaks were identified. Weather effects prior to, or early in, the growing season can reduce growth without releasing the beetle population. Weather conducive to beetle establishment and early brood development can occur too late in the season to have a noticeable effect on tree growth and therefore will not be recorded in the annual growth rings. Warm, dry periods during the summer are associated with tree growth reduction and the beginnings of outbreaks. In each of these three cases, extreme low precipitation levels were involved. Average precipitation in some months did not compensate for the effects of unfavorable extremes in other months on tree growth.
U.S. DEPARTMENT OF AGRICULTURE Forest Service. 2001. The Interior Columbia Basin Ecosystem Management Project: Project Data.
Abstract: In July 1993, President Clinton directed the Forest Service to "develop a scientifically sound and ecosystem-based strategy for management of eastside forests." Responding to this direction, the project was initiated by the United States Department of Agriculture Forest Service and the United States Department of Interior Bureau of Land Management.
Project Mission: Develop a scientifically sound and ecosystem based strategy for forest and rangelands administered by the Forest Service and Bureau of Land Management in the interior Columbia River basin and portions of the Klamath and Great Basins.
The project has compiled a CD-ROM set (series of five CD-ROMs) that includes digital versions of the spatial data, databases, metadata, and major scientific publication graphics compiled in support of the project.
Williamson, N. M. and Agee, J. K. 2002. Crown Fire Potential in Riparian and Upland Stand of Dry Pacific Northwest Forests. Unpublished manuscript, Seattle, WA.
Abstract: The potential for crown fire initiation (torching) and active crown fire spread was evaluated for riparian and upland forests of the Blue Mountains of northeastern Oregon. Torching potential was high in the Pinus ponderosa/Pseudotsuga menziesii, Abies grandis, and Abies lasiocarpa forest series,
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and in both riparian and upland forests under 90 percentile fire weather. The potential for active spread of crown fires was considerably less (in only 15 of 76 stands) with two-thirds of the susceptible stands in the Abies lasiocarpa series. Treatment priorities to reduce crown fire potential should focus on low elevation forests, and on the reduction of surface fuels and increase in height to live crown.
Williamson, N. M. 1999. Crown Fuel Characteristics, Stand Structure, and Fire Hazard in Riparian Forests of the Blue Mountains, Oregon. Ph.D. diss., University of Washington, College of Forest Resources.
Summary: This study investigated a number of factors (height to crown base, heat of ignition, foliar moisture content) that influence fire behavior and in particular influence crown fire behavior. This study also compared crown fire hazard between riparian and upslope stands in the Blue Mountains of northeast Oregon. The study area included forest stands in the Wallowa-Whitman National Forest in Northestern Oregon, the Malheur National Forest in Eastern Oregon, and Payette National Forest in Central Idaho.
Wischnofske, M. G. and Anderson, D. W. 1983. The Natural Role of Fire in Wenatchee Valley. U.S. Department of Agriculture Forest Service.
Abstract: The purposes of this study were to determine the natural frequency of fire and to recommend uses for prescribed fire in the habitats observed. Tables, photographs and drawings clearly illustrate the relationship of fire to vegetational succession in these habitats, relationships which can be used in scheduling fire prescriptions.
Wright, C. S. 1996. Fire History of the Teanaway River Drainage, Washington. Ph.D. diss., University of Washington.
Abstract: The fire history of the mixed-conifer forests of the lower Teanaway River drainage was reconstructed using dendrochronological techniques. Results confirmed that fires were a common disturbance in the watershed for at least the last 450 years, and that the fire regime was historically of low to moderate severity. Systematic fire- scar surveys conducted at 92 different points within the 30,000 ha study area revealed that fire frequency was quite variable, with Weibull median probability intervals ranging from 7.1 to 43.2 years (mean fire intervals ranged from 7.7 to 48.4 years). In addition, fire size varied widely; the majority of fires (51 percent) were less than 1000 ha, however, 11 fires (8 percent) greater than 5000 ha have occurred since 1720. Large fire years may be related to periods of below-average precipitation of varying length. Fire occurred in the late summer or fall, as indicated by the almost exclusive presence of fire scars in the latewood portion of the annual ring, or at the ring boundary. The study area experienced a dramatic decline in fire occurrence ca. 1900; natural fire rotations were 26, 29 and 369 years in the 1700s, 1800s and 1900s, respectively. This decline coincided with the beginning of a period of commercial timber harvesting and related management activates. Historically, fire was an
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important process that influenced the structure and composition of the mixed-conifer forests of the Teanaway River drainage. An understanding of the effects and influences of fires within this ecosystem type contributes valuable information that can be used for future forest planning and management activities.
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Other Highly Relevant References
Agee, J. K. 1988. Successional Dynamics in Forest Riparian Zones. In Streamside Management: Riparian Wildlife and Forestry Interactions (Contribution 59), edited by K.J. Raedeke. Seattle, WA: University of Washington Institute of Forest Resources.
Agee, J. K., Finney, M., and deGouvenain, R. 1990. Forest Fire History of Desolation Peak, Washington. Canadian Journal of Forest Research 20: 350-356.
Arno, S.F. 1988. Fire Ecology and Its Management Implications in Ponderosa Pine Forests. In Ponderosa Pine: The Species and its Management, edited by D.M. Baumgartner, D.M. and Lotan, J.E. Pullman, WA: Washington State University Cooperative Extension.
Arno, S.F. and Davis, D.H. 1980. Fire History of Western Redcedar/Hemlock Forests in Northern Idaho. In Proceedings of the Fire History Workshop, edited by M.A. Stokes and Dieterich, J.H. Gen. Tech. Rep. RM-81. US Department of Agriculture Forest Service.
Arno, S.F. and Petersen, T.D. 1983. Variation in Estimates of Fire Intervals: A Closer Look at Fire History on the Bitterroot National Forest. Gen. Tech. Rep. INT-301. Ogden, UT: US Department of Agriculture Forest Service.
Arno, S.F., Simmerman, D.G., and Keane, R.E. 1985. Forest Succession on Four Habitat Types in Western Montana. Gen. Tech. Rep. INT-42. US Department of Agriculture Forest Service.
Baker, W.L. 1992. Effects of Settlement and Fire Suppression on Landscape Structure. Ecology 73(5): 1879-1887.
Barrett, S.W. and Arno S. 1982. Indian Fires as an Ecological Influence in the Northern Rockies. Journal of Forestry 80: 647-651.
Baumgartner, D.M., Boyd, R.J., Breuer, D.W., and Miller, D.L. (Eds.). 1986. Weed Control for Forest Productivity in the Interior West. Pullman, WA: Washington State University Cooperative Extension.
Benda, L. and Cundy, T. 1990. Predicting Deposition of Debris Flows in Mountain Channels. Canadian Geotechnical Journal 27: 409-417.
Bilby, R.E. and Ward, J.W. 1987. Changes in Large Organic Debris Characteristics and Function with Increasing Stream Size in Western Washington. Weyerhaeuser Company Technical Report.
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Bilby, R.E. 1988. Interactions Between Aquatic and Terrestrial Systems. In Streamside Management: Riparian Wildlife and Forestry Interactions (Contribution 59), edited by K.J. Raedeke. Seattle, WA: University of Washington Institute of Forest Resources.
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Boyd, R.J. 1986. Caution-Silvicultural Weed Control May Not Improve Tree Performance. In Weed Control for Forest Productivity in the Interior West, edited by Baumgartner, D.M., Boyd, R.J., Breuer, D.W., and Miller D.L. Pullman, WA: Washington State University Cooperative Extension.
Brinson, M.M., Swift, B.L., Plantico, R.C., and Barclay, J.S. 1981. Riparian Ecosystems: Their Ecology and Status. Biological Services Program Rep. FWS-OBS-81/17. Kearneysville, WV: Eastern Energy Land Use Team [and] National Water Resources Analysis Group, U.S. Fish and Wildlife Service.
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Crouch, G.L. 1987. A Bibliography of Publications from Forest Service Animal Damage Research in the Pacific Northwest, 1961-1986. In Animal Damage Management in Pacific Northwest Forests, edited by Baumgartner, D.M., Mahoney, R.L., Evans, J., Caslick, J., and Breuer, D.W. Pullman, WA: Washington State University Cooperative Extension.
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Everett, R. L., Townsley, J., and Baumgartner, D. M. 2000. Mapping Wildfire Hazards and Risks: Inherent Disturbance Regimes: A Reference for Evaluating the Long-Term Maintenance of Ecosystems. Journal of Sustainable Forestry 11: 265-288.
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Harrod, R.J., Taylor, R.J., Gaines, W.L., et al. 1993. Noxious Weeds in the Blue Mountains. In Search for a Solution: Sustaining the Land, People, and Economy of the Blue Mountains, edited by Jaindl, R.G., and Quigley, T.M. Washington DC: American Forests (in cooperation with the Blue Mountains Natural Resources Institute).
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Whittaker, R.H. 1960. Vegetation of the Siskiyou Mountains, Oregon and California. Ecological Monographs 30: 279-338.
Wickman, B.E. 1978. Tree Mortality and Top-Kill Related to Defoliation by the Douglas- Fir Tussock Moth in the Blue Mountains Outbreak. Research Paper PNW-27. Portland, OR: US Department of Agriculture Forest Service.
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Williams, B.E. and Lillybridge, T. 1983. Forested Plant Associations of the Okanogan National Forest. R-6-Ecol-132-b. Portland, OR: US Department of Agriculture Forest Service.
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Relevant Summary Documents
Aber, J., Neilson, R. P., McNulty, S., et al. 2001. Forest Processes and Global Environmental Change: Predicting the Effects of Individual and Multiple Stressors. BioScience 51 No. 9: 735-751.
Abstract: An article reviewing the state of prediction of forest ecosystem response to envisioned changes in the physical and chemical climate. These results are offered as one part of the forest sector analysis of the National Assessment of the Potential Consequences of Climate Variability and Change. The article includes three sections: (1) a brief review of the literature on the effects of environmental factors on forest ecosystem function; (2) a summary of the results from the Vegetation/Ecosystem Modeling and Analysis Project (VEMAP); and (3) a brief review of other regional modeling efforts that have addressed climate change or have looked at the possible effects of other components of global change, using tropospheric ozone and nitrogen deposition as examples.
Agee, J. K. 1994. Fire and Weather Disturbances in Terrestrial Ecosystems of the Eastern Cascades. PNW-GTR-320. Portland, OR: U.S. Department of Agriculture Forest Service.
Abstract: Fire has been an important ecological process in eastside Cascade ecosystems for millennia. Fire regimes ranged from low severity to high severity, and historic fire return intervals ranged from less that a decade to greater than 300 years. Fire history and effects are described for grassland and shrubland ecosystems, and the range of forested communities by plant series: Ponderosa Pine, Douglas- fir/White fir/Grand fir, Lodgepole pine, Western hemlock/Western red cedar, and subalpine fir/Mountain hemlock. The riparian zones within these communities may be more or less impacted by fire. The effects of extreme weather events, including unusual temperature, wind, or moisture have generally had less significant impact than fire. Management practices, including fire suppression, timber harvesting, and livestock grazing, have altered historical fire regimes, in some cases irreversibly. The management issues for the 1990s include both management and research issues, at a grand scale with which we have little experience. Ecosystems and adaptive management principles will have to be applied.
_____. 1996. Achieving Conservation Biology Objectives with Fire in the Pacific Northwest. Weed Technology 10: 417-421.
Abstract: Fire has been a part of natural ecosystems for many millennia. The species of those ecosystems have evolved through a series of "coarse filters," one of which is resistance or resilience to disturbance by fire. Plant adaptations to fire include the ability to sprout, seed bank adaptations in the soil or canopy, high dispersal ability for seeds, and thick bark. These adaptations are often to a particular fire regime, or combination of fire frequency, intensity, extent, and season. Fire can be used by managers to achieve species to ecosystem-level conservation biology RIPARIAN DISTURBANCE REGIMES IN EASTERN WASHINGTON Concurrent Technologies Corporation - 137 -
objectives. Examples using prescribed fire include the grasslands of the Puget Trough of Washington State, maintenance of oak woodlands, and perpetuation of ponderosa pine/mixed-conifer forests.
Campbell, I. C. and Doeg, T. J. 1989. Impact of Timber Harvesting and Production on Streams: A Review. Aust. J. Mar. Freshwater Res. 40: 519-539.
Abstract: Timber harvesting operations have significant effects on both water quantity and water quality. The effects on water quantity have been well documented both in Australia and elsewhere. The effects on water quality are less widely appreciated, and include elevated concentrations of dissolved salts, suspended solids and nutrients, especially during peak flow periods. Several Australian studies have failed to measure peak flow transport of suspended solids, or have measured it inadequately, thus severely underestimating transport.
The major short-term effects of timber harvesting on the aquatic biota result from increased sediment input into streams or increased light through damage to, or removal of, the riparian vegetation. Sediment which settles on, or penetrates into, the stream bed is of more concern than suspended sediment, and can lead to long-term deleterious changes to fish and invertebrate populations. Increased light causes an increase in stream primary production which may increase invertebrate densities, and alter community composition. These biological consequences have not yet been adequately investigated in Australia. Longer-term effects, as yet not investigated in Australia, include changes to stream structure as the regrowth forest has fewer large logs to fall into the stream. These large logs play a major role as habitat and retention structures in streams.
There has been no attempt to evaluate the effects of timber production activities, including pesticide use and fuel reduction burning on the Australian stream biota. Likewise, although buffer zones are widely advocated as a protection measure for streams in Australia, there have been no studies to evaluate their effectiveness.
Campbell, S. and Liegel, L. 1996. Disturbance and Forest Health in Oregon and Washington. PNW-GTR-381. Portland, OR: U.S. Department of Agriculture Forest Service.
Abstract: The scope and intensity of disturbance by such agents as fire, insects, diseases, air pollution, and weather in Pacific Northwest forests suggests that forest health has declined in recent years in many areas. The most significant disturbances and causes of tree mortality or decline in Oregon and Washington are presented and illustrated. We discuss the interrelations of disturbance with forest management activities and the effect on native trees and suggest some solutions for reducing the severity of disturbance. One chapter reports on a forest health monitoring pilot project.
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Cowlin, R. W., Briegleb, P. A. and Moravets, F. L. 1942. Forest Resources of the Ponderosa Pine Region. Miscellaneous Publication No. 490. Washington DC: U.S. Department of Agriculture Forest Service.
Summary: This document is a forest inventory that consists of the following elements: (1) areas of the several forest types, by ownership and class; (2) areas of the even-aged immature conifer types, by age class and degrees of stocking, and uneven-aged immature conifer types, by degrees of stocking of poles and reproduction combined; (3) a classification of forest areas according to site quality; and (4) computation of the volume of the present timber stands, including residual stands on cut-over lands, by species and ownership class.
Dale, V. H., Joyce, L. A., McNulty, S., et al. 2001. Climate Change and Forest Disturbances. BioScience 51(9): 723-734.
Summary: Climate change can affect forests by altering the frequency, intensity, duration, and timing of fire, drought, introduced species, insect and pathogen outbreaks, hurricanes, windstorms, ice storms, or landslides.
Over geologic time, changes in disturbance regimes are a natural part of all ecosystems. Even so, as a consequence of climate change, forests may soon face rapid alterations in the timing, intensity, frequency, and extent of disturbances. The number and complexity of climate variables related to forest disturbance make integrated research an awesome challenge. Even if changes cannot always be predicted, it is important to consider ways in which impacts to forest systems can be mitigated under likely changes in disturbance regimes. The task for the next decade is to understand better how climate affects disturbances and how forests respond to them. Improved monitoring programs and analytical tools are needed to develop this understanding. Ultimately, this knowledge should lead to better ways to predict and cope with disturbance-induced changes in forests.
Daubenmire, R. 1956. Climate as a Determinant of Vegetation Distribution in Eastern Washington and Northern Idaho. Ecological Monographs 26(2): 131-154.
Summary: A review and study of whether the “universal” climatic classifications can accurately describe and/or predict patterns of vegetation in Eastern Washington and northern Idaho. The author tested the classifications of Koppen, Thornthwaite (1931, 1948), and Swain using established weather stations and vegetation maps, and found that the same climatic symbol was often used several different vegetational belts – and that even the distinction between grassland and forest climates could not be defined consistently. A different classification approach – using mean monthly temperatures plotted against median monthly precipitation – was found to be more successful in defining discrete “phytogeograhpic” units.
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Dent, L. F. and Walsh, J. B. S. 1997. Effectiveness of Riparian Management Areas and Hardwood Conversions in Maintaining Stream Temperature. Forest Practices Technical Report Number 3. OR: Oregon Department of Forestry, Forest Practices Monitoring Program.
Abstract: Temperature in forested streams is a critical component of fish habitat. Management alongside forested streams has the potential to significantly affect the amount of solar radiation reaching the stream surface as well as the condition of other environment parameters that are correlated with stream temperature response. In 1995, the Oregon Department of Forestry conducted a monitoring project to evaluate the effectiveness of the forest practice rule in preventing increases in stream temperature associated with forest harvesting. The project set out to answer the questions: Are the best management practices resulting in unacceptable temperature increases at the site and watershed level?
Temperatures recorded continuously on 13 stream reaches and one basin were used to analyze the effects of Riparian Management Areas (RMA's) and Hardwood Conversions (HWC's) on maintaining stream temperature throughout the summer lowflow season. RMA's are unmanaged forest buffers of varying widths depending on stream size and type situated between upslope harvest operations and streams. HWC's are managed riparian buffers that are capable of supporting conifers but which are currently dominated by hardwoods. Active management is not permitted within RMA (OAR 629-635-310) and is permitted within a HWC (OAR 629-640- 300). Using various statistical methods, including repeated measures on analysis of variance and distribution tests, stream temperatures recorded immediately below the harvest units were compared to control temperatures recorded above the harvest units and those recorded approximately 500 feet below the harvest units.
Results from this monitoring project are limited by lack of pre=harvest data and variability among the sample sites. Differences in elevation, harvest methodology, and georegion as well as data collection problems, especially with canopy cover, contributed to a highly variable sample population. However, consistent, if not significant, increases in stream temperature below harvested reaches indicated that the forest protection rules may not always provide adequate protection to meet water quality standards.
In general, the 7-day moving average of maximum, minimum and average temperature increased through the harvest units, whether it was a RMA or HWC. Average 7-day maximum increase for RMA's was 2.5 oF and 2.5 oF for HWC's. However, four out of eight streams experienced stream temperature increases greater that 3oF while only one out of five RMA streams showed increases greater that 3oF. When variance in temperature contributed by distance from divide was theoretically accounted for, temperature increases were not significant. Without accounting for the natural downstream increase in temperature, temperature increases throughout the harvest units were statistically significant. Depending on the position of the harvest units within a watershed, stream temperature did or did not decrease downstream
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again after returning to an unmanaged canopy. Those reaches that were sampled higher in the basin did show a corresponding decrease in temperature 500 ft downstream, while those reaches sampled lower in the basin did not show a decrease in stream temperature 500 ft downstream.
The water quality standard for the 7-day moving average of maximum (64oF) was exceeded more often downstream of harvested units that upstream. On all streams the standard was exceeded only 9.4 percent of the time. However only three of the thirteen streams never exceeded the water quality standard.
Continued monitoring and assessment will be completed to address the limitations of this monitoring project and attempt to better determine where rules can be improved and how forested stream systems respond to management.
Ferguson, S. A. 2001. Climatic Variability in Eastern Oregon and Washington. Northwest Science 75: 62-69.
Abstract: Climate is a driving factor in forest health and productivity that limits species survival and affects disturbance processes. Complex topography and mosaics of land cover compound the variability of climate in eastern Oregon and Washington. The area is a transition zone between marine, arctic, and continental influences with associated extremes in weather. Such extremes affect insect populations, animal migration, streamflow, flooding, and wildfire potential. Additionally, human activities such as deforestation and atmospheric pollution interact with climate, and may cause changes similar in magnitude to the glacial- interglacial epoch in the next 50 to 100 years. Effects of anthropogenic climate changes are ambiguous, however, and could counter-balance each other. For example, tree populations may have more difficulty reestablishing, but growth rates could accelerate. Conversely, management actions can mitigate the effect of climate on fisheries, water resources, wildfire, and floods. Also, management actions can affect climate by modifying carbon exchange and water and energy exchange between land and atmosphere. Models are increasingly able to predict climate variability and trends in climate-related disturbances such as wildfire.
Filip, G. M. 1995. Effects of Silvicultural Techniques on Forest Insects and Disease Pathogens in the Blue Mountains. Technical Notes from the Blue Mountains Natural Resources Institute: Tech Memo #7: 1-4.
Summary: An overview of how several silvicultural techniques affect forest insect and disease dynamics in the Blue Mountains of Oregon. Eight silvicultural techniques are examined: (1) precommercial thinning; (2) commercial thinning, seed tree and shelterwood harvesting; (3) sanitation-salvage harvesting; (4) clearcutting and regeneration; (5) uneven-age management; (6) prescribed burning; (7) stump treatments for root disease; and (8) fertilizing. It is stressed that the long-term effects of such practices are not well known.
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Franklin, J. F. and Dyrness, C. T. 1988. Natural Vegetation of Oregon and Washington. Corvallis, OR: Oregon State University Press.
Abstract: We present here a generalized account of the major vegetation types within the States of Oregon and Washington, an integration of the scattered information into a regional account. Published articles, theses, and personal data files are the source materials. The purpose is threefold: (1) to outline major phytogeographic units and suggest how they fit together and relate to environmental factors; (2) to direct the interested reader to sources of detailed information on the environment and vegetation of the Pacific Northwest, since such information connot be provided in an account of this size; and (3) to illustrate the major plant communities with photographs.
Graham, R. T., Harvey, A. E., Jain, T. B., et al. 1999. The Effects of Thinning and Similar Stand Treatments on Fire Behavior in Western Forests. PNW-GTR-463. Portland, OR: U.S. Department of Agriculture Forest Service.
Abstract: In the West, thinning and partial cuttings are being considered for treating millions of forested acres that are overstocked and prone to wildfire. The objectives of these treatments include tree growth redistribution, tree species regulation, timber harvest, wildlife habitat improvement, and wildfire-hazard reduction. Depending on the forest type and its structure, thinning has both positive and negative impacts on crown fire potential. Crown bulk density, surface fuel, and crown base height are primary stand characteristics that determine crown fire potential. Thinning from below, free thinning, and reserve tree shelterwoods have the greatest opportunity for reducing the risk of crown fire behavior. Selection thinning and crown thinning that maintain multiple crown layers, along with individual tree selection systems, will not reduce the risk of crown fires except in the driest ponderosa pine (Pinus ponderosa Dougl. ex Laws.) forests. Moreover, unless the surface fuels created by using these treatments are themselves treated, intense surface wildfire may result, likely negating positive effects of reducing crown fire potential. No single thinning approach can be applied to reduce the risk of wildfires in the multiple forest types of the West. The best general approach for managing wildfire damage seems to be managing tree density and species composition with well-designed silvicultural systems at a landscape scale that includes a mix of thinning, surface fuel treatments, and prescribed fire with proactive treatment in areas with high risk to wildfire.
Harvey, A. E. 1994. Integrated Roles for Insects, Diseases and Decomposers in Fire Dominated Forests of the Inland Western United States: Past, Present and Future Forest Health. In Assessing Forest Ecosystem Health in the Inland West. Edited by Sampson, R. N. and Sampson, R. N. Washington, D.C.: The Haworth Press.
Abstract: Forest ecosystems characterizing much of the Inland Western United States occupy precarious, changing environments that can be moisture, temperature, and/or nutrient limited. Rapid vegetative adaptations to inherent change are critical to both plant community stability and to the survival of individual species. Biological
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decomposition processes are often constrained and natural wildfires represent an important recycling agent. Recycling of resources is critical. It is proposed that native insect, disease and other decomposer activities, plus natural wildfire, historically provided coordinated biological and physical processes that were integral to carbon, nitrogen, and other nutrient cycling, and to rapid evolution and adjustment of native conifers (and of their ecosystems) in this dynamic environment. Current conditions, as imposed by traditional harvesting and fire control over the last 100 years, plus the introduction of white pine blister rust in the early 1930s, have changed many native vegetative and microbial systems. Endemic insects and diseases have to responded to these changes by increasing activities. Their effects counter many of the destabilizing actions of site deterioration, fuel accumulation, changes in species and genetic compositions, increased stand densities and impairment of recycling processes. At least in the short term, many ecosystems are now highly vulnerable to potential damage from high fuel wildfire and perhaps to the momentum of alternative biological decomposition processes. Genetic resources and other diversity components may be at especially high risk. Many current trends place future values in increasing danger until the course is changed. Adjusting cycle processes, stand density and species composition will often be more important than controlling individual pests when managing forest health for this region in the future.
Heinselman, M. L. 1981. Fire Intensity and Frequency as Factors in the Distribution and Structure of Northern Ecosystems. In Proceedings of the Conference Fire Regimes and Ecosystem Properties. Washington, D.C.: U.S. Department of Agriculture Forest Service.
Abstract: Most presettlement Canadian and Alaskan boreal forests and Rocky Mountain subalpine forests had lightning fire regimes of large-scale crown fires and high-intensity surface fires, causing total stand replacement on fire rotations (or cycles) of 50 to 200 years. Cycles and fire size varied with latitude, elevation, and topographic-climate factors. Some areas had smaller, less-intense surface fires at shorter intervals. The Great Lake-Acadian forests had regimes of short cycle crown fires in near-boreal jack pine and spruce forests, combinations of moderate intensity short-interval surface fires and small-scale crown fires at longer intervals in red-white pine forests, and low intensity long-interval fires in hardwoods. Fire maintained the structure and pattern of the forest mosaic. These regimes still prevail in the far north. Elsewhere regimes and the forest mosaic are greatly modified by logging, man- caused fires, and fire suppression.
Joyce, L., Aber, J., McNulty, S., et al. 2001. Potential Consequences of Climate Variability and Change for the Forests of the United States. In Forests, the Potential Consequences of Climate Variability and Change. Washington, D.C.: U.S. Department of Agriculture, Global Change Program Office.
Abstract: Forests cover nearly one-third of the US, providing wildlife habitat, clean air and water, cultural and aesthetic values, carbon storage, recreational opportunities such as hiking, camping, fishing, and autumn leaf tours, and products that can be
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harvested such as timber, pulpwood, fuelwood, wild game, ferns, mushrooms, and berries. This wealth depends on forest biodiversity-the variety of plants, animals, and microbe species, and forest functioning-water flow, nutrient cycling, and productivity. These aspects of forests are strongly influenced by climate and human land use.
Kauffman, J. B. c1990. Ecological Relationships of Vegetation and Fire in Pacific Northwest Forests. In Natural and Prescribed Fire in Pacific Northwest Forests, Walstad, J. D. et al. Corvallis, OR: Oregon State University Press.
Abstract: Through the millennia, fire has greatly affected the composition, structure, and numerous ecological processes of forest ecosystems in the Pacific Northwest. All forest organisms of the Pacific Northwest are intimately suited for survival in their environment, and this includes specific adaptations to ensure persistence following fire. Adaptations to fire might be best thought of as adaptations to survive within the given fire regime of an ecosystem. Therefore, species adaptation that facilitate survival in one fire regime may not necessarily ensure the same in another.
In general, adaptations to fire can be broadly generalized to include those traits which facilitate survival of the individual, and those traits which facilitate reproduction and, hence, perpetuation of the species. Examples of fire-survival traits include thick bark to protect living tissues or the capacity to sprout from below-ground organs. Thick bark is an effective insulator that can protect cambial tissues from damage by surface fires. Bark can also protect dormant buds on trunks and main branches in epicormically sprouting species. Among sprouters, plant age, phenology, and vigor can affect a species; capacity to sprout following fire. Fire severity (I.e., the level of fire intensity and/or fuel consumption) will greatly influence plant survival. For example, thick bark is a adaptation for survival in regimes of low-intensity surface fires, but of little value in severe, stand-replacement fires.
Numerous seedlings from species which require fire for flower stimulation, seed dispersal, or seed scarification and mineral soil exposure for germinations and establishment will be present following fire. However, low-consumption fires may not scarify dormant seeds in the soil or create bare mineral soil conditions required by some species to establish. Conversely, high-consumption fires may kill large numbers of dormant seeds, resulting in decreased seedling densities. These high- severity fires would, however, result in large are of bare ground, facilitating establishment of windborne seeds with a mineral seedbed requirement.
The functional role of coarse woody debris includes nutrient and carbon storage, sites for plant establishment, the maintenance of soil stability, and the presence of wildlife habitat. In many ecosystems, fire is an important disturbance which influences both input and disappearance of coarse woody debris. In regimes characterized by stand- replacements fires, huge inputs of coarse woody debris occur following fire. In regimes characterized by frequent surface fires, the input may be relatively continuous, with small quantities added with each fire. Consumption by fire may be
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the primary means of disappearance of coarse woody debris in regimes with frequent fire return intervals, whereas decay or decomposition is more important in forest with long fire return intervals.
Changes in forest structure caused by land-use activities can greatly alter fire regimes, resulting in changes in species composition, ecosystem functions, and success ional dynamics. Fire suppression and livestock grazing have effectively eliminated the frequent surface fires that characterized the fire regimes of many ponderosa pine and mixed-conifer forests. As a result, fire-intolerant, shade-tolerant conifers have increased, forest insect outbreaks and fuel loads have increased, and habitat diversity and forage production have decreased. Severe stand-replacement fires now occur. On the other hand, in Douglas-fir and Sitka spruce forests of western Oregon and Washington, clear-cut and burn rotations of 60-100 year intervals now occur where the natural fire return intervals were 250-500 years or more. These changes have altered forest structure, ecosystem function, and wildlife habitats.
Prescribed burning can be utilized in a positive manner when resource managers are aware of the historical role and ecological influences of fire in forest ecosystems. Knowledge of the vegetation response and potential effects on forest composition and productivity is necessary in order to improve managerial decisions concerning the use of prescribed fire.
Kilgore, B. M. 1981. Fire in Ecosystem Distribution and Structure: Western Forests and Scrublands. In Proceedings of the Conference Fire Regimes and Ecosystem Properties. Washington, D.C.: U.S. Department of Agriculture Forest Service.
Abstract: Fire plays an important role in determining structure of forests and scrublands throughout the West. Distribution and structure of vegetation depends upon topography, climatic regime, and fire regime. Six fire regimes of defined based on fire frequency and intensity, varying from frequent, low-intensity surface fires to very long return interval, stand replacement fires. In certain western forests and scrublands fire suppression for the past 50 to 100 years has lead to longer intervals between fires, increases in surface and crown fuels, changes in forest structure, and sequential impacts on fire intensity, postfire age stucture, species composition, fuel accumulation, and both hoirzontal and vertical pattern. Better understanding of fire regimes is basic to our management of western ecosystems.
Kirschbaum, M. U. F. and Fischlin, A. 1995. Climate Change Impacts on Forests. In Climate Change 1995: Impacts, Adaptations and Mitigation of Climate Change: Scientific-Technical Analyses. Cambridge: Cambridge University Press.
Summary: The authors summarize available information on the sensitivity of forests to climate change. Observations from the past, experimental studies, and simulation models based are used to support the authors' conclusions. Regional assessments for tropical, temperate, and boreal forests are presented. A number of conclusions are
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presented along with the level of confidence associated with the likelihood of the stated conclusions actually occurring.
Kovalchik, B. L. 1987. Riparian Zone Associations:Deschutes, Ochoco, Fremont, and Winema National Forests. Region 6 Ecology Technical Paper 279-87. Bend, OR: U.S. Department of Agriculture Forest Service.
Abstract: The classification covers riparian and transitional associations that: (1) occur repeatedly in Central Oregon; (2) are large enough to be mapped for project level wildland management; and (3) have distinct management differences. This classification supplements and expands the riparian information presented in plant association guides by Hall (1973), Volland (1976), Hopkins (1979) and Hopkins and Kovalchik (1983).
McCullough, D. G., Werner, R. A. and Neumann, D. 1998. Fire and Insects in Northern and Boreal Forest Ecosystems of North America. Annu. Rev. Entomol. 43: 107-127.
Abstract: Fire and insects are natural disturbance agents in many forest ecosystems, often interacting to affect succession, nutrient cycling, and forest species composition. We review literature pertaining to effects of fire-insect interactions on ecological succession, use of prescribed fire for insect pest control, and effects of fire on insect diversity from northern and boreal forests in North America. Fire suppression policies implemented in the early 1900's have resulted in profound changes in forest species compositions and structure. Associated with these changes was an increased vulnerability of forest stands to damage during outbreaks of defoliating insects. Information about the roles that both fire and insects play in many northern forests is needed to increase our understanding of the ecology of these systems and to develop sound management policies.
Murray, M. P., Bunting, S. C. and Morgan, P. 1998. Fire History of an Isolated Subalpine Mountain Range of the Intermountain Region, United States. Journal of Biogeography 25: 1071-1080.
Abstract: Fire has historically been an important ecological component of forests in the Intermountain Region of the northwestern United States. This study is set in a small biogeographically disjunct mountain range. Our research objhectives were to (1) investigate the historical frequency, severity, size, and spatial pattern of fire; (2) determine if and how fire regimes have changed since Euro-American setlement; and (3) compare how fire regimes of a small isolated range compare to nearby, but considerably larger, mountain agglomerations. Our findings suggest that this mountain range has historically support fires typified by small size and high frequency, resulting in a high degree of spatial pattern complexity compared to mountain agglomerations. We also found disparity in size and burn severity solely within the study area based on the bisecting Continental Divide. Since the advent of Euro-American settlement in the 1870s, fire frequency and size of individual fire in the West Big Hole Range have significantly decreased resulting in an estimated
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87 percent reduction in area burned. We discuss potential relationships of mountain range isolation and fire regimes in the Intermountain Region. Furthermore,. We suggest that the relative small size of this mountain range predisposes it to greater anthropogenic effects upon fire occurrence.
National Interagency Fire Center. 2002. Historical Wildland Fire Statistics. Boise, ID: National Interagency Fire Center. http://www.nifc.gov/stats/historicalstats.html.
Abstract: This is a list of some of the most serious wildland fires in U.S. history. Some were significant because of their size, others because of the value of the resources lost. Some small, but very intense, fires were important because of the loss of lives and property. There have been larger fires than some of those included on this list, but few or none with greater impact on lives and resources.
Oliver, C. D., Irwin, L. L. and Knapp, W. H. 1994. Eastside Forest Management Practices: Historical Overview, Extent of Their Applications, and Their Effects on Sustainability of Ecosystems. PNW-GTR-324. Portland, OR: U.S. Department of Agriculture Forest Service.
Abstract: Forest management for eastern Oregon and Washington began in the late 1800s as extensive utilization of forests for grazing, timber, and irrigation water. With time, protection of these values developed into active management for these and other values such as recreation. Silvicultural and administrative practices, developed to solve problems at a particular time have lingered and created confusion and consternation when knowledge, values, and vegetation conditions have changed. The present condition of most eastern Oregon, and Washington forests is the result of disturbance and regrowth processes coupled with historical management practices. Most areas contain high levels of insects, diseases, and fuels. Without many, diverse, creative, and active solutions, large fires and insect outbreaks will occur--with local loss of ecosystems and human values.
Parsons, R. 1999. Historical Range of Variability Estimates for the Idaho Southern Batholith (Revised). Boise, ID: Boise Cascade Corporation.
Abstract: Revised Historical Range of Variability estimates are presented by class, cover type and Vegetation Growth Stage for each of the eleven forested habitat types within the Idaho Southern Batholith, an area of 2.4 million hectares located in the mountains of Central Idaho. All changes in outputs or assumptions from prior estimates are explicitly stated. Also includes powerpoint presentation materials.
Rogers, P. 1996. Disturbance Ecology and Forest Management: A Review of the Literature. INT-GTR-336. Ogden, UT: U.S. Department of Agriculture Forest Service.
Abstract: This review of the distrubance ecology literature, and how it pertains to forest management, is a resource for forest managers and researchers interested in
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disturbance theory, specific disturbance agents, their interactions, and appropriate methods of inquiry for specific geographic regions. Implications for the future of disturbance ecology-based management are discussed.
Schmitt, C. L. 1997. Insects and Diseases of Wetland Hardwoods in the Blue and Wallowa Mountains with an Emphasis on Aspen. Unpublished manuscript.
Abstract: Deciduous hardwood trees and woody shrubs comprise dominant vegetation in many wetland communities and are substantial components of most others in the Blue and Wallowa Mountains. Most common are species of alder (Alnus spp.), poplar (Populus spp.), willow (Salix spp.), dogwood (Cornus spp.), hawthorn (Crataegus spp.), maple (Acer spp.) and birch (Betula spp.). Although most prevalent along streams and rivers, these genera are also found in other wet sites including seeps, around springs, and adjacent to meadows. In the Blue and Wallowa Mountains, distribution of these wetland species is usually limited and seldom extends beyond the immediate wet microsites except in some mesic high elevation communities. In this discussion, riparian communities will specifically refer to those sites influenced by streams or rivers.
Future management practices in riparian communities aimed at restoration and regeneration will undoubtedly need to consider insect and disease activity in the hardwood species. Many insect and disease agents affect the establishment, growth, and productivity of hardwood tree species. Most of the research and documentation concerning the biology and epidemiology of insects and diseases of hardwoods has been done in other parts of the United States, where hardwoods have been an important timber commodity. It is known that throughout the Blue and Wallowa Mountains, hardwoods are host to a variety of leaf spots, rusts, shoot blights, stem cankers, stem decayers, and defoliating and wood-boring insects. However, information regarding insect and disease outbreaks, distribution, severity, specific to the Blue Mountains is almost non-existent. Historical records of insect and disease activity on hardwoods in the Blue and Wallowa Mountains, including probable epidemics, are almost non-existent.
Given the information available, the following discussion will center on the insects and diseases believed important to these communities of the Blue and Wallowa Mountains.
Smith, J. K. and Fischer, W. C. 1997. Fire Ecology of the Forest Habitat Types of Northern Idaho. INT-GTR-363. Ogden, UT: U.S. Department of Agriculture Forest Service.
Abstract: Provides information on fire ecology in forest habitat and community types occurring in northern Idaho. Identifies fire groups based on presettlement fire regimes and patterns of succession and stand development after fire. Describes forest fuels and suggests considerations for fire management.
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Sprugel, D. G. 1991. Disturbance, Equilibrium, and Environmental Variability: What is ‘Natural’ Vegetation in a Changing Environment? Biological Conservation 58: 1-18.
Abstract: To most early ecologists, the "natural" ecosystem was the community that would be reached after a long period without large-scale disturbance (fire, windstorm, etc.). More recently, it has been realized that in most areas some type of large-scale disturbance is indigenous, and must be included in any realistic definition of "naturalness". In some areas an equilibrium may exist in which patchy disturbance is balanced by regrowth, but in others equilibrium may be impossible because (1) individual disturbances are too large or infrequent; (2) ephemeral events have long- lasting disruptive effects; and/or (3) climate changes interrupt any movement toward equilibrium that does occur. Examples of non-equilibrium ecosystems include the African savannas, the Big Woods of Minnesota, the lodgepole pine forest of Yellowstone National Park, and possibly the old-growth Douglas-fir forests of the Pacific Northwest.
Where an equilibrium does not exist, defining the "natural" vegetation becomes much more challenging, because the vegetation in any given area would not be stable over long periods of time even without man's influence. In many areas it may be unrealistic to try to define the natural vegetation for a site; one must recognize that there are often several communities that could be the "natural" vegetation for any given site at any given time.
Steele, R. and Geier-Hayes, K. 1995. Major Douglas-Fir Habitat Types of Central Idaho: A Summary of Succession and Management. INT-GTR-331. Ogden, UT: U.S. Department of Agriculture Forest Service.
Abstract: This report summarizes important successional aspects of seven central Idaho Douglas-fir habitat types. The habitat types and phases are grouped geographically into west-central and east-central Idaho to differentiate site potential based on ponderosa pine occurrence. The role of fire and other management activities and their influence on common seral shrubs are herbs are discussed. Common seral tree species are included with discussions of natural and planted conifer regeneration and tree growth capability.
Stephenson, N. L. 1999. Reference Conditions for Giant Sequoia Forest Restoration Structure, Process, and Precision. Ecological Applications 9(4): 1253-1265.
Abstract: National Park Service policy directs that more natural conditions be restored to giant sequoia groves, which have been altered by a century of fire exclusion. Effects to find a reasonable and practical definition of "natural" have helped drive scientists and land managers to use past grove conditions as reference conditions for restoration. Extensive research aimed at determining reference conditions have demonstrated that past fire regimes can be characterized with greater precision than past grove structures. Difficulty and imprecision in determining past grove structure has helped fuel a debate between "structural restorationists," who
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believe that forest structure should be restored mechanically before fire is reintroduced, and "process restorationist," who believe that simple reintroduction of fire is appropriate. I evaluate old and new studies from sequoia groves to show that some of the fire without a preceding mechanical restoration may restore the pre Euro- American structure of sequoia groves, at least within the bounds of our imprecise knowledge of past grove structure. However, the same may not be true for all forest types that have experienced lengthily fire exclusion. Our ability to draw robust generalizations about fire's role in forest restoration will depend heavily on a through understanding of past and present interactions among climate, fire, and forest structure. Use of reference conditions will be central to developing this understanding.
Swanson, F. J. and Franklin, J. F. 1992. New Forestry Principles from Ecosystem Analysis of Pacific Northwest Forests. Ecological Applications 2(3): 262-274.
Abstract: Forest management practices on Federal lands in the Pacific Northwest of the United States have been the center of intense controversy. Conflicting value systems, new information, and new perspectives have fueled the debate over the balance between timber production and preservation of natural ecosystems. In this paper we consider examples from three aspects of forest management: (1) management of forest stands, (2) management of the patchwork of forest stands at the landscape scale, and (3) management of streams and riparian networks. In each of these cases we examine: management practices and perspectives of the recent past, findings from ecosystem research that are leading to change in those practices, resulting changes in management practices, and future research directions. We also suggest a path for future change, including systems for managing in the face of uncertainty.
Results of research in natural and managed forest and stream ecosystems have been pivotal in reassessment and redesign of management practices to provide a broader range of management options for society to consider. Results of studies of natural disturbance processes and their effects are used as reference points for management systems intending to sustain biological diversity and ecosystem productivity. Stand management practices, for example, are being modified to retain some live trees and greater amounts of dead woody debris, both standing and down, in areas that would instead be clear-cut under intensive plantation forestry practices. The motivations for these modified practices are to sustain biological diversity, including key wildlife species, and to maintain soil productivity. Models of alternative forest-cutting patterns at a landscape scale are being used to examine shift from the previous system of dispersing cutting units to a system involving greater aggregation of unites using designs to provide for species preferring forest interior habitat as well as species favoring edge and early seral habitats. As a result of ecosystem research, the management of stream and riparian networks can now be based on understanding of forest-stream interactions and designed within a drainage-basin context. Overall, emphasis in research and management seems to be in early stages of shifting from featured species--e.g. Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) and
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Northern Spotted Owl (Strix occidentalis caurina)--to ecosystems, and from the scale of forest stand to landscapes and the entire region.
In addition to the contributions of ecosystem research to redesign of management techniques, ecosystem scientists also have roles in the social processes for determining the future course of management of natural resources. An important medium for scientist participation is establishment of adaptive management programs, in which management activities are conducted as experiments to test hypotheses and develop information needed for future natural resource management.
Swetnam, T. W., Allen, C. D. and Betancourt, J. L. 1999. Applied Historical Ecology: Using the Past to Manage for the Future. Ecological Applications 9(4): 1189-1206.
Abstract: Applied historical ecology is the use of historical knowledge in the management of ecosystems. Historical perspective increase our understanding of the dynamic nature of landscapes and provide a frame of reference for assessing modern patterns and processes. Historical records, however, are often too brief or fragmentary to be useful, or they are not obtainable for the process or structure of interest. Even where long historical time series can be assembled, selection of appropriate reference conditions may be complicated by the past influence of humans and the many potential reference conditions encompassed by nonequilibrium dynamics. These complications, however, do not lessen the value of history; rather they underscore the need for multiple, comparative histories from many location for evaluating both cultural and natural causes of variability, as well as for characterizing the overall dynamical properties of ecosystems. Historical knowledge many not simplify the task of setting management goals and making decisions, but 20th century trends, such as increasingly severe wildfires, suggest that disregarding history can be perilous.
We describe examples from our research in the southwestern United States to illustrate some of the values and limitations of applied historical ecology. Paleoecological data from packrat middens and other natural archives have been useful for defining baseline conditions of vegetation communities, determining histories and rates of species range expansions and contractions, and discriminating between natural and cultural causes of environmental change. We describe a montane grassland restoration project in northern New Mexico that was justified and guided by an historical sequence of aerial photographs showing progressive tree invasion during the 20th century. Likewise, fire scar chronologies have been widely used to justify and guide fuel reduction and natural fire reintroduction in forests. A southwestern network of fire histories illustrates the power of aggregating historical time series across spatial scales. Regional fire patterns evident in thee aggregations point to the key role of interannual lags in response of fuel and fire regimes to the El Nino-Southern Oscillation (wet/dry cycles), with import implications for long-range fire hazard forecasting. These examples of applied historical ecology emphasize that detection and explanation of historical trends and variability are essential to informed management.
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Torgersen, T. R. 2001. Defoliators in Eastern Oregon and Washington. Northwest Science 75: 11-20.
Abstract: Defoliating insects are major disturbance agents affecting forest health and productivity in eastern Oregon and Washington. Information on the four main defoliators of conifers in eastern Oregon and Washington is abundant. Because of concerns about growth suppression and mortality of trees during widespread defoliator outbreaks, much research effort has been focused on these species. They are western spruce budworm (Choristoneura occidentalis), Douglas-fir tussock moth (Orgyia pseudotsugata), pandora moth (Coloradia pandora), and larch casebearer (Coleophora Laricella). Various interactions of defoliators with other system components and natural regulatory processes have been described, as have monitoring and suppression techniques using pheromone traps. Large-scale suppression projects using both chemical and biological materials have been used in attempts to control some defoliator outbreaks. While such suppression projects have prevented some tree mortality and growth loss, they have been largely ineffective in changing the outbreak behavior of these insects. Some suppression materials have undesirable side effects on non-target insects such as sensitive or endangered moths, butterflies, and skippers, or on other ecological processes. Successful control of larch casebearer has been achieved by introduction of parasitic wasps. For most defoliators, the recommended strategy is preventative: silvicultural treatment to promote a diversity of tree species, stand structures, and moderate stocking levels. Decision-support tools UPEST and UTOOLS analyze insect and disease risks, and the Forest Vegetation Simulator models effects of insects and disease on stand growth.
Wickman, B. E., Mason, R. R. and Swetnam, T. W. 1994. Searching for Long-Term Patterns of Forest Insect Outbreaks. In Individuals, Populations and Patterns in Ecology. Andover, Hampshire: Intercept Ltd.
Abstract: Climate and the anthropogenic transformation of forest ecosystems are important extrinsic influences on insect and host communities. When most of the forested areas come under the management of the Federal Government, around the start of the 20th century, all fires were suppressed where possible. This has been followed by the intensive harvesting of ponderosa pine, western larch, and Douglas- fir during the last 80 years, which has drastically changed the species composition of forest landscapes. Historically, the large expanses of open ponderosa pine forests, either in pure stands or dominated by that species, were probably regulated by bark beetles in old-age forests or fire in immature forests, resulting in mosaics of age classes. According to historic descriptions and inventory records, the stands were mostly old-age, open-grown, and dominated by pine as a disclimax species. The remaining old-growth, mixed-conifer forests at higher elevation and mesic sites have left tree-ring histories that indicate about 7 to 10 outbreak episodes of either budworm or tussock moth over the last 2 centuries. These outbreaks were often synchronous over large areas in the Blue Mountains and, according to tree rings, were often characterized by heavy defoliation.
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The current forests have been altered so that shade-tolerant fir grows on many pine sites formerly maintained in a seral state by fire. These 90 to 140-year-old fir stands now appear to be regulated by forest insects and diseases, especially budworm and tussock moth. Intensive population studies of tussock moth over the past 20 years indicate a pattern of periodic increases and declines caused by delayed density- dependent factors (Mason and Wickman, 1988). The outbreak patterns of budworm are not as clear. In some stands, both fir-invaded pine and historically mixed-conifer, the current outbreak has killed most of the host trees. This level of insect population and resulting host damage is highly unstable and probably new to the ecological history of the Blue Mountain landscapes.
The search for patterns in this study has been fruitful. Descriptions of forest composition were found in pioneer journals and inventory records. Prehistoric patterns in tree rings, indicating old outbreaks of defoliating insects were found. Patterns of short-term cyclical outbreaks of tussock moth were also found, but little evidence of regular outbreaks of budworm. The predictability of these patterns for use by pest managers, modelers and ecologists however, is clouded by major perturbations now occurring on a landscape scale, and by the changing composition of the forests as restoration projects are planned for vast areas of Blue Mountains.
Washington State Department of Natural Resources, Forest Health Program. 2002. Forest Health in Washington, 2000. Olympia, WA: Washington State Department of Natural Resources. http://www.wa.gov/dnr/htdocs/rp/forhealth/.
Summary: An on-line summary of insect and disease information relevant to forests of Eastern Washington. Contains information about recent outbreaks of defoliators, bark beetles, root diseases, needle diseases, other miscellaneous diseases, and animal damage. Also includes a list of strategies to improve forest health.
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Relevant Studies
Agee, J. K. 1998. Historic Vegetation in the Central Eastern Cascades of Washington. Unpublished manuscript, University of Washington, College of Forest Resources, Seattle, WA.
Abstract: This report is divided into two independent chapters. This first chapter deals with the concept of the historical range of variability of the major forest types in the central eastern Cascades of Washington. It summarizes concepts of ranges of variability, briefly summarizes the major forest types, develops equilibrium age structures, and applies these to develop historic ranges of forest structures across the landscape. The second chapter focuses on reconstructing the species composition and structure of the lower Teanaway River drainage lands currently owned and managed by the Boise Cascade Corporation. This reconstruction used early survey records from the General Land Office that were obtained from the Bureau of Land Management, and provides a snapshot of the late nineteenth century vegetation in the Teanaway.
Anderson, L., Carlson, C. E. and Wakimoto, R. H. 1987. Forest Fire Frequency and Western Spruce Budworm Outbreaks in Western Montana. Forest Ecology and Management 22: 251-260.
Abstract: Duration and intensity of western spruce budworm (Christoneura occidentalis Freeman) outbreaks have increased with the decrease in forest fire frequency in western Montana since 1910. Frequency of budworm outbreaks, however, was not affected. Feeding activity and fire occurrence were measured in 20 mixed Douglas-fir (Psuedotsuga menziesii var. glauca (Beissn.) Franco) -ponderosa pine (Pinus ponderosa var. Ponderosa Dougl.ex Laws.) stands representing dry Douglas-fir habitat types. Outbreak frequency, duration and intensity were inferred from analyses of radial increment cores and fire history from basal fire scars on old- growth pines and firs. Data were compared between the pre-fire suppression period (1814-1910) and the fire suppression period (1911-1983). Since 1910, Douglas-fir, a shade-tolerant conifer and host for budworm has invaded and dominated sites previously occupied by non-host ponderosa pine. This increase in the abundance of host is a response to decreased wildfire frequency and has resulted in stand conditions favorable for budworm populations, an important factor contributing to current widespread and damaging populations of western spruce budworm.
Judicious use of ground-fire, thinning, and other silvicultural treatments that favor seral non-host conifers, reduce stand density, and minimize the number of canopy layers in managed stands would reduce the amount and quality of budworm habitat and significantly reduce the risk of damaging outbreaks.
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Anderson, R. S. 1996. Postglacial Biogeography of Sierra Lodgepole Pine (Pinus contorta var. murrayana) in California. Ecoscience 3(3): 343-351.
Abstract: Plant macrofossils and pollen from 13 sites are used to reconstruct the biogeography of Sierra lodgepole pine (Pinus contorta Dougl. ex. Loud. var. murrayana), and its relationship to climate change, within the Sierra Nevada. During Late-Wisconsin deglaciation, lodgepole pine grew at least 500 m lower in elevation than today. Lodgepole pine was widely established within its modern elevational range between 10, 500 and 9,000 years BP. During the early Holocene, lodgepole pine remained an integral member on montane forest assemblages below its present elevational range. Macrofossil evidence suggests successive disappearance from most lower elevation sites between 9,000 and 6,750 years BP. A likely explanation suggests progressive climatic warming and drying of soils during the dry Holocene, causing local extermination at the lower elevation sites. Within its present elevational range, a lack of macrofossils and a decline in diploxylon pollen suggests possible absence of lodgepole pine near several sites during the middle Holocene, with the tree continuing a retreat to higher, cooler elevations during this time. A return to lower elevation sites after ca 700 years BP probably resulted from cumulative cooling during the Neoglacial. The postglacial migration pattern for Sierra lodgepole pine differs somewhat from that of the more widely distributed Rocky Mountain subspecies (P. contorta var. latifolia). While the pattern for the Rocky Mountain lodgepole was both latitudinal and elevational (only now reaching its northernmost extent in Canada [Cwynar & McDonald, 1987]), Sierra lodgepole's migration was largely elevational with little migrational lag. Additional paleo-sites south of the present distribution of ssp. murrayana will help to clarify any latitudinal movements during the late Wisconsin.
Arno, S. F., Smith, H. Y. and Krebs, M. A. 1997. Old Growth Ponderosa Pine and Western Larch Stand Structures: Influences of Pre-1900 Fires and Fire Exclusion. INT-RP- 495. Ogden, UT: U.S. Department of Agriculture Forest Service.
Abstract: Presents detailed age structure for two western larch stands that historically experienced frequent fires. Compares age structures of eleven ponderosa pine and western larch stands representing a broad range of sites that had frequent fires. Interprets causal factors possibly linked to variations in stand age structures.
Beard, T. H., Martin, N. E. and Adams, D. L. 1983. Effects of Habitat Type and Elevation on Occurrence of Stalactiform Blister Rust in Stands of Lodgepole Pine. Plant Disease 67: 648-651.
Abstract: Stalactiform blister rust, caused by Cronartium coleosporioides, occurs on hard pines throughout the northern United States and Canada. Locations of lodgepole pine reported in disease surveys of Idaho forests, 1968-1980, showed stalactiform blister rust occurring at elevations between 1,500 and 2,477m. Abies lasiocarpa/Xerophyllum tenax and A. lasiocarpa/Vaccinium scoparium were the most common habitat types supporting lodgepole pine and stalactiform blister rust.
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Benda, L. E. and Sias, J. C. 1998. Landscape Controls on Wood Abundance in Streams. Unpublished manuscript, Earth Systems Institute, Seattle, WA.
Abstract: Storage of large woody debris in streams is variable in time and space because wood recruitment and transport are driven by episodic disturbances that occur over cycles of decades to centuries. Collecting information on woody debris by strictly empirical means is hindered by time limitations of field studies and complexities of natural environments. As a consequence, the range and magnitude of variability of wood in streams are not well constrained To circumvent those limitations, long-term patterns of wood recruitment, transport, and storage are evaluated by employing simplified expressions to represent climatic, biotic, and geomorphic processes. Five universal landscape processes that govern wood storage are considered: (1) Frequency of stand-resetting disturbances and subsequent trajectories of forest biomass accumulation and stand mortality; (2) intensity of bank erosion and its spatial variance in a network; (3) temporal and spatial frequency of mass wasting; (4) fluvial transport controlled by number of upstream contributing segments and wood loss through export or valley floor storage; and (5) rates of wood decay. The structure of variability in wood abundance, in the form of frequency distributions, is predictably constrained by the general magnitude of landscape process rates and vegetative characteristics of streamside forests. Variations in these attributes within individual watersheds and across different regions alter patterns of wood abundance. Relationships among landscape process rates, their spatial variance in a basin or landscape, and the resulting shapes of frequency distributions of wood recruitment and storage constitute a set of general theoretical principles which have practical applications, including: (I) Providing a framework for constructing wood budgets, including estimating the range and magnitude of variability in wood abundance; (ii) generating testable hypotheses on current wood loading and future trends; and (iii) setting realistic targets for future wood recruitment and storage.
Bethlahmy, N. 1974. More Streamflow After a Bark Beetle Epidemic. Journal of Hydrology 23: 185-189.
Abstract: A beetle epidemic near the Continental Divide in Colorado destroyed the timber in two large drainages but bypassed a third drainage. Long-term streamflow records were available for the three drainages for the periods before and after the onset of the epidemic. Analysis of these records reveals that a major increase in streamflow occurred after the epidemic.
Bragg, D. C. 1997. Simulating Catastrophic Disturbance Effects on Coarse Woody Debris Production and Delivery. In Proceedings: Forest Vegetation Simulator Conference. Ogden, UT: U.S. Department of Agriculture Forest Service.
Abstract: For decades, coarse woody debris (CWD) recruitment has remained a largely unknown component of riparian zone management. The integration of the Forest Vegetation Simulator (FVS) and a mechanistic CWD recruitment post-
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processor (CWD) provided insights into some of the factors involved in CWD delivery though the comparison of two simulated catastrophic disturbances (a spruce beetle outbreak and a clearcut) and an unmanipulated old-growth control. Compared to the old-growth control, spruce beetle-impacted riparian forest varied the timing and increased the overall delivery of CWD, while to clearcut reduced delivery and in- stream loads for many years. This exercise also suggested that natural catastrophic disturbance in riparian forest may bolster CWD recruitment, a process that could prove beneficial in the recovery of CWD-depauperate streams.
Britton, D. L. 1990. Fire and the Dynamics of Allochthonous Detritus in a South African Mountain Stream. Freshwater Biology 24: 347-360.
Abstract: (1) Input of allochthonous material, standing stocks of benthic organic matter (BOM) and suspended particulate organic matter (POM) were measured in a south-western Cape mountain stream from March 1986 to February 1988. The surrounding fynbos-dominated catchment was subjected to a prescribed burn in March 1987. (2) Litter-fall in the pre-burn year exhibited a distinct seasonal pattern, with peak falls during the early summer. Although the riparian canopy was not directly affected by the fire, in that id did not burn, a heavy seasonal leaf-fall occurred shortly afterwards. The following summer, litter-fall was less than half that of the pre-burn summer. (3) Standing stocks of BOM were significantly higher in autumn than in winter in the pre-burn year and were inversely related to discharge. Despite the heavy post-burn leaf-fall and low litter-fall during the post-burn summer, there was no significant difference between pre and post-burn BOM standing stocks. (4) Proportions and quantities of fine benthic organic matter (FBOM) in the soft BOM fraction were significantly higher in the post-burn spring, and monthly accumulation of ultra-fine benthic organic matter (UBOM) was also significantly higher in the post- burn spring and summer. These results may reflect accelerated decay rates of BOM in response to enhanced post-burn nitrate concentrations in stream water. (5) Export of CPOM was low in comparison to FPOM and particularly to UPOM, and the stream appears to be highly retentive of CPOM. (6) The natural resilience of the riparian vegetation minimizes the potentially disturbing effects of fire on the stream environment. As a result, the prescribed burn had a less than expected effect on both standing stocks of BOM and the stream environment in general.
_____. 1991. Fire and the Chemistry of a South African Mountain Stream. Hydrobiologia 218: 177-192.
Abstract: The effects of a late-summer prescribed burn on the chemistry of a second-order mountain stream in the south-western Cape, South Africa were investigated. Nitrate concentrations in stream water were significantly higher during the winter of the post-burn year. Increased concentrations of chloride, bicarbonate, polyphenols and potassium and decreased sodium concentrations were also recorded. Concentrations of ammonium, phosphate, calcium, magnesium, total dissolved solids and hydrogen's ions were not significantly affected by the burn. Ionic export form the catchment was generally greater in the post-burn year. Apart from nitrate, however,
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values probably lie within the natural range of year-to-year variation. It is predicted that enhanced losses of nitrate will decrease progressively with the recovery of the vegetation and the re-establishment of soil/plant nutrient cycles. Atmospheric losses of nutrients in smoke were unquantified, but may be of more significance to site productivity than losses though surface runoff, which, in the case of nitrogen, appear to be compensated by precipitation inputs.
Brown, J. K. 1985. Fire Effects and Application of Prescribed Fire in Aspen. In Rangeland Fire Effects: A Symposium, Edited by Sanders, K. and Sanders, K. Boise, ID: Idaho State Office, USDI - Bureau of Land Management.
Abstract: The influence of low- and high-intensity fire on successional patterns of climax and seral aspen (Populus tremuloides) is discussed. Mechanisms of aspen regeneration and how fire affects these mechanisms are reviewed. Sucker densities following fire and the influence of fire severity and intensity on sucker response are discussed. Understory response to fire and grazing is summarized from the literature. Appropriate land management and fire objectives are suggested for maintaining the aspen forest. A vegetation-fuel classification is described that recognizes three classes where aspen dominates: aspen-shrub, aspen-tall forb, and aspen-low forb. Two classes are recognized in mixed conifer-aspen forests: mixed-shrub and mixed- forb. Fuel loadings, fire intensities, and probabilities of successful prescribed fire are described. The aspen-shrub class is the most flammable and aspen-low forb and mixed-forb classes are the least flammable. Flammability is altered by slope, grazing intensity, curing of herbaceous vegetation, quantities of downed wood material, crown closure, and pocket gopher activity. Methods of predicting and estimating live fuel moisture contents are described.
Brown, J. K. and DeByle, N. V. 1989. Effects of Prescribed Fire on Biomass and Plant Succession in Western Aspen. Research Paper INT-412. Ogden, UT: U.S. Department of Agriculture Forest Service.
Abstract: Plant succession and production of biomass were determined for three prescribed fires in aspen (Populus tremuloides) and aspen-conifer forests. Forbs and shrubs dominated the understories. Preburn fuel loadings ranged from 19,200 to 56,400 kg/ha. Fires ranged from low to high severity and overstory mortality from 20 to 100 percent. Total fuel consumption alone was poorly related to fire severity. Over 4 postburn years, production of grasses and forbs averaged 1.5 to 3.3 times that of the controls. Maximum production was 2,240 kg/ha, five times that of the associated control. High-severity fire favored forbs over grasses. After 5 years, shrub biomass was 21 to 100 percent of preburn biomass. The proportion of shrub biomass less than 0.5cm diameter peaked after 2 years. Species responses were varied. Aspen sucker densities peaked during the fist 2 postburn years and ranged from one-half to fivefold their preburn densities. Suckering was most prolific following fire of moderate to high severity. The varied patterns of seral vegetation and their management implications are discussed.
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Brown, T. C. and Binkley, D. 1994. Effect of Management on Water Quality in North American Forests. Fort Collins, CO: U.S. Department of Agriculture Forest Service.
Abstract: Although the quality of water draining forested watersheds is typically the best in the Nation, some forest management practices can seriously impair streamwater quality. Sediment is the main concern. High suspended sediment levels, and adverse changes in stream channels, are potential problems in several regions, especially after road construction, and some harvesting and grazing practices. Impacts are most serious where fish reproduction is affected. Nitrate and water temperature are less serious problems. Harvesting can increase nitrate levels markedly, in some locations; and removal of overstory from along streambanks can raise water temperatures enough to impair fish survival. Best management practices (BMPs) can avoid most of these harmful effects. Additional work is needed, in some locations, to encourage BMP use and to tailor BMP specifications to site-specific conditions.
Burton, T. A., Dether, D. M., Erickson, J. R., et al. 1999. A Fire-Based Hazard/Risk Assessment. Fire Management Notes 59 No. 2: 31-36.
Abstract: In the Boise National Forest, wildfires in ponderosa pine forest have been increasingly large and severe since 1986. To respond to the threat to the forest's ponderosa pine ecosystem, a forest interdisciplinary team, working in partnership with the University of Idaho, developed a hazard/risk assessment using a geographic information system (GIS). This paper provides a description of the assessment, the methodology used to develop it, and the results of the analysis.
Busch, D. E. 1993. Fire in Southwestern Riparian Habitats: Functional and Community Responses. In Sustainable Ecological Systems: Implementing an Ecological Approach to Land Management. Fort Collins, CO: U.S. Department of Agriculture Forest Service.
Summary: A study of how fire affected riparian ecosystem processes in the lower Colorado and Bill Williams River floodplains. The study reports on both the functional responses (e.g., soil properties, leaf nitrogen concentrations) and community responses (e.g., relative cover and frequency of various species) of over 11,000 hectares of riparian vegetation subject to 166 fires between 1981 and 1992.
Busch, D. E. and Smith, S. D. 1993. Effects of Fire on Water and Salinity Relations of Riparian Woody Taxa. Oecologia 94: 186-194.
Abstract: Water and salinity relations were evaluated in recovering burned individuals of the dominant woody taxa from low-elevation riparian plant communities of the southwestern U.S. Soil elemental analyses indicated that concentrations of most nutrients increased following fire, contributing to a potential nutrient abundance but also elevated alluvium salinity. Boron, to which naturalized Tamarix ramosissima is tolerant, was also elevated in soils following fire. Lower
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moisture in the upper 30 cm of burned site soil profiles was attributed to shifts in evaportranspiration following fire. Higher leaf stomatal conductance occurred in all taxa on burned sites. This is apparently due to higher photosynthetic photon flux density at the midcanopy level and may be partially mitigated by reduced unit growth in resprouting burned individuals. Predawn water potentials varied little among sites, as was expected for plants exhibiting largely phreatophytic water uptake. Midday water potentials in recovering Salix gooddingii growing in the Colorado River floodplain reached levels which are considered stressful. Decreased hydraulic efficiency was also indicated for this species by examining transpiration water potential regressions. Recovering burned Tamarix and Tessaria sericea had enriched leaf tissue S13C relative to unburned controls. Higher water used efficiency following fire in these taxa may be attributed to halophytic adaptations, and to elevated foliar nitrogen in Tessaria. Consequently, mechanisms are proposed which would facilitate increased community dominance of Tamarix and Tessaria in association with fire. The theory that whole ecosystem processes are altered by invading species may thus be extended to include those processes related to disturbance.
Camp, A., Oliver, C., Hessburg, P., et al. 1997. Predicting Late-Successional Fire Refugia Pre-Dating European Settlement in the Wenatchee Mountains. Forest Ecology and Management 95: 63-77.
Abstract: Fires occur frequently in dry forests of the Inland West. Fire effects vary across the landscape, reflecting topography, elevation, aspect, slope, soils, and vegetation attributes. Patches minimally affected by successive fires may be thought of as 'refugia', islands of older forest in a younger forest matrix. Refugia support species absent within the landscape matrix. Our goal was to predict the occurrence of pre-settlement refugia using physiographic and topographic variables.
We evaluated 487 plots across a 47,000 ha landscape using three criteria to identify historical fire refugia: different structure from surrounding matrix; different fire regime from surrounding matrix; presence of old individuals of fire-intolerant tree species. Several combinations of aspect, elevation, and topography best predicted refugial presence.
Less than 20 percent of the pre-settlement landscape was identified as historical fire refugia. Refugia were not connected except by younger stands within the matrix. Current management goals of increasing amounts and connectivity of old, refugia- like and catastrophic wildfires.
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Campbell, A. G. 1987. Post-Fire Response of a Boulder-Bed Channel. In Erosion and Sedimentation in the Pacific Rim: Proceedings at the Corvallis Symposium Held at Oregon State University. Corvallis: International Association of Hydrological Sciences.
Summary: This study investigated the post-fire response of a boulder-bed channel in a 4 km2 portion of the Santa Ynez River drainage basin (34 29' N, 119 26' W) that burned in the Wheeler Fire of July 1985. Four representative channel reaches were selected for surveys during October 1985 and March 1986. The study found that while the general pattern of channel response was aggradation followed by degradation, the response at individual cross sections varied. The responses of the channel may have been related to changing erodibility of slopes that were actively recovering, variations in precipitation, and the distribution of boulders along the stream channel.
Caprio, A. C. and Swetnam, T. W. 1995. Historic Fire Regimes Along an Elevational Gradient on the West Slope of the Sierra Nevada, California. In Proceedings: Symposium on Fire in Wilderness and Park Management. Ogden, UT: U.S. Department of Agriculture Forest Service.
Summary: A study documenting fire occurrence patterns in the montane forest stands on the east slope of the Sierra Nevada for the last 300 to 400 years using dendrochronological analysis of tree-ring samples. This work is part of a larger research effort to understand and predict climate-related changes in ecosystems of the Sierra Nevada. Includes an analysis of the spatial and temporal fire patterns since 1700.
Chen, J., Franklin, J. F. and Spies, T. A. 1990. Microclimatic Pattern and Basic Biological Responses at the Clearcut Edges of Old-Growth Douglas-Fir Stands. Northwest Environmental Journal 6(2): 424-425.
Abstract: Microclimatic patterns and associated biological features have been under study along edges of mature and old-growth Douglas-fir (Pseudotsuga menziesii) fores in the Pacific Northwest since 1988. Preliminary results are presented here. This study has focused on forest edges adjacent to recent clearcuts. Edge exposure (orientation) is a primary variable. At each edge, portable weather stations and sampling plots are established at seven points along a transect extending from a clearcut to the interior (240 m) of the forest during summer and early fall. Temperature and moisture content of air and soil, wind speed, and short-wave radiation are monitored. Tree growth, regeneration, mortality, and stem distribution are measured on sample plots. Twenty different edges were studied during 1988 and 1989, in and around the H. J. Andrews (OR) and Wind River (WA) Experimental Forests.
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Cochran, P. H. and Barrett, J. W. 1999. Growth of Ponderosa Pine Thinned to Different Stocking Levels in Central Oregon: 30-Year Results. PNW-RP-508. Portland, OR: U.S. Department of Agriculture Forest Service.
Abstract: No mortality occurred at the lowest growing stock level (GSL) during any of the six 5-year periods of study. After the first period, plot mortality never exceeded two trees per acre for any 5-year period where stand density index values were below 240 at the start of the period. All mortality was attributed to mountain pine beetles (Dendroctonus ponderosae Hopkins). Pandora moth (Coloradia pandora Blake) caused partial defoliation during 1992 and 1994, which reduced growth rates in the last period (1991-95). Periodic annual increments for survivor quadratic mean diameters decreased curvilinearly with increasing GSLs, and the survivor height PAI-GSL relation varied with period. Gross volume and basal area PAI increased linearly with increasing GSLs. Gross basal area PAI and 30-year mean annual growth rates increased with increasing GSLs, but a significant curvilinear relation was not detected. Scribner board-foot yields at the stand age of 95 years increased linearly with increasing GSLs, while corresponding cubic-volume yields increased with increasing GSLs only if the initial thinnings were excluded. Mean annual increments (MAIs) for cubic volume increased with increasing stand age for all GSLs only if the initial thinning was excluded. Board-foot MAIs, with and without inclusion of initial thinning, increased with increasing stand age and with increasing GSLs. Mean annual growth of basal area and cubic volume for the 20 trees per acre with the largest diameters at the start of the study decreased curvilinearly with increasing GSLs. Increased periodic thinning levels greatly increased average tree size and reduced basal area and volume growth rates per acre.
Cornish, P. M. and Binns, D. 1987. Streamwater Quality Following Logging and Wildfire in a Dry Sclerophyll Forest in Southeastern Australia. Forest Ecology and Management 22: 1-28.
Abstract: In an 8-year study in two large adjacent forested river basins located in southeastern Australia, streamwater cationic composition was found to be greatly influenced by the minerology of the major lithology In each basin. While sodium was the dominant streamwater cation in each basin, it was relatively much higher in the Wallagaraugh basin in which the major bedrock contained considerably greater proportions of potash feldspar than in the Townamba basin. The chemistry of bulk precipitation, while similar in each basin, may have influenced the ultimate ionic composition of streamwater to a greater degree in the Towamba basin than in the Wallagaraugh basin.
Streamwater cationic concentrations in small sub-catchments subjected to logging and/or wildfire initially decreased relative to concentrations in an untreated control catchments in response to relative discharge increases, but became relatively greater than pre-wildfire 3-4 years later. Potassium concentrations in streamwater increased relative to the control in the year of the fire. Changes in the proportions of cations in streamwater in the small catchments during the study suggested that hydrologic
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changes resulting from a protracted drought, and from the logging and/or wildfire, may have influenced ionic release and ionic transport processes in these catchments. While these changes were readily detected in small catchments, they seem to have been largely buffered out in the major rivers.
Streamwater turbidity levels were increased in the year of logging by combinations of clearfall logging and wildfire in the small catchment study. Wildfire alone did not increase sampled turbidity levels. All burnt catchments, and especially those logged, experienced a reduction in sampled stream turbidity levels during the post-treatment period such that within 5 years the levels were significantly lower than those in unburnt, unlogged controls. These reductions are attributed to better catchments protection afforded by the dense revegetation of burnt areas which occurred during this period.
Turbidity levels in the logged research catchments were in general similar to those in major streams in the Wallagaraugh Valley whose catchments had also been subject to logging during the study period. Streams sampled in the nearby Towamba Valley, which experienced less logging in the period, had lower turbidity values throughout.
Everett, R., Lehmkuhl, J., Schellhaas, R., et al. 2002. Snag Dynamics in a Chronosequence of 26 Wildfires on the East Slope of the Cascade Range in Washington. Unpublished manuscript.
Abstract: Snag numbers and decay class were measured on a chronosequence of 26 Wildfires (ages 1 to 81 years) on the east slope of the Cascade Range in Washington. Snag longevity and resultant snag densities varied spatially across burns in relation to micro-topographic position. Longevity of snags <41cm dbh was greater for thin- barked Engelmann spruce (Picea engelmannii), subalpine fir (Abies lasiocarpa) and lodgepole pin (Pinus contorta) than thick-barked Douglas-fir (Pseudotsuga menziesii) and ponderosa pine (Pinus ponderosa). With larger diameter snags, however, Douglas-fir persisted longer than Englemann spruce. The time period required for recruitment of soft snags >23cm dbh was estimated to exceed snag longevity for ponderosa pine, Englemann spruce, lodgepole pine, and subalpine fir, causing an "on- site gap" in soft snags for these species. Snags of Douglas-fir >/=41cm dbh stood for a sufficient time (40 percent standing after 80 years) to potentially overlap the recruitment of soft snag greater than or equal to 23 cm dbh from the replacement stand. Providing continuity in soft snags following stand-replacement events would require a landscape-scale perspective, incorporating adjacent stands of different ages or disturbance histories. Results suggest that standards and guidelines for snags on public forest lands need to be sufficiently flexible to accommodate both disturbance and stand development phases and differences in snag longevity among species and topographic positions.
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Filip, G. M. and Goheen, D. J. 1995. Precommercial Thinning in Pseudotsuga, Tsuga, and Abies Stands Affected by Armillaria Root Disease: 10-Year Results. Can. J. For. Res. 25: 817-823.
Abstract: Four 10-to-20-year-old stands were precommercially thinned to determine the effects of thinning on tree growth and mortality caused by armillaria root disease in the Cascade Range of western Oregon and Washington, U.S.A: one stand of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. menziesii) and noble fir (Abies procera Rehd.). One of Douglas-fir and western hemlock (Tsuga heterophyila (Ref.) Sarg.), one of Douglas-fir alone, and one of Shasta red fir (Abies magnifica A. Murr. Var. shastensis Lemm.) and mountain hemlock (Tsuga meriensiana (bong.) Carr.). After 10 years, differences in crop-tree mortality between thinned and unthinned plots were not significant in any of the four stands. Tree radical growth was significantly increased by thinning in 6 of 15 plots. Crop-tree basal area (per hectare) growth was significantly greater in thinned plots. Basal area (per hectare) growth of all trees was significantly greater in unthinned plots. Apparently, from a root-disease perspective, precommerical thinning does not affect the incidence of corp-tree mortality after 10 years, but tree growth increases significantly.
Filip, G. M., Colbert, J. J., Parks, C. A., et al. 1989. Effects of Thinning on Volume Growth of Western Larch Infected with Dwarf Mistletoe in Northeastern Oregon. Western Journal of Applied Forestry 4(4): 143-145.
Abstract: Cubic volume growth and tree vigor of 70-year-old western larch (Larix occidentialis) with and without dwarf mistletoe (Arceuthobium laricis) were measured 15 years after thinning from above or below to residual densities of 50 to 170 ft2/ac. Vigor was assessed by cambial electrical resistance (CER). Proportional volume growth increased after thinning; was significantly related to the interaction of thinning method and residual density; and decreased with increased dwarf mistletoe severity. Thinning from above was associated with significantly higher proportional volume growth, but led to increased mortality from snow and ice damage to infected trees. CER was significantly related to severity of infection but not to treatment. Thinning is recommended in dwarf mistletoe infested stands of western larch to increase volume growth and reduce new infections in residual trees.
Filip, G. M. 1990. Effects of Tree Harvesting on Armillaria Root Disease in an Old-Growth Mixed-Conifer Stand in an Old-Growth Mixed-Conifer Stand in Northeastern Oregon. Northwest Environmental Journal 6(2): 412-413.
Summary: This study tests the hypothesis that root diseases cause severe mortality in white and grand fir stands of the Pacific Northwest. The study are is near La Grande, Oregon. The stand is composed of old-growth ponderosa pine (Pinus ponderosa), grand fir (Abies grandis), Douglas-fir (Pseudotsuga menziesii var. glauca), and western larch (Larix occidentalis). A portion of the stand is affected by Armillaria root disease (Armillaria ostoyae). This study is designed to examine disease spread and tree mortality over several decades.
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Grissino-Mayer, H. D. and Swetnam, T. W. 1995. Effects of Habitat Diversity on Fire Regimes in El Malpais National Monument, New Mexico. In Proceedings: Symposium on Fire in Wilderness and Park Management. Ogden, UT: U.S. Department of Agriculture Forest Service.
Summary: The purpose of this research was to: (1) determine the history of fire occurrence over the past 300 to 600 years in various habitat types using dendroecological techniques; (2) investigate spatial differences in fire regimes between sites, and propose possible historical and ecological explanations for these differences; (3) investigate temporal differences in fire occurrence within sites and propose possible explanations for these differences; (4) suggest preliminary recommendations for implementing a fire management policy that considers the complexity of the landscape and the historical perspective of human land-use patterns. Habitat types for this study are based on geologic characteristics, such as those used by Smathers and Mueller-Dombois (1974) for volcanic areas in Hawaii, rather than potential climax associations.
Halpern, C. B. 1989. Early Successional Patterns of Forest Species: Interactions of Life History Traits and Disturbance. Ecology 70(3): 704-720.
Abstract: Patterns of abundance were examined for vascular plant species during 21 yr of succession in two clear-cut and burned Psudotsuga forest in the western Cascade Range of Oregon. A majoirty of forest understory species persisted thorugh distrubances. Most colonizing species established within 2 yr after burning. Individualistic species responses were described by a series of broadly overlapping, unimodel curves of constancy and canopy cover, differing in time of initiation, duration, and magnitude. Thus, early successional change was characterized by gradual shifts in the abundance of generally persistent species.
Eleven population patters (species groups) were identifed. Interactions of life history traits and disturbance explain the temporall trends of the most common species. Within the groups of invading species, the timing of intial estabishment, as well as the timing and magnitude of peak abundance were related to the origin of propagules, phenological traits, potential for vegetative expansion, and temporal and spatial variations in disturbance. Abundance patterns of invading species were also influenced by stochastic and historical factors. Contracting responses of species between sites relfected differences in histories of logging and slash burning. Within the groups of resdual species, temporal patterns of abundance reflected initial species distrbution, resistance to logging and burning disturbance, mode of reproduction, morphological traits, and spaital variation in disturbance intensity.
These observations suggest that early secondary succession in Psudotsuga forests has a determinstic component, founded in the life history and traits of the available species, and a stochastic component reflecting site history and variation in disturbance.
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Harrod, R. J., Gaines, W. L., Hartl, W. E., et al. 1998. Estimating Historical Snag Density in Dry Forests East of the Cascade Range. PNW-GTR-428. Portland, OR: U.S. Department of Agriculture Forest Service.
Abstract: Estimating snag densities in pre-European settlement landscapes (I.e., histroical conditions) provides land managers with baseline information for comparing current snag densities. We propose a method for determining historical snag densities in the dry forest east of the Cascade Range. Basal area increase was calculated from tree ring measurements of old ponderosa pine (Pinus ponderosa Dougl. Ex Laws.) trees. Historical stand structure was assumed to be open and parklike, with low desities favoring larger diameter trees, and it was considered relatively stable at the landscape level. Snag density (S) was calculated by holding forest stand structure relatively constant (basal area range 13.8 to 18.4 square meters per hectare [60 to 80 ft2/acre] and diameter size class distributions with q-factors of 1.1 or 1.2), assuming snag recruitment could be no greater than annual basal area increase, and estimating that all snags fail by 45 years; S=(1+Eri), where a is annual recruitment and Eri is a sum of the ratios fo snags remaining from previous recruitment years (I). If eight represnetative snag sizes are selected, snag density in histroical landscapes ranged from 14.5 to 34.6 snags per hectare (5.9 to 14.1 snges per acre).
Hawksworth, F. G. and Johnson, D. W. 1989. Biology and Management of Dwarf Mistletoe in Lodgepole Pine in the Rocky Mountains. GTR-RM-169. Fort Collins, CO: U.S. Department of Agriculture Forest Service.
Abstract: This publication synthesizes the vast literature on lodgepole pine dwarf mistletoe (Arceuthobium americanum) and adds some new information on biology of the parasite. Although dwarf mistletoe has been recognized as a serious parasite of lodgepole pine for more than 75 years, its routine operational control through forest management has been primarily a development over the past two decades. This report discusses silvicultural control of dwarf mistletoe in various types of stands where fiber production is the primary goal, and also in forests used mainly for recreation.
Hessburg, P. F., Smith, B. G. and Salter, R. B. 1999. Detecting Change in Forest Spatial Patterns from Reference Conditions. Ecological Applications 9(4): 1232-1252.
Abstract: Timber harvest, fire suppression, road construction, and domestic livestock grazing have transformed spatial patterns of Interior Northwest forests. As a consequence, parameters of current disturbance regimes differ radically from historical regimes; present day wildlife habitat distributions differ from historical distributions; and long-term survival of some native terrestrial species is uncertain. Public land managers are under increasing scientific and social pressure to mold existing forest spatial patterns to reflect those resulting from natural disturbance regimes and patterns of biophysical environments. However, knowledge of the characteristics of natural spatial patterns is unavailable.
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Using a dichotomized ordination procedure, we grouped 343 forested subwatersheds (mean area, 8,000 ha) on the eastern slope of the Cascade Mountains in Washington State into ecological subregions by similarity of area in potential vegetation and climate attributes. We built spatially continuous "historical" (1938-1956) and "current" (1985-1993) vegetation maps for 48 randomly selected subwatersheds from aerial photo interpretations. From remotely sensed attributes, we classified cover types, structural classes, and potential vegetation types and attributed them to individual patches. We then estimated a reference variation (RV) in spatial patterns of patch types (cover type and structural class), by subwatersheds and five forested ecological subregions, using the 48 historical vegetation maps stratified by subregion and a spatial pattern analysis program. Finally, we compared the current pattern of an example subwatershed (MET_11) with the RV estimates of its corresponding subregion to illustrate how reference conditions can be used to evaluate the importance of spatial pattern change. By evaluating pattern changes in light of RV estimates (nominally, the sample median 80 percent range of a metric) and the full range of class and landscape metrics, we could identify both current and historical conditions of MET_11 that fell outside the RV. This approach gives land managers a tool to compare characteristics of present -day managed landscapes with reference conditions to reveal significant pattern departures, as well as to identify specific pattern characteristics that might be modified through management. It also provides a means to identify "outlier" conditions, relative to subregion RV estimates, that may occasionally be the object of pattern restoration activities.
Hibbs, D. E. and Bower, A. L. 2001. Riparian Forests in the Oregon Coast Range. Forest Ecology and Management 154: 201-213.
Abstract: We examined the structure and composition of forested buffer strips in the central and northern Coast Range of Oregon and found little botanical evidence of an effect on plant community composition or dynamics from isolating these forests as buffers. Thus, concerns about microenvironment changes due to extended edge effects appear unfounded in this region for the plant community. Tree stocking was low, especially on terraces; evidence suggests that competition, as well as site conditions, limit the regeneration of trees, including conifers. Understory diversity (richness) was greater under conifer canopy types; understory cover was greater under hardwood canopy types. Tree regeneration, especially on terrace and under hardwoods, was limited although more abundant than in older, unmanaged riparian forest. In the long term, succession models for this region suggest that many of these riparian areas will succeed to a largely treeless community.
Kaye, J. P. and Hart, S. C. 1998. Restoration and Canopy-Type Effects on Soil Respiration in a Ponderosa Pine-Bunchgrass Ecosystem. Soil Sci. Soc. Am. J. 62: 1062-1072.
Abstract: In ponderosa pine (Pinus ponderosa Douglas ex. P. Lawson & Lawson)- bunchgrass ecosystems of the western USA, fire exclusion by Euro-American settlers facilitated pine invasion of grassy openings, increased forest floor detritus, and shifted the disturbance regime toward stand-replacing fires, motivating ecological
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restoration through thinning and prescribed burning. We used in situ soil respiration over 2-yr period to assess belowground responses to pine invasion and restoration in ponderosa pine-bunchgrass ecosystem near Flagstaff, AZ. Replicated restoration treatments were: (I) partial restoration-- thinning to presettlement conditions; (ii) complete restoration--removing trees and forest floor material to presettlement conditions, native grass litter addition, and prescribed burnings; and (iii) control. Within treatments, we sampled beneath different canopy types to asses the effects of pine invasion into grassy openings on soil respiration. Growing season soil respiration was greater in the complete restoration (346+24 g CO2-Cm-2) and control (350+8g CO2-Cm-2) than the partial restoration (301+5g CO2-Cm-2) in 1995. In 1996, the complete (364+17g CO2-Cm-2) and partial (328+7g CO2-Cm-2) restoration treatments had greater growing season respiration rates than the control (308+13g CO2-C m-2). Results suggest that restoration effects on soil respiration depends on interannual soil water patterns and may not significantly alter regional C cycles. Soil respiration form grassy openings was 15 percent greater than form soil beneath presettlement or postsettlement pines in 1995 and 1996. A lack of active management will decrease belowground catabolism if pines continue to expand at the expense of grassy openings.
Klenner, W., Kurz, W. and Beukema, S. 2000. Habitat Patterns in Forested Landscapes: Management Practices and the Uncertainty Associated with Natural Disturbances. Computers and Electronics in Agriculture 27: 243-262.
Abstract: We present the results of a study to examine the effects of management actions and natural disturbances in influencing the evolution of habitat patterns on forested lands. TELSA, a spatially explicit vegetation succession model with the ability to apply user-defined management actions and stochastic wildfires calibrated to local conditions, was used to evaluated changes in several indicators of habitat condition. We assessed seral stage and patch size changes over multiple 200-year simulations under constant rate of harvest within each of these analyses. In the absence of natural disturbances, old growth habitat and large patches of forest of similar age and tree species composition decreased unless special management practices were applied. Old-growth management area reserves and periodic 'aggregated cutblock' harvesting entries helped maintain forest seral stage distribution at the target level, and patch size characteristics similar to the patterns that would have occurred under historic natural disturbances. Adding wildfire to the management scenarios substantially reduced the amount of old growth habitat in designated old-growth management area reserves, compromising the ability to maintain old-growth at target levels. Fifty percent increase in the area designated as old-growth management area reserves would be required to off-set the loss of old growth due to wildfire. Although the amount of old-growth habitat was diminished by wildfire, the availability of large habitat patches greater than 250 ha increased. We discuss the need to consider the role of management and natural disturbances in landscape planning, and suggest that redundancy is essential to maintain those features vulnerable to stochastic disturbances. Landscape scenario modeling can
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facilitate the development of risk averse plans, and encourage the development of innovative approaches to achieving timber and non-timber objectives.
Kurz, W. A. and Apps, M. J. 1999. A 70-Year Retrospective Analysis of Carbon Fluxes in the Canadian Forest Sector. Ecological Applications 9(2): 526-547.
Abstract: The Carbon Budget Model of the Canadian Forest Sector (CBM-CFS2) is a framework for the dynamic accounting of carbon pools and fluxes in Canada's forest ecosystems and the forest product sector. The model structure, assumptions, and supporting databases are described. The model has been applied to estimate net ecosystem carbon fluxes for Canada's 404 Mha forest area for the period of 1920- 1989. Changes in disturbance regimes have affected the forest age class structure and increased the average forest age during the period 1920-1979. The resulting changes in dead organic matter and biomass carbon during this period were estimated with the model. In the last decade of the analysis, large increases in disturbances, primarily fire and insect damage have resulted in a reduction in ecosystem carbon storage. The estimates of biomass pool sizes obtained are consistent with those of other studies, while dead organic matter carbon pool estimates remain somewhat uncertain. Sensitivity analysis of several sources of uncertainty indicate that the pattern of net changes in ecosystem carbon pools of the 70-yr. period was hardly affected and that the numerical estimates change by less than 15 percent.
Lehmkuhl, J. F., Hessburg, P. F., Everett, R. L., et al. 1994. Historical and Current Forest Landscapes of Eastern Oregon and Washington. Part I: Vegetation Pattern and Insect and Disease Hazards. PNW-GTR-328. Portland, OR: U.S. Department of Agriculture Forest Service.
Abstract: We analyzed historical and current vegetation composition and structure in 49 sample watersheds, primarily on National Forests, within six river basins in eastern Oregon and Washington. Vegetation patterns were mapped from aerial photographs taken from 1932 to 1959, and from 1985 to 1992. We described vegetation attributes, landscape patterns, the range of historical variability, scales of change, and distrubance hazards. Forest cover increase eight percent in three river basins, but remained relatively unchanged in the other basins. Forests became more dense in vertical and horizontal canopy structure as understory cover increase with regeneration of mostly shade-tolerant species. The distribution of forest age classes and structure has changed, with smaller area in early-seral and old forest stages and greater area in multiple-canopy young and mature stands. The percentage of visible dead trees increased in all river basins. Landscape pattern has become more diverse and fragmented over time in five of the six river basins. Insect and disease hazards changed little, usually <10 percent, at the river basin scale because there was considerable variation at the watershed scale, where large changes in hazards were common.
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Little, R. L., Peterson, D. L., Silsbee, D. G., et al. 1995. Radial Growth Patterns and the Effects of Climate on Second-Growth Douglas-Fir (Pseudotsuga menziesii) in the Siskiyou Mountains, Oregon. Can. J. For. Res. 25: 724-735.
Abstract: The sites with fire-generated second-growth (70-100 years old) Douglas- fir (Pseudotsuga menziesii (Mirb.) Franco) in southwestern Oregon were examined using dendroecological techniques to determine (1) temporal patterns of radial growth and (2) the effects of variation in climate on growth. Long-term patterns of radial growth vary among sites, but similar interannual variation in radial growth indicates a common response to regional climate. Growth is positively correlated with the Palmer Drought Severity Index and precipitation during summer. Furthermore, growth is positively correlated with precipitation during autumn prior to the growth year, which suggests the benefits of soil moisture recharge for subsequent stemwood production. Annual precipitation is strongly seasonal, and soil moisture stress in summer is apparently severe enough to be the dominant climatic influence on radial growth. Positive correlations of growth with most monthly temperatures reflect the benefit of warm temperatures on photosynthesis and radial growth during periods of adequate soil moisture. Although coastal Oregon is generally considered to be a high precipitation environment, conditions are clearly dry enough during summer to limit carbon gain in second-growth Douglas-fir. If future climatic conditions result in increased soil moisture stress during summer, productivity of such second-growth stands may decrease below current levels.
Lynch, A. M. and Swetnam, T. W. 1992. Old-Growth Mixed-Conifer and Western Spruce Budworm in the Southern Rocky Mountains. In Old Growth Forests in the Southwest and Rocky Mountain Regions, Proceedings of a Workshop (GTR RM-213). Arizona: U.S. Department of Agriculture Forest Service.
Abstract: Thirty-one mixed-conifer stands 98 to 694 years old in the southern Rocky Mountains revealed a history of multiple western spruce budworm outbreaks. Outbreaks were neither more nor less frequent in older stands, nor did outbreaks appear to start in older stands. Western spruce budworm does not appear to direcly threaten old growth stands, but management policies that repress natural disturbance regimes and promote budworm-prone forests may result in remnant old growth stands being less likely to survive severe insect outbreaks and potential catstrophic wildfires. Outbreaks may persist longer in older stands, but data from different areas and age groups are inconsistent. The appearance and structure of some stands are different from common preceptions of old growth mixed-conifer. Decadence and dead standing and down trees are probably not useful indicators of old growth in forest types subject to periodic mortality causing insect outbreaks. Two exceptionally old stands in New Mexico, 494 and 694 years old, have tree densites exceeding 1000 trees per ha, have old trees smaller in size than the main canopy trees, and had fewer outbreaks in the last 120 years than most of the stands sampled in northern New Mexico.
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McDonald, G. I., Martin, N. E. and Harvey, A. E. 1987. Armillaria in the Northern Rockies: Pathogenicity and Host Susceptibility on Pristine and Disturbed Sites. Research Note INT-371. Ogden, UT: U.S. Department of Agriculture Forest Service.
Abstract: Over all plots (disturbed and pristine), incidence of pathogenic Armillaria showed a strong tendency to decrease as habitat type productivity increased. This trend gave rise to a clear separation of plots by climax series. The relatively less productive subalpine fir and Douglas-fir series exhibited high incidence of root disease and the relatively more productive grand fir, western red cedar, and western hemlock series significantly less. Within these productivity groups, other patterns emerged. Disturbance appeared to be related to a dramatic increase in incidence of pathogenicity, but not occurrence, within the high-productivity grouping of communities. Also, the ability of disturbance to elicit pathogenicity seemed to decline as site productivity increased. Conversely, the pristine plots within the low- productivity series exhibited high incidence of the pathogen in a pathogenic state. This condition seemed to be related to a community structure characteristic of transition between cold-dry to cool-moist and warm-dry to warm-moist. Predicting risk of Armillaria-caused mortality, occurrence of pathogenic species and clones of Armillaria, a possible role for host stress in expression of pathogenicity by Armillaria, and risk rating of host species are discussed.
Miles, D. W. R., Swanson, F. J., Youngberg, C. T. 1984. Effects of Landslide Erosion on Subsequent Douglas-Fir Growth and Stocking Levels in the Western Cascades, Oregon. Soil Sci. Soc. Am. J. 48: 667-671.
Abstract: Shallow, rapid landslides are common events in steep terrain of the Pacific Northwest. The effect of landslides on timber growth potential of forest land was estimated by examining a 30-yr history of clearcutting and landslidings in the western Oregon Cascades. The height growth of Douglas-firs [Psendors? Menziesii (Mirb) Franco] and stocking level of all commercial conifer species on naturally regenerated landslides were compared with the height growth and stocking level in nearby, artificially regenerated clearcut units of similar aspect, elevation, age, and slope position. Average height growth of Douglas-fir trees 5 to 18 years old on the landslides was reduced 62 percent compared to trees on clearcuts, and the average stocking level was reduced 25 percent from the clearcut level. One-third of the landslide area was estimated to be nonstockable because of unstable or impenetrable substrate.
Mitchell, R. G. and Preisler, H. K. 1991. Analysis of Spatial Patterns of Lodgepole Pine Attacked by Outbreak Populations of the Mountain Pine Beetle. Forest Science 37(5): 1390-1408.
Abstract: Five years of moutain pine beetle, Dendroctonus ponderosae Hopkins, attacks on lodgepole pine, Pinus contorta Dougl., were analyzed in an early outbreak situation using generalized linear models to shed light on patterns in the colonization process. The chosen logit model indicated three covariates as significant factors in
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the probability of trees being colonized by the mountain pine beetle. The first covariate related to tree size and spatial relationships among trees cononized the same year; its effect was most obvious for trees in the smaller diameter classes. The other two covariates correlated with tree diameters and vigor, and they indicated a greater probability of attack for larger trees and trees with low vigor. The model showed that the probability of trees being colonized in this stand increased significantly as the outbreak gained momentum, but only as long as the food supply (trees with dbh>23cm) was abundant. It also showed that the pattern of selection of large and small trees did not change significantly as beetle pressure increased over time. Findings suggested that big trees were important to outbreaks beyond simply generating beetles, and that many trees were colonized only because they were close to other trees under attack.
Mitchell, R. G., Waring, R. H. and Pitman, G. B. 1983. Thinning Lodgepole Pine Increases Tree Vigor and Resistance to Mountain Pine Beetle. Forest Science 29(1): 204-211.
Abstract: Thinned and unthinned stands of lodgpole pine in eastern Oregon were evaluted in 1980 to determine their vigor and susceptibility to attack by outbreak populations of the mountain pine beetle. Application of a vigor rating system, based on amount of stem grwoth per square meter of crown leaf area, showed that thinnings from below improved vigor of residual stand and reduced beetle attack. Beetle mortality was signifcant in unthinned and lightly thinned stands where current annaul growth of stemwood of residual trees averaged less than 80 percent g/m of foliage. Stands with mean vigor ratings of about 100 were beginning to suffer beetle attack. There was no mortality in heavily thinned stands where vigor ratings exceeded 120. These findings suggest that lodgepole pin can be managed through stocking control to obtain fast-growing, large diameter trees and to avoid attack by the mountain pine beetle.
Morgan, P. and Parsons, R. 1998. Historical Range of Variability for the Idaho Southern Batholith Ecosystem. Unpublished manuscript, University of Idaho, Department of Forest Resources, Boise, ID.
Abstract: Describing historical conditions is part of a course-filter management strategy for sustaining biological diversity. It provides a context for interpreting natural processes, especially disturbance, and it allows variability in patterns and processes to be understood in terms of a dynamic system. The overall goal of this project was to estimate the historical range of variability for the forests of the Idaho Southern Batholith. This area encompasses approximately 5.8 million acres in central Idaho, from dry ponderosa pine to high elevation subalpine fir. We used successional models parameterized by expert opinion and available data to estimate the minimum, maximum, and median abundance (percent of potential area occupied) for elements in the ecosystem diversity matrix. These elements are combinations of vegetation growth stage (VGS, a description of tree size and canopy layering) and dominant cover type (forest vegetation named for the species occupying the majority of the
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stand) for each of eleven habitat type classifications (these represent groups of similar biophysical descriptions).
North, M. and Franklin, J. 1990. Post-Disturbance Legacies that Enhance Biological Diversity in a Pacific Northwest Old-Growth Forest. Northwest Environmental Journal 6(2): 427-429.
Summary: The importance of the structure-function relationship is demonstrated by two recent spotted owl surveys which located nesting owl pairs in stands that were heavily disturbed by a windstorm near Forks, Washington, and a fire in the Quilcene area of the Olympic Peninsula. Our objective is to quantify structure in these stands to determine how disturbed forests may soon re-establish the function and composition of an old-growth ecosystem.
Reid, L. M. and Hilton, S. 1998. Buffering the Buffer. In Proceedings of the Conference on Coastal Watersheds: The Caspar Creek Story (PSW-GTR-168). Albany, CA: U.S. Department of Agriculture Forest Service.
Abstract: Riparian buffer strips are a widely accepted tool for helping to sustain aquatic ecosystems and to protect downstream resources and values in forested areas, but controversy persists over how wide a buffer strip is necessary. The physical integrity of stream channels is expected to be sustained if the characteristics and rates of tree fall along buffered reaches are similar to those in undisturbed forests. Although most tree-fall-related sediment and woody debris inputs to Caspar Creek are generated by trees falling from within a tree's height of the channel, about 30 percent of those tree falls are triggered by trees falling from upslope of the contributing tree, suggesting that the core zone over which natural rates of tree fall would need to be sustained is wider than the one-tree-height's-width previously assumed. Furthermore, an additional width of "fringe" buffer is necessary to sustain appropriate tree-fall rates within the core buffer. Analysis of the distribution of tree falls in buffer strips and un-reentered stream-side forests along the North Fork of Caspar Creek suggests that rates of tree fall are abnormally high for a distance of at least 200m from a clearcut edge, a distance equivalent to nearly four times the current canopy height. The appropriate width of fringe buffer needed to protect the core zone will need to be determined using an analysis of the long-term effects and signficance of accelerated tree-fall rates after logging.
Rot, B. W. 1995. The Interaction of Valley Constraint, Riparian Landform, and Riparian Plant Community Size and Age Upon Channel Configuration of Small Streams of the Western Cascade Mountains, Washington. Ph.D. diss., University of Washington, College of Forest Resources.
Abstract: Biophysical factors influencing channel configuration were measured for 21 sites in mature to old forests of the western Cascades Mountains, Washington. The overall goal was to understand the patterns between channel configuration, valley constraint, riparian landform, channel type, and the riparian plant community size and
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age. Valley constraint was described in terms of the ratio of valley width to channel width. Riparian landform was delineated into four classes, three fluvially derived and organized by elevation above the channel, with the fourth class, slope, originating from non-fluvial processes. The three fluvial landforms were: floodplain (<1 m), low terrace (1-3m), high terrace (>3 m); with the fourth class, slope (>20 percent gradient and >15 m in width). The riparian plant community was characterized by the overstory species composition, density, and stand age, and understory species composition and precent cover. Stream channels were classified using a conceptual mode based upon their expected response to changes in sediment supply and discharge.
Both successional processes and fluvial distrubances control riparian plant community composition based upon landform class. Floodplain landforms are dominated by deciduous species, especially red alder (62 percent of stems), while conifers dominated the other landforms. Conifers are found on low terrace landforms, specifically Pacific silver fir (Abies amabilis) and western hemlock (Tsuga heterophylla, 77 percent of stems). High terrace landforms support Douglas-fir (Pseudotsuga menziesii) and western hemlock (72 percent of stems), while slope landforms supported mostly western hemlock and some Douglas-fir (73 percent of stems). In addition, the relative importance of Douglas fir decreased with stand age for the three coniferous landforms indicating the effects of successional processes.
Valley constraint significantly influenced LWD volume within forced pool-riffle channels with the volume increasing as a power function of decreasing valley constraint (r2=0.58). No relationship was found with the other channel types. The presence of off-channel habiat for aquatic organisms increased exponentially with decreasing valley constraint for all channel types (r2=0.71).
Within the stream channel, the diameter of LWD was related to the age of the riparian forest. In old growth stands (>300 yrs), LWD diameter was great than average riparian forest diameter for all sites. A mixed relationship between LWD and riparian forest diameter in younger stands reflected a mixture of LWD from previous stands, smaller suppressed stems from existing stands, and a wide range of diameters contributed by bank erosion. Finally, LWD diameter increased overall with stand age (r2=0.34).
This study was important for several reasons. First, it correlated fish habitat (channel configuration) to biophysical factors across multiple temporal and spatial scales. Second, the importance of successional processes within the riparian forest to channel configuration was also discussed. Finally, the composition of the riparian plant community was related to riparian landform. As a whole, the results suggest that the creation and maintenance of fish habitat results from the complex interaction of a variety of biophysical factors.
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Schoonmaker, P. and McKee, A. 1988. Species Composition and Diversity During Secondary Succession of Coniferous Forests in the Western Cascade Mountains of Oregon. Forest Science 34(4): 960-979.
Abstract: Species diversity and community composition were studied at 23 sites on similar western hemlock/Douglas-fir forest habitats, in undisturbed old-growth stands and stands at 2, 5, 10, 15, 20, 30 and 40 years after clearcutting, broadcast burning, and planting with Douglas-fir. Vegetation was sampled with three 5x60m transects at each site. Invading herbs, then invading and residual shrubs, and finally conifers dominated through the first 30 years. Late seral species, which account for 99 percent of cover in old-growth stands, are nearly eliminated immediately following disturbance, but account for almost 40 percent of vegetative cover after 5 years, 66 percent after 10 years, 83 percent after 20 years, and 97 percent after 40 years. After an initial drop following disturbance, species diversity trends weakly upward with heterogeneity peaking at 15 years and richness at 20 years. This initially high diversity (higher than that of old-growth stands ) is short-lived. After the tree canopy closes, species diversity declines reaching its lowest values at 40 years. Only two species were eradicated after disturbance, both mycotophs. Pacific Northwest old- growth forests are relatively poor in species, but moderately high in heterogeneity values.
Speer, J. H., Swetnam, T. W., Wickman, B. E., et al. 2001. Changes in Pandora Moth Outbreak Dynamics During the Past 622 Years. Ecology 82(3): 679-697.
Abstract: Episodic outbreaks of pandora moth (Coloradia pandora Blake), a forest insect that defoliates ponderosa pine (Pinus ponderosa Dougl. Ex Laws.) and other pine species in the western United States, have recurred several times during the 20th century in forests of south-central Oregon. We collected and analyzed tree-ring samples from stands affected by recent outbreaks of pandora moth to develop a long- term record of outbreaks. Outbreaks were evident in tree-ring series as a characteristic "signature" of sharply reduced latewood width within a ring, followed by reduced ring widths lasting 4-20 yr. We verified that this tree-ring signature was unrelated to drought or other climatic fluctuations by comparing the timing of known and inferred outbreaks with independent climatic data. Using the pandora moth tree- ring signature, we reconstructed a 622-year record of 22 individual outbreaks in 14 old-growth ponderosa pine stands. This is currently the longest regional reconstruction of forest insect outbreak in North America. Intervals between pandora moth outbreaks were highly variable within individual forest stands, ranging from 9 yr to 156 yr. Spectral analyses of a composite time series from all stands, however, showed more consistent intervals between outbreaks, suggesting quaicyclical population dynamics at regional and decadal scales. Wavefoms extracted from the regional outbreak time series had periods ranging over 18-24 yr (39.7 percent variance explained) and 37-41 yr (37.3 percent variance explained). The periods and strengths of these cycles varied across the centuries, with the largest outbreaks occurring when relatively high-amplitude periods of the dominant cycles were in phase. Twentieth-century outbreaks were not more synchronous (extensive), severe,
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or longer in duration than outbreaks in previous centuries, but there was an unusual 60- yr reduction in regional activity during 1920-1980. The changing dynamical behavior of pandora moth populations highlights the need to evaluate historical factors that may have influenced this system, such as climatic variations, forest fires, and human land uses. Although cyclical dynamics in animal populations have most commonly been attributed to endogenous, ecological processes (e.g., “delayed density dependence,” predators, pathogens, and parasites) our findings suggest that exogenous processes (e.g., climatic oscillations) may also be involved.
Suzuki, W., Osumi, K., Masaki, T., et al. 2002. Disturbance Regimes and Community Structures of a Riparian and an Adjacent Terrace Stand in the Kanumazawa Riparian Research Forest, Northern Japan. Forest Ecology and Management 157: 285-301.
Abstract: Riparian forests and adjacent upland forests often exhibit differences in composition and diversity. This variation should be due in part to difference in site condition and in part to difference in disturbance regime. To understand relative roles of these differences, structure, composition and diversity were compared between a riparian forest and an adjacent terrace forest through analyzing topography-specific guild structure referring to disturbance regime in an old-growth temperate deciduous forest in northern Japan.
The study plot (4.71ha) was topographically divided into four units: a riparian area (RP) and a terrace (TR) as major parts, and a colluvial slope (CS) and a denuded slope (DS) as minor parts. The riparian area included various microsites, such as an active channel, and lower and higher floodplains, which have been formed by multiple types of natural disturbances: flooding debris flow and tree-fall. In contrast, in the terrace, only tree-falls were the prevailing disturbance and homogeneous site conditions (a gentle slope and deep organic soil) developed. In the riparian area, a species-rich stand with higher diversity indices (e.g. equitability), mainly composed of Cercidiphyllum japonicum, Aesculus turbinata and Pterocarya rhoifolia, developed. In contrast, the terrace stand was dominated by a single species, Fagus crenata, and showed lower species richness and diversity. Three topography-specific guilds (RP-type, nine species; TR-type, eleven species; DS-type, three species) and one guild of generalist (five species) were found. Other 13 species were infrequent. The higher species richness and equitability in the riparian stands were attributed to the facts that the riparian stands include many species of non-riparian-specific guilds and many infrequent species as well as RP-type species, and that the terrace stand, in contrast, were mainly composed of TR-type species and a few generalists. In the riparian area heterogeneous site condition created by multiple disturbance regimes allowed species with different niche to coexist. In addition, there was some evidence in the riparian area that the geomorphic processes with infrequent and large-scale disturbances formed mosaics of various successional stages, suggesting a non- equilibrium species coexistence in the riparian community.
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Taylor, A. H. and Solem, M. N. 2001. Fire Regimes and Stand Dynamics in an Upper Montane Forest Landscape in the Southern Cascades, Caribou Wilderness, California. Journal of the Torrey Botanical Society 128(4): 350-361.
Abstract: Fire is the most frequent and widespread disturbance affecting forests in the Pacific Northwest and identifying the frequency, extent, and severity of fires is essential for understanding the role of fire in longterm forest dynamics. This study quantifies presettlement fire regimes (i.e. fire return interval, fire extent, fire severity, fire rotation) and successional patterns in a 950 ha upper motane forest using 39 cross-dated fire scar samples, tree ages and radial growth patterns in cores, and tree diameters distributions in 112 plots. Forest species composition varied with potential soil moisture and there was variation in some fire regime parameters among forest compositional groups. Mean fire return intervals were shortest in red fir-white fir forests (41 yr), and longer in white fir-Jeffrey pine, lodgepole pine, lodgepole pin-red fir, and red fir-western white pine forests (59-70 yr). Lodgepole pine and lodgepole pine-redfir forests experienced more high severity (38 to 75 percent) fire than other forest types (13 to 25 percent). Fire rotation varied by time period, and wash shortest in the pre-Euro-American period (76 yr), longer in the settlement period (177 yr), and longest in the fire suppression (577 yr) period. The average extent of a fire was small (150 ha). Lodgepole pine-red fir, white fir-Jeffrey pine, and red fir-white fir forest are changing in composition but lodgepole pine and red fir-western white pin forests are compositionally stable. Recurring fire in the presettlement period maintained fire- dependent pines but fire suppression is now causing shifts in species composition and changes in landscape scale vegetation patterns similar to those in lower montane forests.
Thomson, A. J. and Shrimpton, D. M. 1984. Weather Associated with the Start of Mountain Pine Beetle Outbreaks. Can. J. For. Res. 14: 255-258.
Abstract: Extreme weather conditions associated with mountain pine beetle outbreaks were evaluated by graphical techniques for six locations throughout British Columbia. Three major associations of extreme weather patterns with lodgepole pine growth and mountain pine beetle outbreaks were identified. (I) Weather effects prior to, or early in, the growing season can reduce growth without releasing the beetle population. (ii) Weather conducive to beetle establishment and early brood development can occur too late in the season to have a noticeable effect on tree growth and therefore will not be recorded in the annual growth rings. (iii) Warm, dry periods during the summer are associated with tree growth reduction and the beginnings of outbreaks. In each of these three cases, extreme low precipitation levels were involved. Average precipitation in some months did not compensate for the effects of unfavourable extremes in other months on tree growth.
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Thomson, A. J., Shepherd, R.F., Harris, J. W. E., et al. 1984. Relating Weather to Outbreaks of Western Spruce Budworm, Choristoneura occidentalis (Lepidoptera: Tortricidae), in British Columbia. The Canadian Entomologist 116: 375-381.
Abstract: The relationship of western spruce budworm outbreaks and population collapse to weather parameters was examined using long term weather records from two stations in the budworm outbreak area of British Columbia and outbreak patterns obtained from Forest Insect and Disease Survey records and from tree stem analyses.
Out breaks were associated with warm dry summers in conjunction with synchrony of larval emergence and bud flush. Collapse of the last two outbreaks was clearly associated with extreme high temperatures following moth flight. Collapse of the earlier outbreaks may have been due to asynchrony between larval emergence and bud flush.
Touchan, R., Allen, C. D. and Swetnam, T. W. 1996. Fire History and Climatic Patterns in Ponderosa Pine and Mixed-Conifer Forests of the Jemez Mountains, Northern New Mexico. In Fire Effects in Southwestern Forests: Proceedings of the Second La Mesa Fire Symposium. Edited by Allen, C. D. Fort Collins, CO: U.S. Department of Agriculture Forest Service.
Abstract: We constructed fire history in ponderosa pine and mixed conifer forests across the Jemez Mountains in northern New Mexico. We collected fire-scarred samples from ten ponderosa pine areas, and three mesic mixed-conifer areas. Prior to 1900, ponderosa pine forests were characterized by high frequency, low intensity surface fire regimes. The mixed-conifer stands sustained somewhat less frequent surface fires, along with patchy crown fires. We also examined the associations between past fires and winter-spring precipitation. In both ponderosa pine and mixed-conifer forests, precipitation was significantly reduced in the winter-spring period immediately prior to fire occurrence. In addition, winter-spring precipitation during the second year preceding major fire years in the ponderosa pine forest was significantly increase. The results of this study provide baseline knowledge concerning the ecological role of fire in ponderosa pine and mixed-conifer forests. This information is vital to support ongoing ecosystem management efforts in the Jemez Mountains.
Townsend, C. R., Scarsbrook, M. R.and Doledec, S. 1997. The Intermediate Disturbance Hypothesis, Refugia, and Biodiversity in Streams. Limnol. Oceanogr. 42(5): 938- 949.
Abstract: The intermediate disturbance hypothesis has been influential in the development of ecological theory and has important practical implications for the maintenance of biodiversity but has received few rigorous tests. We tested the hypothesis that maximum taxon richness of macroinvertebrates will occur in communities subject to intermediate levels of disturbance at 54 stream sites that differed in the frequency and intensity of flood-related episodes of bed movement.
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Our results support the intermediate disturbance hypothesis, with both highly mobile and relatively sedentary taxa conforming to the predicted bell-shaped curve. Taxon richness was not related to habitat area (stream width), distance from the headwater, or the diversity of microhabitats (particle size categories) but was significantly and negatively related to the proportion of the substratum made up of small particles. Of all the factors measured, however, bed disturbance was by far the best at accounting for variation in taonomic richness. We also quantified several kinds of potential refugia for invertebrates and found a positive relationship between richness and refugia axis that combines amount of dead space with proportion of large substratum particles. van der Kamp, B. J. 1995. The Spatial Distribution of Armillaria Root Disease in an Uneven-Aged, Spatially Clumped Douglas-Fir Stand. Can. J. For. Res. 25: 1008- 1016.
Abstract: The location, species, and infection status of all tees and stumps in nine 40 by 40 m plots located in a single large Armillaria root disease (caused by Armillaria ostoyae (Romagnesi) Herink) infested area in the Interior Douglas-fir Zone in British Columbia were recorded. The area was logged to a diameter limit in 1963 and then left undisturbed. Spatial analysis using variance over mean ratios of number of trees per grid square for a series of grid sizes showed that stumps were randomly distributed, trees were strongly clumped, and infected trees occurred in small clumps that were themselves randomly distributed. Analysis of intertree distances showed that clumps of infected trees ranged from 1 to 29 trees (average 3.2 trees). Incidence of infection did not decline with distance from old stumps. Infection incidence in spatial domains surrounding each stump ranged from 0 to 100 percent. Nevertheless, variation in incidence among stump domains could not be attributed to variation in inoculum potential at the time of logging. It is concluded that in the experimental area, 30 years after the last major disturbance by partial cutting, Armillaria occurs in small domains, largely on the root systems of trees regenerated since logging. In these circumstances, bridge tree removal spacing, which removes all trees from a band around each infected tree, may isolate most of the viable Armillaria inoculum colonies from the remainder of the stand.
Wilson, J. S. and Oliver, C. D. 2000. Stability and Density Management in Douglas-Fir Plantations. Can. J. For. Res. 30: 910-920.
Abstract: Limited tree size variation in coastal Oregon, Washington, and British Columbia Douglas-fir (Pseudotsuga meniesii (Mirb.) Franco) plantations makes them susceptible to developing high height to diameter ratio (H/D same units) in the dominant trees. The H/D of tree is a relative measure of stability under wind and snow loads. Experimental plot data from three large studies was used to evaluate the impact of initial planting densities and thinning on plantation H/D values. The H/D predictions from the experimental plot data match spacing trial results closely but are substantially different than distance-independent growth model predictions. The results suggest that plantation H/D values can be lowered and stability promoted
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though reduced planting densities or early thinning; however, later thinning may not be effective in promoting stability, since they do not appear to lower H/D values. Higher initial planting densities shorten the time period during which thinning can be expected to effectively lower future H/D values. Time-sensitive thinning requirements in dense plantations make their management inflexible. The flexibility with which a stand can be managed describes the rigidity of intervention requirements and (or) potential range of stand development pathways.
Wright, H. E. 1981. The Role of Fire in Land/Water Interactions. In Proceedings of the Conference Fire Regimes and Ecosystem Properties, U.S. Department of Agriculture Forest Service.
Abstract: Forest fires cause a temporary increase in runoff to streams and lakes, in part because of decreased evapotranspiration, according to studies in Washington (Entiat Fire), Minnesota (Little Sioux Fire), and Ontario (Experimental Lakes Area). Mass transport of nutrients and cations also increases, but no algal blooms were detected. Extent of fires is commonly limted by natural firebreakes provided by lakes and streams. The charcoal and pollen stratigraphy of annually lamited lake sediments provides a record of past fire frequency. Lake-sediment studies also document forest history over thousands of years, showing the shift from fire-adapted forests to fire- resistant forests, or the reverse.
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Supporting Summary Documents
Alexander, R. R. 1987. Ecology, Silviculture, and Management of the Engelmann Spruce - Subalpine Fir Type in the Central and Southern Rocky Mountains. Agriculture Handbook No. 659. Washington, DC: U.S. Department of Agriculture Forest Service.
Abstract: Summarizes and consolidates ecological and silvicultural knowledge of spruce-fir forests. Describes the biological and environmental values, stand regeneration, stand management, and growth and yield.
Bachelet, D. and Neilson, R. P. 2000. Biome Redistribution Under Climate Change. In The Impact of Climate Change on American’s Forests, edited by Joyce, L. A. and Birdsey, R. Fort Collins, CO: U.S. Department of Agriculture Forest Service.
Summary: This chapter addresses the following question: To what geographic extent will potential ecosystem types change or move across the United States, as measured in composition and boundary changes? To do so, the authors used results from three different studies and three different models (DOLY, MAPSS, and BIOME3) at two different spatial resolutions. Results include a discussion of North American, continental U.S., and regional impacts and implications. Results also include a discussion of model limitations, one of which is their ability to accurately predict the impact of disturbance (fire, drought, flooding, hail, hurricanes, and tornadoes).
Bachelet, D., Lenihan, J. M., Daly, C., et al. 2001. MC1: A Dynamic Vegetatioon Model for Estimating the Distribution of Vegetation and Associated Ecosystem Fluxes of Carbon, Nutrients, and Water:Technical Documentation, Version 1.0. PNW-GTR- 508. Portland, OR: U.S. Department of Agriculture Forest Service.
Abstract: Assessments of vegetation response to climate change have generally been made only by equilibrium vegetation models that predict vegetation composition under steady-state conditions. These models do not simulate either ecosystem biogeochemical processes or changes in ecosystem structure that may, in turn, act as feedbacks in determining the dynamics of vegetation change. MC1 is a new dynamic global vegetation model created to assess potential impacts of global climate change on ecosystem structure and function at a wide range of spatial scales from landscape to global. This new tool allows us to incorporate transient dynamics and make real time predications about the patterns of ecological change. MC1 was created by combining physiologically based biogeographic rules defined in the MAPSS model with a modified version of the biogeochemical model, CENTURY. MC1 also includes a fire module, MCFIRE, that mechanistically simulates the occurrence and impacts of fire events.
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Beukema, S. J., Greenough, J. A., Robinson, D. C. E., et al. 1997. An Introduction to the Fire and Fuels Extension to FVS. In Proceedings: Forest Vegetation Simulator Conference. Ogden, UT: U.S. Department of Agriculture Forest Service.
Abstract: The fire Effects Model Extension is a new extension to FVS and PPE that allows users to simulate the effects of fire on a number of indicators, including stand structure and composition, fuel loading, and size and density of snags. In the absence of fire, the model can be used to simulate snag and fuel dynamics resulting from tree growth and mortality and stand management. While the model produces indicators of stand risk t fire (in terms of potential flame length), the model cannot be used to simulate fire spread or the probability of a fire. A brief description of the model is given here, with some sample results showing some of the new indicators at the stand and landscape level.
Campbell, I. C. and Doeg, T. J. 1989. Impact of Timber Harvesting and Production on Streams: A Review. Aust. J. Mar. Freshwater Res. 40: 519-539.
Abstract: Timber harvesting operations have significant effects on both water quantity and water quality. The effects on water quantity have been well documented both in Australia and elsewhere. The effects on water quality are less widely appreciated, and include elevated concentrations of dissolved salts, suspended solids and nutrients, especially during peak flow periods. Several Australian studies have failed to measure peak flow transport of suspended solids, or have measured it inadequately, thus severely underestimating transport.
The major short-term effects of timber harvesting on the aquatic biota result from increased sediment input into streams or increased light through damage to, or removal of, the riparian vegetation. Sediment which settles on, or penetrates into, the stream bed is of more concern than suspended sediment, and can lead to long-term deleterious changes to fish and invertebrate populations. Increased light causes an increase in stream primary production which may increase invertebrate densities, and alter community composition. These biological consequences have not yet been adequately investigated in Australia. Longer-term effects, as yet not investigated in Australia, include changes to stream structure as the re-growth forest has fewer large logs to fall into the stream. These large logs play a major role as habitat and retention structures in streams.
There has been no attempt to evaluate the effects of timber production activities, including pesticide use and fuel reduction burning on the Australian stream biota. Likewise, although buffer zones are widely advocated as a protection measure for streams in Australia, there have been no studies to evaluate their effectiveness.
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Carlson, C. E. 1989. Influence of Habitat Types on Forest Pests of the Northern Rocky Mountains. In Proceedings - Land Classifications Based on Vegetation: Applications for Resource Management. U.S. Department of Agriculture Forest Service.
Abstract: Major pests of Northern Rocky Mountain forests are affected by environmental conditions and vegetation depicted by habitat types (h.t.), but the interactions are weakly understood. Mountain pine beetle activity is limited in high- elevation PICO and ABLA h.t.'s where weather is very cold and moist, but is high in mid-elevation ABLA and PSME types where weather is more moderate. Western spruce budworm is most active on dry, warm PSME and ABGR h.t.'s, and similar to the beetle, is least active in the cold, wet ABLA types. Armillaria spp. occur most frequently in the productive ABGR, THPL, and TSHE h.t.'s but cause most damage in the poorer PSME and ABGR types. Susceptibility (probability of occurrence) and vulnerability (probability of damage) to all three pests seem to depend on relative shade tolerance of the host species. In general, when more than one host species is present, the most shade-tolerant ones, or the indicated climax, will be most susceptible and vulnerable to the pest. But when only one host species is present, and it is seral--such as lodgepole pine on ABLA h.t.s'--it may be extensively exploited by the pest. Multiple-use values are usually enhanced when forest management is structured to favor the seral species.
Childs, T. W. 1968. Elytroderma Diseaseof Ponderosa Pine in the Pacific Northwest. Research Paper PNW-69. Portland, OR: U.S. Department of Agriculture Forest Service.
Abstract: The needle cast of Pinus ponderosa caused by Elytroderma deformans is a native disease that intermittently causes severe local damage. The fungus is perennial within the host, where it spreads vegetatively from one twig or branch to another. Even in its vegetative stage the fungus appears unusually sensitive to climatic stresses.
Foliage on infected twigs dies early in its second year, and the twigs usually die within a few years. Growth rates are reduce in approximated proportion to extent of crown damage. Uncrowded saplings and poles with healthy leaders can recover eventually from fairly severe infection if they are not attacked by other parasites while weakened. In mature stands, crown damage from extensive killing of twigs and branches is permanent, moderately infected trees become and remain more susceptible to root disease and beetle attack, and heavily infected trees are often killed directly by defoliation.
Despite its alarming appearance in outbreak centers, the disease is just another of the many normal hazards to which forests are subject. It does not threaten to exterminate ponderosa pine as a commercial species even on local areas, and usual good management practices should go far towards reducing its future inroads.
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Cochran, P. H. and Dahms, W. G. 1998. Lodgepole Pine Development After Early Spacing in the Blue Mountains of Oregon. PNW-RP-503. Portland, OR: U. S. Department of Agriculture Forest Service.
Abstract: Seedlings were thinned to spacing of 6, 9, 12, 15 and 18 feet and measured periodically. Twenty-seven years after treatment, quadratic mean diameters increased curvilinearly (p <0.05) as spacing increased, but total height did not differ significantly (p<0.05) with spacing. Corresponding basal areas decreased curvilinearly (p<0.05), and cubic volumes decreased linearly (p<0.05) as spacing increased. All periodic annual increments differed with period or age. Periodic annual increments for mean diameter and basal area varied curvilinearly (p<0.05), whereas volume increments varied linearly (p<0.05) with spacing for each period. Height increments were greatest at intermediate spacing during some periods, at wide spacing during other periods, and at the narrowest spacing during one period. Crown widths increased (p<0.05) as spacing widened. Fifty percent crown cover was attained at a stand density index of about 80 for all spacing. Simulation to a breast high age of 100 years indicated that the most merchantable cubic volume was produced at the 6-foot spacing but that the 12-, 15-, and 18-foot spacing produced about the same board-foot volume.
Coulson, R. N. 1979. Population Dynamics of Bark Beetles. Annu. Rev. Entomol. 24: 417- 447.
Abstract: A discussion and presentation of a structure for the population system of bark beetles, focusing on the genus Dendroctonus. Considers the interaction of bark beetles and their hosts at three levels of organizational complexity: the tree, the stand, and the forest. Specific objectives are to (a) define a temporal-spatial structure as the basic population unit of bark beetles; (b) to investigate the operation of the basic population system at the infestation (stand) level of organization; and (c) to investigate the consequences of the operation of the infestation population system at the forest (ecosystem) level of organization.
Covington, W. W. and Moore, M. M. 1994. Southwestern Ponderosa Forest Structure. Journal of Forestry: 39-47.
Abstract: Southwestern ponderosa pine forests are a classic example of how Euro- American populations changed forest conditions. Before settlement, these forests were much more open and parklike. Postsettlement increases in tree density have contributed to changes not only in ecological patterns and processes but also in timber, forage, water, wildlife, and esthetic conditions. This study quantifies some of the associated shifts in ecosystem structure and resource conditions and predicts changes 40 years into the future. The results from this and subsequent studies on other sites should serve as a reference point or baseline for eventual restoration of more nearly natural patterns and processes.
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Cramer, W. and Steffen, W. 1997. Forecast Changes in the Global Environment: What They Mean in Terms of Ecosystem Responses on Different Time-Scales. In Past and Future Rapid Environmental Changes: The Spatial and Evolutionary Responses of Terrestrial Biota. Edited by Huntley, B. and Huntley, B. Berlin: Springer-Verlag.
Summary: The authors briefly discuss the following topics: the nature of anticipated global environmental change, rates and patterns of anticipated climate change, impacts on and feedbacks from land surface processes, short and long term dynamics in current terrestrial land surface models, types of ecosystem responses and ways to simulate them on a global scale, and modelling medium-term dynamics.
Cramer, W., Shugart, H. H., Noble, I. R., et al. 1999. Ecosystem Composition and Structure. In The Terrestrial Biosphere and Global Change: Implications for Natural and Managed Ecosystems, edited by Walker, B. Cambridge: Cambridge University Press.
Abstract: The structure of terrestrial ecosystems influences their responsiveness to most drivers of global change: for example, growth responses to enhanced CO2 are less at higher levels of organization and over longer periods of observation.
The future structure and composition of terrestrial ecosystems will be affected by reponses at the patch, landscape and global scales. Direct extrapolation from the patch to the globe is unlikely to yield realistic projections of ecosystem change; landscape-scale processes must be taken into account.
A general finding from patch model studies is that many forests appear to be sensitive to global change on the time scale of centuries. On shorter time scales, e.g. for the next few decades, many forests will show little response due to the lag effects in demographic processes. However, in systems where intense disturbances are more common, or become more common under global change, there will be opportunities for mortality and replacement of existing trees, and changes in forest structure and composition may be more rapid.
The interaction of global change and landscape phenomena can greatly modify both the magnitude and rate of change in community composition and structure. The importance of self-organization in landscape dynamics implies that change will not be incremental and smooth, but instead, punctuated and lumpy.
Migration plays a critical role in the process of ecosystem adaptation to climate change; human modification of landscapes affects the possible velocity of migration. Migration rates through the markedly non-random landscapes created by human activities are usually slower than those based on predictions derived from theoretical studies based on randomly fragmented landscapes. Many species may face a 'double bind' in which they need to migrate in response to climate change, but have few places to go and too much hostile territory to cross.
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Assessments of the response of the terrestrial biosphere to global change are moving from an equilibrium towards a dynamic representation, triggered by the recognition that two major problems exist in the equilibrium assessments: By definition, equilibrium models simulate no transient changes in vegetation. Therefore, these simulations may at best be used to indicate the direction of possible change but not the time it might take to reach the new conditions.
Evidence from the past show that biomes are unlikely to be displaced as homogenous entities. Rather, differences in species’ fundamental ecological niches, and their widely varying abilities to migrate, will result in quite different assemblages over a long period of time.
Dahl, D. W., Pyne, S., Anderson, E. V., et al. 1981. Fire and Public Policy. In Proceedings of the Conference Fire Regimes and Ecosystem Properties. Washington D. C.: U.S. Department of Agriculture Forest Service.
Abstract: The fire management policy of the USDA Forest Service was revised in 1978 to permit cost-effective fire suppression tactics to be employed. Further, fire management activities are directed to meet land management objectives. This paper examines some of the factors involved with changing fire management policy. Emphasis is on the influence of the Industrial Revolution, European culture, 1910 fires, mores of early foresters in America, scientific technology, philosophy, and the post-1910 period including the influence of the Civilian Conservation Corps. Public policy is presented as a dynamic political manifestation of interactions of these factors.
Dale, V. H., Joyce, L. A. and McNulty, S. 2000. The Interplay Between Climate Change, Forests, and Disturbances. The Science of the Total Environment 262: 201-204.
Abstract: Climate change affects forests both directly and indirectly through disturbances. Disturbances are a natural and integral part of forest ecosystems, and climate change can alter these natural interactions. When disturbances exceed their natural range of variation, the change in forest structure and function may be extreme. E ach disturbance affects forests differently. Some disturbances have tight interactions with the species and forest communities which can be disrupted by climate change. Impacts of disturbances and thus of climate change are seen over a broad spectrum of spatial and temporal scales. Future observations, research, and tool development are needed to further understand the interactions between climate change and forest disturbances.
Ehlert, H. and Mader, S. 2000. Review of the Scientific Foundations of the Forests and Fish Plan. Bellevue, WA: CH2M Hill.
Summary: This review identifies the scientific foundations for the recommendations contained in the Forests and Fish Report and assesses the effectiveness of the recommendations in meeting the goals set forth by the Washington Forest Practices
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Board. The document contains background information on the Forest and Fish Report and its legal and scientific context. It also contains "functional discussions" in seven issue areas: (1) Large Woody Debris; (2) Heat Energy; (3) Coarse Sediment; (4) Fine Sediment; (5) Hydrology; (6) Pesticides; and (7) Litterfall.
Everett, R. L. and Baumgartner, D. M. 1997. Disturbance Management and Resource Product Availability. In Proceedings Forest Products for Sustainable Forestry, IUFRO. Pullman, WA: Washington State University.
Abstract: Disturbance is an integral part of ecosystem process; its conservation is of equal importance as the conservation of species or habitats, and it provides an ecological approach to resource product availability. Disturbance management is a technique that can be used to maintain ecosystem integrity and associated sustainable levels of commodity extraction on public lands. Public expectations for resource conditions and resource extraction need to be grounded in the reality of required disturbance regimes to maintain ecosystem integrity. The mosaic of post-disturbance vegetation patches contributing to biodiversity also represents a portfolio of economic opportunities. Management for disturbances and resulting patch dynamics across large landscapes in "whole-unit management" is suggested as a flexible institutional approach to resource management that incorporates planned and unplanned disturbances into long-term management goals for ecosystem integrity and resource extraction.
Everett, R. L., Lehmkuhl, J. F., Jensen, M. E., et al. 1995. Application of the Eastside Forest Ecosystem Health Assessment to Ecosystem Management. In Proceedings, Forest Health and Fire Danger in Inland Western Forests September 8-9, 1994, Spokane, WA. Washington, DC: American Forests.
Summary: A short overview of the Eastside Forest Ecosystem Health Assessment and its efforts to construct an ecosystem management framework for six river basins in eastern Oregon and Washington. The overview includes a discussion of the project's conceptual framework, a description of the assessment findings and how they should be applied, and three recommendations for Eastside land managers.
Everett, R., Schellhaas, D., Spurbeck, D., et al. 1997. Structure of Northern Spotted Owl Nest Stands and Their Historical Conditions on the Eastern Slope of the Pacific Northwest Cascades, USA. Forest Ecology and Management 94: 1-14.
Abstract: The northern spotted owl (Strix occidentalis caurina ) uses a wide array of nesting habitat throughout its current range and successfully reproduces in a variety of stand types on the eastern slope of the Pacific Northwest Cascades. The species has the ability to utilize dynamic forest stands that continue to undergo significant changes in tree density, proportion of tree size classes, and tree species composition. Current stand structure and composition reflect the results of timber harvest, reduced fire effects and ongoing successional and stand development processes. In nest stands, multi-layered canopy was more strongly expressed in numbers of both small
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(<13 cm DBH) and large (>14 cm DBH) trees than in unoccupied stands of the same type within the owl neighborhoods. Tree density and the proportion of shade-tolerant tree species have increased significantly in spotted owl nest sites in both dry and wet forests since Eurosettlement. Barring disturbance, further increases in the dominance of shade-tolerant species should occur over time with continual change in nest stand structure and composition. The development of dense forest stands and "old-forest structural attributes" as a result of reduced fire effects could be potential mitigating factors to the loss of old-forest habitat from harvest and should be considered in determining the available owl habitat in the eastern Cascades. However, old-forest structural attributes in dense, overstocked stands are at high fire hazard and should be viewed as transitional until old-forest habitat with improved sustainability becomes available.
Franklin, J. F. and Blinn, T. 1988. Natural Vegetation of Oregon and Washington: Commentary and Bibliographic Supplement. Corvallis, OR: Oregon State University Press for the U.S. Department of Agriculture Forest Service.
Summary: A supplemental bibliography to the 1973 Pacific Northwest vegetation classification “Natural Vegetation of Oregon and Washington.” Contains over 500 publications considered by the authors to be relevant to the areas of: plant community analysis and classification, disturbance ecology, and ecosystem processes.
Franklin, J. F., Shugart, H. H. and Harmon, M. E. 1987. Tree Death as an Ecological Process. BioScience 37(8): 550-556.
Abstract: An overview of tree death as a rich ecological process. Included are the causes of tree death, its consequences, its variability, and the importance of species’ natural histories. The authors also use tree death to illustrate some general aspects of ecological processes.
Gresswell, R. E. 1998. Fire and Aquatic Ecosystems in Forested Biomes of North America. American Fisheries Society 128: 193-221.
Abstract: Synthesis of the literature suggests that physical, chemical, and biological elements of a watershed interact with long-term climate to influence fire regime, and that these factors, in concordance with the postfire vegetation mosaic, combine with local-scale weather to govern the trajectory and magnitude of change following a fire event. Perturbation associated with hydrological processes is probably the primary factor influencing postfire persistence of fishes, benthic macroinvertebrates, and diatoms in fluvial systems. It is apparent that salmonids have evolved strategies to survive perturbations occurring at the frequency of wildland fires (1 - 100 years), but local populations of a species may be more ephemeral. Habitat alteration probably has the greatest impact on individual organisms and local populations that are the least mobile, and reinvasion will be most rapid by aquatic organisms with high mobility. It is becoming increasingly apparent that during the past century fire suppression has altered fire regimes in some vegetation types, and consequently, the
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probability of large stand-replacing fires has increased in those areas. Current evidence suggests, however, that even in the case of extensive high-severity fires, local extirpation of fishes is patchy, and recolonization is rapid. Lasting detrimental effects on fish populations have been limited to areas where native populations have declined and become increasingly isolated because of anthropogenic activities. A strategy of protecting robust aquatic communities and restoring aquatic habitat structure and life history complexity in degraded areas may be the most effective means for insuring the persistence of native biota where the probability of large-scale fires has increased.
Haack, R. A. and Byler, J. W. 1993. Insects and Pathogens: Regulators of Forest Ecosystems. Journal of Forestry: 32-37.
Summary: An article that describes how insects and pathogens can be considered beneficial from an ecosystem perspective. Focusing on “forest health” – or the ability of a forest to recover from natural or human-cause stressors – the authors discuss how insects and pathogens affect forest succession, carbon and nutrient cycling, food sources, the creation of wildlife habitat, and pollination.
Hadfield, J. S., Goheen, D. J., Filip, G. M., et al. 1986. Root Diseases in Oregon and Washington Conifers. Portland, OR: U.S. Department of Agriculture Forest Service.
Abstract: Root diseases are responsible for large losses of timber in Pacific Northwest forests. All conifer species and all forested areas suffer damages from root diseases. This booklet has been prepared for foresters and others concerned with controlling conifer root diseases in Oregon and Washington forests. It describes how to recognize the most important root diseases, how they spread and damage host trees, and how to reduce losses. Resource productivity of infested sites can be significantly expanded by controlling root diseases.
The information presented has been compiled from many sources and represents more than 75 years of research and observations by forest pathologists in the Pacific Northwest.
Hagle, S. K., McDonald, G. I., Norby, E. A. 1989. White Pine Blister Rust in Northern Idaho and Western Montana: Alternatives for Integrated Management. GTR-INT- 261. Ogden, UT: U.S. Department of Agriculture Forest Service.
Abstract: This report comprises a handbook for managing western white pine in northern Idaho and western Montana, under the threat of white pine blister rust. Various sections cover the history of the disease and efforts to combat it, the ecology of the white pine and Ribes, alternate host of the rust, and techniques for evaluating the rust hazard and attenuating it. The authors advocate an integrated control strategy based on local stand conditions. Options include planning resistant strains of pine, excising cankers, and chemical, mechanical, and silvicultural control of Ribes.
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Hawksworth, F. G. 1977. The 6-Class Dwarf Mistletoe Rating System. General Technical Report RM-48. Fort Collins, CO: U.S. Department of Agriculture Forest Service.
Abstract: Several rating systems have been proposed to describe the intensity of dwarf mistletoe infection in individual trees or stands, but the 6-class dwarf mistletoe rating (DMR) system, described in 1956, has been most widely adopted. This system is being used for several dwarf mistletoe host/parasite combinations in western North America. Uses and limitations of the 6-class system are discussed, and several applications of the system are cited.
Hopkins, J. C. and Callan, B. 1991. Atropellis Canker. Forest Pest Leaflet 29-6/25. Victoria, British Columbia: Forestry Canada.
Abstract: Atropellis piniphila (Weir) Lohman and Cash is a fungus that causes perennial stem and branch cankers of lodgepole pine (Pinus contorta Dougl.). In locations where this disease is prevalent, most or all host trees may become infected and multiple stem and branch infections are common. The disease reduces the value of trees for lumber, or pulp and many countries prohibit its importation in lumber.
This leaflet describes A. piniphila, one of four North American species of the genus which cause disease in pines. The information provided is probably also applicable to A. pinicola Zeller and Goodding. Atropellis pinicola, which attacks western white pine (P. monticola Dougl.) and, occassionally, lodgepole pine, is the only other species of Atropellis found in B. C.
Johnson, D. W. and Hawksworth, F. G. 1985. Dwarf Mistletoes: Candidates for Control through Cultural Management. In Insect and Disease Conditions in the United States 1979-1983: What Else is Growing in Our Forests? (WO-GTR-46). Washington, D. C.: U.S. Department of Agriculture Forest Service.
Summary: The dwarf mistletoes are one of the most widespread and damaging groups of forest diseases in North America. This overview generally describes their evolution, how they have affected timber and recreational forest resources throughout the United States, and how they can be prevented or suppressed in the future.
Johnson, D. W. 1986. Comandra Blister Rust. Forest Insect & Disease Leaflet 62. Washington D.C.: U.S. Department of Agriculture Forest Service.
Summary: An overview of Comandra Blister Rust, a disease of hard pines that is caused by a fungus growing in the inner bark. Includes a discussion of the following elements: range and hosts, life cycle and spread, damage, symptoms, factors affecting outbreaks, control recommendations, and a description of the future of rust control.
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Kipfmueller, K. F. and Swetnam, T. W. 2001. Using Dendrochronology to Reconstruct the History of Forest and Woodland Ecosystems. In The Historical Ecology Handbook: A Restorationist`s Guide to Reference Ecosystems. Washington: Island Press.
Abstract: In this chapter we review the guiding principles of dendrochronology as they relate to reconstruction of the ecological history of forests and woodlands. We also discuss some basic techniques and practices used to cross-date and ensure accurate dating of tree rings. Unsing"classic" and recent examples, we focus on the use of dendrochronology to understand the mechanisms of ecological change and variability across time and space, and on applications toward the restoration of ecosystems. Finally, we discuss some important limitations of dendrochronology as a tool for historical ecology.
Kovalchik, B. L 2001. The Classification of Aquatic, Riparian and Wetland Sites on the National Forests of Eastern Washington:(Part 1: The Series). Paper presented at ERSAG Forest Dynamics Workshop, February, Spokane, WA.
Abstract: The intent of this presentation is not to lay blame for the trend to oversimplify riparian zones--but to explain how a aquatic/riparian/wetland classification may -- through a hierarchical, geomorphic view of riparian and wetland zones -- help managers:
• better understand functions and processes in these zones Formatted: Indent: Left: 0.75", Bulleted + Level: 1 + Aligned at: 0.5" + Tab after: 0.75" + Indent at: 0.75", Tab stops: Not at 0.75" • make reasonable estimates of the status and potential of these zones Formatted: Indent: Left: 0.75", Bulleted + Level: 1 + Aligned at: 0.5" + Tab after: 0.75" • help prescribe proper management direction for riparian and wetland zones + Indent at: 0.75", Tab stops: Not at 0.75" Formatted: Indent: Left: 0.75", Bulleted + Level: 1 + Aligned at: 0.5" + Tab after: 0.75" • help with salmon recovery efforts by providing site-based stratification of + Indent at: 0.75", Tab stops: Not at 0.75" landscapes and data for evaluating desired future conditions (targets). Formatted: Indent: Left: 0.75", Bulleted + Level: 1 + Aligned at: 0.5" + Tab after: 0.75" Kulman, H. M. 1971. Effects of Insect Defoliation on Growth and Mortality of Trees. + Indent at: 0.75", Tab stops: Not at 0.75" Annual Review of Entomology 16: 289-324.
Summary: A review of quantitative studies of tree mortality and increment reduction related to measured amounts of insect and artificial defoliation in which the foliage is removed at the time of treatment. Included are discussions of artificial defoliation as well as defoliation by a range of pests: sawfly, Jack Pine budworm, spruce budworm, lodgepole needle miner, dendrolimus species, miscellaneous lepidoptera, gypsy moth, forest tent caterpillar.
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Landres, P. B., Morgan, P. and Swanson, F. J. 1999. Overview of the Use of Natural Variability Concepts in Managing Ecological Systems. Ecological Applications 9(4): 1179-1188.
Abstract: Natural resource managers have used natural variability concepts since the early 1960s and are increasingly relying on these concepts to maintain biological diversity, to restore ecosystems that have been severely altered, and as benchmarks for assessing anthropogenic change. Management use of natural variability relies on two concepts; that past conditions and processes provide context and guidance for managing ecological systems today, and that disturbance-driven spatial and temporal variability is a vital attribute of nearly all ecological systems. We review the use of these concepts for managing ecological systems and landscapes.
We conclude that natural variability concepts provide a framework for improved understanding of ecological systems and the changes occurring in these systems, as well as for evaluating the consequences of proposed management actions. Understanding the history of ecological systems (their past composition and structure, their spatial and temporal variability, and the principal processes that influenced them) helps managers set goals that are more likely to maintain and protect ecological systems and meet the social values desired for an area. Until we significantly improve our understanding of ecological systems, this knowledge of past ecosystem functioning is also one of the best means for predicting impacts to ecological systems today.
These concepts can also be misused. No a priori time period or spatial extent should be used in defining natural variability. Specific goals, site-specific field data, inferences derived from data collected elsewhere, simulation models, and explicitly stated value judgment all must drive selection of the relevant time period and spatial extent used in defining natural variability. Natural variability concepts offer an opportunity and a challenge for ecologists to provide relevant information and to collaborate with managers to improve the management of ecological systems.
Lindenmayer, D. B. 1995. Forest Disturbance, Forest Wildlife Conservation and the Conservative Basis for Forest Management in the Mountain Ash Forests of Victoria - Comment. Forest Ecology and Management 74: 223-231.
Abstract: A recent interview by Attiwill outlined a range of aspects of disturbance regimes in forests and attempted to demonstrate their value in developing a basis for the "conservative management" of wood production areas. One of the key themes in these papers-that natural disturbance regimes should be a model for forest management, is a good one. However, there are major difficulties in determining the intensity, frequency and extent of timber harvesting operations that mimic "natural disturbance regimes" and, in turn, form the basis of "conservative management" strategies which account for the full spectrum of forest values. This paper highlights a few of the many key considerations for truly integrated multiple-use forest management that were overlooked by Attiwill and which are an essential component
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of ecologically sustainable forest management. These relate to aspects of the conservation of forest wildlife that are sensitive to forest disturbances resulting from timber harvesting operations. Many of the examples of the response of wildlife to forest disturbance outline by Attiwill are from the mountain ash (Eucalyptus regnans) forests of Victoria, south-eastern Australia. Unlike the impression given by Attiwill, the results of the array of detailed long-term studies on forest fauna in mountain ash forests that have been completed to date clearly indicate that balancing the multiple values of mountain ash forests will be a complex task requiring major modifications to present multiple forest-use management strategies. This is because of the potential for current forestry activities to both: (1) produce long-term modifications to key components of vegetation structure and thus habitat suitability for fauna (e.g. old growth elements such as trees with hollows) and (2) fragment remaining patches of suitable habitat and create sub-divided populations that may not be viable in the long- term. Moreover, because a given species has survived disturbance regimes in the past, it is premature to suggest that it will persist in the future when new and recent forms of forest perturbation such as clearfelling are intensively and extensively applied throughout large areas of the forest landscape. In mountain ash forests, a conservative basis for forest management will require much more than the creation of a series of ages of regrowth forest as implied by Attiwill, but also the establishment of more and larger areas of old growth forest and/or modifications of clearfelling regimes to better allow for the development of suitable habitat for wildlife that are sensitive to the impact of timber harvesting, such as the endangered arboreal marsupial Leadbeater's possum (Gymnobelideus leadbeateri). Until management strategies that are more sympathetic to wildlife conservation are embraced, there remains a high probability that Leadbeater's possum, and other species with similar habitat requirements, could be eliminated from some wood production areas, implying that current forestry practices are not ecologically sustainable in the long- term.
MacDonald, L. H. and Smart, A. 1993. Beyond the Guidelines: Practical Lessons for Monitoring. Environmental Monitoring and Assessment 26: 203-218.
Abstract: A series of workshops have provided extensive feedback on a recently published manual, Monitoring Guidelines to Evaluate Effects of Forestry Activities on Streams in the Pacific Northwest and Alaska (Guidelines) (MacDonald et al, 1991). These workshops and other discussions have led to the identification of fourteen additional lessons for monitoring. These lessons are concepts which either were not incorporated into the Guidelines, were not sufficiently emphasized, or which are needed to put the Guidelines in context. The topics include: monitoring as a continuum; defining objective and hypotheses; peer review; uncertainly and risk; upslope vs. instream monitoring; photo-sequences; scale considerations; data storage, data interpretation, and data base management; activities monitoring; and personal commitment as a critical component in monitoring projects. Many of these lessons might appear self-evident, but our experience indicate that they are often ignored. Like the Guidelines, these lesson are widely applicable and should be explicitly recognized when formulating and conducting monitoring projects.
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Malcolm, J. R., Markham, A., Neilson, R. P. 2001. Can Species Keep Up with Climate Change? Conservation Biology in Practice 2(2): 24-25.
Abstract: Although species have inherent abilities to respond to climatic shifts, the speed at which they can respond is limited. If climatic conditions shift quickly enough, slower moving species may be left behind - especially if human activities have destroyed and fragmented existing habitat.
Instead of attempting to predict how fast species and biomes might be able to move, we analyzed how fast they might be required to move to kepp up with projected warming. We used global climate and vegetation models to address three key questions: (1) How do possible future migration rates compare with past rates? (2) Are migration rates uniform across the planet? (3) How will human behavior influence these future rates?
Maruoka, K. R. and Agee, J. K. 1994. Fire Histories: Overview of Methods and Applications. Technical Notes from the Blue Mountains Natural Resources Institute Tech Memo #2: 1-7.
Abstract: The two main approaches to developing a fire history are through analysis of point frequencies and area frequencies. Point frequencies assess fire occurrence at one location while are frequencies assess fire occurrence at the scale of the landscape. Although both yield a "fire frequency," the frequencies represent different types of information because of this difference in scale. Selecting the appropriate method depends primarily on the vegetation types and physical features of the study area, as well as the type of fire evidence present.
Meehan, W. R. 1996. Influence of Riparian Canopy on Macroinvertebrate Composition and Food Habits of Juvenile Salmonids in Several Oregon Streams. PNW-RP-496. Portland, OR: U.S. Department of Agriculture Forest Service.
Abstract: The community composition of macroinvertebrates and the feeding habits of juvenile salmonids were studies in eight Oregon streams. Benthic, drift, sticky trap, and water trap samples were taken over a 3-year period, along with stomach samples of the fish. Samples were taken in stream reaches with and without riparian canopy.
Both main effects--fish diet versus macroinvertebrate composition in the environment, and canopied versus noncanopied stream condition--were highly significant, but probably not practical importance in terms of the amount of preferred food available to the fish.
In all aquatic sample types, inclding fish stomaches, Diptera and Ephemerooptera were in predominant invertebrates collected. In sticky trap and water trap samples, Diptera and Collembola were the predominant orders, relecting the input of terrestrial invertebrates.
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Moore, M. M., Covington, W. W. and Fule, P. Z. 1999. Reference Conditions and Ecological Restoration: A Southwestern Ponderosa Pine Perspective. Ecological Applications 9(4): 1266-1277.
Abstract: Ecological restoration is the process of reestablishing the structure and function of native ecosystems and developing mutually beneficial human-wildland interactions that are compatible with the evolutionary history of those systems. Restoration is based on an ecosystem's reference conditons (or natural range of variability); the difference between reference conditions and contemporary conditions is used to assess the need for restorative treatments and to evaluate their success. Since ecosystems are highly complex and dynamic, it is not possible to describe comprehensively all possible attributes of reference conditions. Instead, ecosystem characteristics with essential roles in the evolutionary environment are chosen for detailed study. Key characteristics of structure, function, and disturbance - especially fire regimes in ponderosa pine ecosystems - are quantified as far as possible through dendroecological and paleoecological studies, historical evidence, and comparison to undisrupted sites. Ecological restoration treatments are designed to reverse recent, human-caused ecological degradation. Testing of restoration treatments at four sites in northern Arizona, USA, has shown promise, but the diverse context of management goals and constraints for Southwestern forest ecosystems means that appropriate applications of restoration techniques will probably differ in various settings.
Neilson, R. P. and Marks, D. 1994. A Global Perspective of Regional Vegetation and Hydrologic Sensitivities from Climatic Change. Journal of Vegetation Science 5: 715-730.
Abstract: A biogeographic model, MAPSS (Mapped Atmosphere-Plant-Soil System), predicts changes in vegetation leaf area index (LAI), site water balance and runoff, as well as changes in biome boundaries. Potential scenarios of global and regional equilibrium changes in LAI and terrestrial water balance under 2 x CO2 climate from five different general circulation models (GCMs) are presented. Regional patterns of vegetation change and annual runoff are surprisingly consistent among the five GCM scenarios, given the general lack of consistency in predicted changes in regional precipitation patterns. Two factors contribute to the consistency among the GCMs of the regional ecological impacts of climatic change: (1) regional, temperature-induced increases in potential evapo-transpiration (PET) tend to more than offset regional increases in precipitation: and (2) the interplay between the general circulation and the continental margins and mountain ranges produces a fairly stable pattern of regionally specific sensitivity to climatic change. Two areas exhibiting among the greatest sensitivity to drought-induced forest decline are eastern North America and eastern Europe to western Russia. Regional runoff patterns exhibit much greater spatial variation in the sign of the response than do the LAI changes, even thought they are deterministically linked in the model. Uncertainties with respect to PET or vegetation water use efficiency calculations can alter the simulated sign of regional responses, but the relative responses of adjacent regions
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appear to be largely a function of the background climate, rather than the vagaries of the GCMs, and are intrinsic to the landscape. Thus, spatial uncertainty maps can be drawn even under the current generation of GCMs.
Ohlson, P., Leuschen, T., Everett, R., et al. 1998. Fire Hazard of Spotted Owl Neighborhoods on the East Slope of the Washington Cascades. Paper presented at the Fire Effects on Rare and Endangered Species and Habitats Conference, March 29 – April 1, Okanogan, WA.
Abstract: Forest stand types and their configuration within northern spotted owl (Strix occidentalis caurina) neighborhoods indicate the potential for destructive crown-replacement fires on the eastern slope of the Cascade Range in Washington. Large contiguous blocks of dense, multi-layered forest provide suitable owl habitat but also increase the likelihood of large-scale conflagrations should ignition occur. Following the settlement era of the late 1800's fire suppression efforts altered fire regimes and fire-intolerant understory tree species and coarse wood debris increased beyond levels consistent with the former fire regime. Information about fuel conditions, moisture regimes, landscape topography and frequency of lightning for any given area can provide insights into potential fire hazard. Cluster and discriminant analysis separated 34 spotted owl neighborhoods into 6 distinct crown fire severity groups using fire-free interval (potential ignitions), area of high crown fire potential (hazard), and predicted rate of fire spread. Most fire-free intervals range from 6 to 25 years, but 2 neighborhoods in the pacific silver fir and western hemlock series had intervals near 400 years. Areas of high crown fire potential were calculated to be over 70 percent in some neighborhoods, and fires were estimated to consume up to 13.3 percent of a 1200 acre neighborhood within a 24 hour period. We suggest that forest management concerned with the protection of spotted owls and their habitat should recognize the risk of large-scale fire across the landscape and identify those areas and conditions were fuel treatment can reduce that risk while maintaining viable owl populations.
Parsons, D. J. 1981. The Role of Fire Management in Maintaining Natural Ecosystems. In Proceedings of the Conference Fire Regimes and Ecosystem Properties. Washington, D.C.: U.S. Department of Agriculture Forest Service.
Abstract: Fire, both naturally ignited and man caused, has long played a role in the evolution of many of the world's natural ecosystems. During the past century, fire has often come to be regarded as a destructive force, leading to efforts to eliminate it as an important ecological factor. Yet, if naturally functioning ecosystems are to be maintained, fire must be allowed to play its primeval role. A growing understanding of this necessity in recent years has led to the implementation of integrated fire management programs in many areas. These programs may utilize both lightning- ignited and/or intentionally set or prescribed fires to achieve carefully predetermined resource management objectives. This paper discusses the current status of fire management as well as the background information needed to formulate and implement an integrated fire management program.
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Pickett, S. T. A., Kolasa, J., Armesto, J. J., et al. 1989. The Ecological Concept of Disturbance and Its Expression at Various Hierarchical Levels. Oikos 54: 129-136.
Abstract: Current definitions of disturbance are intuitive, narrow, and only implicitly based on system structure. This is because the concepts are based on experience at particular levels of organization or on systems whose structure is well know. The definitions are thus inadequate for the development of a general theory of ecological disturbance. A universally applicable definition would 1) identify the object disturbed; 2) distinguish between change in the object that is disturbance versus change that is not; and 3) distinguish between direct and indirect consequences of disturbance. Any persistent ecological object will have a minimal structure, or system of lower level entities that permit its persistence. Disturbance is a change in the minimal structure of an object caused by a factor external to the level of interest. Using these definitions, disturbance can be unequivocally identified and associated with various specific ecological levels of organization. Because of the dependence of the concept of disturbance on recognizing the minimal structure of ecological systems, application of the concept will advance as refined models of the hierarchical structure of ecological systems are elaborated.
Pitelka, L. F. 1997. Plant Migration and Climate Change. American Scientist 85: 464-473.
Summary: This summary document discusses interdisciplinary research activities related to plant migration. The discussion focuses on rates of migration, invasion of native pland communities by exotic species, natural and human-assisted dispersion mechanisms and disturbances, landscape patterning, regional problems, and global consequences. Computer models are proposed as a means of understanding the complex interactions of biological, climatic, and geographical components.
Pleus, A. E. 1999. Timber Fish & Wildlife Monitoring Program Method Manual for Wadable Stream Discharge Measurement. TFW-AM9-99-009, DNR 111. Olympia, WA: Washington Department of Natural Resources.
Abstract: The TFW Monitoring Program method manual for the Wadable Stream Discharge Measurement (WSDM) method provides a standard method for the assessment and monitoring of stream discharge on wadable streams. The TFW method follows the USGS protocols (Rantz and others, 1982) with minor modifications for smaller stream systems. Discharge measurements are required for the TFW Habitat Unit and Large Woody Debris Surveys and when conducting portions of the Spawning Habitat Availability and Stream Temperature Surveys.
This introduction section describes the purpose of the WSDM method and describes the cooperator services provided by the TFW Monitoring Pro . Following the introduction, sections are presented in order of survey application including; pre-survey preparation, methods, post-survey documentation, data management, and references. An appendix is also provided that includes: copy masters of field forms; examples of completed field forms; a standard field and
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vehicle gear checklist, and USGS procedures for float and volumetric discharge measurements.
Pleus, A. E. and Schuett-Hames, D. 1998a. Timber Fish & Wildlife Monitoring Program Method Manual for Stream Segment Identification. TFW-AM9-98-001, DNR 103. Olympia, WA: Washington Department of Natural Resources.
Abstract: This manual provides a standard method for systematically identifying stream segments on the basis on channel morphology and floodplain characteristics. These segments are used as the basic framework for designing monitoring study plans and conducting monitoring surveys for the TFW Monitoring Program, Watershed Analysis, and the Salmon and Steelhead Habitat Inventory and Assessment (SSHIAP) process. The primary stream segment characteristics are: 1) stream order/relative basin drainage area; 2) channel gradient; and 3) channel confinement. The manual provides basic segmenting techniques with clear, step-by-step explanations and examples that illustrate the application of the methods in various stream situations. It is divided into office methods, field verification, post-field documentation, and data management sections. A sub-segmenting process has been included to provide flexibility to address the specific needs of individual studies and as a linkage to other stream classification systems. An extensive appendix section includes a materials and equipment source list, copy masters of documentation forms and worksheets, examples of completed forms and worksheets, a glossary, a data report example, and segmenting task checklist.
_____. 1998b. Timber Fish & Wildlife Monitoring Program Method Manual for the Reference Point Survey. TFW-AM9-98-002, DNR 104. Olympia, WA: Washington Department of Natural Resouces.
Abstract: This manual provides a standard method for establishing stable reference point sites for monitoring stream segments over time. Referenced points are established at regular intervals along a previously defined stream segment and monumented to be easily relocated. Stream parameters collected during this survey include: 1) segment length; 2) bankfull width; 3) bankfull depth; 4) canopy closure; and 5) optional reference photographs. The manual is divided into pre-survey preparation, field methods, post-field documentation, and data management sections. An extensive appendix section includes a survey task checklist copy master, a materials and equipment source list, field form copy masters, examples of completed field forms, a data report example, and a glossary of terms.
Pleus, A. E., Schuett-Hames, D., Bullchild, L. 1999. Timber Fish & Wildlife Monitoring Program Method Manual for the Habitat Unit Survey. TFW-AM9-99-003. Olympia, WA: Washington Department of Natural Resources.
Abstract: The TFW Monitoring Program method manual for the Habitat Unit Survey provides a standard method for assessing and monitoring the quantity and quality of habitat in wadable streams. The core Habitat Unit Survey collects
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information on the frequency and distribution of riffle and pool habitat units. Quantitative criteria are used to distinguish and identify habitat units to ensure consistency between observers. The unit's channel location is identified as either primary, secondary, side or tributary channel. Wetland, sub-surface flow, and obscured unit types are also used to characterize portions of the stream that are either flowing through wetland systems, have gone sub-surface, or cannot be identified because visibility is obscured. Additional information is collected on the maximum and outlet depths of pools, and on features associated with pool formation. Guidance is provided for optional collection of sub-unit habitat types. The TFW Monitoring Program database accepts data collected using the Habitat Unit Survey method, performs standard calculations, and generates data summary reports of habitat unit data at 100 meter and stream segment scales.
The remainder of the introduction section describes the purpose of the Habitat Unit Survey, reviews scientific background information, and describes the cooperator services provided by the TFW Monitoring Program. Following the introduction, sections are presented in order of survey application including: study design, pre- survey preparation, methods, post-survey documentation, data management, and references. An extensive appendix is also provided that includes: copy masters of field forms; examples of completed field forms; a field code sheet; a standard field and vehicle gear checklist; data management examples.
Quigley, T. M. n.d. Research Plan for Evaluating Silvicultural Treatments in Fire-Created, Overstocked, Small-Diameter Forest Stands. Unpublished manuscript, U.S. Department of Agriculture Forest Service, Portland, OR.
Abstract: Managing densely stocked stands of small-diameter trees (CROP stands) is a complex challenge. Collaboration f land managers and researches is essential to increasing the knowledge of how management activities can be sued to enhance forest health and ecosystem integrity as well as meet diverse societal needs. In 1996, recognizing and opportunity for stimulating local rural economies while addressing forest health issues, the U.S. Congress (House Report 104-625) provided National Forest Systems with funding and legislative language for "implementation and evaluation of controlled silvicultural treatment in designated fire-generated, overstocked, small-diameter, stagnated forest 'CROP' stands or other stands designated by the Secretary and having 'CRPO' characteristics on the Colville National Forest." Forest Service Research was asked to provide research support for adaptive management activities within these stands. This research plan is a specific product referred to in and mandated by the appropriations bill.
Within this plan we have documented the questions we believe should be addressed within the framework of adaptively management CROP stands and landscapes and providing links between the two scales. Current and future work will be undertaken in the context of priority issues rather than specific research studies, with the primary goal being to provide timely information and technology that assists land managers in managing landscapes to ensure ecological integrity and societal benefits. Throughout
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the plan we have taken an interdisciplinary approach to describing the broad issues and specific researchable questions.
Additionally, we outline the work currently being implemented toward answering some of these questions. Many of the questions we identified cannot be answered by current research, which is focused at the stand level because of the request to begin implementing research within FY97 and because of the necessity for using a site for which NEPA documents exist. That site is the Fritz Demonstration Project where researches will study effects of a variety of harvesting systems on stand conditions such as fuel levels, soil conditions, residual and projected future tree conditions insect and disease risks, and economics. Future work will capitalize on information generated from the Fritz Demonstration Project and begin to address landscape-level and linkage questions along with additional stand-level questions. Additional work initiated in FY97 are two efforts to look at the context of managing CROP stands. One addresses the ecological patterns and relations with a historical perspective and the other looks at the societal desires and needs with a plan to incorporate those findings into the planning for future work.
The development of this plan and the current years research work has already provided an opportunity to bring together the talents and strengths of the management and research branches of the U.S. Forest Service, and that working relationship is another benefit of the adaptive management approach outlined in the document.
Robison, E. G., Mills, K. A., Paul, J., et al. 1999. Oregon Department of Forestry Storm Impacts and Landslides of 1996: Final Report. Forest Practices Technical Report Number 4. Salem, OR: Oregon Department of Forestry, Forest Practices Monitoring Program.
Summary: During the months of February and November 1996, two very large storms affected most of Western Oregon and parts of Northeast Oregon. Both resulted in large numbers of landslides, debris torrents, and altered stream channels. With oversight from a team of experts in the landslide and natural resources fields, the Oregon Department of Forestry implemented a 3-year monitoring project to evaluate the effect of these storms. Ground surveying, aerial photos, and digital elevation models were all used to identify and analyze landslide areas. The study reports several findings relating landslide occurrence and magnitude to forest stand age and management (e.g., timber harvesting, presence of roads). The study also presents information on the impacts of debris torrents to riparian areas.
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Roth, L. F., Shaw, C. G., Rolph, L. 1977. Marking Ponderosa Pine to Combine Commercial Thinning and Control of Armillaria Root Rot. Journal of Forestry: 644-647.
Abstract: Root rot caused by Armillaria mellea (Vahl, ex. Fr.) Quel, in natural ponderosa pine (Pinus ponderosa Laws.) can be reduced by removing diseased trees during commercial thinning. Critically situated infected trees are pushed out to interrupt vegetative spread among the roots and to kill the fungus through exposure.
Rudinsky, J. A. 1962. Ecology of Scolytidae. Annual Review of Entomology 7: 327-348.
Summary: An overview of the Scolytidae family, which includes bark beetles and ambrosia beetles, organisms that have inflicted significant ecological and economic damage on forests throughout the world. Included is a discussion of the ecological groups of Scolytidae, the factors influencing larval development, dispersal mechanisms, and population dynamics.
Scharpf, R. F. 1993. Diseases of Pacific Coast Conifers. Agriculture Handbook 521. Washington, DC: U.S. Department of Agriculture Forest Service.
Abstract: This handbook provides basic information needed to identify the common diseases of Pacific Coast conifers. Host, distribution, disease cycles, and identifying characteristics are described for more than 150 diseases, including cankers, diebacks, galls, rusts, needle diseases, root diseases, mistletoes, and rots. Diseases in which abiotic factors are involved are also described. For some gorups of diseases, a descriptive key to field identification is included.
Schowalter, T. D., Hargrove, W. W. and Crossley, D. A. 1986. Herbivory in Forested Ecosystems. Ann. Rev. Entomol. 31: 177-196.
Abstract: A review of information on the process of herbivory and the nature of insect/plant relationships, focusing on the activities of foliage-consuming (folivorous) and sap-feeding insects. The purpose of the article is to integrate the biochemical and ecosystem views of herbivory, emphasizing factors that influence herbivory in forest ecosystems and the consequences of herbivory at the tree and ecosystem levels of resolution.
Schuett-Hames, D., Conrad, R., Pleus, A., et al. 1999a. Timber Fish & Wildlife Monitoring Program Method Manual for the Salmonid Spawning Gravel Composition Survey. TFW-AM9-99-006, DNR 108. Olympia, WA: Washington Department of Natural Resources.
Abstract: The Timber Fish Wildlife (TFW) monitoring Program method manual for the Salmonid Spawning Gravel Composition (SG Comp) Survey provides a standard method of the assessment and monitoring of salmonid spawning gravel composition. The method is divided into sample inventory, collection, and processing sections. The inventory process ensures that samples from either riffle crests or gravel patch
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features are representative of spawning gravel composition on a stream segment scale. There are two options for processing samples through a standard set of sieves. The relatively quicker volumetric method measures the volume (milliliters), and the gravimetric method measures the weight (grams), of sample particles by size class. TFW data management services provides basic data analysis for spawning gravel samples such as calculating the percentage of particles less than 0.85 millimeters ("fine sediments" - volumetric equivalent) and the geometric mean diameter (gravimetric equivalent).
The introduction section describes the purpose of the SG Comp Survey, reviews scientific background information, and describes the services provided by the TFW Monitoring Program. Following the introduction, sections are presented in order of survey application including: study design, sample inventory, sample collection, sample processing, survey documentation, data management, and references. An extensive appendix is also provided that includes an equipment and resource contact list, copy masters of field forms, examples of completed field forms, standard field and vehicle gear checklist, sample bucket data tracking slips, database management examples, and a random number table.
_____. 1999b. Timber Fish & Wildlife Program Method Manual for the Salmonid Spawning Gravel Scour Survey. TFW-AM9-99-008, DNR 110. Olympia, WA: Washington Department of Natural Resources.
Abstract: The TFW Monitoring Program method manual for the Salmonid Spawning Gravel Scour Survey provides a standard method for assessing and monitoring changes in the depth, frequency and distribution of scour on a stream segment scale. Segments for monitoring scour are selected on the basis of one of three monitoring objectives. Information on frequency and depth of scour is useful when there is a need to evaluate the effect of scour on salmonid incubation, such as in the case of sensitive or declining stocks. It is also useful for evaluating the response of stream channels to changes in peak flow discharge, sediment input, or large woody debris loading due to land-use activities or natural events.
Once objectives are identified and segments have been selected, the spawning gravel is inventoried and categorized by spawning habitat type. Then cross sections are established in a sub-sample of randomly selected spawning gravel areas representing each habitat type. Scour monitors are inserted in potential spawning gravel along each cross section, bed elevations are surveyed and substrate particle size is documented with a pebble count. Data on depth of scour, changes in bed elevation, and substrate particle size are collected after each storm event during the monitoring period. Peak flow discharge is documented. Scour data are analyzed in the TFW Monitoring database, which generates reports that characterize the depth, frequency and distribution of scour by cross section and spawning habitat type. Scour data are interpreted in the context of peak discharge events.
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The remainder of section 1 describes the purpose of the Scour Survey, reviews scientific background information, and describes the cooperator services provided by the TFW Monitoring Program. The following sections are presented in order of survey application including: study design, pre-survey preparation, survey method, post-survey documentation, data management, and references. An extensive appendixes includes: copy masters of field forms; examples of completed field forms; scour monitor and inserter size and construction detail instructions; a sample size calculation matrix; a sample site selection worksheet example; a standard field and vehicle gear checklist; and a data management example.
Schuett-Hames, D., Pleus, A. E., Rashin, E., et al. 1999. Timber Fish & Wildlife Monitoring Program Method Manual for the Stream Temperature Survey. TFW- AM9-99-005, DNR 107. Olympia, WA: Washington Department of Natural Resources.
Abstract: The TFW Monitoring Program method manual for the Stream temperature (TEMP) Survey provides a standard method for assessing and monitoring the quantity and quality of stream temperature and thermal reach characteristics. The TEMP Survey provides a standard method for conducting annual maximum temperature monitoring studies to accomplish a variety of objectives, including assessment and monitoring of water temperature changes associated with land management activities, characterization and monitoring of stream reaches of special interest due to their importance for salmonid habitat or water quality, or characterization of temperature regimes throughout a watershed.
The monitoring approach involves collection of water temperature data at temperature stations, and optional characterization of channel and riparian conditions in thermal reaches immediately upstream of the temperature stations to identify factors affecting water temperature. Procedures cover the use of data logger and maximum/minimum temperature instruments for collecting water temperature data. Water temperature data are analyzed in the TFW Monitoring Program database and reports are generated that characterize the temperature regime for each temperature station daily, weekly, monthly and project basis. Cases where water quality standards have been exceeded are identified. Additional information can be collected on factors that affect the maximum water temperature regime, including air temperature, canopy closure (shade), reach elevation, stream width and depth, gradient, channel morphology and groundwater inflow.
The remainder of the introduction section describes the purpose of the TEMP Survey, reviews scientific background information, and describes the cooperator services provided by the TFW Monitoring Program. Following the introduction, sections are presented in order of survey application including: study design, pre- survey preparation, survey methods, post-survey documentation, data management, and references. An extensive appendix is also provided that includes: copy masters of field forms; examples of completed field forms; a standard field and vehicle gear
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checklist; data management examples; and a copy of the Washington State Water Quality Standards classification list.
Schuett-Hames, D., Pleus, A. E., Smith, D. 1999. Timber Fish & Wildlife Program Method Manual for the Salmonid Spawning Habitat Availabilty Survey. TFW-AM9-99-007, DNR 109. Olympia, WA: Washington Department of Natural Resources.
Abstract: The TFW Monitoring Program method manual for the Salmonid Spawning Habitat Availability (SHA) Survey provides a standard method for the assessment and monitoring of available salmonid spawning habitat. The criteria used to determine spawning habitat includes substrate particle size, substrate depth, water depth, water velocity, and surface area coverage. The SHA Survey has two methods for estimating the amount of spawning habitat on the TFW stream segment scale. The transect method uses dominant substrate information collected along systematically placed transects to estimate the total surface area of potential spawning habitat within the bankfull and wetted channels. The patch method provides detailed information on the surface area and distribution of individual spawning habitat patches within the wetted channel. Monitoring objectives and timing of surveys are used to select whether one or both survey methods are applied.
The remainder of the introduction section describes the purpose of the SHA Survey, reviews scientific background information, and describes the cooperator services provided by the TFW Monitoring Program. Following the introduction, sections are presented in order of survey application including: study design, pre-survey preparation, stream discharge, survey methods, post-survey documentation, data management, and references. An extensive appendix is also provided that includes: field form copy masters; examples of completed field forms; a field code sheet; data management examples, and a standard field and vehicle gear checklist.
Swetnam, T. W., Allen, C. D. and Betancourt, J. L. 1999. Applied Historical Ecology: Using the Past to Manage for the Future. Ecological Applications 9(4): 1189-1206.
Abstract: Applied historical ecology is the use of historical knowledge in the management of ecosystems. Historical perspectives increase our understanding of the dynamic nature of landscapes and provide a frame of reference for assessing modern patterns and processes. Historical records, however, are often too brief or fragmentary to be useful, or they are not obtainable for the process or structure of interest. Even where long historical time series can be assembled, selection of appropriate reference conditions may be complicated by the past influence of humans and the many potential reference conditions encompassed by nonequilibrium dynamics. These complications, however, do not lessen the value of history; rather they underscore the need for multiple, comparative histories from many locations for evaluating both cultural and natural causes of variability, as well as for characterizing the overall dynamical properties of ecosystems. Historical knowledge may not simplify the task of setting management goals and making decisions, but 20th century
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trends, such as increasingly severe wildfires, suggest that disregarding history can be perilous.
We describe examples from our research in the southwestern United States t illustrate some of the values and limitations of applied historical ecology. Paleoecological data from packrat middens and other natural archives have been useful for defining baseline conditions of vegetation communities, determining histories and rates of species range expansions and contractions, and discriminating between natural and cultural causes of environmental change. We describe a montane grassland restoration project in northern New Mexico that was justified and guided by an historical sequence of aerial photographs showing progressive tree invasion during the 20th century. Likewise, fire scar chronologies have been widely used to justify and guide fuel reduction and natural fire reintroduction in forest. A southwestern network of fire histories illustrates the power of aggregating historical time series across spatial scales. Regional fire patterns evident in these aggregations point to the key role of interannual lags in responses of fuels and fire regimes to the El Nino-- Southern Oscillation (wet/dry cycles), with important implications for long-range fire hazard forecasting. These examples of applied historical ecology emphasize that detection and explanation of historical trends and variability are essential to informed management.
Varty, I. W. 1975. Forest Spraying and Environmental Integrity. The Forestry Chronicle: 146-149.
Summary: An overview of the environmental consequences of chemical insecticide spraying as a means of managing pest outbreaks in Canadian forests. Presents both the positive and negative consequences of such spraying, and answers several questions regarding the regulatory oversight of spraying activities, its impacts to fish and wildlife, and its role in maintaining a balanced ecological system.
Wallner, W. E. 1987. Factors Affecting Insect Population Dynamics: Differences Between Outbreak and Non-Outbreak Species. Ann. Rev. Entomol. 32: 317-340.
Abstract: A review and comparison of the factors affecting insect population dynamics. Emphasis is placed upon phytophagous insects of perennial plant habitats, since extended temporal observations are essential for describing endemic populations and the processes by which populations change from latent to endemic. The voluminous literature on insects from varied habitats dictates that this review be focused on: (a) how ecological factors such as natural enemies, weather, host, and site of perennial plant habitats (mainly forest) influence endemic and epidemic insect dynamics; and (b) how heritable features of individual populations are important in differentiating between endemic insect and epidemic pests.
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Williams, G. W. 1994. References on the American Indian Use of Fire in Ecosystems. Unpublished manuscript.
Summary: A bibliography that lists published works on Native Americans and their use of fire. Includes a brief introduction and documents several reasons Native Americans used fire – primarily to promote diversity of habitats.
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Supporting Studies
Aho, P. E. 1974. Defect Estimation for Grand Fir in the Blue Mountains of Oregon and Washington. Research Paper PNW-175. Portland, OR: U.S. Department of Agriculture Forest Service.
Summary: Management of grand fir is difficult because of excessive defect, mainly decay. Two methods had been used to estimate the extend of defect. However, after these methods were developed, cull rules for true firs changed, requiring a revision in present board-foot, defect-indicator percentages. This paper reports on the revised grand fir defect indicator percentages, with the aim of making indicator length deduction factors more readily available.
Barrett, J. W. and Roth, L. F. 1985. Response of Dwarf Mistletoe-Infested Ponderosa Pine to Thinning: 1. Sapling Growth. Research Paper PNW-330. Portland, OR: U.S. Department of Agriculture Forest Service.
Abstract: Observations of thinned ponderosa pine infested with dwarf mistletoe over a 17-year period suggests that on average or better sites most infested stands can be managed to produce usable wood products in reasonable time, if trends found in juvenile stands continue.
Bork, J. L. 1984. Fire History in Three Vegetation Types on the Eastern Side of the Oregon Cascades. Ph.D. diss., Oregon State University.
Abstract: Historic fire return intervals in three different vegetation types dominated by ponderosa pine (Pinus ponderosa Laws.) were determined using fire scarred trees. Dendrochronological techniques were used to achieve accuracy in dating fire scars on samples colleted from six 40 acre plots established in each site. Mean fire return intervals (MFRI) differed fro site and plots within each site; Pringle Butte site showed the shortest MFRI of 4 years with an average of 11 years for individual plots, Cabin Lake site had a 7 year MFRI and a 24 year MFRI for plots, while Lookout Mountain site had a MFRI of 8 years and 16 years for plots. The overall average for plots incorporates all of the data for the site but uses a 40 acre plot mean to determine length of time required for fire to return to the same location, giving a more accurate indication of MFRI in a given stand. The plot mean may be the most useful way of expressing the data. Basal area and understory vegetation were found to be useful for predicting MFRI. Tree-ring chronologies from the three sites were examined to determine their suitability for climatic interpretation. Statistics show low mean sensitivities, high serial correlations and low variance for all trees and cores, suggesting that chronologies are of limited use for climatic analysis. However, climatic information was found. Growth patterns in sites show similar years for drought and high precipitation. Long-term trends were not evident at Cabin Lake or Lookout Mountain. Pringle Butte provided the chronology most useful for estimating climatic history, with 3 long periods of slow growth, 1900-1980, 1710-1790, and 1590-1640. RIPARIAN DISTURBANCE REGIMES IN EASTERN WASHINGTON Concurrent Technologies Corporation - 207 -
Bren, L. J. 1995. Aspects of the Geometry of Riparian Buffer Strips and Its Significance to Forestry Operations. Forest Ecology and Management 75: 1-10.
Abstract: A stream buffer strip is an area within a defined distance from a stream in which land use activities are restricted for stream protection purposes. This study used a sophisticated Geographic Information System to examine the extent, distribution, and boundary properties of land defined by buffer strips of differing widths. The prototype catchment studied was the mountainous 65km2 Tarago River catchment in eastern Victoria. The West Tarago River is a fourth-order stream network. This was accurately delineated using the topographic map supplemented by high quality aerial colour transparencies. This showed that the map had inadequate detail of smaller streams. The streams had a branching network with an overall fractal dimension (measure of complexity) of 1.75, although the fractal dimension of the individual stream reaches was only slightly greater than one. The area of land occupied by buffers increased substantially with increasing width of buffers, with 95 percent of the catchment occupied by buffers of 300 m width. As buffer width increased to 100 m, many areas became entrapped by buffers and hence became effectively inaccessible. Individual boundaries reached their greatest complexity at 10 m buffer width, but the buffer/non-buffer network achieved greatest complexity at 100 m buffer width. Small buffers had a very high perimeter/area ratio. As buffer width increased the perimiter/area ratio of non-buffer areas slowly increased, reflecting that non-buffer areas were becoming smaller and more fragmented.
Chojnacky, D. C., Bentz, B. J., Logan, J. A. 2000. Mountain Pine Beetle Attack in Ponderosa Pine: Comparing Methods for Rating Susceptibility. Research Paper RMRS-RP-26. Ogden, UT: U.S. Department of Agriculture Forest Service.
Abstract: Two empirical methods for rating susceptibility of mountain pine beetle attack in ponderosa pine were evaluated. The methods were compared to stand data modeled to objectively rate each sampled stand for susceptibly to bark-beetle attack. Data on bark-beetle attacks, from a survey of 45 sites throughout the Colorado Plateau, were modeled using logistic regression to estimate the probability of attack on individual trees from tree and stand variables. The logistic model allowed flexibility to easily scale results up to a stand level for comparison to the empirical methods. The empirical methods, developed by Munson and Anhold, most closely correlated to the logistic regression results. However, the Munson/Anhold method rated all 45 study sites as either moderately or highly susceptible to bark-beetle attack, which raises concern about its lack of sensitivity. Future work on evaluating risk of bark-beetle impact should consider more than stand characteristics.
Cochran, P. H. and Barrett, J. W. 1998. Thirty-Five-Year Growth of Thinned and Unthinned Ponderosa Pine in the Methow Valley of Northern Washington. PNW-RP-502. Portland, OR: U.S. Department of Agriculture Forest Service.
Abstract: It is commonly expected that self-thinning will maintain small-diameter stands at near-normal densities and allow dominant trees to grow reasonably well.
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Such self-thinning did not occur in the unthinned plots in a thinning study in the Methow Valley of northern Washington, even though there was some suppression- caused mortality. A shift from suppression-caused mortality to insect-caused mortality took place when quadratic mean diameters (QMDs) reached 7 inches. Thinning to spacings wider that 9.3 feet reduced growth of both basal area and cubic volume per acre but greatly increased growth of board-foot volume per acre, and diameter and height growth. Periodic annual increments of cubic volume and QMD are curvilinearly related to stand density index. Growth of the largest 62 trees per acre was clearly reduced by the presence of smaller trees in the stand. Density management is necessary to produce reasonable growth rates of even the largest trees in the stand and to speed the development of mid-seral conditions.
Cochran, P. H. and Dahms, W. G. 2000. Growth of Lodgepole Pine Thinned to Various Densities on Two Sites with Differing Productivities in Central Oregon. PNW-RP- 520. Portland, OR: U.S. Department of Agriculture Forest Service.
Abstract: Plots in two natural lodgepole pine (Pinus contorta Dougl. Ex Loud.) stands with differing productivities were repeatedly thinned to one of five growing- stock levels (GSLs). Bole area was used to define GSLs. A linear relation between stand density index (SDI) and bole area was found after each thinning on the highly productive site, but the slope of this relation decreased with successive thinning as trees grew larger. On the site with intermediate productivity, the upper limit for bole area was higher and a curvilinear SDI-bole area relation occurred. A constant bole area level probably does not represent the same competition level across a range of tree sizes. Low incidence of mortality caused by mountain pine beetle (Dendroctonus ponderosae Hopkins) occurred at SDIs below 170 for both sites. Concave curvilinear decreases in diameter growth occurred with increasing GSLs. Significant decreases in height growth with increasing GSLs were not detected. A convex curvilinear increase in gross basal-area growth and cubic-volume growth took place with increasing GSLs. Gross total cubic-volume PAIs increased with increasing SDIs for both sites until stand densities reached 95 percent of the normal stand SDI. These cubic-volume PAI-SDI curves then flattened with increasing SDIs. Maximum cumulative net cubic-volume (total and merchantable) and board-foot yields were produced at the intermediate growing-stock level at the high site. Little apparent difference in these yields occurred among the four highest GSLs at the intermediate site. Net total cubic-volume yield was higher for the three highest GSLs than net yields for unmanaged stands from yield tables at comparable sites and ages. These studies have not continued long enough to determine the approximate age of culmination of net mean annual cubic-or board-foot volume increments. Ponderosa pine (Pinus ponderosa Dougl. Ex Law.) outgrew lodgepole pine for the range of stand ages on the highly productive site where the growth of both species was examined (33 to 58 years). Ponderosa pine should not be planted on lodgepole pine sites on flats and basins, however, because ponderosa pine is subject to radiation frost damage. Early spacing control coupled with later commercial thinning to keep stand densities between SDI 114 and SDI 170 should reduce mortality considerably, allow most of the wood produced to be captured by merchantable trees, and greatly increase
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quadratic mean diameters and live crown ratio over unmanaged stands at the same age. These stands would be more pleasing visually, and their rotation ages may be longer.
Cochran, P. H. and Seidel, K. W. 1999. Growth and Yield of Western Larch Under Controlled Levels of Stocking in the Blue Mountains of Oregon. PNW-RP-517. Portland, OR: U. S. Department of Agriculture Forest Service.
Abstract: Repeated thinning to five growing-stock levels resulted in widely differing tree sizes and volumes per acre after 30 years. Largest trees but the least cubic- volume yield per acre were produced in the heaviest thinning level, whereas highest board-foot yields were found in intermediate thinning levels. Partial defoliation by larch casebearer (Coleophora laricella Hubner), drought, and top damage from ice occurred, and site trees grew less in height than expected during the 30-year study. Curvilinear increases in periodical annual increments of both basal area and cubic volume generally occurred with increasing stand density, but increments dropped off at the highest stand densities for some periods. Anticipated patterns for these increments were found after fitting a model that included stand density index, height increments of site trees, and dummy variables for periods as independent variables. Heavy thinning did not increase the age of culmination of cubic-volume mean annual increment as expected. Thinning stands of larch to densities as low as 50 percent of "normal" results in little loss of basal-area growth, a moderate loss in volume production, and a large increase in tree diameter. Thinning is necessary in many larch stands to maintain vigorous, rapidly growing trees. Thinning levels will greatly affect the appearance of future stands.
Cochran, P. H., Geist, J. M., Clemens, D. L., et al. 1994. Suggested Stocking Levels for Forest Stands in Northeastern Oregon and Southeastern Washington. PNW-RN-513. Portland, OR: U.S. Department of Agriculture Forest Service.
Abstract: Catastrophes and manipulation of stocking levels are important determinants of stand development and the appearance of future forest landscapes. Managers need stocking level guides, particularly for sites incapable of supporting stocking levels presented in normal yield tables. Growth basal area (GRA) has been used by some managers in attempts to assess inherent differences in site occupancy but rarely has been related to Gingrich-type stocking guides. To take advantage of information currently available, we used some assumptions to relate GBA to stand density index (SDI) and then created stocking level curves for use in northeastern Oregon and southeastern Washington. Use of these curves cannot be expected to eliminate all insect and disease problems. Impacts of diseases, except dwarf mistletoe (Arceuthobium campylopodum Engelm.), and of insects, except mountain pine beetle (Dendroctonus ponderosea Hopkins) and perhaps western pine beetle (Dentroctonus brevicomis LeConte), may be independent of density. Stands with mixed tree species should be managed by using the stocking level curves for the single species prescribing the fewest number of trees per acre.
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Cole, W. E. and Cahill, D. B. 1976. Cutting Strategies Can Reduce Probabilities of Mountain Pine Beetle Epidemics in Lodgepole Pine. Journal of Forestry: 294-297.
Abstract: Mountain pine beetle attacks in lodgepole pine stands are generally concentrated on trees of large diameter and thick phloem, and brood production is greatest within such trees. Three lodgepole stands infested at various epidemic levels were sampled in 1971 and pre-epidemic diameter and phloem thickness distributions were estimated. Estimates of residual food supplies for beetles when partial cutting levels were applied to the data show that managing the stands so that trees did not reach 10 inches in dbh would have substantially lowered the probabilities that epidemics would develop.
Entry, J. A., Cromack, K., Kelsey, R. G., et al. 1991. Response of Douglas-Fir to Infection by Armillaria ostoyae After Thinning or Thinning Plus Fertilization. Phytopathology 81: 682-689.
Abstract: Second -growth stands of Douglas-fir (Pseudotsuga menziesii) were thinned to a 5- x 5-m spacing (TT); additional plots were thinned and fertilized once with 360 kg of N (as urea) per hectare (TF). An unthinned, unfertilized stand (UT) served as a control . Ten years after treatment, trees were inoculated with two isolates of Armillaria ostoyae. Trees receiving the TF and TT treatments produced greater diameter growth, leaf area, and wood production per square meter of leaf area per year than did those under the UT treatment. Rates of infection by A.ostoyae were highest in trees that received the TF and lowest in trees that received the TT treatment. Concentrations of sugar, starch and cellulose in root bark tissue were highest in trees receiving the TF treatment and lowest in trees receiving the TT treatment. Concentrations of lignin, phenolics and protein-precipitable tannins were highest in root bark from TT trees and lowest in root bark from TF trees. Biochemical parameters of root bark tissue were regressed with incidence of infection; coefficients of determination (r2) ranged from 0.07 (starch) to 0.57 (phenolic compounds). Ratios of the energetic costs of phenolic and of lignin degradation to the energy available from sugars (Epd:Eas and Eld::Eas) were correlated with incidence of infection (r2=0.77 and 0.70, respectively). Thinning combined with fertilization may predispose P. menziesii trees to infection by A. ostoyae by lowering concentrations of defensive compounds in root bark and increasing the energy available to the fungus and degrade them.
Everett, R. L., Camp, A. E. and Schellhaas, R. 1995. Building a New Forest with Fire Protection in Mind. Paper presented at the Fire Protection Working Group Technical Session at the SAF National Convention, October 28 – November 1, Portland, MA.
Abstract: Dry pine sites of the Inland West are becoming increasingly susceptible to catastrophic fire events as the disparity between historical and current disturbance regimes and associated vegetation conditions increases. Following catastrophic fires on public lands, management should capitalize on forest remnants to provide future forest legacies for logs and snags, but may need to reduce future fire hazard from an
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excess of dead and down trees or accept the additional fire risk. Examples from the 1994 Tyee Fire and nearby areas on the Wenatchee National Forest demonstrate how creating new forests with reduced hazard for catastrophic fires can be accomplished while simultaneously achieving vegetation characteristics required to meet public expectations on an array of specific land allocations. Vegetation characteristics that support emphasized uses within land allocations need to be evaluated for synchrony with the inherent disturbance regimes of the area. We suggest that recognizing and managing disturbances is key to protecting emphasized uses, integrating adjacent land use allocations, restoring the continuity of inherent disturbance regimes among allocations, and reducing future hazard to catastrophic fire events.
Ferguson, D. E. and Adams, D. L. 1980. Response of Advance Grand Fir Regeneration to Overstory Removal in Northern Idaho. Forest Science 26(4): 537-545.
Abstract: A mathematical model predicting height growth for released grand fir regeneration is presented. Data used to develop the model indicate that response to release depends on tree characteristics and site conditions interacting with physiological shock. Tall trees which are equally or more suppressed by the overstory do not respond as well as short trees. Logging damage decreases response. Recommendations for releasing stands of advance grand fir and guidelines for thinning released stands are provided.
Filip, G. M. 1989. Incidence and Biology of Root and Stem Decay Fungi in Thinned Conifer Stands, Oregon and Washington, USA. In Proceedings of the Eighth International Conference on Root and Butt Rots. Uppsala, Sweden: Swedish University of Agricultural Sciences.
Abstract: Stumps resulting from thinning operations serve as infection foci for root pathogens such as Phellinus weirii, Armillaria ostoyae, Heterobasidion annosum, and Ceratocystis wageneri in Oregon and Washington. Heterobasidion annosum has been reported in thinning stumps of Tsuga hertophylla, Pinus ponderosa, and Larix occidentalis but is probably most abundant in Abies grandis and other species of Abies. Armillaria ostoyae has been identified as causing severe damage in central Washington and is presumed to be responsible for most damage formerly attributed to A. mellea through Oregon and Washington. Heterobasidion annosum has been reported in residual trees in thinned stands of Tsuga heterophylla, Abies grandis, and A. concolor. Armillaria ostoyae has been reported in residual trees in thinned stands of Pinus ponderosa, Pseudotsuga menziesii, Abies procera and A. magnifica. Mortality caused by Ceratocystis wageneri is associated primarily with stands of Psuedotsuga menziesii that have been thinned or disturbed. Infection of residual trees by root pathogens is mainly via adjacent infected stumps.
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_____. 1993. Further Studies on the Effects of Thinning and Harvesting of Conifers on Armillaria ostoyae and Heterobasidion annosum in Oregon, USA. In Proceedings of the Eighth International Conference on Root and Butt Rots. Uppsala, Sweden: Swedish University of Agricultural Sciences.
Abstract: Although thinning and partial harvesting have been used in Oregon, USA, for decades, their effects on root pathogen/host interactions are not well known. Precommercial thinning has been shown to have no significant effect on crop-tree mortality caused by Armillaria ostoyae in several conifer species in central Oregon. Thinning with nitrogen fertilizing significantly decreased the percentage of stem decay caused by Heterobasidion annosum in Abies grandis in southern Oregon. Neither season of harvesting nor stump size significantly affected the amount of stump decay caused by H. annosum in A. grandis stumps of trees cut 5 to 10 years earlier in northeastern Oregon.
Filip, G. M., Fitzgerald, S. A., Ganio, L. M. 1999. Precommercial Thinning in a Ponderosa Pine Stand Affected by Armillaria Root Disease in Central Oregon: 30 Years of Growth and Mortality. Western Journal of Applied Forestry 14(3): 144-148.
Abstract: A 30-yr old stand of ponderosa pine was precommercially thinned in 1966 to determine the effects of thinning on tree growth and mortality caused by Armillaria root disease in central Oregon. After 30 yr, crop tree mortality was significantly (P=0.03) less in thinned plots than in unthinned plots. Tree diameter growth was not significantly (P=0.17) increased by thinning. Crop-tree basal area/ac growth was significantly (P=0.03) greater in thinned plots. Apparently from a root disease perspective, precommerical thinning of pure ponderosa stands significantly decreases the incidence of crop-tree mortality after 30 yr and significantly increases basal area/ac growth but not individual tree diameter growth. Recommendations for thinning based on stand density index (SDI) are given.
Filip, G. M., Schwandt, J. W. and Hagle, S. K. 1990. Estimating Decay in 40- to 90-Year- Old Grand Fir Stands in the Clearwater Region of Northern Idaho. PNW-RP-421. Portland, OR: U.S. Department of Agriculture Forest Service.
Abstract: The fir decay equation for Oregon and Washington was used to predict stem decay in 12 grand fir (Abies grandis )Dougl. Ex D. Don) Lindl.) stands in the Clearwater region of northern Idaho. These 12 stands represented a range in geographic and stand characteristic variation. All 12 observed decay percentages were within their associated 95-percent predication intervals. We therefore concluded that the fir decay equation for Oregon and Washington can be used to estimate stem decay in 40-to-90 year-old grand firs stands in the Clearwater region. Information also is presented on decay biology, hazard-rating techniques, and stand management recommendations.
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Goheen, D. J. and Hansen, E. M. 1978. Black Stain Root Disease in Oregon and Washington. Plant Disease Reporter 62(12): 1098-1102.
Abstract: Surveys and collected observations indicate that black stain root disease, caused by Verticicladiella wagenerii, is fairly common and widely distributed in western Oregon and Washington. Concern about the possible importance of the disease is mounting. Douglas-fir is the major host, but ponderosa pine and mountain hemlock also have been found infected. The disease is usually found in small, fairly discrete infection centers and causes rapid tree decline and death. It frequently predisposes trees to attack by insects and infection by Armillaria mellea.
Harrington, T. C., Cobb, F. W. and Lownsbery, J. W. 1985. Activity of Hylastes nigrinus, a Vector of Verticicladiella wageneri, in Thinned Stands of Douglas-Fir. Can. J. For. Res. 15: 519-523.
Abstract: Live adults of Hylastes nigrinus (Mann.), a root-feeding bark beetle suspected of being a vector of Verticicladiella wageneri Kendr., were trapped in infection centers of black stain root disease and allowed to feed on seedlings of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) in the greenhouse. Three of 22 beetles that were artificially contaminated with conidia of V. wageneri introduced the pathogen into seedlings. One of 47 seedlings infested with pairs of H. nigrinus that were not artificially contaminated became infected with V. wageneri. The activity of H. nigrinus in thinned plots at three sites near the North Coast of California was monitored with sticky traps. In 1981, 100 adults were trapped in plots mechanically thinned on 13 April 1981. Only two H. nigrinus were trapped in unthinned, control plots. Twenty-two adults were trapped in plots chemically thinned by the injection of cacodylic acid. In 1982, as many or more adults were trapped in plots that were thinned after the seasonal peak of H. nigrinus in 1981 as in plots that were freshly thinned. Roots of living Douglas-fir trees examined in a mechanically thinned plot had feeding wounds similar to those described as feeding wounds made by H. nigrinus. Roots of living Douglas-fir in an unthinned plot had no evidence of insect feeding. Although no black stain was found associated with feeding wounds on living trees, the previously noted association of black stain root disease in thinned stands may still be due to an increased activity of H. nigrinus.
Hawksworth, F. G., Johnson, D. W., Geils, B. W. 1987. Sanitation Thinning in Young, Dwarf Mistletoe-Infested Lodgepole Pine Stands. In Management of Subalpine Forests: Building on 50 Years of Research. Fort Collins, CO: U.S. Department of Agriculture Forest Service.
Abstract: Dwarf mistletoe (Arceuthobium americanum Nutt. ex Engelm.) is the most serious tree disease agent of lodgepole pine in the Rocky Mountains. This parasite occurs on more than half of the 2 million acres of commercial lodgepole pine forests in the Central Rocky Mountains, and causes an annual volume loss of more than 15 million cubic feet. Dwarf mistletoes are one of the few forest diseases that can be effectively controlled by silvicultural means (Johnson and Hawksworth 1985).
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However, some early cultural practices actually intensified the problem. For example, harvest operations that left infected residual trees provided ideal conditions for maximum spread and intensification of the disease into young stands.
Thousands of acres of lodgepole pine in the Rocky Mountain Region were partially logged in the 1950's and 1960's and many mistletoe-infected but non-merchantable trees were left standing. These trees now provide a serious source of infection for the young, naturally regenerated stands that have become established beneath them. Sales contracts now call for removal of all infected trees in cutting areas, but vast problem areas of infected reproduction remain in older sales areas.
Kipfmueller, K. F. and Swetnam, T. W. 2000. Fire-Climate Interactions in the Selway- Bitterroot Wilderness Area. In Wilderness Ecosystems, Threats, and Management. (RMRS-P-15). Tucson, AZ: U.S. Department of Agriculture Forest Service.
Abstract: Tree-ring reconstructed summer drought was examined in relation to the occurrence of 15 fires in the Selway-Bitterroot wilderness Area (SBW). The ten largest fire years between 1880 and 1985 were selected from historical fire atlas data; five additional fire years were selected from a fire history completed in a subalpine forest within the SBW. Results of the analysis indicate summers during the fire year were significantly (p<0.001) drier than average conditions. The summer preceding the fire year tended to be drier than average, but results were not statistically significant (p>0.05). A significant (p<0.05) wet year occurred four years prior to fire occurrence in the SBW. Further research which examines fire-climate interactions differentiated by forest type may provide an improved understanding of the dynamics between fire and climate.
Knutson, D. and Tinnin, R. 1986. Effects of Dwarf Mistletoe of the Response of Young Douglas-Fir to Thinning. Can. J. For. Res. 16: 30-35.
Abstract: Four sites from two forests were examined to determine the effect of various levels of infection by Arceuthobium douglasii on the growth of Pseudotsuga menziesii in precommerically thinned stands. We found less than 1 percent mortality among the trees that we examined. Changes in level of infection did occur, we estimate that changes to levels of infection sufficient to cause significant reductions in diameter growth occurred among 19 percent of the infected trees that we studied. Height growth was significantly reduced in both forests, while diameter growth was reduced by infection in one forest. Trees of lower infection rating (dwarf mistletoe rating 0-2) showed a significant increase in radical growth following thinning in both forests, while more heavily infected trees (dwarf mistletoe rating 5 to 6) did not. Trees that were heavily infected and had spike tops consistently showed significant reductions in diameter growth in both forests.
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Lenihan, J. M. and Neilson, R. P. 1995. Canadian Vegetation Sensitivity to Projected Climatic Change at Three Organizational Levels. Climatic Change 30: 57-73.
Abstract: The potential equilibrium response of Canadian vegetation under two double-CO2 climatic scenarios was investigated at three levels in the vegetation mosaic using the rule-based Canadian Climate-Vegetation Model (CCVM) and climatic response surfaces. The climatic parameters employed as model drivers (I.e.degree-days, minimum temperature, snowpack, actual evapotranspiration, and soil moisture deficit) have a more direct influence on the distribution of vegetation than those commonly used in equilibrium models. Under both scenarios, CCVM predicted reductions in the extent of the tundra and subarctic woodliand formations, a northward shift and some expansion in the distributions of boreal and the temperate forest, and an expansion of the dry woodland and prairie formations that was especially pronounced under one of the scenarios. Results of the response surface analysis suggest the potential for significant changes in the probability of dominance for eight boreal tree species. A dissimilarity coefficient was used to identify forest- types under the future climatic scenarios that were analogous to boreal forest-types derived from cluster analysis of the current probabilities of species dominance. All of the current forest-types persisted under the doubled-CO2 scenarios, but 'no-analog' areas were also identified within which an empirically derived threshold of the distance coefficient was exceeded. Maps showing the highest level in the vegetation hierarchy where change was predicted suggest the relative impact of the response under the two climatic scenarios.
Mitchell, R. G. and Buffam, P. E. 2001. Patterns of Long-Term Balsam Woolly Adelgid Infestations and Effects in Oregon and Washington. Western Journal of Applied Forestry 16(3): 121-126.
Abstract: The balsam woolly adelgid (Adelges piceae) is an introduced pest discovered damaging grand fir (Abies grandis) in Oregon's Willamette Valley around 1930. In 1955, the insect was found infesting and killing Pacific silver fir (A. amabilis) near Mt. St. Helens in Washington and subalpine fir (A. lasiocarpa) in the Cascade Range in Oregon. In the next 10 yr, the pest dispersed widely throughout western Oregon and Washington, causing significant tree mortality over thousands of acres in the Cascade Range. Observations on trend plots established 35 to 40 yr ago have shown somewhat consistent tends in the patterns of infestation and damage. Infestations and damage were most severe on the best sites and at the lowest elevations where the hosts grown. Tree damage was consistently most severe in the first decade of infestation, but the insect never seemed to disappear from a stand; infestations and tree killing were observed on some plots 40 yr after the initial infestation. An ecological problem with the balsam woolly adeigid is a pattern of attach that I gradually eliminated grand fir from low-elevation landscapes west of the Cascade Range. The adelgid is also removing subalpine fir as a pioneer tree species in many of the important mountain environments.
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Neary, D. G., Klopatek, C. C., DeBano, L. F., et al. 1999. Fire Effects on Belowground Sustainability: A Review and Synthesis. Forest Ecology and Management 122: 51- 71.
Abstract: The overall effects of fire on ecosystems are complex, ranging from the reduction or elimination of aboveground biomass to impacts on belowground physical, chemical and microbial mediated processes. Since a key component of overall ecosystem sustainability occurs belowground, recovery is tied to the soil's physical, chemical and biological functions and processes. Depending on several fire severity measures, changes in belowground components can be either beneficial or deleterious to the entire ecosystem. Low-impact burning can promote a herbaceous flora, increase plant available nutrients, and thing over-crowded forests, all of which can foster healthy systems. Severe fires can often cause changes in successional rates, alter above-and belowground species composition, generate volatilization of nutrients and ash entrainment in smoke columns, produce rapid or decreased mineralization rates, alter C : N ratios, and result in subsequent nutrient losses through accelerated erosion, leaching or denitrification. In addition, changes in soil hydrologic functioning, degradation of soil physical properties, decreases in micro- and macrofauna, and alterations in microbial populations and associated processes can occur. The direct effect of fire on belowground systems is a result of the burning severity, which integrates aboveground fuel loading (live and dead), soil moisture and subsequent soil temperatures, and duration of the burn. The time for recovery of belowground systems will not only depend on the burning intensity and its effect on key ecosystem processes and components, but also on the previous land-use practices. Thus, the impacts of fire on belowground systems can be highly variable and may not be predictable. Our paper is general review of the effects of fire on belowground systems with emphasis placed on the changes in physical, biogeochemical and biological properties of soils and the resulting consequences these changes have for ecosystem sustainability.
Roth, L. F. and Barrett, J. W. 1985. Response of Dwarf Mistletoe-Infested Ponderosa Pine to Thinning: 2. Dwarf Mistletoe Propagation. Research Paper PNW-331. Portland, OR: U.S. Department of Agriculture Forest Service.
Abstract: Propagation of dwarf mistletoe in ponderosa pine saplings is little influenced by thinning overly dense stands to 250 trees per acre. Numerous plants that appear soon after thinning develop from formerly latent plants in the suppressed understory. Subsequently, dwarf mistletoe propagates nearly as fast as tree crowns enlarge but the rate differs widely among trees. The greatest increase is in the lower third of the tree crown. Parasite abundance had no measurable effect on height growth during 21 years following thinning, and height growth was faster than ascent of the parasite in the crown. Dominant trees that had 28 percent of crown length above the highest dwarf mistletoe plant in 1956 had 62 percent above in 1974.
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Savage, M. and Swetnam, T. W. 1990. Early 19th-Century Fire Decline Following Sheep Pasturing in a Navajo Ponderosa Pine Forest. Ecology 71(6): 2374-2378.
Abstract: The objective of this study is the documentation and interpretation of an unusual fire history in a Southwest ponderosa pine community. The fire-scar record from the Chuska Mountains shows an abrupt and persistent reduction in fire frequency at least four decades earlier than in other parts of the Southwest. The difference in land-use history offers an opportunity (1) to assess the strength of the hypothesis that grazing impacts caused fire-frequency decline in the Southwest, and (2) to assess the relationship between fire decline and shifts in forest structure that occurred soon after.
Scharpf, R. F. and Bega, R. V. 1981. Elytroderma Disease Reduces Growth and Vigor, Increases Mortality of Jeffrey Pines at Lake Tahoe Basin, California. Research Paper PSW-155. Berkeley, CA: U.S. Department of Agriculture Forest Service.
Abstract: A disease of Jeffrey pines (Pinus jeffreyi Grev. And Balf.) at Lake Tahoe Basin, California, caused by Elytroderma disease (Elytroderma deformans) was studied for 7 years after a severe outbreak of the fungus in 1971. Among 607 Jeffrey pines on six plots, about one-half were heavily infected and about one-half were moderately or lightly infected in 1971. No uninfected trees were observed. During the 7-year study, about one-half of the trees remained unchanged in vigor, disease intensity, or both, and about one-half decreased in vigor, became more heavily infected, or both. Of the original 607 trees studied, nearly one-third died before 1978. Average radial growth of surviving trees was less per year after the outbreak than before, and heavily infected trees were growing more slowly than lightly infected trees. Intensity of the disease, however, was not related to stand basal area.
Swetnam, T. W. and Lynch, A. M. 1989. A Tree-Ring Reconstruction of Western Spruce Budworm History in the Southern Rocky Mountains. Forest Science 35(4): 962-986.
Abstract: Tree-ring width chronologies from ten mixed-conifer stands in the Colorado Front Range and New Mexico Sangre de Cristo Mountains were used to reconstruct the timing, duration, and radial growth impacts of past outbreaks of western spruce budworm (Choristoneura occidentalis Freeman). At least nine outbreaks were identified in the stands from 1700 to 1983. Severity and timing of outbreaks was highly variable. The average duration of reduced growth periods caused by budworms was 12.9 years and ranged from 5 to 26 years. The average interval between initial years of successive outbreaks was 34.9 years and ranged from 14 to 58 years. The average maximum and periodic radical growth reductions were 50 percent and 21.7 percent, respectively. There was a relatively long period of reduced budworm activity in the first few decades of the twentieth century, and since that time outbreaks have been markedly more synchronous among the sampled stands. It was hypothesized that the increased synchroneity of outbreaks in the latter half of the twentieth century is due to changes in age structure and species
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composition following harvesting and fire suppression in the late ninetieth and early twentieth centuries.
Tkacz, B. M. and Baker, F. A. 1991. Survival of Inonotus tomentosus in Spruce Stumps After Logging. Plant Disease 75: 788-790.
Abstract: Survival of Inonotus tomentosus was investigated by isolating the fungus from excavated stumps of blue spruce (Picea pungens) and Engelmann spruce (P. englemannii) that had been harvested 9, 13, and 20 yr-old stumps, respectively. The diameter of the smallest roots that yielded I. Tomentosus ranged from 1.3cm (9 yr-old stumps) to 2.5cm (13 and 20 yr-old stumps). The maximum distances that I. Tomentosus was found from the stumps were 3.4, 6.1, and 5.5m for 9, 13, and 20 yr- old stumps, respectively. Isolates of I. Tomentosus from stumps of all ages killed artificially inoculated Engelmann spruce seedlings.
Wicker, E. F. and Hawksworth, F. G. 1991. Upward Advance, Intensification, and Spread of Dwarf Mistletoe in a Thinned Stand of Western Larch. Research Note RM-504. Fort Collins, CO: U.S. Department of Agriculture Forest Service.
Abstract: From 1978 to 1988 western larch (Larix occidentalis) in a thinned, 35- year-old stand in the Coram Experimental Forest, Flathead National Forest in northern Montana, grew an average of 37cm per year in height. This growth rate was over 4 times the rate of upward advance of dwarf mistletoe (Arceuthobium laricis) in these trees, which was only 9cm per year. Currently levels of dwarf mistletoe infection are too low (dwarf mistletoe ratings of only 1 or 2) to reduce tree height or diameter growth, although spread from inoculated trees to previously uninfected ones has occurred at all three spacing levels tested. These findings are discussed in relation to management of dwarf mistletoe in young monocultures of western larch.
Williams, C. B. 1968. Juvenile Height Growth of Four Upper Slope Conifers in the Washington and Nothern Oregon Cascade Range. Research Paper PNW-70. Portland, OR: U.S. Department of Agriculture Forest Service.
Summary: A study that compares the juvenile growth rates of noble fir, Pacific silver fir, Douglas fir, and western white pine on six areas in the Washington and northern Oregon Cascade range. The study found Douglas fir to have the greatest juvenile growth rate and Pacific silver fir the lowest. However, it was noted that these juvenile growth rates may not be sustained throughout the species’ life cycle.
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General References
Alexander, R. R. 1987. Ecology, Silviculture, and Management of the Engelmann Spruce - Subalpine Fir Type in the Central and Southern Rocky Mountains. Agriculture Handbook No. 659. Ft. Collins, CO: U.S. Department of Agriculture Forest Service.
Abstract: The ecological, silvicultural, and managerial knowledge of Englemann spruce (Picea engelmannii Parry ex. Engel.)- subalpine fir (Abies lasiocarpa (Hook.) Nutt.) forests in the central and southern Rocky Mountains is summarized and consolidated in this publication, which updates and expands a previous summary paper on subalpine forests (Alexander 1974). This publication is largely based on past research in the central and southern Rocky Mountains conducted by the Rocky Mountain Forest and Range Experiment Station. While much of the research was done on the Fraser Experimental Forest in central Colorado, other important studies were conducted on permanent and temporary plots on National Forest System Regions 2 and 3. This research was supplemented by research done elsewhere, mostly research done in the northern Rocky Mountains by the Intermountain Forest and Range Experiment Station, and in Alberta and British Columbia by the Canadian Forestry service.
Past research has been directed at perpetuating Engelmann spruce, the most valuable species in the spruce-fir type. Initial studies, started by C. C. Bates and later J. Roeser, Jr., in the early 1900's focused on methods of cutting required to establish regeneration, natural succession, seed production, and physiological requirements. Since 1935, research has broadened to include (1) silvicultural practices and other cultural treatments required to regenerate and grow Engelmann spruce and associated species, (2) seed production and dispersal, (3) the relationship of environmental and biological factors to regeneration, (4) growth and mortality, (5) volume and site determination, (6) stand growth and yield, (7) artificial regeneration, (8) plant community classification, (9) development of understory vegetation, and (10) plant- water relations. IN recent years, efforts have been expanded to include the effects of cultural treatments on other resource requirements.
This publication presents a detailed summary of the (1) ecology and resource, and (2) the silvics, silviculture, and management of spruce-fir forests. Major emphasis is placed on the silviculture and management of old-growth and the establishment of new stands. While not all questions can be answered, this publication provides the comprehensive body of knowledge available for managing spruce-fir forests. It is intended to guide land managers and land use planners who are responsible for prescribing and supervising the application of cultural treatments in the woods.
Binkley, D. and Brown, T. C. 1993. Management Impacts on Water Quality of Forests and Rangelands. Fort Collins, CO: U.S. Department of Agriculture Forest Service.
Abstract: Following an overview of water quality concerns in Chapter 1 and a description of basic forest and rangeland hydrology and water quality process in RIPARIAN DISTURBANCE REGIMES IN EASTERN WASHINGTON Concurrent Technologies Corporation - 220 -
Chapter 2, we summarize what has been learned about the effects of land management practices on nonpoint source pollution at generally small experimental forest and rangeland sites in the United States and Canada. The final chapter describes laws affecting forest and rangeland water quality and the use of best management practices to protect water quality. The quality of water from forested watersheds is typically very good, even on disturbed and managed sites. At most sites, forest practices lead to minimal impacts on water quality and do not seriously impair fish habitat or water supplies. However, at more sensitive sites, special care is required. Existing best management practices, if followed, adequately protect forest water quality. Most states have active programs to promote the use of such practices. Unlike forest practices, impacts of grazing on water quality have received little careful study, and few states have specified best management practices to control grazing impacts. Future study is needed to improve the specification of best management practices for site specific forest situations. A sufficient base of information is also needed to design efficient best management practices for rangelands.
Ferguson, S. A. 1995. Potential Climate Change in Northern North America. In Human Ecology and Climate Change: People and Resources in the Far North, edited by Peterson, D. L., et al. New York: Taylor & Francis.
Summary: An overview that describes the factors that affect global climate and how a warmer climate might affect the regional climatic patterns of North America. Discusses the environmental controls on high-latitude climate (the greenhouse effect, solar radiation, global winds, the ocean, and albedo) and regional climatic patterns in northern North America (including the Arctic coast, the Subarctic interior, and the Alpine transition).
Hansen, P., Pfister, R., Boggs, K., et al. 1995. Classification and Management of Riparian and Wetland Sites in Montana. Missoula, MT: University of Montana, School of Forestry.
Summary: Presents a riparian and wetland vegetation-based ecological site classification for Montana. The classification is designed to provide (1) assistance to resource managers as they identify, describe, communicate about, and manage riparian and wetland areas; (2) describe the general geographic, topographic, pedologic, floristic, and functional features of riparian and wetland ecosystems; (3) describe successional trends and predict vegetative potential on undisturbed riparian and wetland sites; and (4) present type-specific information on resource values and management opportunities.
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Other Works Cited
Adams. 1994.
Amman and Schmitz. 1989.
Amman et al. 1977.
Arno et al. 1993.
Arno et al. 1995.
Attiwell. 1994.
Ayres and Lombardero. 2000.
Baker. 1988.
Bartos et al. 1983.
Bendix. 1994.
Bevins. 1980.
Bilby. 1988.
Bradley. 1988.
Brookes, Stark, and Campbell. 1978. (In Stoszek 1988)
Brown. 1978. (In Graham et al. 1999)
Brown. 1983.
Calhoun. 1988.
Camp. 1996.
Campbell and Franklin. 1979.
Caraher et al. 1992.
Carleson and Wilson. 1985.
Catellino et al. 1979.
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Cochran. 1979.
Cochran et al. 1995.
Cole and McGregoor. 1988.
Cooper and Pfister. 1984.
Covington and Moore. 1992.
Covington et al. 1996.
Crowe and Clausnitzer. 1997.
Cushman. 1981.
Dahms. 1949.
Dale et al. 2000.
Dick. 1991.
Dong et al. 1998.
Elias. 1980.
Environmental Laboratory. 1987. Corp of Eng. Wetlands Delineation Manual.
Everett and Baumgartner. 1997.
Franklin. 1993.
Franklin et al. 1995.
Glinski. 1977.
Graham et al. 1995.
Grime. 1977.
Hadley. 1994.
Hall. 1988.
Hann et al. 1993.
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Harrod et al. 1997.
Harrod et al. 2000.
Harvey et al. 1993.
Harvey et al. 1994.
Helvey. 1980.
Hessburg and Everett. 1993.
Hessburg et al. 1993.
Heyerdahl. 1997.
Hughes and Edwards. 1978.
Hunter. 1991.
Heyerdahl and Agee. 1996.
Johnson and Clausnitzer. 1991.
Jurgensen et al. 1994.
Kaczynski. 1994.
Kauffman. 1988.
Kauffman et al. 1983.
Knopf. 1991.
Linhart. 1988.
Lynch and Swetnam. 1992.
Mahoney. 1977.
McCune. 1983.
Meffe and Carrol. 1997.
Meyer et al. 1992.
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Meyer et al. 1995.
Miller and Kean. 1960.
Mitchel. 1987.
Mitchell. 1990.
Moeur. 1992. (In Graham et al. 1995)
Monnig and Byler. 1992.
Morrison and Raphael. 1993.
Morse. 1999.
Mutch et al. 1993.
Naiman et al. 1992.
Naiman et al. 1998.
Nierenberg and Hibbs. 2000.
Nyland. 1996. (In Graham et al. 1995)
O’Laughlin. 1994.
Ohlson et al. 2001. (Unpublished research)
Olsen. 1981.
Olson and Knopf. 1986.
Payne et al. 1996.
Perry. 1995.
Peterson and Hibbs. 1989.
Raphael and Morrison. 1987.
Robinson. 1999.
Roche and Talbot. 1986.
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Rothermal. 1983. (In Graham et al. 1999)
Rust. 1990.
Schenk et al. 1980.
Schmidt and Fellin. 1973.
Sidle et al. 1985.
Skinner. 1997.
Steele. 1994.
Stoszek. 1988.
Stoszek. 1994.
Swanson. 1972.
Swanson. 1988.
Swanson et al. 1981.
Swanson et al. 1994.
Taylor. 1990.
Thompson and Shrimpton. 1983.
Tiedemann et al. 1979.
U. S. Department of Agriculture Forest Service. 1992.
Wheeler and Critchfield. 1985.
White. 1987.
Wickman. 1990.
Wickman. 1994.
Wischofske and Anderson. 1983.
Wondzell and Swanson. 1999.
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PART 3 APPENDICES
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Appendix
A
Professional Contacts List
CTC Project Team Contacts
The CTC project team attempted to contact the following individuals over the course of this project. Attempts to contact these individuals were not always successful. In some cases, highly relevant and current information was obtained.
Andy Youngblood, U.S. Department of Agriculture Forest Service Ann Camp, U.S. Department of Agriculture Forest Service Blake Rowe, Longview Fibre Brion Salter, U.S. Department of Agriculture Forest Service Bruce A. Keleman, Okanogan & Wenatchee National Forest Service Bruce Lippke, University of Washington Bud Kovalchik, U.S. Department of Agriculture Forest Service (retired) Candy Parr, Boise Cascade Carl Davis, U.S. Department of Agriculture Forest Service Carl Davis, Wenatchee National Forest Chad Oliver, Yale University Charlie Johnson, U.S. Department of Agriculture Forest Service Craig Schmitt, U.S. Department of Agriculture Forest Service Darlene Zabowskii, University of Washington David Sandberg, U.S. Department of Agriculture Forest Service Dennis Ferguson, U.S. Department of Agriculture Forest Service Diana Olson, U.S. Department of Agriculture Forest Service Domoni Glass, CMER SAGE Don Scott, U.S. Department of Agriculture Forest Service Duane Vaagen, Vaagen Brothers Lumber Incorporated
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Ed DePuit, U.S. Department of Agriculture Forest Service Fred Ebil, Society of American Foresters G. Elton Thomas, Okanogan & Wenatchee National Forests Gardner Johnston, University of Washington Geoff McNaughton, Washington State Department of Natural Resources Greg Filip, Oregon State University Jan Henderson, U.S. Department of Agriculture Forest Service Jeff Light, Plum Creek Timber Jerry Franklin, University of Washington Jim Agee, University of Washington John Bassman, Washington State University John Beebe, Tufts University John St. Pierre, Colville Tribe John Townsley, U.S. Department of Agriculture Forest Service Larry Irwin, National Council for Air and Stream Improvements, Incorporated Maurice Williams, CMER SAGE Mike Liquori, Campbell Group Paul Flanagan, U.S. Department of Agriculture Forest Service Paul Hessburg, U.S. Department of Agriculture Forest Service Penny Morgan, University of Idaho Richard Schellhaas, U.S. Department of Agriculture Forest Service Rod Clausnitzer, Okanogan Valley Office, Okanogan-Wenatchee National Forests Ron Neilson, Oregon State University Ronald P. Neilson, U.S. Department of Agriculture Forest Service Shari Miller, U.S. Department of Agriculture Forest Service Sondra Collins, Upper Columbia United Tribes Susan Bolton, University of Washington Terry Hardy, Boise National Forest Terry Lillybridge, U.S. Department of Agriculture Forest Service Tom Swetnam, Arizona Tree Laboratory Wallace Covington, Northern Arizona University Wayne Padgett, U.S. Department of Agriculture Forest Service
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Additional Contacts
In addition to the calls and emails made by the CTC project team, Domoni Glass, CMER SAGE Co-Chair, distributed an email requesting assistance on the project to members of the CMER SAGE mail group. Members of the mail group are listed below with affiliation, when known.
Ash Roorbach, Northwest Indian Fisheries Commission Blake Rowe, Longview Fibre Charles Chesney, Washington State Department of Natural Resources Charlie McKinney, Washington State Department of Natural Resources Cindy Confer, Washington State Department of Fish and Wildlife Dave Schuett-Hames, Northwest Indian Fisheries Commission Dennis Parent, Inland Empire Paper Company Doug Martin, Martin Consulting Dwight Opp, Stimson Lumber Eric Krausz, Colville Tribe [email protected] (name unknown) Heather Rowton, Washington Forest Protection Association Jean Parodi, Washington State Department of Ecology Jeff Grizzel, Washington State Department of Natural Resources Jeff Light, Plum Creek Timber Company Jim Matthews, Yakima Tribe Jim Preist, Colville Tribes Jim VanderPloeg, Boise Cascade Joe Maroney, Kalispell Tribe Joe Weeks, Washington State Department of Natural Resources Joni Sasich, Independent Contractor Ken Bevis, Washington State Department of Natural Resources Lynda Hofmann, Washington State Department of Natural Resources Maurice Williamson, Williamson Consulting and WFFA Mike Liquori, The Campbell Group Pete Peterson, Upper Columbia United Tribes
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Ron Simon, Longview Fibre Sondra Collins, Spokane Tribe Steve McConnell, Northwest Indian Fisheries Commission Steve Stinson, Washington State Department of Natural Resources T. Anderson, Kalispell Tribe Terry Jackson, Washington State Department of Fish and Wildlife Todd Baldwin, Kalispell Tribe Wade Pierce, Stimson Lumber
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Appendix B
Spokane Forest Dynamic Workshop Transcribed Text
Transcribed Text from the ERSAG Forest Dynamic Workshop, February 22, 2001
Transcribed text, in the form of four text files, for the February 22, 2001 workshop was provided to the CTC project team electronically in four files. The contents of those files are presented below. It was not possible to validate the contents of these files, so the CTC project team made minimal effort to correct possible errors.
Tape 1 Speaker: Domini Glass
00:00:00 00:00:55 Welcome to the workshop. I’m Domoni Glass and I’m an independent consultant working in the forestry business for a number of years now. Wanted to take a couple of minutes to refresh our memories and for those who haven’t been here to bring you up to speed on why we’re here.
As most of you probably know, we have or are about to have new Forest Practice Rules for the State of Washington. In the process of negotiating those rules, there were a number of items that came up, places of uncertainty which we didn’t have some answers for, and those were all put on a list of priority research items that the communities as a whole have agreed to go ahead and research so that we can get some answers, and put them into a sort of adaptive management loop. We want to find out first of all, are the new rules effective? And if they aren’t, what are the adjustments to make and like I say, they are some outstanding questions that we made our best guess on as we were putting together the rules that we’re going to want to get some additional information on. In order to address those questions there’s a group called CMER that is, has people from the forest industry, from the various regulatory agencies, tribal groups, not many environmental people there, but they are very welcome to be there, that has been charged with putting together study plans and getting these studies done. We’ve got funding, both federal and state money to try and get some of the work done. CMER has split up into a bunch of subcommittees and one of them is dealing RIPARIAN DISTURBANCE REGIMES IN EASTERN WASHINGTON Concurrent Technologies Corporation - 234 -
with riparian issues. Now the riparian issues that were listed included some questions about disturbance histories on Eastside riparian forests and some other uniquely Eastside questions and they decided to spin-off a subcommittee that’s dealing with the Eastside riparian situations and that group is largely represented here, is charged with trying to put together the study plans to answer some of those outstanding questions. Anyway, at this point I probably, one of our highest priorities is to try to get our arms around some of the Eastside disturbance regimes and we were realizing that in the literature, there’s not a lot of information on that. But we also realize that there’s a lot of good work going on right now out in National Forests, at the universities, a lot of places. And our group needed to come up to speed. To find out who’s doing what out there so that we don’t start duplicating effort and make sure that whatever we do measures well to what everybody else is up to. So with that I’d like to get started. The first presentation we have is with Dick Shellhouse and Don Spuback, from the Wenatchee Forestry Science Lab and the Wenatchee National Forest. And I know they’ve been working on some fire frequency and riparian area work and we’re going to hear about that. After they’ve done their presentation we’ll open up things to questions. We want to keep this fairly informal and give everybody an opportunity to pick brains and make sure we have a thorough understanding about what’s going on.
Speaker(s): Dick Shellhouse and Don Spuback
00:07:36
I’m going to kind of tell you what we’re about to show. Probably, the first three quarters of these slides are going to deal with landscape and historic fire regimes. Pretty much in the Ponderosa Pine/ Douglas-fir forest series. And we have a few slides at the end where we’re going to talk specifically about historic fire regimes in riparian areas. Both in Douglas- fir/Ponderosa Pine series and Red Fir series. When we talk about historic disturbance, we’re talking specifically about fire. And our definition of historic is a hundred years ago. Anything prior to 1900, we determine as historic.
Slide: Eastern WA Historic Fire Areas 00:08:41
Let me just interpret this for you then. For the last ten years, we’ve done a lot of historic fire regime projects in Eastern Washington. And all the way from the Colville area up there in the northeast corner, clear down to the southern part of the forest. We’ve sampled not only what we call Large Landscape Areas, that represent major planning units for the forest, they range in size from ten thousand to forty thousand acres. Those little red triangles you see are the areas we’ve sampled for our historic fire regimes and riparian zones. It covered the Okanogan National Forest and a lot of the Wenatchee. So we have a pretty good distribution of historic fire data in Eastern Washington.
Slide: Fire Disturbance Assessment 00:10:15
Some of the answers we wanted to try to get a handle on was what was the historic fire frequency? How severe were the historic fires? And how large were they?
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Slide: Photo of Tree/Forest 00:10:34
Before we went out to actually collect these cross-sections, of fire scars, we had to set up a what we call Master Chronology. It’s a procedure that’s used in dendrochronology so that we can cross-date tree rings to determine when fires occurred. So we go out and collect tree cores from what we call very sensitive trees, and their tree rings relate the weather patterns. If they’re real tight, it means it was a real dry year, real wide, it’s a wet year. They’re very sensitive to moisture conditions.
Slide: Core Tray 00:11:24
We bring those cores in and sand them down.
Slide: Skeleton Plot 00:11:30
Then we put together what’s called a skeleton plot. But what we do is take the core and we map the ring characteristics on a piece of graph paper. And you can see a real tight ring here (indicates to slide) 1721, we’ve mapped that on the graph paper, it’s a tight ring. These rings here are real wide, these were wet years.
Slide: 00:12:05
When we line up all the samples you can start to see patterns develop of wet and dry years.
Slide: Composite Skeleton Plot 00:12:22
There we’ve put a composite skeleton plot and we list the wet and dry years, go back to the 1600’s. We’re going to use these dates to determine when fires occurred.
Slide: Sample Collection 00:12:44
A lot of the materials we select to study the fire scars is from dead material. And the only way you can date those scars accurately is to use mapping such as this.
Specimen: 00:13:00
Here’s an example of one. This is off an old stump. Now there’s no way you can date that unless you could cross-date it. Even with material that you have the cambium date , there’s many times it’s missing rings and it’s just to verify that, you need to be able to cross-date.
Slide: Cat Face 00:13:27
Once we have our master chronology developed, then we go out and we look for samples. And the samples are usually found on the ponderosa pine, on uphill sided trees. This is what’s called a cat face. Once a tree is scarred, in its early development, that then sets the stage for it to scar again. Consecutive secondary fires. The protective bark is now missing,
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this allows it to scar much more easily. So we get repeated multiple scars, this gives a very good record of the past history.
Slide: Fire Scars 00:14:19
All those vertical lines is an actual fire.
Slide: Old Snag 00:14:29
We take samples from old snags. You can see there (indicates to slide) we just took what we call a bore cut. Which is we just take a piece out.
Audience: And you were real successful in getting that back to the right year sequence?
Speaker: Yes
Slide: 00:14:59
Especially in the pine zone where the sensitive trees we talked about, we can make a good map of fire years. We’re very successful with those. Somewhat less in moister areas. This is, you guys ever hear of the Tyee Fire? 1994, a lot of acres burned. This is within the Tyee Fire area. And we actually took cross-sections from forest fire trees.
Slide: Oak Snag 00:15:43
We took a sample from that oak snag there.
Slide: Snag Sample 00:15:51
That’s a sample from that snag. You can see that the majority of that is decomposed. There’s no ring pattern out here (indicates to slide). This is all we have to work with. These little dark lines are from when the fires occurred. Those are fires scars. The other way we could date that is to cross-date.
Slide: Logged Stump 00:16:21
Take samples off of previously logged stumps.
Slide: Stump 00:16:30
Sometimes we just take a section out of a stump.
Slide: 00:16:36 Slide: 00:16:41
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In that particular that previous slide there (referring to Slide 00:16:36), what is showed was that the scar itself can help preserve the wood that most of that was decomposed but the scar itself was still intact. And we find that quite often.
Slide: 00:17:05 (reversed to previous slide)
Especially in ponderosa pine, the resin helps preserve.
Slide: Bore Cut 00:17:14
On live trees we take a sample out like this. It’s called a bore cut. The sample we take historic fire level of the cambium.
Slide: 00:17:45
That’s after it’s cut.
Slide: 00:17:50
There’s a sample.
Slide: 00:17:56
Here’s a sample from a Western Ars tree.
Slide: 00:18:03 Slide: 00:18:08
Here’s a sample from an old snag. I’m waiting for somebody to say ‘is that gonna fall?’ (laughter) on Don...where’s his hard hat? (laughter)
Slide: 00:18:32
Then we bring them in and we store them and dry them.
Slide: Sample Preparation & Analysis 00:18:40 Slide: Sample Sanding 00:18:44
All the samples are sanded.
Slide: Reading of Sample 00:18:51
Then they’re read. Now we’re in the process to try to date each individual fire year.
Slide: Man bent over sample to read 00:19:01
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How’s your back? (laughter)
Slide: 00:19:11
This shows the importance of the cross dating that we’ve set up originally. (Indicates to slide) XXXXXX of cross dating here, there’s a real narrow one there, 1739. See the real skinny one there in 1721. That rake pattern helps put us in the ball park of when to date the fire scar years. It is important to find what we call a Signature Year or a Marker Year, prior to the fire. Following the fire many times the tree has undergone such trauma, that there, it may not put on a ring. All around the tree, just in certain conditions.
Audience: How can you know with certainty that you’ve had a light ground fire, or is that getting a little too iffy?
Speaker: Well, there’s some assumptions we can make. The years following the fire, we can look at the ring patterns. And on some samples, the ring patterns it looks like they’ve been released, they’re growing really well and on following some fires, it looks like they’re really suppressed, like it was a hot fire, maybe it burned the crown.
Audience: Can you relate those things to the potential quantity or whatever of the like XXXXXXX being killed?
Speaker: No
Slide: Growth Patterns Resulting from Fire 00:20:56
Here’s a slide showing what you were just asking about. You can see on following some of those fire years, (indicating to slide) see right after that fire see how the tree released? An assumption could be that that fire killed some of the competition. There’s a little thinning going on. That one up there (indicates to slide) following that fire, the tree was suppressed. So that would suggest maybe the fire got into the crown. This is little hotter.
Slide: Fire Scar Characteristics 00:21:41
This is some of the characteristics that help us identify the scars. You have that the curvilinear healing process, there’s char. There’s always scars obviously, so we need to determine if it’s a fire scar or not. The main thing we look for is the char.
Slide: Watch Out!! 00:22:12
This is another example of using the cross-dating procedures to look for what’s called missing rings and sometimes false rings. When trees undergo a lot of stress, sometimes they don’t put on a continuous annual ring. As you can see that narrow ring there (indicates to slide), see how it fades away on the right? And if there’s many of those on a sample, and if you were just counting rings, you’re going to be off many years. The consequences of being
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off even two years, is it adds that another fire to the chronology, the fire chronology and it would make your composite inaccurate.
Slide: 00:23:09
Now that the samples have been dated, you can see there’s some really significant characteristics showing up. If you look at the center of the tree, when that tree germinated in 1811, and now look at the size of that tree when it was first scarred. Very small. Followed by repeated fires until 1925. And then that disturbance pattern was shut off.
Slide: Old Stump 00:23:51
Here’s a sample of an old stump
Slide: 00:23:59
There’s a dated bore-cut section. And again, it’s the same characteristics showing up on the majority of these samples. We look when a tree germinated, we look when it was first scarred. It’s an indication that that’s a low severe fire, it was a very small tree. We also look at the turn of the century, after the 1890’s, that’s another disturbance.
Slide: 00:24:32
Sometimes we don’t have much to work with. This was just the outer shell of an old stump. But again, with the dendrochronology procedures for cross-dating, we can date those fire years.
Slide: Fire Extent 00:24:53 Slide: Entiat Fire Scars 00:24:58
What about how big were the fires historically? Well, this particular landscape unit is about 40,000 acres. This was on the Mud Creek area in the Wenatchee. That light, what color is that, chartreuse, green, …this is the boundary of our study area. Now within this study area, (indicates to slide) we have these little blue lines which stratify the study area by what we call Land Types. And Land Types, we based on percent, slope and aspect. We separated north to south slopes. We separated tallow terrain from steep terrain. The theory was that fire behavior might have been different based on aspective slope. But as you look at the fire extent, it XXXX that fire didn’t recognize these land types. Fires burn across ridge tops. They burn across riparian zones. These were big fires. 1791, you know, that’s a 30,000 acre fire. Again, this is in the dry forest.
Audience: Could you tell differences in the fire (inaudible)…might be able to extrapolate (inaudible) were you able to pick up on differences (inaudible)
Speaker: Not particularly. When we did talk about that in general, but not specific to fires.
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Slide: ’86 Burn Area 00:27:18
This is the same study area. In 1886 the riparian area burnt. And again if you look at the land type boundaries, historically fire didn’t recognize those land types. The little red splotches in there are where the fire scar samples came from.
Slide: Fire Size by Year Entiat/Mud Creek Area 00:27:50
Here’s a pattern of historically how big fires used to be. Until you get to about 1900, then there’s a dramatic drop-off in fire size. Until you get to 1994, that was the Tyee Fire. Now the acreage of the Tyee fire was about the same size in this area, but the difference is the Tyee Fire was more severe. It was standard replacement. And if you look at the frequency of fires along this fire suppression period, it was just about as frequent. They put them out though.
Slide: Fire Size by Year Nile Planning Area 00:28:48
This is a smaller planning unit on the southern end of the Wenatchee Forest. It’s about 8,000 acres in size. It’s also in the Pisby/Pipo Series. Same pattern. Historically fires were fairly large. Until 1900.
Slide: Fire Frequency 00:29:18 Slide: Graph 00:29:21
Well, how often did these fires burn? We put all our data into an FHX2 Database and developed what’s called a Composite Fire Chronology. On the right hand side there are the individual fire scars. And along this x-axis down here (indicates to slide) are the years those sample recorded a fire. We use a composite because it tells a more complete story. If you use a single tree, it may not record every fire.
Slide: Fire-Free Intervals Prior to 1900 00:30:15
So the fire-free intervals for both the Entiat 40,000 acre area and the Nile 8,000 acre area, were about the same. The red and blue bars there just signal there’s difference between the land aspects. Those are north and south slopes. There was no significant difference. On the average, the Entiat burns every seven years. And the Nile is about every eight years.
Slide: Percent of Polygon Burned per Fire 00:30:56
The other thing we were interested in, is when there was a fire, how big was it within that polygon? Fire-free interval tells you one thing: it tells you there was a fire somewhere out there in the landscape every so often. But it doesn’t tell you how much it burned. This tells you what percent of each polygon burned when there was a fire. And you can see that when there was a fire within these polygons, it was burning 58 percent on average on the Entiat and over 50 percent on the Nile. So this a very clear the fires were large.
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Audience: What is the Nile (inaudible)?
Speaker: The Wenatchee’s district, mostly Yakima.
Slide: Fire Intensity 00:31:50
So we know how often fires burned, we know how big they were, but how severe were they? What was the fire intensity?
Slide: Fire 00:32:12
Historically, fires were basically ground fires. They were burning grass, pine needles.
Slide: Cross Section 00:32:25
Some of the samples we collected show the same pattern. That historic fires were very low, low severity. If you look at that first fire scar (indicates to slide) 1741, that tree’s a half inch in diameter.
Slide: Sample 00:32:50
There’s another one. And the interesting thing on that, if you look on that tree, it was first scarred, look at the percentage on that tree where the cambium was killed. Over 50 percent of it, and it still survived.
Slide: Sample 00:33:12
Here’s a sample that’s a little over a foot long, has multiple scars on it.
Slide: Sample 00:33:21
There’s a cross-section, not quite a foot, has many fires on it. So even on a tree, that remains a small diameter tree, it still survived multiple fires.
Slide: Average Diameter at First Fire-Scar 00:33:43
Average diameter of trees when they survived their first fire, they were about three inches. And keep in mind this diameter is at stump height. So the deviate’s diameter would be much smaller. And again, there wasn’t much difference between north and south aspects.
Slide: 00:34:16
This here is a photo taken in western Montana, some of you have probably seen this series. This was a Ponderosa Pine/Douglas-fir habitat type. And that’s really supposed to be 1908 (picture indicates 1909) but pay attention to the understory, from the forest floor in 1909.
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Slide: 00:34:49
That’s the same spot, twenty years later, and you can see what’s coming in. Shade tolerant, climax Douglas-fir.
Slide: 00:35:03
And forty years later, you now have what’s called fuels, that’s a setup for a standard replacement fire. That’s what a majority of our dry forests look like today.
Slide: 00:35:24
You can see that our old seral pine are being snuffed out, being choked out. We’re gonna lose our old growth pine legacy.
Slide: 00:35:45
You can see the dove tops on the old pine growth back there. There’s too much competition and a fire gets in that stand, they’re all gone.
Slide: 00:36:03
They also have an insect problem. That’s a spruce budworm breakout in the southern part of the forest.
Slide: 00:36:20
And this is what we faced. That’s what we had in 1994.
Slide: 00:36:28
That’s what we’re left with.
Audience: That’s the Tyee right there, isn’t it?
Speaker: Yes, it is.
Audience: I scheduled to try riparian sampling the summer after that happened, but I gave up after two days, everything went. I found two plots that weren’t burned, two pieces in the riparian zone that weren’t burned, at least where I looked. Did you do any sampling down in riparian zones with that opportunity?
Speaker: We did.
Slide: Conclusion 00:37:07
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Here’s our conclusions when we think about historic fire regimes and the dry forest. Current stand structure and species composition are not in synch with historic disturbance regimes. Historically, fires were frequent and of low intensity. Currently, fires are infrequent and of high intensity. Historically, fires crossed land types, ridgetops and riparian areas. Results of this scientific research has let do the implementation of the Wenatchee National Forest’s “Dry Forest Strategy.” Both the Wenatchee and the Okanogan are in the process of thinning a lot of acres of the dry forest.
Audience: The statement, two statements: fires were frequent of low intensity, now they’re infrequent of high intensity, there was a slide, several slides ago, showing the frequency and it didn’t look like there was a whole lot of difference, which confused me when I saw it. Was I just misinterpreting it?
Speaker: (inaudible)
Audience: The frequency slide that was addressing the frequency, it seemed to have the same number of bars as for recent history as for older history.
Audience: What was the last year on that slide?
Audience: I think Don said that they were suppressed or put out.
Speaker: That was fire size? No, that was frequency, which the statement, currently, (inaudible)they’re infrequent, meaning they’re infrequent, allowed to become natural fires. The frequency was still there, but we put them out when they were small. We counted them XXXXX for the records, from the records.
So if you pick a spot on the landscape the frequency has gone down.
Audience: The other thing that’s to me a little bit, I’m confused I guess, I had assumed, that the frequency probably would have been greater prior to, effectively when the Native Americans were given small pox, and mumps and everything else. It would appear there was be a big change in the frequency like after 1878. It appeared that it was more or less the same since.
Speaker: In this particular area, where we had done this work we didn’t see a lot of difference in it. Now there’s some work that we’ve done, I think up in Colville, where we did see some of that.
Audience: How often did you get off into the non-dry site strategy areas? In other words the (inaudible) areas, where historically in my opinion, you dealt with infrequent standard replacement fires more often than the other areas. Did you do much studying there?
Speaker: Well, we have. We’ll talk about that. We’ve done, we go into what you call the Grand Fir Forest Type with water is that what you’re talking about?
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Audience: Well, it’s intermediate.
Speaker: Also, even within the Dry Forest Type, on the north slopes, we have shown that on the north slopes, there was occasionally standard replacement fires, on the north slopes, small, because of the fuel buildup. Now keep in mind, say you have an average fire interval of seven years, that’s all it is, it’s an average. You also have a range. In this area the range is from one to sixteen years. So if you have a sixteen year maximum interval, and you’re on the north slope, you’ve got time for fuel buildup.
Slide: Evaluation of Historical Fire Disturbance in Riparian Zones 00:41:32
Okay, now to talk about riparian zones. These slides didn’t turn out very good. We made these kind of (inaudible, laughter) so, just act like they’re good. This is we are working on a paper right now. The paper is going to be called “The Continuity of Fire Disturbance Regimes Between Riparian and Adjacent Site Slopes.” So the results I’m going to show you is, this work is still in progress.
Slide: Valley Types 00:42:27
They had to define, it was really confusing, because each different agency seems like has a different definition for a stream type. Forest Service has one, the State has one, so how are we going to find what we’re talking about here. So we decided on using what we call these Valley Types. That was described by Cupp. There’s a brief definition of say an E-1 Valley Type, it’s just a V-shaped, moderate, channel gradient. And then you go clear down to say an F-1, which is a U-shaped trough. (inaudible) We want, we sampled 26 different stream sections within the Okanogan and Wenatchee National Forests. We sampled upper, middle and lower parts of the streams. A lot of our data, the results of our data, are based on fire scar results are from both the sideslopes and the intermediary parts of them. And a lot of the data in the riparian zone is what we call Stan Cookwert Data. There was less fire scar samples in the riparian zones. So we had to rely heavily on Stan Cookwert data. You’ve got these all memorized, right? (laughter)
Slide: 00:44:13
This is again in the dry pine, Douglas-fir Series, those little yellow circles are where we collected fire scar samples. And in the upper left hand corner there, (indicates to slide) you can see what we call an E-3 valley type. In the little channels going up to the right and left, these are what we call E-1, E-2. They’re just narrow troughs. If you want to put those in Rosgen terminology, you’ve got A’s out in the valleys and probably a B down in that main valley.
Slide: 00:45:11
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This is Swauk Creek in the Wenatchee. It’s a pretty wide valley bottom and right in the bottom of it, we have, there are scarred stumps.
Slide: 00:45:33
That’s actually a fire-scarred stump on the left right by the creek.
Slide: 00:45:43
There’s a sample taken from the creek bottom.
Slide: 00:45:53
The Swauk Creek area is in the Grand Fir Series, it’s a little later. All those little black dots are where we collected fire-scar samples. And (aside: “show them the Swauk Creek Area”, speaker indicates to slide) that’s the Swauk Creek Corridor. (aside: “go up to that 16”) There’s a little cluster of fire scars that we collected right in the creek bottom, right in Swauk Creek. And that’s called a plank sample. That plank sample reveals that fires burnt there every sixteen years. Now if you go on the other side of the slope, which would be the south slope, there’s another plank sample, that’s up on the sideslope, and that burned every fifteen years. And if you come across on the north slope, it’s got an eighteen year frequency. And if you come clear back down the Swauk Corridor, we’re still in the main Swauk drainage, and where’s that cluster on the bottom, right there, that plank burnt every fourteen years. We actually have a total for the whole Swauk LSR, we’ve got like 700 fire scar samples out of there.
Audience: What’s the elevation of this, Swauk Creek?
Speaker: Oh, I’d say 3500 feet.
Audience: That’s where Highway 97 coming?
Speaker: Yes, cause the top of Swauk Pass is 4000 feet.
Audience: The important thing here is that you’re not in some arid climate, you’re way out on the edge and I’d argue it’s changing the continental climate. It’s not an area that looks like a hemlock or a fir zone where as XXXXX would say XXXX long intervals between standard replacement fires. The valley bottoms may tend to go like the other ones, same patterns.
Slide: ABGR Series, Tree Age and Fire History 00:48:21
This is a histogram of the same area. This was actually taken from the Spotted Owl nest site up there. The Swauk Creek area at LSR has a lot of Spotted Owls. And we were doing fire history on Spotted Owl nestings. It’s the same pattern. If you go back, the little flames represent when fires occurred within that stand, and again, this is a Grand Fir series. Up until
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about 90 years ago, fires stopped and the stand structure totally changed. We now have an influx of mass numbers of Grand Fir.
Audience: So as far as trees per acre, looking at age class? 210
Speaker: Yes, that’s age class.
Audience: .. so you’re saying there were very few trees per acre during that time
Speaker: Yes
Slide: Percent of Total Disturbances 00:49:38
Now here’s my good slides. (laughter) Okay, so we’ve gone into these valley types, we’ve sampled upper, middle and lower sections of these valley types, we’ve got the sample from both sideslopes, and then the bottom, so, what’s the percent of disturbance that was showing up in the riparian zones? That’s what this is showing. (aside: “put it on E-1 there”) Example, an E-1 valley type. Thirty-five percent of the fires have shown up within that those sideslopes and that drain ditch. Forty-five percent were in the bottom.
Audience: Forty-five percent of the total fires?
Speaker: Yes, of the total fires. We’ve even stratified it further by aspect, we’ve got north, south, east, west slopes in the middle there. We’ve stratified it, on the right hand side here, by plant association groups. And overall, you can draw a straight line at about forty-five percent.
Audience: When you’re forming these graphs are you basing it on whether a natural or a anthropogenic-caused fire? Or did you distinguish that in your studies?
Speaker: No. The previous XXXXX we think that there’s a strong influence in the Swauk Creek area. Many of the fires were found just near the in and near the bottom, didn’t spread very far at all. And there’s documentation that the natives, the Native Americans were encamped in that area.
Audience: Did you do any sampling across the Pass and into the next range? I’m thinking of those upper miles of wet Spruce, miniature Dogwoods, forests. My impression there is those Spruce are pretty old and that’s a low fire frequency regime, well into the Douglas-fir, Grand Fir, Ponderosa Pine XXXXX?
Speaker: Okay, there was no Spruce here.
Audience: Yeah I know.
Speaker: We didn’t sample any.
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Audience: The grange are in that Grand Fir Vanilla Leaf goes virtually to the Pass.
Speaker: Yeah, and a lot of this data is from the Okanogan (inaudible).
Speaker: Hey, we’ve got to back up. Sorry. This table here is showing you results of the Ponderosa Pine/Douglas-fir Series.
Audience: (inaudible)
Speaker: Yes, and the sideslopes.
Audience: Still the Swauk Creek Area?
Speaker: Yes
Audience: And this is from the Okanogan I just heard you say?
Speaker: Okanogan and Wenatchee.
Audience: Very dry climate.
Speaker: This represents, yes, 26 different stream channels.
Slide: Similarity PIPO/PSME Series Riparian vs. Sideslopes 00:53:21
Percent similarity within the dry series. In other words, help me out Don, percent similarity: of those fires that occurred in the riparian zone, how common were those fires on the sideslopes? Same fire years? Okay. And again, we’ll use E-1. E-1, 38 percent of the fires were common between a riparian site and sideslopes. I guess the point being, it seemed like it would be a good idea, to look at sideslopes and the riparian as a whole, cause they are, there is some continuity there.
Audience: So you are saying though that the sideslopes burned more often?
Speaker: Yes. Yes. And many times when those, the similarity with a fire in the bottom was in relation to the XXXX sideslope. Sometimes it was the sideslope, sometimes it was both.
Audience: Do you mind me jumping in?
Speaker: No. No way.
Audience: You’ll get all this when I give the next talk, but number two, within the cross- section, across the valley, you get a lot of variation. Usually, part of that is XXXX. If you’ve got different series, such as the Alder, the Willow, or the Subseries, then you know you’re dealing with different fire regimes. So we’re talking about forests
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that plant associations, or habitat types, that we’re talking about, I presume. In the case of the Tyee fire, places that you didn’t expect would burn, still burned. That thing just took everything.
Audience: Exactly what are we talking about in terms of distance. I guess I mean horizontal distance, where you defined sideslope versus riparian area?
Speaker: We used the same definitions that was in the Forest Guidelines. Based on their definition of streams, they have what they call Stream Class, One through Four. And based on what class it is they have a buffer zone assigned to that as what is the riparian zone. 150 feet, 300 feet, whatever the class a stream was.
Audience: From the stream bank or from the edge of the valley?
Speaker: That’s from the stream bank.
Audience: You’re talking to people who are dealing with State Regulations, which are not very liberal, at this point at least. We’re talking something under 120 feet, on one side of the stream, mostly, in this terminology. So, is there any way you can tell us, basically that’s for all classes of streams, basically it is. So can you tell us how those numbers would relate to that? Do you have any idea how those numbers would relate to those buffer widths?
Speaker: I do, but I don’t have it with me. I can make some assumptions. Again, we, in the stratification process, we went away from extreme class classification, to valley types. And we know what class extremes those valley types were, and we know about the riparian buffer widths were. For example, I’ll just give you some examples, and E-2 and an E-3 valley type probably has a 100 foot buffer. The F-1, the E-3 and F-1 have a 300 foot buffer. These are measures, almost reverse.
Audience: But you see, a proportion of that buffer, how much of it burned, I guess my question is, is that a significant source of variation or not? I guess for something that you counted as occurring in the riparian area, may have been only a small part of the outer part of it, others virtually the whole riparian bottom. I mean how much of a source of variation is that?
Speaker: Where the samples came from? We stayed, I don’t know what the percentage is, but we stayed within that buffer zone, with the intent of staying right in the bottom.
Audience: Would it be fair (inaudible) E-2 if we had a for example a fire in the (inaudible) ten years on the south sideslope, would that be like 25 years within the riparian area? Is that what that 38 percent is indicative of?
Speaker: 38 percent speaks just specifically of those fires that were shared with the sideslope. In other words, 38 percent of the fires that were also found in the
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sideslope, were found in the bottom. You’re wanting to go back to frequency though, right?
Audience: Yeah, just to try to visualize it. My simple view would be then that the 33 percent, for 33 percent that would mean that for the interval where like ten years on the sideslope tend to be thirty years on the riparian.
Speaker: That would be (inaudible)….yeah. So again we’re back to Swauk Creek and we’re talking about some aboriginal influence.
Audience: So do you talk about that in your paper?
Speaker: I don’t believe so, no.
Slide: % Similarity ABGR Series, Riparian vs. Sideslopes 01:00:16
In the Swauk Creek grange, the percent similarity was 40%. The bottom there, fire frequency in the riparian zones, ranged from about eleven to sixteen years. Actually this isn’t part of the paper, this is something we threw together for here. In fact you can see the upslopes have a longer range, the higher range of frequency than the riparian. It would lead us to believe that there was some Native American activities going on above.
Audience: It kind of raises a question in my mind about that activity, could there be differences? Would the upslope fires move into the bottoms? Are we seeing a little bit of an artificial situation on the bottoms? See what I mean?
Speaker: Yeah, I do. We’ve got a map that’s gonna show some fire patterns here. I think most of this particular area from what appeared to be the opposite effect. It went from the lower upslope up.
Audience: Which is what made me think that the Native Americans had a lot of influence on these fires on the bottom. So diversely, how many of the fires that started on the ridges would have gotten into the bottoms? That’s what’s going through my head now.
Speaker: Yeah…a long time…(inaudible)
Audience: (inaudible) Actually, I think they’ve been there since some of the species (inaudible) So to say what was the effect of Native Americans, you wouldn’t know because you have an entirely different set of trees and findings. I’m just throwing out an idea, a problem.
Slide: % Similarity Opposing Sideslopes 01:02:18
We also measured percent of fires occurring on adjacent sideslopes. So you’ve got the valley type between them. But we have no data from those valley types. In other words, we’ve got
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an E-1 stream, or an F-1 stream, we don’t have any fire data from that. But both opposing slopes, on either side of that stream, was burning, like on the E-1, at 38%. Same fires. Same fire years. You look at when you get out of the PIPO/Pismay, the units, after, you see the percentage drop. The similarity. These numbers are from some of our landscape work that we just prepared for today.
Slide: 01:03:27
This is the Swauk Creek Corridor here again. I know it’s kind of hard to see, I think this is a series of four years. 1886, I believe is here. It’s hard to see but if you can see the red dots (indicates to slide) those are fire scar samples that show that particular fire. I can kind of draw the outline here. But you can see, a lot of it seemed to have retarded the spread of it by the corridor itself. A few places here, a small spot here, here it crossed over and here it crossed over. So in many cases the riparian areas act as a retardant to the spread. In many cases also, it did burn into our riparian areas, but didn’t cross the opposing sideslope.
Audience: So when you hit mountain alder, willow or something like that, that acted as a firebreak?
Speaker: Yes Occasionally it would go across. I just kind of looked at the numbers roughly, maybe 25% of the time it looked like it actually crossed over. There’s another one up here where it’s similar (indicates to slide) . That’s about three years later. And you can kind of see where the this fire here, three years earlier, had burned. Except this fire here was stopped at the stream bottom, but also at the boundary of the previous fire. So, fire also acts as a buffer. Here’s one of the areas (indicates to slide) where we thought there was some Native American activity. There’s many of these, just small spot fires around.
Slide: 1671 Fire 01:05:44
This is another one. 1671 it burned 14, 000 acres. Again this is the Grand Fir Series. You can see that that fire is highly variable. In some places it crossed the creek, in some places it didn’t.
Audience: These fires were just very low (inaudible) I’ve seen in other places, where you have such creeping fires (inaudible) so these weren’t something that would be a big event. I’m wondering could it be that these, instead of being, starting from one place, actually started from several places (inaudible)?
Speaker: Yes, that’s highly possible. Probable.
Audience: So I wonder if some of the places where they crossed, was it because Native Americans were on the other side of the river?
Speaker: Well the other possibility that you have too, if you’ve ever watched a, followed a lightning storm, come across Swauk Pass, man it just peppers different places on
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those ridgetops. In Swauk in particular, we don’t really, we do have some samples those few samples in box, we know it burned in box , but in these other areas, we don’t know to what extent it burned (inaudible).
Audience: Do you have, did you find any of the snags where it would just burn up the top of a snag, and then be in a position where it would just go in reverse?
Speaker: We don’t know.
Audience: Do you have any feeling for how intense this fire in particular was? Was it a mosaic, XXXXX? Were some of these actually XXXX snags, standard replacement fires or was it primarily all ground fire?
Speaker: I would say it was of mixed severity in places, particularly on the north slopes.
Audience: Small patches, on the north slopes.
Speaker: These north slopes tend to be fairly dry too.
Slide: Current/Historic Nest Site Comparison 01:08:16
Okay, we’re still on the Grand Fir Series. And we’re gonna talk about what was the historic stands compared to current stands. Now this is on sideslopes. This is not on riparian. Historically, some of those stands had 110 trees to the acre. And a hundred years later, they have 370 to the acres.
Slide: Current/ Historic Nest Site Comparison 01:08:46
This particular stand historically had 160 trees to the acre, and currently is over 900. The forest structure has been dramatically altered the last one hundred years. Not unlike the species composition.
Audience: I don’t suppose you could tell how many owls (inaudible)?
Speaker: I can’t. But what I can say is that the habitat they’re using is dramatically different today.
Audience: Do the XXXX sites ever show exactly the same thing? Where (inaudible) in other words, do they also show the 980 trees per acre?
Speaker: Which sites?
Audience: On all, on the unharvested sites? In other words, in my mind, (inaudible) are we talking (inaudible) harvested or regeneration (inaudible).
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Speaker: We’re talking a little of both, a combination. Most of these areas, from this, is from some overstore remove.
Audience: What are the, well in 1892, for example do you have any indication of what the size class distribution was? In other words, how many of those were ten inches and larger versus?
Speaker: Well we do from our data. We record every tree on the plot. And we can take every tree back in time to 1892. That’s how big it was. We also scale by the way. We also have some historical documentation by a fellow by the name of Plummer. Who did a forest inventory through this area around 1905 and he describes these hill sites as vast stands of Ponderosa Pine in the 20 to 24 inch size class.
Audience: What I’m getting at is does that 160 trees per acre, I have trouble envisioning 160 24 inch (inaudible)
Speaker: What you see here, there’s a variety of sizes class.
Audience: Okay. Okay, so it looks like there you’ve got two dolmans and co-dolmans
Speaker: Yes. Also, the fire interval for this Grand Fir Series in the Swauk area was kind of fourteen to twenty years. Again, that’s an average. There’s also a maximum. You can have a maximum of thirty years maybe. So, if you were, these stands were mapped based on at the end of the maximum fire-free interval. In other words (inaudible).
Slide: Percent of Historical Stand Density 01:12:06
We’re back in the dry forest again. We tried to determine in the riparian zone versus the sideslopes, which percentage, what was the percentage of quote old trees? Where did they exist? Well most of the old trees in the bottoms or beyond the sideslopes. And again, we’re using old, historic as a hundred years. What we found was overall about 30, 35 percent of the old trees were showing up in the riparian zone. There were more older trees on the sideslopes than there were in riparian zones. Okay, now that suggests several things. Why were there less old trees in riparian zone? It goes back to fire severity. If fires went through there, they were more standard replacement types. We also found fewer Culverts in the riparian zone than we did in the sideslopes
Audience: Culverts?
Speaker: Age classes of trees. Following a disturbance. It’s another indication, they’re a little more severe at the bottoms. So, we have these three things that we found. Fewer old trees on the bottom, we found fewer culverts in the bottom, and we found fewer bigger trees in the bottom.
Audience: Fewer snags at the bottom?
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Speaker: Yes.
Audience: Did any of that suggest what the species composition was there?
Audience: In that zone, correct me if I’m wrong, (inaudible) present conditions, Douglas-fir, Ponderosa Pine and Grand Fir were the primary species, and all three with some variation, as they get older at least are all pretty fire resistant, moderate to very, so those are the trees that were dominant and there would be more of a tendency for Ponderosa Pine to survive than Douglas-fir or grand fir.
Speaker: I guess the only thing I thought of was that you have a frequency of low intensity fires but you also have more of perhaps a frequency of more severe events and we think that the frequency, however long it was, even if it was longer, would be frequent enough to prevent the establishment and persistence of the old cohorts.
Audience: Yeah, and you’re dealing with a site one, site two very productive sites in the grand fir types, well all of them, down that mountain, if you get a long enough interval, you know just a couple of decades, you can build a lot of understory under there and then the next time through, get a standard replacement fire.
Speaker: Yeah.
Audience: (Inaudible) understory (inaudible) back at that kind of fire regime.
Speaker: And another variable is weather patterns. If you have a five year drought preceding.
Audience: So even in this disturbance, in this rotation, the dominant species was firs and conifers.
Audience: Just depends. I’ll talk more about that later on, answer that question I think. And if I don’t answer it…or you guys can talk about if you want.
Speaker: The dominant species in the bottom Tim?
Audience: Well, yeah, I’m just looking for an idea some sort of composition, what percentage of species, maybe, what you had there, what you were looking at?
Speaker: Yeah, we were looking at just conifers.
Audience: But on the terraces, that was Douglas-fir, grand fir and ponderosa pine.
Speaker: Historically, on the sideslopes, the stands consisted of 85% ponderosa pine, 15% Douglas-fir.
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Audience: The grand fir would grow further up on the north slope, but not too far up.
Audience: Am I hearing then that you could find maybe other species, say like maples, cottonwoods…
Audience: Oh there are a lot of cottonwoods in there. Different pluvial surfaces (inaudible) and some mix of (inaudible) but then (inaudible) terraces were primarily conifers. Vine maple, not vine maple, vanilla leaf, is a characteristic species underneath (inaudible).
Slide: Conclusions 01:18:20
Continuity in disturbance between riparian and sideslope forest and the continuity in disturbance between opposing slope forests suggest that management should consider landscape units in their entirety rather than rather than as riparian and sideslope isolates when implementing ecosystem and disturbance management.
Audience: Does that mean that the Forest Service is going to start doing that?
Speaker: (Laughter) You decide. The Forest Service will do whatever is the simplest.
Audience: The finding of those smaller trees (inaudible) fewer scars, in the bottom (inaudible) is similar to a study done in Mexico on Indian pines where they had hills and valleys, much (inaudible) gullies, and it’s what you were suggesting, that the hills were so poor in growth that you wouldn’t get much fuel buildup, at the same time, you’ve got a lot of fuel buildup down in the gullies, so when a fire came through, it would creep along the hills, and just wipe out everything in the gullies and you’d end up with then multiple (inaudible) scars, and big trees on the sideslopes, (inaudible)
Speaker: That’s just what we found.
Speaker: Another thing to consider in (inaudible) in those gullies, is the topography itself. You that could act as a (inaudible).
Audience: You could relate that tree count (inaudible)
Speaker: Yes.
Audience: Could you briefly explain the dry fire strategy and does it preclude to (inaudible)
Speaker: Dry fire strategy is a plan to try to put these overstocked stands in the dry forests back into a more sustainable state. And they’re trying to do that by thinning. Both commercial and Swauk Creek XXXX. Actually harvest activities. I don’t believe there would be much emphasis on old growth. Yeah, it would be thinning from below.
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Audience: But they can agree to use fire?
Speaker: Yes. Once the fuels are cleaned up.
Audience: In the drier areas?
Speaker: Yes.
Audience: Can you give us a quick snapshot on what you’re continuing to do, I mean what’s happened this year, next year?
Speaker: Okay, as I say, this paper’s still in progress. We are currently working on a paper where we describe, it’s called stand reconstruction. We take current stands back in time a hundred years to determine what the structure and species composition was. We’re also working on completing some fire history results up in Colville area. We’re working on, we’re gonna do, we’re gonna be working in cooperation with the University of Washington, on a climate regional Eastside fire regime for the State of Washington. We’re also working on, we’re comparing historic fire regimes and stand structures of our forests, to forests of Russia. Now the neat thing about Russian forests are, they’re still intact. They’ve never suppressed fires, in some of these areas. So we’re gonna make a comparison of those two.
Audience: Similar stand types?
Speaker: Yes. Yes. (inaudible) Snag. Prehistoric snags. We’re working on determining, we’ve already collected the data, to try to determine what historic snag levels were.
Audience: In the Russian comparison, do they have a good set of data where they’ve harvested and had frequent fire intervals?
Speaker: There’s no harvesting. No harvesting.
Audience: So there’s no (inaudible) harvest data (inaudible)
Speaker: Yes. Yes.
Audience: Also, if you could just rattle off real quickly, do you guys have study plans or anything like that, I’m kinda thinking forward for us, if we decide some of this stuff sounds like things that we need to know or if it will answer our questions. I’m just looking for sources of additional information so that I can. Snags is on our list…okay? If your study does solve our snag problem, could we get more detail to find that out, or do we have to do something?
Speaker: We’ve already produced one paper on snag longevity following fire. And again, the one we’re working on now is to determine what the historic snag levels were.
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Audience: Do you have a study plan or some sort of document we might be able to look at if we wanted?
Speaker: Yes. In fact that historic snag paper is currently in review right now at the journal.
Audience: Just a comment. What you’ve shown is some wonderful work, if you want more information, a lot of this looks like the work the Northern Fire Lab in Region One, Missoula has done for a period of over 20 years. Steve (Inaudible) that’s his first name, you know who I mean. They’ve had fire models for Eastern Montana, Central and Northwestern and now Northern Idaho for up to 25 years. I’m always going back there and getting information from their publications and fire models they’ve got because I can apply that to most of Eastern Washington. Get rid of the strong maritime area and we’ve got a lot of similar series and habitat types and it works very well. At least for formulating ideas. You know so until this is all done, you have some information that’s available which you can make some interpretations from. Is that a fair statement to make, do you disagree with it at all?
Speaker: No, in fact we’ve worked with Steve. And just for information for you, the past two years we’ve been working on Colville, and Puebla Canada, and we did a fire history for that area. Mixed severity. They had hemlock, spruce, cedar. Do you believe this? We found fire-scars on cedar trees?
Audience: First, I want to echo the compliment. This is excellent work. One thing I’m wondering about is given the fires in the riparian zones is there any way you can look through your reconstructional work, did you think you had more slumping more sediment in the streams and with the cessation of fire, could it have grown up and you had less slumping. That to me would be reflected in removal of the gravel that was there, so you’d actually have less sediment.
Speaker: No…it does bring up a point that several years ago we proposed. Since we found disturbance in trying to compare current and historic conditions. We thought it might be worthwhile to propose how to current stream flows compare to historic stream flows. That would be interesting.
Audience: My guess would be that with all this extra vegetation, the stream flow would be less.
Speaker: Yes. In a sense, water and salmon issues are hot, hot issues.
Audience: I’m also wondering if this is purely a question, I don’t know whether this is true or not, but with less disturbance in you riparian zone, less smoke, you would get less addition of new sediment, which means the existing sediment may be washed down. Which may mean you end up with less sediment. Except perhaps where that would lead to downstream bank cutting. Of course that’s gonna tell you more about streams than channels which (inaudible)
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Audience: It’s also compounded by the number of roads you’ve got up in XXXX and sandstone topography, and every one of those ditches is essentially a new intermittent channel. You can argue that we’ve had a lot more sediment into the streams because of the roads over the last fifty years. Audience: Does that (inaudible) from smoking?
Audience: We’re supposed to find a way to overcome that. That’s my final answer.
Audience: Yeah, and also from the roads and streams you would have finer sediment I would expect.
Domoni: Okay guys is that it? We appreciate it a lot. (inaudible)figure out what we’re doing, call you guys, if we need some additional information.
Audience: Just one more question, the stand reconstruction stuff you’re going to be doing, is it going to be any riparian stand?
Speaker: No. That would be a good proposed project.
Audience: I just wondered, have you proposed any type of geomorphic landscape units for the Wenatchee area?
Speaker: No.
Audience: I might have missed this, but have you mentioned that historically roughly like 110 trees per acre, was there any difference in the riparian area?
Speaker: We don’t have data from that area. The only data we have from riparian trees is the full pulp trees. Trees that were (inaudible).
Audience: While we’ve got the fire experts, do we have a good data to determine whether or not XXXX constraints on today’s fire burning, landscape burning is effective in accomplishing in what nature has done? Are our temperatures high enough, do you actually get the clean out?
Speaker: I don’t know. I don’t know. The thing is…is there fire people here…Fuels? The other thing we were able to detect when we were cross-dating these tree rings and fire years, well we could determine what time of the year the fires occurred. We could determine if they were spring fires or summer fires. And I’d say 90% of them were probably summer fires. And even higher than that. It’s just an indication of when the fuels people want to try underburning they plan their underburning in the spring. And I can see why, it’s much safer. But historically, fires were burning in late summer.
Applause
01:31:44
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Domoni: What I’m gonna suggest, we need a few minutes here to switch a tape, so I’m gonna suggest a three minute break here. So anyone who needs to run to the bathroom can, real fast. And then we’ll move on to our next speaker. Tape 2 00:00:00 00:00:43
Domoni Glass: Next is Bud Kovalchik from USDA Forest Service
Speaker: Wenatchee and Okanogan, too.
Domoni: Okay, from all over. Also, gonna bring us up to speed on some of the riparian work he’s been working on.
Speaker: Thanks for inviting me. It’s rare to get out of the office anymore, that’s the Forest Service, it seems like. Can you hear me okay? The Forest Service leads to stress, which leads to acid reflux, which means my vocal chords are damaged. And it’s really hard for me to project my voice anymore. XXXX put this in perspective, I’ve got into a moose mood since Christmas, because here at the last eight handouts, it’s sixty six days till we retirement. And the moose is my humor as I go towards that joyful event. So I may have a funny twist in my humor as I do this. I gave you a lot of handouts. Kept asking, well what do you want? What do you want? Well last Thursday I found out when they had that big list of hard hitting questions, which would take a week to answer. Put together a lot of information as handouts, I can’t begin to cover it. But it’s there to show you that contrary to popular opinion, that there’s not a lot of information or resources out there, there really are. It’s one thing that irritates me about the Forest Service, is they’ve got three or four people who are very good at riparian, wetland ecology and they’re producing classifications which I’ll show you in a second, but they never use us. So, Enfish and PACFISH came out and we were not quoted, we were not used, and yet that’s the best source of information they’ve got. Forest Service wants simple answers. And if you’re expecting me to give simple answers today, you’re not gonna get it. I’m willing to get simple, but not willing to get unrealistic.
Slide: The Classification of Aquatic, Riparian and Wetland Sites on the National Forests of Eastern WA, (Part 1: The Series)
00:03:02 Okay? My job for most of the last twenty years has been as a riparian, wetland ecologist. Before that I was an upland ecologist and was a co-author on forest habitat types in Montana. I’ve also worked on classifications for Eastern Washington (holds up two booklets) for forested uplands. That also includes the forested pine associations in riparian zones. So I’m gonna pass these around, you can kind of look at them. (Hands them out to audience) I also did a Shrub Step classification for pine associations on the Klickitat River, National
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Grassland, back in 1981. Whenever it was. In 1981 or 1982, I did a backflip (holds up booklet) into the water, and started becoming a riparian, wetland ecologist. That was a real learning curve. It took me two years to learn sedges and wells. But I learned them, and I know them very well. And in 1987 did a classification on riparian and wetland pine associations in Central Oregon. (Hands booklet out to audience) That became kind of the outline, for Region Six. And led to other classifications. That sold the concept to the Montana Riparian Association, (holds up book) and in 1995 they came out with a classification for the whole State of Montana. Beautiful piece of work. (Hands book to audience) So I’ll pass that around. And in 1996, Mount Hood (holds up booklets) and XXXX National Forest (hands one to audience) (inaudible) and in 1997, the remainder of Eastern Oregon in this one, and Northeast Washington (inaudible) (hands other one to audience). Anyhow it works on the Okanogan and Wenatchee National Forest. If you’re familiar with (holds up booklet) Cowardin’s Classification for Wetlands, and Deep Water Habitats in the United States, wonderful piece of work done in 1979, what these classifications all do is fill in the dominance types which is missing, but asked for in this publication. So I’ll get official outline people a presentation saying, ‘how are you doing this with the right amount of classification?’ my answer is very simple. We’re finishing this out. It’s a requirement of a National Wetlands Classification. Then lastly, I came to Eastern Washington (holds up binders) to start XXXX riparian, wetland ecologist, to do a classification for the National Forest and the mountain zones of Eastern Washington, (hands binders out to audience) and three years of work straight, and this was finished two weeks ago. It’s off to U of W, for publishing. My guess is it will take about six months. So there’s your source of information for Eastern Washington. Or at least one of them for riparian wetland zones, that’s composed of about 1700 plots, XXXX plots. One of those books has a set of plot cards, there’s twelve sheets for each plot that were filled out. So it’s got a lot more information compared with outgoing plots that have been done for Upland Plant Association classifications. There’s also about 650 lochs and channels that are described with a brief form. (Holds up diagram) This is in your big handout. I handed it out separately so that you can just get. Whoops, that’s not the one I wanted to show you. I handed this one out because I think it’s sitting sideways, and I couldn’t figure out how to rotate it yesterday at 4:00. Forget that. We’ll get to those as I say a little bit later. Okay? So that’s kind of the introduction. Look at those things. There’s a lot of data. You’re gonna get a look at all of appendices that are in there, which are quota production data associated with forestry plots. And to take a guess, about 700 plots, 700, 750 are coniferous or deciduous: cottonwood, aspen, silver fir, mountain hemlock, XXXX fir, Douglas fir, etc. So lots of information. Very intimidating to a lot of people. Because it’s big, and it’s very complex, but we’re trying to describe an extremely complex resource and it’s an injustice to try to simplify it to the point that it’s ridiculous. I think in the long run, we can do damage in our efforts in trying to do Salmon Recovery by trying to have simple approaches and rules of thumb that apply to everything. That’s been the trend in the Forest Service, and I hope it isn’t the trend in Salmon Recovery efforts. Okay, I’m not going to be able to look at all these slides, because I practiced it last night at 11:00 and there’s too many.
Slide: Introduction 00:08:56
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Okay. I probably hit that enough. You can tell I get peeved by simplistic approaches. I’m tired of that. It is a complex resource. I’m retiring probably because Forest Service has buffers, so why do we need to know anything about riparian wetland zones. That’s all we need to know. We’ve put a line around it. But that’s totally unrealistic because nature isn’t going to quit managing them whether it’s wildfire or whatever. And I can go on and on. The only thing I see (indicates to slide) in terms of information for the people that invited me to be here, is these trees at elevation zones and those timber types associated with them. I’m going to be talking about that. And I hope I don’t irritate any people, but the potential is there. (Slide: Eastern WA Timber Habitat Types: Ponderosa Pine: 0-2500 feet, Mixed Conifer: 2,500-5,000 feet, High Elevation: Above 5,000 feet) And that was a good switch, so no offense. I’m just trying, in this brief presentation, and with that classification, to give people a better understanding of what the functions and processes in riparian zones are,
Slide: No Offense 00:10:30
…all the different stream types, all the different valley width and gradient classes, all the different elevations, all the different climatic zones, we end up with an infinite variation in the kinds of situations you’ve got out there in terms of habitat and vegetation. And therefore, to me, you need more of an ecological basis for performing some stratifications. I think you can get simple, but don’t get too simple.
Slide: Potential Natural Vegetation 00:11:03
How many people have dealt with these classifications that I’ve passed around? Either XXXX or riparian wetland? Do you know what I’m talking about? That’s what I’m afraid of. Probably less than half of the people. The Area Ecology Program in Region Six has specialized in this. Unfortunately in the last few years, we’ve been downsized and we’ve lost two-thirds of our people. But the idea, if you look at potential natural community types of vegetation, we call them Series, like the Silver Fir Series, on that land that has potential of being dominated by silver fir climax, if they can go that long. Given that, you know, there’s interruptions, more so in some series than others, especially the drier series, like Douglas-fir or Ponderosa Pine. And then subcategories below that, you know the fine textured level, plant associations. And those are climax community types. So, my samples, whether they’ve been in upland, or in riparian zones, have been in late seral and climax conditions, primarily. I’m looking for sites that are in the best conditions that I can find. And yeah, I know, we no longer have the influence of fire in there, or the burning by Native Americans, but it’s my best shot at what the potential are for these sites. So that’s the opportunities that can reproduce on these sites, in terms of channel types, Rosgen channel types, fluvial surfaces and the vegetation they’re on. That kinda make sense? Rivers are dynamics and valley bottoms are dynamics, and in some cases, there’s fairly rapid change going on in the vicinity of the active fluvial surfaces, point bars, gravel bars, stream banks, flow points. On the other hand, some surfaces, most the terraces, are extremely stable, and in my samples, have been like they are, very stable, sites essentially the same for many centuries. But, yeah, that stream can suddenly go through that flow that there’s a big a log jamb on the XXXX River, the river goes back to an old channel. That can happen. XXXX, but more often than not, there is stability there. That river meanders through the sites and the vegetation that
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were on them, meander with them. But hopefully it’s a very slow process. It appeared in my work in Central Oregon. What I found in Eastern Washington, is we have extremely robust riparian sites. They really, really tolerate a lot of disturbance, and you can dump a bunch of XXXX on it, and they do their best just to rush back to the vegetation. Much more pleasant to work up here compared to Central Oregon. I didn’t have trouble finding sites to sample. Okay? So does that kind of take care of that?
Slide: Potential Natural Vegetation 00:14:18
That’s a five minute lesson in classification. And these are just some examples of names, XXXX Firs series, XXXX series, meadow series, sedges, cotton grasses, and if there’s two names like there, (indicates to slide) we’re getting down into a plant association within the mountain alder series that has meadow ear dogwood hold down the mountain alder.
Slide: Riparian (Wetland) Zone (?) 00:14:47 What is the riparian zone? If you put a hundred people in a room, they’ve all got a different definition. I don’t think I’ve ever gotten a firm definition from my mind, except that when I go out and sample, I sample all the way from the toeslope of one side, to the toeslope of the other side. Unless it’s something like an old glacial pavement, which I figure is no longer a part of the valley bottom. Then I’ll go down to where I figure, the river, within reason, could eventually be working again on that site next year for a thousand years from now. So I go toeslope to toeslope. The main fluvial problems, riparian XXXX, that are different than this traditional definition of a wetland. Yeah Sandra?
Audience: Yeah, I was just wondering where this diagram came from?
Speaker: That’s from the Twisp River. Just above the forest’s boundary.
So its a real wide valley, and did we put the gradient on that one? Probably about 1% or a half percent valley gradient, the sea channel. So all these zones are exaggeratedly narrow. So this is the present Twisp River, (indicates to slide), that’s a channel. It’s probably elevated up a little bit too high, in proportion. Point bars, (inaudible) is often willow, then you might have an abrupt stream bank jump to something like Cottonwood, Red Ear or Dogwood, a little bit more sediment deposition, the Dogwood’s been replaced by common Snowberry, and Cottonwoods, kind of an isolated chunk of an old terrace, Spruce to Snowberry, here’s an old channel of the Twisp River, still got an E channel running through it, it’s pretty wet, mucky soils, below your Dogwood, Common Horsetail, and then back to the series of terraces with XXXX Spruce, (inaudible) Dogwood, and (inaudible) Snowberry. So in that cross-section, which is actually more complicated than this, there were one, two, three, four, five, six, seven different plant associations, different fluvial surfaces and plant associations, that we sampled. That’s how I sampled. So, I’m gonna talk in fire regimes, they’re talking about this and that (indicates to slide). Different principles apply on the wetlands, and they probably didn’t sample those. That help explain it?
Slide: Four-tiered classification Aquatic, Riparian and Wetland Zones 00:17:46
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Okay, I’m gonna go through this real fast, in fact I’m gonna skip all these.
Slide: Ochoco Mountains, Physiographic Area 00:17:50
‘Cause I don’t think I’ve really got time, do I Sandra? (Sandra’s response inaudible) I don’t think we’ve got time, they’ve got a box lunch, but I want to get you an idea of how I look at the landscape geomorphically, in other words, ridgetop to the valley bottom, the stream and vegetation beside it and the real emphasis on valley segments, valley land types, valley width and gradient classes. I’ll go through this real quickly. I look at it from the very broad (indicates to slide) geologic and climatic aspect, which is Physiographic oriented, and there we’re talking about enforcers charting these sections and subsections. Big chunks of land. Eastern Washington probably has 25 different subsections delineated in them. And for each of these areas, if I were to get funding for the second publication, I’ve gotta characterize the watershed in my mind, for that Physiographic area. Actually, draw it and within it delineate valley segments. This is actually how I sampled. I’d travel up the drainage first, or I’d hike up the trail and I’d sample on the way down that valley segment with those cross-sections across them. And then within a valley segment, whether its V-shaped and narrow, or broad and gentle, like that past diagram, you’ve got valley geomorphology going on. And what that is, is the meander of the stream, its overflow, deposition, and its XXXX characteristics, create fluvial surfaces, each of which had different soil texture and structure relationships, different water tables and different plant associations.
Slide: Headwaters 00:20:08
Okay? This is about an, in Easter Oregon, a series of slides I’ve been using for years. If you start at the headwaters you’re dealing with a Rosgen A3 channel, with Grand Fir up on the immediate banks and toeslopes quickly changing into the Grand Fir or Douglas-fir upland. One point here, one reason I hate rules of thumb again, I take every chance I get to blast them, look at the number of logs that meet the Forest Service criteria (indicates to slide), 12 inches in diameter, 35 feet, is that correct? The right one? I played around with that on this slide and what I can remember is a 500 pieces per mile, my estimate, in this, along this Rosgen A channel. That’s a lot different 20 to 40 pieces that I’ve seen as targets. And I guarantee you that if we have targets that low, in these kinds of steep systems, what we’re gonna, we’re gonna blow them out. (Inaudible) Okay, so we have to have realistic targets, based on what? Geomorphic principles, the kinds of vegetation that those fluvial surfaces and surrounding forests can support.
Slide: Intermediate Elevations 00:21:27
Go downstream, I’m not showing you all the slides across here, but it changes into a wider valley, a hundred feet across, two, three, four percent down in gradient. It’s got a Rosgen B3 channel. And mountain alder on the streambanks and around the banks of any overflow channels. The prominent thing you see, which is why this slide is here, is either Douglas- fir/snowberry, (indicates to slide) or ponderosa pine/snowberry as the potential natural vegetation on all the terraces. Douglas-fir/snowberry is just a few miles behind us upstream. People will say, ‘nah, that’s not riparian, that’s not wetland because that Douglas-
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fir/snowberry heads up that toeslope.’ Yeah, the vegetation is very similar, but the thing is we are sitting in the valley bottom. You can barely see it, but the old channel is over here (indicates to slide) it’s pretty much filled in. And I guarantee you, some day, that channel’s gonna be back there with it’s mountain alder XXXX in the picture. So do we deal with thirty feet and a hundred and fifty feet from the streambank for a buffer? Or do we deal with thirty feet to a hundred and fifty feet from where the stream can be in the future? That’s what I think a buffer zone should be. I also don’t think buffer zones should restrict logging. I take a medium position, on where I think we’re foolish, if we put on buffer zone and think we’re not gonna have a change in them. Nature will do it for us someday.
Slide: Low Elevations 00:23:02
Now further down, to characterize watershed. We’re heading out into the Big Basin country, in the South-central Oregon, with a different geologic type now, it’s XXXX and tough, the valley’s very wide and flat. This big E channel meandering through it. The whole valley is covered with willows and sedges.
Slide: Other Physiography 00:23:28
If we take a different route out of the Forest Service ownership, well, we’re still in it, this route we went north into the Prairie River grassland out of the mountains, characterized being XXXX very dry country, down cut to the XXXX creates situations like this. V-shaped, mountain alder on the streambank, ponderosa pine at the, at it’s last gasp and very scattered on the adjacent toeslope.
Slide: Trout Creek Watershed Republic Ranger District, Colville Nat’l Forest 00:23:59
And this is why I handed out this thing (holds up sheet) the one sheet, ‘cause I couldn’t straighten this out at 4:00 yesterday. This goes up into Eastern Washington. This is in the big classification I handed out. As the example for geomorphic stratification of the landscape within one mountain range. And the sequence of the valley segments as you go from high elevation down to the forest’s river boundary. And since that’s sideways, I’m not gonna talk to it very much, but just notice you go from the uplands, that’s the subalpine fir zone, down through a Douglas-fir zone eventually down into zones where Ponderosa Pine, briefly, at least the southslopes, then it heads out off the Forest Service land, you don’t see it, into the Big Valley Grange, north into the Kettle, where it’s shrub steppe vegetation. And it’s totally different yet it’s not shown on here. So again another example, though it’s kind of humorous, once I put this together, I took a Trout Creek from Oregon, and I took a Trout Creek from Eastern Washington, I guess the outside’s probably 60% though. There’s so many trout creeks out there.
Slide: 00:25:30
Okay, now to the meat of what I want to get into, that’s this. I drew these lines on here at 11:30 last night, I’m proposing, instead of three elevation zones for all of Eastern Washington, which is what I think I’m hearing is happening, I’m proposing an alternative. I
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don’t know if this is what it ought to be or not, but in a very short period of time, this is another way I came up with looking at a way of stratifying the landscape that is ecologically based. And what I’ve done, over here (indicates to side wall of maps) I’ve got all kinds of maps that we’ve done in Eastern Washington based on some principles of (inaudible) natural vegetation (inaudible) over in the Seattle area (inaudible) west side of Washington, a really very intelligent guy (inaudible) and he developed a system which we applied in Eastern Washington, in which we take things like XXXX annual precipitation, and XXXX annual temperature, and things like XXXX moisture, and how XXXX water accumulates going down slopes XXXX numbers assigned the closer you get to riparian zone data, XXXX, (inaudible) and (inaudible) models, potential XXXX, XXXX forest, in Eastern Washington. I’ve got to warn you, these are good for broad scale planning, they are not good for project planning. You can not go to a spot XXXX and be certain you’re gonna find it there. But on the broad scale, these things are pretty good. What we discovered as we went on, XXXX additionally, of real resistant to get into this process, ‘cause I like to do it hands on, rather than have a machine draw lines for me, ‘cause I knew the failing factor in this was going to be soils. But if you look at it real simply in Eastern Washington, most of it was covered by glaciers, at least on Forest Service lands, and if you got XXXX, especially if it’s fine- textured, that’s a water storage medium. A Flute along the ridges, maybe all the slope, in a lot of cases. If you were ground down to bedrock by the glaciers, you got thin soils, quick run-off, and those sites are very dry. So a model takes the north slope and an elevation and an aspect and topographic moisture and temperature, precipitation model and predicts it ought to be subalpine fir there, or it predicts, it ought to be Douglas-fir there, but in actuality, if its XXXX, it’s subalpine fire, if it’s ground bedrock, it’s Douglas-fir. So we’ve got a 30% error in those maps from that alone. And so we finally convinced the supervisors that that was the case and instead of going forward and gaining that extra 15 to 30 percent that we could with some kind of a soils map, to reflect some pretty basic principles, the project was dropped. So broad scale planning, roughly, the accuracy is probably about two thirds on these things, they could be made a lot better. And these are strictly uplands, there are some XXXX built in for XXXX drainage, so (inaudible) for instance, you’ll see subalpine fir in yellow, way down the drainage XXXX, in fact this really surprised XXXX, (inaudible) so subalpine fir follows those drainages and continental climates for a long, long ways. He said, no it can’t be any more than 300 feet in elevation, because that’s what he saw on the west side. Because subalpine fir goes down to about 1500 feet from the large yellow blobs which represent the XXXX. And then below that, spruce takes over. People say spruce and Spot Fir represent the same environment. No. Spruce goes down another couple of miles and then finally into Douglas-fir, which we don’t really have a lot of on the National Forest Land within Continental climates. So there’s an effort to get culvert drainage in there. It worked fairly well, but it’s somewhat imperfect too. So back to the original thing I was gonna talk about. On the maps I handed out to you, you’ll note, this is just rough, but last night I drew I line down here (indicates to slide) and I drew a line over here. This huge central area, from the bottom of these slopes of the Cascades, are labeled Continental Climate. This area up here, I labeled Inland Maritime, and this zone down here, Strong Maritime. Okay then I labeled what are the common, dominant series, the dominant series, the climax series within each of those zones. And over here, revealing XXXX, lots and lots of precipitation. If you look at that legend, we’re talking 70 to 270 maybe the top of Mount Rainier, I doubt it. I don’t know why that 270 is up there, but lots and lots of precipitation. And what dominates?
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Mountain hemlock and silver fir. Go over here (indicates to slide) to the next drier climatic zone, what dominates there? Western Hemlock and Western Red Cedar. And a little bit of subalpine fir up above the 5000 elevation contour.
And in the middle, we’ve really got two things going on here, up in this area lots of subalpine fir, kind of the middle-moderate and higher elevations, huge amounts of Douglas-fir on the uplands, and then Ponderosa Pine shrub steppe down below. In the riparian zones we’re dealing with this transition from subalpine fir, XXXX spruce, to Douglas-fir and eventually out the shrub steppe. And cottonwood mixed on the active fluvian surfaces on the bigger drain, bigger rivers, that are capable of producing the sites for cottonwood to reproduce on. A little bit of XXXX I guess, is I put that next set down here. (Indicates to slide) There’s something going on here, in which it’s not quite continental and it’s not quite strong maritime. This is the Swauk creek grange, that they were emphasizing in the previous talk. So I changed that a little bit to say Swauk fir, grand fir and Douglas-fir. That’s the normal sequence going out of there. And if you’re up in this zone, I changed it a little bit by putting XXXX at extremely high elevations. So what’s the point? If you use that zero to 2500 foot, 2500 to 5000 foot and then 5000 foot and above, you’re really mixing apples with elephants in terms of the kinds of vegetation that can grow on there. Also, you’re mixing very different kinds of hydrologic regimes when you go from the huge amounts of water that come off the Cascade Crest and the small streams in the very dry climate and the low precipitation associated with that Continental zone. And over here, somewhere in between. What else do I want to say about that? That’s enough for now, I was really glad to see their presentation because it helps explain in fire regime, at least part of that area that I’m describing here. I think most of what you heard is from that continental climate zone with that unknown grand fir zone associated with Swauk Creek. Sandra?
Audience: Inaudible
Speaker: I’m not sure I understood the question. Where were you?
Audience: Well we were in the Colville National Forest. And we were about 3400 feet above (inaudible) So we were finding that the elevation thing was breaking up into a habitat that wasn’t even describing what was really there on the graph. And I just saw a potential for a very big problem.
Speaker: You didn’t see a plant association? You saw a vegetation that didn’t match plant associations within the classification?
Audience: (inaudible) State Rules.
Speaker: That was in the State Rules? Are you talking about my classification or the State Rules?
Audience: I knew the plant association that I was in, and then if I put that association into the State Rules, it would have the wrong XXXX, the wrong…
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Speaker: We’ll get into that.
Audience: I think Rick has the same scenario…
Speaker: Hold onto the question until we get into the next, or the next-after subject, is that okay? My answer is, I’m not surprised. That’s why I’m preaching. Sorry. That’s what I’m doing, preaching.
Okay, what else. Just on fire regimes. You know here (indicates to slide) what kind of fire regimes do you have? Very long and well standard replacement fires. I’ve got some descriptions in my guide that are kind of a mixture of McGee’s book, plus site index trees, you know, what were the age of the oldest trees we have? And made some estimates. They’re not hard science. They’re not hard science. I didn’t have enough trees and enough ages and I didn’t have any scars, but you know, I made some estimates. Now here, it’s more about what the previous presentation was about. Over here, again we’re somewhere in between. I’ve had the advantage here in riparian zones, XXXX hundreds and hundreds of soil beds (inaudible). And it was amazing how many times I could be stopped by an old log, which was an old growth tree, I’d bring up charcoal with it, or I’d go over to the stream and I’d find big logs, criss-crossed through that stream, way down under the water, who knows how long they’ve been there. I had flown down in Central Oregon, with a (inaudible) saying that a guy’s digging a water well. And this was in the Missowa outblast area, he came and got me ‘cause I always stayed there in the XXXX area, there’s a XXXX River in Central Oregon, he took me to the hole and said, “Look at this.” And there was criss-crossed lodgepole pine, that might have been XXXX down during the Mount Muzoma eruption. So that bark, the needles, were there, including the mushroom, anyway, the cones were intact and XXXX lodgepole pine was intact. We cut cross-sections and very quickly they butterflied because the spring let loose, the centergrade was (inaudible). XXXX trees last a long time. And my feeling is that in this area we have a huge number of standard replacement fires, for 1880 to 1920 something. And roughly 70% of the landscape was burned. And a lot of those fires went through riparian zones. Including the Sierra hemlock stands. A lot of places they didn’t, but they’ve been logged since, naturally. And I feel there that was an immense percentage of the acreage in this country, because it’s very high precip, that was old growth. A lot of (inaudible) based on the 1930’s and 40’s photographs. Why? Because I dig down into the soil and I find all these old hemlock and cedar. So I feel we’ve had slight changes in response to that. The way I explain going out there into an Alder wetland, with sedges underneath, the sedges where the beaver XXXX would flow up, those big fires burning through it, shrubs came in, the beavers came in, they built dams, they raised the water tables XXXX and changed the site eventually from cedar or ladyfern, something like that in those valley bottoms, into very wet series and plant associations with very high, wet soil. Very high water table and very wet soil. Is it still cedar and ladyfern XXXX? No. What about all these darned XXXX and wet logs? No. Because we’ve changed the site potential which have changed the soil and water relationships. We’ve got miles and miles and miles of present wetlands, riparian wetlands, that were once cedars and western hemlock bottoms. So I don’t know. It’ll be interesting how that scenario compares with what you guys find in fire-scars.
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Audience: One thing we did notice, in some of those areas, were, you talked about the hemlock/cedar, especially in there, closer to the bottoms, but on the sideslopes we saw a large, a fairly significant XXXX of old larch. Apparently it could withstand some of the more severe fires that XXXX.
Speaker: Yeah, more slopes probably tended to be long intervals, tended to drift towards cedar and XXXX slopes, Douglas-fir, (inaudible), more frequent fire intervals was probably a pattern in there, I feel like the bottoms tended to be, except among higher, drier terraces, fairly resistant to fire. And there also tend to be quite a bit of wetland species that won’t XXXX between them.
Audience: So the fires in between, there was, you know, we mapped a lot of fires in the Colville area, going back to the 1600’s, but the large standard replacement fires have occurred in the 26 and 29 that they’ve mapped. We don’t agree with them. Those fires occurred in 1917. The large standard replacement fires. Prior to that, we also mapped XXXX area, and where those two to three hundred years of fires we mapped, there was one large fire that covered the whole area, 1831, the whole area. Prior to that, the fires were often mosaic, it’d burn a thousand acres here, go over here and burn a thousand acres, go over here two thousand.
Speaker: Lots of huge areas. Not compared to big ones, but the dry ones.
Audience: (inaudible)
Speaker: But of course we have lightning, XXXX, steam donkeys, all kinds of things around in that area (inaudible)
Audience: In the intervals, overall, like you said, are much longer up there. They range from eleven up to almost 40 years.
Now I gotta get to, it’s almost twelve, I want to go forward to…
Slide: 00:43:04
…this. Okay, this and the following tables are taken out of appendices from the classification. All those appendices were oriented (inaudible) I did the unthinkable of mixing everything across all of Eastern Washington. But I was emphasizing series in this first classification. This first and follow up classification that I never had the resources, or the time or money, to get it done (inaudible) I did take the data for elevation and I did some XXXX on base area, but I did a crude cut, like with these lines (refers to previous map), assorted elevational data, and I just wanted to show you again the differences in the dominant species with this late seral, climax stands that I sampled within the various climates: strong maritime, continental and inland maritime. This isn’t perfect but all I did was I (inaudible) and township ranges, and sections and threw them one way, and township ranges and sections and threw them the other way and there’s a certain amount of noise in this. (Indicates to slide) there’s the averages, and the ranges of elevations for these various series.
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(Inaudible) from highest elevation down to below us. The one thing that’s out of place is this grand fir. The reason it’s higher than hemlock and cedar, is that because of they picked up the higher elevation box like along a swamp thick. And it’s just in the way I sorted the data that makes it appear that this occurs in the higher elevation XXXX moister sites than cedar and hemlock. The usual progression is at the timberline we’ve got mixes among Hemlock and subalpine fir, just depending on the site. And there isn’t much subalpine fir in strong inland maritime climates, so it’s not highlighted. Then you drop down into a XXXX zone, of silver fir, Engelmann spruce is scattered and it’s pretty unusual on the XXXX wetland sites, then you dip into Western Hemlock, continuing down the valley bottom, some western cedar and grand fir and then on the larger valley bottoms, you’ve got XXXX, XXXX and such. Continental climate, much different species relationships going on. Within it’s zone, XXXX is extremely high, subalpine fir, XXXX are huge elevation range. Look at XXXX range, what we were talking about earlier. Engelmann spruce, in riparian zones, is below the XXXX fir, XXXX wetland sites, most are extreme elevation, 70 to 100 feet or higher. XXXX is there because, and Grand Fir, right on top of the Western Cedar. That’s there, because once in a while in exactly the right environment, you’ll find a strangle of Western Red Cedar, like along Lake Chelan, or along 4000, 4,500 feet. And there’s a fair number of plots, 25, because whenever I’d see one of those, I’d stop there. So it’s really disproportionately oversampled and the reason I stopped then is because Cedar doesn’t occur in the Continental climate zone. So see what’s going on there? It’s extremely rare in terms of the land area. We’re talking a fraction of a percent of the land area. Abder is there because of the Swauk Creek areas. It’s just the way I sorted data. Some of the Grand Fir out on that transition from strong maritime kinda got thrown one way, and some of the Grand Fir got thrown the other. But down in the southern, eastern two-thirds of the Wenatchee, there’s significant Grand Fir stands and is it continental zones? is it strong maritime climate? It’s something in between. And then eventually you get down into a little bit of Douglas-fir in the foothills, and the Cottonwood, XXXX. The only handout I got was high elevation, so let’s get on XXXX elevation. The Continental zone, the Larch, some Douglas-fir and XXXX Spruce, it’s the high elevation timber type. And over here, subalpine fir and mountain hemlock, really fit in. Silver fir goes up that high, only because as you have XXXX from the strong maritime climate, it goes up in elevation to find a site it can grow on. And most sites are more continental like in Chamfer Basin area, they’re more continental to me than strong maritime. So that stands a really rare. I sorted into the strong continental climate but they don’t really belong there. And then over here too, what goes up over 5000 feet? Mostly its the subalpine fir and Engelmann spruce and western hemlock sneaks up there a little bit.
Slide: 00:48:58
Let’s just take a quick look at basal area. And there was a target of 285 square feet, site one for over 5000 foot, timber type? We’re looking at the strong maritime climate. We’ve already said subalpine fir and mountain hemlock XXXX above that elevation, as a series subalpine fir is very rare, or unusual. So all they put was mountain hemlock and it averaged 157 square feet of basal XXXX. And I wish I had the number of plots down there, but 40 or 50 plots, something like that. So it’s way way below the target. What happens at intermediate elevations in strong maritime climates, versus the target, I don’t know, I didn’t
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get the target from you, but in the silver fir zone, you’ve got some pretty significant basal area.
Slide: 00:50:15
Anyway you could look at these things at your own leisure,
Slide: 00:50:20 when you have hours of time. In the continental climate, primarily its subalpine fir, about 5000 foot, a little bit western hemlock, when you go up to fifty-three, fifty-four, fifty-five hundred foot sometimes. Not western hemlock, just jumped to the end of the maritime. Just the subalpine fir, above 5000 foot in riparian zones, but it goes way down to the low elevations, so make of that what you want to. With 203 square feet of basal area versus, on the average, versus 285.
Slide: 00:51:03
And this is the inland maritime. Some Sedofom fir in high elevations. In maritime area it doesn’t go way, inland maritime, doesn’t go way down into the valleys because you’ve got Western Hemlock and Western Red Cedar. Instead, doesn’t have that site to go down. It doesn’t follow cold air drainage much more than a couple hundred feet in maritime. Like I said, a little bit of Western Hemlock gets up above 5000 foot, but that’s more in line with 285 square feet of basal area. But still, this is more common in that elevation zone.
Slide 00:51:50 Slide 00:51:51
Here’s some of the ranges. I didn’t sort this XXXX at all, again. But there is some sorting, just on the XXXX of like mountain hemlock, for the strong continental zone. That kind of thing. What point do I make about that? Again, elevation, there, 157, in the strong maritime climate seems to be what my data is reflecting. 200 feet, 203 square feet XXXX Subalpine fir in the continental and maritime climates above 5000 foot. There’s all kinds of ways of playing with your data. This is a really XXXX way of doing it. I did it in a big hurry, but it’s indicating that maybe those targets are off. Another thing that’s interesting, is look at the range of plots. And, I kind of worry about numbers like that, (indicates to slide) it’s just a couple of trees, probably housing something like an Engelmann spruce (inaudible) Saw Leaf Sedge, so an Engelmann spruce/Saw Leaf Sedge habitat, XXXX plant association. Very wet, standing water, well into the summer between crowns, that the Spruce are growing in. Some of these sites have, some of these plant associations have severe stocking restrictions. On Grand Fir, there was the highest number of, like on Swauk Creek, of Grand Fir/Vanilla Leaf plant associations, good soils, a lot of ash, very productive site XXXX, it can produce some pretty extreme basal areas in some of these sites.
Slide: Summary 00:54:04
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So in summary, don’t get too course-scale. Look at the environment. You do have a classification that can help you do that now. Lots of data there that you can massage. It’s not the most scientific data. I was collecting twelve pages of information, so I went through trees, in a big hurry. And I only have three, four, five trees per plot that I could go on for site indexing. But I did screen prisms, ice bases, I did screen prisms for snags, whatever good that is, I did put in rectangular plots, and then plot for logs. So log data is probably fairly good within the realm of was I random in selecting the plots. It’s at least good for an index. And that was it. Another thing I wanted to touch, really briefly, is to look in your handout, at the table on logs, which I think was the next to the last, third page from the end? I didn’t have a slide of that. So you’ve got tables for each series. It’s XXXX by plant association, but the data gets more fuzzy with the fewer plots you have. I wouldn’t do it for all plant associations, but maybe those I had less plots in. Are you on the right page? You see it? Third from the last? Now if you look at the total for the classes, the very highest average percentage is 12.4% for the silver fir series. Which makes sense, that’s probably the best site that we’ve got in Eastern Washington. XXXX places there XXXX some trees. The Forest Service, a year, two years ago, came out with a XXXX gave us, maybe it was the west side, 20%. Ground cover logs XXXX. Is it possible? Jan Henderson, who I mentioned, helped develop these methods for coming up with XXXX vegetation, got 4,500 plots. Usually hector sized plots, many of them in old growth Douglas-fir forests of Mount Baker, Snoqualmie National Forest, he couldn’t come close to 20%. So if we’re gonna make rules of thumbs, let’s be really careful and not make rules of thumbs that are unattainable. Or in the cases where there are a number of pieces along streams, depending on the stream and the vegetation zone that you’re in. XXXX, they’re way under what nature can produce. What nature’s much more, yeah there’s streams, there’s valley bottoms, there’s vegetation, developed largely near natural regime and if you want to target what’s best for Salmon production, we need more logs per acre in those streams. Sandra?
Audience: I’m not sure I’m following you right (inaudible) ?
Speaker: Well, I’m just emphasizing Jan Henderson’s had lots and lots of plots. Jan’s really scientific in the way he goes about things. A hector plot is big. And he measured every log in those 4,500 plots. So he’s got very reliable data. And those plots were selected randomly within late seral, old growth conditions by and large.
Audience: So you’re supporting that?
Speaker: Yeah, so he’s supporting my observations. When I learned that 20%, and said ‘my God,’ and called him up first thing and said ‘what kind of figures did you get?’ and he said, ‘well, that’s really (inaudible) like you were getting’. So, I don’t know who came up with the figure, who ran with it, what should be done now (inaudible) probably (inaudible) which (inaudible). Yeah, Chad?
Audience: Do you want to follow up on that, I have a different question? Given that you’ll be retiring soon, is this data computerized and (inaudible)
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Speaker: Yeah, in ’97 Ken XXXX for Colville National Forest and myself went from whatever our, we had a Paradox database, we went to an Access database and we integrated all the various sources of information to a common data set. So, I’ve got 15,000 plots, 11,700 and something are tied to a key plot number on a GIS layer, you know, XXXX number sequential, everything’s tied in through that plot GIS layer and you can query all 75 tables, whatever they are, through that GIS layer.
Audience: Excellent data. Congratulations XXXX, I wish you XXXX still around
Speaker: When I say, 15,000 XXXX, and they’re varying quality, some are just field forms, others were you know, lots of data, like on riparian wetland zones. A couple thousand of those have extremely good timber data. Those are mostly XXXX, minor kind of marginal for timber data, but for (inaudible)
Audience: (inaudible)
Speaker: Probably down three inches. At a five foot length. And in general I do preclude things like Alder, ‘cause they rot so fast, don’t bother? Is that reasonable?
Audience: Early on you said that, that you weren’t precluding (inaudible) it’s not difficult to confuse me, but I am.
Speaker: I know, he lives in Colville, so.. (laughter)
Audience: But what I thought you were presenting is largely here, kind of undisturbed potential basal area and undisturbed in terms even of (inaudible) Some XXXX that’s been produced, so, and then the fire guys are talking about, XXXX years, at least in the lower elevation and stuff. So I’m confused now about the message that you’re sending. It seems that you said we will allow activity there, and that you recognize the probability of at some point, some sort of disturbance, but then the targets would seem to be advocating our only undisturbed sites.
Speaker: Well, I don’t say I’m advocating those exactly. When I started the Forest Service, I was an environmentalist and I started get that, receiving it from the environmental community which I was a member of, slander, so when my data was better than theirs, I quit. So since then I’ve been straddling with the old growth. I’m still an environmentalist but I realize that we have to manage the landscape. You can tell from my analysis of buffers, I think that’s totally inefficient, XXXX our own ideas on how the buffers should be managed and it can include timber harvesting. XXXX may not timber harvest anywhere, where trees’ roots are touching the streambank, or a place that can become a streambank, but (inaudible). I see the opportunity for harvesting, but if you’ve got specific agendas that you want to do there, like increasing the amount of shrub cover on a streambank or increase shrub cover for wildlife XXXX. Within that data, given what they said about fire regimes, some of the data, especially subalpine firs and spruce is in that continental climate, and it reflects you know, the fire regimes, the areas that XXXX samples, Swauk Creek and
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XXXX, that data also reflects the stands of mountain hemlock, silver fir and some of the wetland western hemlock and western cedar in Colville, that are old growth. And we’ve had those logs laying there for centuries. They were buried into the ground for centuries, sticking through the (inaudible) functions, processes and structures XXXX. My point is (inaudible) in the case of those A channels where I see maybe 500 logs XXXX the creek per mile, where I see 500 logs per mile, which one do we want to go with ? Do we want to go with 20 to 40 or XXXX and end up destroying that valley XXXX associated with that aging XXXX, or the channel itself? Or do we want to go give some opportunity that somewhere between that 20 and 500? Whatever we do in riparian zones, in terms of XXXX, we have to make sure that we have an adequate number of logs for that stream. Then the salmon, XXXX spawn (inaudible). There’s other streams, the big rivers, if a log falls in, it gets pushed up to the bank, but it doesn’t move down stream into a log jamb, There’s an infinite variety in valley width and gradient classes and stream types that are associated with XXXX vegetation that grows along those streams. (Inaudible) that problem is really bothering me, but you can’t treat subalpine fir zones, like you do (inaudible). Basically.
Audience: (inaudible), the kind of streams you’re talking about, that may be very very (inaudible) the lower end of Mill Creek in Colville, mid-sized streams versus the very small XXXX?
Speaker: Yeah. I haven’t got any XXXX, except I’d like to see more ecologically based stratification. And starting with those three zones. XXXX handouts in a more precise way (inaudible)
Audience: What functions, I’m just trying to think this through, we spent quite a bit of time on high elevation stuff, and generally small streams, (inaudible) in maritime…What would you envision the functional requirements of such heavy basal area to be terms of downed logs and standing stuff at higher elevations with very small streams?
Speaker: In smaller streams at high elevations versus deep channels out in the open?
Audience: Yeah, basically, I chose high elevations because that’s where you gave most of your heavy basal area
Speaker: In the A channels like that one I showed with lots of logs, we need to reduce the XXXX gradient and the energy associated with that stream either normally, or especially at peak flows. And it does that either by sorting the XXXX, what’s the proper word, the terraces, so you’re reducing the effect of gradient, or logs do that for you. They build up dams, flat spots, pools, another little dam of rocks and logs, XXXX so it’s effective at controlling the energy of the creek, especially at high flows, XXXX most streams may or may not get XXXX. Down in lower elevations, or even in the V-channels, they are also important in functions and processes in the streams, XXXX streambanks, anchor locations, but there, they’re also creating fish habitat, undercut pools, hiding cover, that kind of thing. They’re less important at that point, than keeping streams from growing out, but they’re very important XXXX
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in terms of fish habitat. They are important, we all agree on that, for processes, functions and streambanks, it’s less important (inaudible).
Domoni: I hate to cut this off, sounds like a good conversation, but maybe we can continue it over lunch. I want to thank you for your presentation, it was very interesting (applause)….can you give us an update on the status of lunch (laughter)….
Tape 3 00:00:00 00:01:06
Speaker: …presentations this morning. I’m interested in what you all have to say. I’ve put a slightly different approach to this. What we have is a lot of different pieces of information and knowledge and the next question is ‘how do we start pulling them together to see how they interact with each other?’ So for that we used a mixture of science and technology. The science starts with the systems concepts that are evolving these days of which ecosystems is a part. And then looks at the current condition of what we know about how forests change over time. And also, some changing understandings and paradigms of our forests demand and forest wood use, that I’ll get into. I’ll be talking about that quickly and then show how we’re using technology to help approach some of these issues. And once I get into the technology in general then I will turn it over to Jason Cross, who is a graduate student at the University of Washington who is working on specifically on modeling various riparian area functions. Now I’ll start off and I’ll go through this fairly quickly. This work is being sponsored by our congressional delegation through the landscape management and the rural technology initiative projects. First thing I want to do is talk a little bit about systems. Almost anything can be subdivided and made more and more complex.
Slide: 00:02:48
And people began realizing that there are just too many interactions. It’s difficult to analyze them all, so the systems approach looks at a combination of understanding the interactions…
Slide: 00:03:01
…but also grouping them. So that you work with groups. And these groups could be anything from individual atoms and molecules and looking at how the molecules interact to such things as looking at how individual solar systems interact to form a galaxy. Now what the way, the approach we’ll look at it is, this, these would be individual trees here. They can be grouped into stands. We can manage the individual trees, we can manage the stands….
Slide: We Group Things to Reduce Complexity (Systems Approach) 00:03:32
.. we can begin looking at landscapes. We can be grouping those into larger regions. Well the whole systems idea recognizes that you can look at these at different levels and as you go to a larger level, you aggregate up. And by necessity,
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Slide: These Groups Can Be Arranged As Steps in Hierarchy 00:03:50
…when you aggregate up, you end up with a hierarchy here. But the secret to the systems approach is recognizing certain behaviors of the hierarchy. Among others, is that you’re always going to get variation between each level. And that variation is caused because you generalize from one level to the other.
Slide: 00:04:14
Then the whole approach in systems management is to start with a basic system where you make your best scientific understanding of the relationships, recognizing there’ll be variation, and then you do sensitivity analyses to determine what if XXXX gone incorrect in one and another, and then you continue with what some people call monitoring an adaptive management but it’s the same as the continuous quality improvement approach to through time improve your understanding of the relationships.
Slide: Outdated Scientific Paradigm 00:04:54
Now with that as a background, I also want to cover a couple of scientific paradigms. Up until about 10 years ago, the predominant ecological paradigm was that the forest existed in a steady state. And this was, quote, the natural condition at the time that Columbus came to the New World. In fact, my first ecology course, I was taught, this was in the 60’s, that weeds were just about to go extinct in North America when Columbus came here ‘cause since there were no disturbances, there were no places for them to be. Now, we’ve come a long way since then. Now, as long as we assume that this was a closed system, with trees dying and others replacing itself and all species living in just this forest, we could manage these through selective cutting.
Slide: Complex 00:05:47
We could also, basically keep large areas aside, and this would be the place where we would protect our native species.
Slide: 00:05:56
Now, as early as the early 1900’s, people set aside these areas, like this that would be perpetually in this, quote, climax condition. This was an area in New Hampshire that was set aside in about 1900 by the Harvard Forest.
Slide: 00:06:12
This is the same area as it looked in 1939. In 1938, a hurricane came through New England and blew over half a million acres of forest. Now the interesting thing is, a reconstruction study in this showed that in fact, those pine trees originated after a hurricane of 1665. So that the forest was constantly going through this change.
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Slide: Natural Disturbances Always Have & Will Occur 00:06:35
As we begin looking around, we see various disturbances
Slide: 1985 Tornado 00:06:39 occurring. Slide: 1989 Hurricane Hugo 00:06:41
Tornadoes, hurricanes,
Slide: New Scientific Paradigm 00:06:46 hurricanes followed by fires. And we now accept the forest is very dynamic, constantly changing among different conditions, with growth and disturbances. We can classify the condition and changes in different ways. This is one I’m just gonna use for this discussion. Where we go from the open to the dense understory savanna complex and back and forth with disturbances in growth.
Slide: Savanna 00:07:08
Now, just to give you an idea. This is the savanna structure. And this is, used to be common in much of the world, and is very uncommon right now.
Slide: Open 00:07:15
This is the open structure. This and the savanna are one of the, two of the three most diverse structures in terms of species. The other one being the complex structure.
Slide: Dense 00:07:24
This dense structure contains relatively few species, or relatively little understory, that’s when the forest grows up
Slide: Understory 00:07:32 and excludes the understory. This has been your understory condition, for obvious reasons.
Slide: Complex 00:07:37 and then your complex forest.
Slide: Some Species Depend on Each Structure 00:07:39
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Now the significant thing is, each of these is useful in various ways. Different ones have different species that use it. Different ones have different behaviors as far as influences on the riparian zone. And we don’t know what all of those influences are, but as I’ll show you, not only does the difference important, but the way it changes is also important.
Slide: Riparian Zones Can be Delineated and Treated as Separate Stands 00:08:00
Now, if we begin looking at just the riparian zones, we can recognize that the forest in there actually existed in a variety of conditions. Not only that, Slide: Criteria for Sustainable Forests 00:08:12 but it was changing over time. And if we want a variety of things from the, our, forests, and this is the Montreal Process Criteria for Sustainable Forests, we can begin looking at how do we manage our forests to provide this large variety of different conditions?
Slide: Wood Growth Exceeds Consumption in the World 00:08:30
Now, another change in paradigm, contrary to earlier beliefs, we are not running out of wood in the world. And part of our problem is that with the excess of wood, in the world, it’s very difficult to thin our forests because it costs very much.
Slide: Forests Can Be Managed Different Ways: Plantation and Reserves 00:08:50
Now, people have put forth two different ways that we can manage our forests in the future. One is to go toward intensive plantations and then set aside the reserves in other areas. By the way, if that were carried out completely, we would have about 90% of the world’s forests in reserves. Eastern Washington and elsewhere and not only socially, but ecologically and financially for the people trying to manage these intensive forests, there would be problems with that. So the alternative paradigm,
Slide: Forests Can Be Managed Different Ways: Integrated Management 00:09:26
Integrated Management. Within each area, you still have room for reserves. But much of the forest could be managed in a way that you mimic, avoid and recover from various natural disturbances to mean all, to maintain all structures across an area. This doesn’t mean cutting down the complex forest, it means if there’s not enough of it, try to supplement it. Because if there’s a shortage of one structure, there’s too much of another.
Slide: Well Differentiating/Poorly Differentiating 00:09:53
Now the secret is in the details. Or the devil is in the details. For example, we can have a forest growing and one can be well differentiating and very stable. Another one can be
Slide: 00:10:05 poorly differentiating and very predictably, and these are predictable things, can fall over.
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Slide: Height/Diameter Ratings 00:10:11
And we can measure this by such things as Height/Diameter ratios and
Slide: 00:10:17 diameter distributions.
Slide: 20 Yr. Old Stand, Stem Exclusion Stage 00:10:20
We can do various thinnings if we have too much of a forest in this dense structure.
Slide: Same Stand 3 Years Later 00:10:23
Let me back up just a minute here.
Slide: 20 Yr. Old Stand, Stem Exclusion Stage 00:10:27
This stand is 20 years old, will stay in the dense structure for the next 60 years. This forester did a pruning and thinning
Slide: Same Stand 3 Years Later 00:10:37 and three years later it looked like this. He was able to get a lot more diversity in the forest, rapidly.
Slide: Quality 00:10:43
With thinnings, we can rapidly create large diameter trees, understory, organic matter,
Slide: Selectively Cut 00:10:50 other things that are quite useful. Now another important thing is if we’re going to try to create the complex forest, we know that you have to go through a stage that’s almost like a savanna. In fact it is like a savanna, to get there. So you don’t move straight from this forest (indicates to slide) to this one, but you go through a series of different conditions.
Slide: Stable Overstory Trees 00:11:11 Slide: Unstable 00:11:14
For example, you would go through this condition it would work in that forest, but this one the trees are inappropriate
Slide: 20 Years Since Overstory Selectively Cut 00:11:18
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to get to a complex structure such as this.
Slide: Narrow Spacing/ Wide Spacing 00:11:20
We can also look at some forests have narrow spacings and easily fall over, get insects in them.
Slide: Mixed Douglas-Fir/Western Red Cedar 00:11:29
Others don’t. We can look at other forests, have mixed species, single cohort stands, this is Douglas-fir and Western Red Cedar that provide
Slide: Forests Can Be Managed in Different Ways: Integrated Management 00:11:39 certain habitats. So we can manage,
Slide: Present ‘Forest Health’ Issues? 00:11:43 but we have to recognize the subtleties of the different stands. This zone in Eastern Washington, our present forest, are very overcrowded
Slide: Savanna 00:11:50 where we once had savannas
Slide: 00:11:52 we now have many other trees growing up around that have insects in them, that have fire problems.
Slide: 00:11:57
And this is leading to such things as the ’94 fires and some erosion problems.
Slide: Areas Burned Annually by Wildfires in the Western U.S. 1940-1994 00:12:03
Incidentally, for the whole Western United States, this is the fire situation and its in, the number of fires is increasing. This is because of our fire suppressions here. This is a very common phenomenon we have.
Slide: No touch Riparian Zones are Leading to Insect, Disease & Fuel Buildup and Eventually Fires 00:12:19
Now this was taken by my graduate student Glenn Yallup on the Yakima area reservation. You’ll notice that they have thinned everything but the riparian zones. And notice where the trees are dying from insects.
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Slide: Riparian Zones may not be the appropriate place for continuous insect disease areas 00:12:33 is in the riparian zones. This creates a problem because we, by having the whole riparian zone uniform, we can create problems with a disturbance taking out the whole
Slide: Silvicultural Operations Mimic, Avoid, Recover from Natural Disturbances to Maintain the Range of Structures 00:12:45 area.
Slide: Natural & Social Environment 00:12:46
So if we begin to look at managing, if we look at the individual stand level, it can only be in one structure at one time. If we look along the riparian zone, each reach of the riparian zone would be in one structure, so if we begin managing on the landscape level,
Slide: 00:13:04 we can coordinate the different structures across the landscape, or even along the riparian zone, so as to get some type of balance that will provide the values we want
Slide: Technology Makes Decisions More Site Specific, Cost-Effective 00:13:15
Now the question is, how do we know what to do where either on a landscape or in a riparian zone, to achieve the objectives that we want?
Slide: Objectives (values) 00:13:24
In other words, be it a landscape or a riparian zone, how do we know what to do when and where or if we do nothing, what will be the different objectives and values we want? Now this is the question and the issue then comes to the following
Slide: Analyze? Communicate? Monitor & Feedback? 00:13:44
We have much of the background information. We have growth models as, I’d be glad to discuss, they’re not perfect, but with the systems approach, we’ll put them together and to determine is that our weak link? We have silvicultural operations, we have inventory, we have GIS, we have financial analyses, not shown here, is we also have habitat suitability indexes and we also have various riparian relationships. Being able to put all these together and link them is a quite complex process. Because taking inventory data and putting it into a growth model and then looking at what that means for a habitat, gets to be quite complex in terms of organizing data. Now this is where our modern computer technologies have come in.
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Slide: 00:14:37
A computer is a high speed idiot. It will do exactly what you tell it to do, very fast, without getting tired, and over and over, very accurately. Our biggest frustration is that it does what you tell it to do and not what you want it to do. But, recognizing that, what we have put together, and this is available free for download, and it runs on a PC like this one, is a computer program, called a Landscape Management System, that has over 40 C++ programs that inload stand level inventory data, some landscape information, and if you want to visualize on the landscape level, it also shows, you also would download some GIS
Slide: Input Data 00:15:30 information. Now the important thing here is that the stand inventory is standard inventory for each stand we download such information as its latitude, longitude, elevation, site index, number of acres and age and it has grown to become more sophisticated with adding such things as habitat types, et cetera, as I’ll show can be used to develop more sophisticated analyses as we find that they are appropriate.
Slide: http://lms.cfr.washington.ed 00:16:06
Now, the thing that’s also critical here is that we’re finding that these tools are becoming increasingly useful because the technology is becoming easier at the same time that the public skill in technology is increasing. Anybody who has a child program their remote on their television can appreciate this point right here.
Slide: 00:16:29 Slide: 00:16:31 (The following are real time computer screens as the speaker uses program live)
Now, what I’ll do real quickly is show you just a, let’s see, I have until what time? How much more time do I have? Okay, so I’ve got plenty of time. I’ll show you now, this is the actual Landscape Management System. (manipulates computer screen). What you’d have is a folder, a portfolio put up in it. Put up and set up, this is explained on our website. And then you would open whatever portfolio you wanted, and I’m just gonna use a kind of a generic example one. This one is 500, no about 900 acres, we can go up to as many as 50,000 acres. Each of these is a stand. And let’s look at this stand. First of all we can, behind this stand, is the inventory information. And what we can do is first, look at this stand and get an idea of what it looks like. This takes the inventory information, plugs it into a Forest Service Growth Model and gives us a visualization of the stand that year. If we wanted to see what happened, I’d already grown this stand out, a number of years, what it looked like in 2025, this will also do that. And I had done a treatment in the meantime, and I’ll show you the treatment. So first of all it will visualize stands. We have in the background here, growth models for, all the Forest Service Growth Models for the regions of the United States as well as the ORGANON models, for the Pacific Northwest. You can load whichever one you want. And use it, this is being used pretty much in all regions of the United States. We can also grow out stands forward, if I wanted to take this stand and grow
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it from 2030 to 2050, this is taking the inventory data as it looks in 2030 and putting it into the growth model and projecting it forward in 5 year increments up until 2050. Now we can see what the stand looks like in 2050. You see that the trees have gotten taller there. Now, we can also do treatments in this. Let me close some of these, just a minute. We can treat for example, this stand. And we can do a clear cut if we want to see what we mean by a clear cut, it means we’re leaving fifteen overstory trees. We can change that. We can see it from above, below, et cetera. The main use of all of this is we can then take the output data and not just look at it visually, but look at it in terms of tables. And these are tables that take that raw data and converted everything from habitat suitability indexes, to wind and fires risk indexes, to volumes. We can get how much of the landscape, how much of each stand is in each stand structure, et cetera. Now I’ll go back to my PowerPoint presentation to continue. We can also visualize on the landscape level. Now, back to the PowerPoint. This is just showing the same thing. We can enter the stands. We can, as I showed you, pull up whatever Growth Model is appropriate for our Region, these are Forest Growth Models. We can project stands different ways forward. We can treat the stands, changing anything from our regeneration to the number and species we want to leave, diameter distributions, et cetera. We can also, as I showed you, visualize the stands at different times. We can also get a whole variety of tables for example, this table which shows for a number of species what the habitat suitability indexes are. These tables immediately output to Excel spreadsheets. That then allow us to put together changes over time over the landscape. We’ve done it for everything, for even assessing the elk populations under different alternatives on the Olympic Peninsula. Now, the, we can also by the way, look at the landscape at different times from different positions, how it would look under different scenarios. And we can add, let me go back one, we can add roads, streams, we can color different stands different conditions. So we can get, we won’t, we don’t just say ‘I think this will work.’ We can say what is our best estimate or does this work or not and then part of the use of such projections is to start asking yourself what are the strengths and weaknesses of this. And to do sensitivity analyses and try to get an understanding.
Slide: The Data Can Be Summarized Visually Using SVS Embedded in LMS 00:22.42
We can also use it to scope an area, see what it looks like, delineate XXXX our riparian zones. And the strength is, we take that basic data and put different functions to it to get such things as visualizations and to get such things as habitat suitability indexes for different species.
Slide: Analyses of Inventory 00:22:50
For example, if this species needs something like four trees greater than 30 inches in diameter, of the pine species, and then less than 30% canopy closure, we could check out which stands would meet that category during which year. If high wind risk where stands with a height/diameter ratio above 80 or 90 and had a total height above 30 feet, then we could check out which stands are at high wind risk. If we had stands that are high fire danger with a certain amount of litter, or certain length of live crown from the ground, we can check out which stands are have high fire danger.
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Slide: The Changing Structures & Values Can Be Projected Over Time 00:23:43
So what we can do is project each stand over time. And from that inventory not only visualize that stand, but we can also then say for each period what’s the relative condition of that stand relative to various values, be it the Spotted Owl habitat, be it wind and fire safety, be it many others. We can add that up across a landscape to say how much total area do we have in high fire risk, in suitable habitat for elk, or suitable habitat for Spotted Owls, etc. It’s based on the best equations we get from wildlife biologists for owl habitat, from fire specialists for fire, etc.
Slide: Coarse Filter Biodiversity 00:24:30
We can project how much of each structure do we get over time. And each time we change the treatment, and grow it out, we get
Slide: These can be converted to Summary Values 00:24:41 a new idea of, what new may be, what, we played ‘what if’ statements. And what if we do this, what will be the effect? For those of you who do EIS type of analyses,
Slide: Summary Values can be used to Integrate over Time & Space 00:24:57 we can convert these to summary numbers that we can then put into a matrix format. And as I’ll show you we later explain what those numbers mean.
Slide: Example of a Decision Matrix 00:25:03 Slides then ‘page back’ four slides. Slide: The Changing Structures & Values Can Be Projected Over Time 00:25:10
Now at this point, I want to point out that we then begin saying that along riparian zones we can map out the stand areas along riparian zones. Use the inventory for that, plus the slope aspect, soil type, direction of the stream, etc. and can we, by working with the various riparian functions be able to estimate the effect of different stand structures on our different riparian functions. Now to do that, we, I did the thing I did with the rest of this work, I got a very good graduate student. So now when it comes to the significant parts of this
Slide: 00:25:58 that is, the technical parts, I’m going to turn it over to my graduate student, Jason Cross. I’ll come back at the very end.
00:26:18
Jason: Well, whatever our future riparian management strategies are going to be, they’re likely to be different than they were historically, 15 years ago on the peninsula.
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Slide: Introduction 00:26:34
And in modeling riparian zones, the State has its own set of guidelines as to what we need to do. And basically it’s based on some basal area. But if we’re thinking in terms of fish habitat, we need to know, what does that basal area have to do, what does it mean, say in terms of salmon recovery, in terms of spawning habitat. Slide: Introduction (NCASI) 00:26:59
So the National Council for Air and Stream Improvement had a technical bulletin last year. And they came out with six functions that they feel that riparian zones serve in terms of fish habitat. And it was mainly a large literature review of many, many research studies on all of these functions. And they divided it into shade production and temperature moderation of the water. Riparian zones are a source of large, woody debris, a source of particulate organic matter. They act as a streambank stabilizer. They serve to reduce sediment and as a filter for chemicals entering the water.
Slide: 00:27:38
So we can take our GIS data and we can take our landscape data and we can remove and isolate our riparian zones and begin to deal with those. And the inventory data. We’ll just be dealing with these specifically. And in terms of those six functions.
Slide: NCASI 00:27:56
The first one we started to look at, or I’m starting to look at and model, is shade production and temperature moderation.
Slide: Water Temperature Can Be Predicted 00:28:04
So, we know that water temperature can be predicted based on its speed, all sorts of factors. But they’re known and we can quantify them. And mainly we can, what we’re concerned with is not so much the characteristics of the water, but the characteristics of the trees around the water and how it influences it. So we have our heights, we have our inventory data. We know how high the trees are, what their species are, we have some inventory on their crown, crown ratio. What we can do is take that inventory data.
Slide: 00:28:38 from one of the tables from LMS, an output of LMS, created a spreadsheet that takes the inventory data, right in the middle of page one there. But it also takes into account many of the other factors that are going to influence stream temperature and shade which are on the left. We would want to know the width of the stream, we would want to know the angle of the stream is generally flowing, where the stream reach is flowing, the slope of the stream, the sideslopes on both sides, XXXX time of year, and the last one is for a different function. So we can take that data and then, using the crown ratios and all of the inventory data
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Slide: 00:29:26 come up with somewhat of a histogram by height of how much crown closure do we have at different levels. So where effectively, if the sun is shining through the crown, at what levels at what percent, what percent of the light is passing through the crown at whichever height and then is that going to hit the stream or not, based on an amalgamation of all the other factors. So we can see here that, this is a stand at our school’s experimental forest. Where we have 100% crown closure at 40, 50 and 60 feet. And then it tapers off as you go up.
Slide: BR Steeples 00:30:00
And what that, if we compare that to the actual, compare that to the stand, the stand is, the inventory data we projected on the left of the stand. Then we have on the upper right, we have the histogram, just a wire frame here on the bottom left. Well, this becomes important as you put a stream running to one side of that stand. You have the sun, going to be putting some radiation in, and we’re gonna wonder how much of that radiation is gonna make it right to the stream.
Slide: 00:30:26
Well, the path of the sun is also something we know. U.S. Naval Observatory seems to know a lot about it. So we can get some equations that model the path of the sun, given your time of year, your latitude and all of these things and what we can come up with
Slide: 00:30:45 is a graph based on all of the inventory data, channel morphology, topographic features, of when do we predict during the day, given this stand structure, that the sun will hit the stream at various percentages. 25% of the sunlight will be making it through first. It moves quickly up to 100%, stays there for a while, and then tapers off and then we’re in full shade again. What this allows us to do, is now we can take two scenarios. Say we can project the stand out for 80 years, see how this functions over the course of 80 years and then maybe under a ‘do nothing’ scenario. And then we can take another scenario that’s managed and see is that significantly different in terms of shade production. It will certainly alter the other five functions, but in terms of shade, we can start comparing different management scenarios in riparian zones.
Audience: Can I ask a question?
Speaker: Yeah.
Audience: Have you developed this enough, that you could look at that and say we don’t have enough sun from mountain alder on the streambank or if the potential is there, can you divide them up where you can have the amount of growth the mountain alder XXXX.
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Speaker: No, but I can, no. As far as not specifically that species. Any inventory, it’s, the whole, I mean everything is kind of premised on the ‘garbage in garbage out’, so however good inventory data I can get in, I can produce analogous…
Audience: Our inventory includes understory shrub, pretty much
Speaker: but that probably, in terms of the sun, in understory, will, for all the sensitivity on all the different stands we’ve ran, understory plays a very little, very small role in moderating temperature and actually effecting the amount of sunlight hitting the stream. As the sun tracks up through the sky, it passes through, passes through various stages of shade very quickly. It doesn’t spend a lot of time in the 25, 50 and 75. You don’t get a very big bell-shaped curve. It passes through, you’re in full sunlight, and then it starts to taper off.
Audience: Let me inject one more, if I can?
Speaker: Sure
Other Speaker: So far, nobody’s come up with a successful understory growth model. I’d love to see one, we’d put it in the minute we could get one. I guess the point is, what you could do for tree species is continuously plant them in the understory and the growth model would tell you whether they’ll survive or be killed. Based on how much overstory you have.
Audience: So I can interpret that towards shrubs?
Other Speaker: Yes. Sort of.
Audience: I just wondered, have you done any modeling with any data with photosynthetic available radiation?
Speaker: Not yet.
Speaker: Mainly, at this stage what we have right now, mainly just tracking for the major overstory. How much of the actual sunlight’s getting through. I haven’t moved into any of, maybe version 2.0.
Audience: Inaudible
Speaker: Yes. I’m looking at a 25 foot stream.
Audience: And what direction is it going?
Speaker: It is traveling southwest, no I’m sorry the stream output is 135, so that’s traveling southeast. Southeast. The time of year is zero, so its the Ides of March, it’s the
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Spring Equinox. And you’ll see this, this would, if I were to, as you change the time of year, that whole curve shifts, left and right, and back and forth as you widen the stream, the entire thing gets the entire amount of sunlight, gets wider, as you harvest the upperstory, or the overstory, the tallest trees, it will also get wider, ‘cause the sun will pass through and be up above the tallest trees earlier and stay above the tallest trees later. So it seems to turn out, as far as sensitivity on this, that management of trees is not the biggest player. There’s many other factors that effect temperature moderation. And shade production. Any other? Okay.
Slide: NCASI 00:35:28
The next one we’re going through that we’re just working on is large, woody debris recruitment.
Slide: 00:35:35
Which seems to be a popular topic. The old version of large woody debris, or management of large woody debris was take it out. It’s not the plan anymore.
Slide: 00:35:44
So what we need to know, is given our stand data, trees fall in a relative random pattern across the landscape, on the flat landscape. As you increase the slope, you weight how often it falls, progressively more and more downhill. But all of those factors can be expressed also and quantified. So on a flat landscape, on any soil type, a tree is going to fall relatively randomly. But we’re gonna bank on that and use that. Put another stream there and now we’re wondering how many of those are going to fall into the stream and help salmon out in providing habitat, creating pools and riffles and whatnot.
Slide: 00:36:25
So we certainly don’t have streams everywhere, we have many, we have different channel shapes and stream reaches that go around bends, and meander and wander. Some will be straight and some won’t.
Slide: 00:36:38
There have been some studies on exactly how to predict how a tree will fall and what’s the likelihood of it falling. We can calculate the effect of height, a minimum diameter that we need. We can take our inventory and run a taper equation to the top of whatever the minimum diameter is knowing that, knowing how far away from the stream it is once we know the dimensions of our riparian zone, we can start to talk about predictions involving how often a tree will hit.
Slide: 00:37:07
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Well, what we can also then, what I’ve done and, it, you certainly won’t be able to see it here, guessing at a distribution of trees and how there is a, pick any, any height tree you want, a 50 foot tree, a 75 foot tall tree to maybe a six inch top or a ten inch top or whatever minimum diameter you have, making an assumption that that 50 or 75 foot tree to a 10 inch top is likely to be anywhere in the stand, randomly distributed, it might be 50, it might be 10 feet from the stream, it might be 30 feet from the stream, and it might be 50 feet from the stream. And there’s really no weighting, it’s not more likely to be in any one place at the riparian zone or other. We can start to make some probability predictions. And so we’ve done that. If we can have an estimate of how many snags per unit, time per unit area, how many trees are likely to fall down, or become diseased, or just die off and get ready to fall, then we can begin to and that’s the crudest form is the very last number on the bottom left. I have, for this given structure, about 3% of the trees I’ve said will, are likely in this time period to become recruitable. They’re going to die off from some vehicle or another and fall. And I can use, make some probability models based on a uniform distribution of trees to give us predictions of how many pieces of large woody debris this stand structure will produce and it’s all based on heights of trees and diameters. It’s distance independent. It doesn’t matter where the trees are on the landscape. All that matters is how wide your riparian zone is and the distribution of trees and their heights. So we can come up with fairly accurate, at least accurate enough for the math department, to give it the okay. Models on tree falling. It can be weighted for stream slope or for a sideslope running into a stream, it can be altered for channel morphology, you can account for all the variation with the mathematical models.
Audience: Are you familiar with the XXXX?
Speaker: No.
Audience: Basically XXXX the same thing. (inaudible)
Speaker: Oh, yes, I’m sorry. I am.
Audience: One of the things they ran into and that XXXX conceptually on the one thing, is that XXXX models to XXXX models pressure mentality and as we’re learning more and more about what wood recruitment (inaudible) in fact it may not be the XXXX in a lot of places, (inaudible) they tried to crudely draw up XXXX to talk about wind throw and bank erosion and some of the other things that can effect wood or not XXXX streams. I’m just curious if you’re planning on or considering doing the same?
Speaker: Well I guess from a mathematical standpoint, a lot of those things we can weight probabilities based on those if a stream, once we’ve modeled some of the other functions, if a stream we know is likely to erode, or it’s gonna have sediment problems and gonna carve out the bank, then we can weight our wood debris model to take into account for that. Once we have better knowledge of the other functions and how it effects some of the, maybe the functions of the trees or the what it’s gonna effect the life span of the trees directly on the streambank. Small trees that are far away, I guess a possible drawback of my model is I, if I have a 50 foot tree, that’s a
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hundred feet away, I’m not going to consider that as being a possible candidate to somehow make it into the stream. There are probably vehicles that can do that, or there are methods that do that, but I’m considering only the trees that are in the riparian zone, that are, as they stand on the ground, tall enough at a certain minimum diameter to make it in, but knowing that I can weight it for, I can weight any area, or given other factors, such as carving out a bank or something.
Other Speaker: Let me add a couple things. Right now, XXXX mortality will come from the growth models. (inaudible) We also will eventually have it where you can fell trees into the stream and as we get into monitoring and find out that there’s a certain amount of XXXX mortality that we could say correlate with habitat types, or something else, then we would be able to add that factor. Right now we’re probably (inaudible) good points.
Audience: Things are running through my mind too. I wish I was back in college and 25. (laughter) This just blows me away how different forestry XXXX is now or whatever they call it compared to 32 years ago. But, how about chaos? You get a root rot pocket, I’m thinking of specific cases, you didn’t see all XXXX in that cross-section. There was more going on there than you saw. That was made good. But you had a root rot pocket up above that thing, several naturally, but eventually that stuff died and started falling in, started a chain reaction of events and all that wood came downstream above that cross-section. Actually had three channels at that cross- section. It was dechanneled because of the load of wood debris that came from insect and disease problems. How do you work that kind of thing into a model? Chaos?
Other Speaker: I’m glad you asked that. The first thing is, when we present this, we sometimes feel a little bit like Henry Ford did, knocked down the walls and space and pushed his car out and driven it around the block and somebody says ‘great, but does it have fuel injection?’ The way I foresee these being done is the continuous quality improvement approach. Which is what the Japanese use in automobiles and cameras. They came up with the best system, and then through monitoring they found out what’s the difference in reality between what they produced and what they thought they were producing. They determined the cause of that difference and corrected it. I’d see a manager who is using an area. They would first go with the basic model. Later if they know that this particular reach is full root rot pockets, they could adjust the model along that area. XXXX I think they’re gonna get enough natural recruitment here, this XXXX enough recruitment, what does that do for my XXXX areas. So you start with a base and then you continuously improve it with each XXXX update. So I think there’s a place for that, but I think we start with the simple points and then determine how important each of the others are.
Audience: Right now the model is kind of individual trees and…
Speaker: Actually, it’s, essentially, yeah, it’s taking into account given an inventory, I divide it into one foot height classes, count up all the trees that are in those height classes, there is a probability algorithm that probably isn’t worth deriving on a chalk board
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right now, but, that we’ve used that given a random distribution of trees across a landscape, is accurate, or is correct to use, to predict how the tree, what’s the likelihood of the tree hitting the stream. We can then account for curvature of the stream or any of the other factors. So it takes into account, the, at one foot height classes from top to bottom, all of the trees that are possible, then from all of those that are possible, you have to choose, and those are all of the live trees, you have to choose a certain amount of the live trees that are going to fall into a stream or fall down at one time, unless you have massive event, hurricane or something,. So then you have to decide either through a growth simulator or a snag modeler or something, given those candidate trees, how many of those are going to die off in a given time period and become your true candidates of falling, and then we have the prediction based on those trees. So if you’re weak link is maybe guessing how many trees are going to be recruited, then at least you know that that’s where you need to do improve a snag model or a prediction of how many trees in a given time period, and that will incorporate disease, likelihood of disease, fire, wind throw, all of, any of, somewhat more random and clustered events.
Audience: I didn’t bring this up to poke holes in it. I think it’s cool.
Speaker: Oh no. It’s gotta, you know, to get to 2.0 you gotta go through tearing down. Not tearing down, but question and answer. Audience: Have you run any modeling on decay XXXX?
Speaker: I haven’t put that in. I mean some of the stuff I’ve read, does talk about that. I mainly worried right now, I know that, the form of the wood as it enters the water is gonna be important but I haven’t…
Other Speaker: Actually, one thing I can say to this is that XXXX who’s doing the other computer programming XXXX trees die, or you can create snags. He has programmed in a decay table that decays it from one snag level to another, and a certain number of them fall over and then they go through decay classes. Now it’s not well calibrated yet, and you’d want to calibrate the local area, but this model, we call it a ‘gray box’ because this is where we want XXXX to fit in it, step in and calibrate the rate of decay to your local area. But what he’s building in, and I think within a month he’ll have it, the ability to go from dead trees, either naturally died or ones that XXXX, to snags of different decay classes to XXXX XXXX classes. And when they fall, is when Jason predicts whether they fall and hit the stream or not.
Slide: NCASI 00:48:12
For the next one, the one we’re working on, starting to work on currently is particulate organic matter. I don’t have any fancy slides for it. It’s based on a Forest Science monograph by Tim Mitchell, essentially the monograph is based on Douglas-fir. How every year, trees grow somewhat of a shallow foliage and there’s equations to describe the shape of it, but it somewhat thicker near the top and near the base of the crown it’s fairly narrow. Douglas-firs hold onto their needles a certain amount of years, in the study he was using it
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was five, so every year there’s an inside shell that’s going to slough off of trees of particulate organic matter needles and whatnot and hit the ground, so we’re trying to, that’s what we’re currently working on, going from inventory data and landscape data to somewhat estimate the amount of particulate organic matter that’s gonna slough out of the stand each year as the stand grows, the shell gets bigger for each tree. And then certainly having to go from Douglas-fir to other species. Red cedar, hemlock and everything else. So that’s kind of where, as far as, what I’m currently working on, is the particulate organic matter model to be added.
Audience: Can you model branches shutting as XXXX?
Speaker: Yes, that’s part of his, that’s included in some of his work.
Audience: How about the fall, the rate of fall XXXX?
Speaker: We’ll probably be able to look at that, but that’s also somewhat canceling I would say it’s a fairly random event. As a tree, as a branch decides to fall, or maybe it has another decision in it, (laughter), and it’s working it’s way to the ground where it lands is somewhat predicted on it’s spatial sideslope, it’s partners around it. So I would say, you could model that, but if you’re asking a mathematician, they’d say, they’d probably say that it’s going, it would cancel itself out over the course of the riparian zone. That one tree falling one way is going to be just as likely as having branches on other trees, every other tree falling, essentially in a uniform random pattern.
Other Speaker: Let me point out that Jason has degrees in both Forestry and Mathematics. And he’s engaged the Mathematics Department in this. So we literally get their input and blessing on this.
Audience: Jason, this model XXXX going there. (inaudible) specific, both in terms of the foliage shedding and the XXXX Douglas-fir (inaudible)
Speaker: Yes, so moving that to other species is the big step in possibly contacting Mr. Mitchell and asking him to do that for me.
Audience: I just wondered what your XXXX, you have certain perimeters that you’re ready to sequence out or?
Speaker: No, not yet. I’m just trying to model from inventory right now, I’m working on moving from inventory to, I mean from output tables of our LMS program, are we going to be able to accurately, we can grow the trees, we do know the dimensions of the trees, how can we just model this shell of foliage and how much is going to fall, and then we can, filter, on what makes, on what’s considered good and what’ considered not particulate organic matter or work on…is that you question?
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Audience: Well, I guess I meant more of a chemical level of looking at pomp, XXXX seed to XXXX ratios, looking at more of a chemistry, and I just wondered if that was?
Speaker: I would say that the sense of the model is more for, if we can model whatever it’s going to be seed and end ratios, and all of that, what we’re wondering is how well management activities maybe differ from a ‘no action’ scenario on the landscape, how will management activities significantly alter the amount that’s going to fall. And that may influence the total seed to end ratio, but some things we can hold somewhat constant or maybe not constant but we can, I guess account for, probably after a comparison, right now I’m working so I can just compare two landscape, two management scenarios and does the management significantly alter the amount of particulate organic matter, whatever its composition and makeup. Does is significantly alter that?
Other Speaker: Thanks for that, that’s an interesting point. What Jason is doing, is he is modeling within Excel spreadsheets. Once that gets down, we give it to our programmers who hardwire it into the computer code that will then just give us a line output of organic matter, or shade, time of day, etc. For each reach or stream. If XXXX ratio were important, this is where we need input from riparian ecologists, we could put a relationship between this foliage and branches and carbon/nitrogen ratio and be able to come up with those XXXX. That would be something that we’d be pleased to offer XXXX afterwards.
Speaker: If we know the, we certainly know the distributions of species, and then I’m sure it’s known what species have the particulate organic matter that’s gonna be produced by each species, we can know it’s chemical makeup and then have ideas of what that, so I think it’s all within grasp. But we’re not there, yet at least.
Other Speaker: But actually (inaudible)
Slide: NCASI 00:54:30
So then next one then, and these are now in the future. The next three to do are really the first three NCASI called source functions. These are things that all of the riparian zones add and contribute to the stream. The next three, streamline stabilization, sediment reduction and chemical removal are some of what they consider ‘sink functions’, things that they help take out and moderate out, you might not want too much of in the stream.
Slide: Areas of Geological Uplift 00:55:00
So, as far as streambank stabilization, Western Washington, kind of an area of geologic uplift, mountains are rising, the rivers are slowly carving down your valleys, and in between you’re getting steeper slopes,
Slide: Steep Hillslopes Fail at Predictable Angles 00:55:13
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and they’re ever-changing, those slopes if you have trees on them. And then you harvest the trees, or they’re harvested by a natural event for you. There’s a certain angle of repose. A stable angle that a sideslope can handle. And if you remove the vegetation that’s kind of glomming on to all the soil and stabilizing it, after a certain lag period, you’re gonna have a slump.
Slide: 00:55:37
So, we saw this slide earlier. So I don’t get the big wow effect.
Audience: It’s better. (laughter)
Slide: Wenatchee 00:55:45
After the fire, we’re gonna have these slopes that look like, that have been destabilized.
Slide: 00:55:52
And at a certain point, those slopes are going to slump and it’s not so much a matter of if, it’s just a matter of when. But if we can predict that, and if we can model these things accurately, we can start to manage for that. We’re not always going to be able to prevent it, but we can account for it in our management practices, and what we’re doing.
Audience: You’ve got snow there, so is that including precipitation, rain, snow packs, etc.?
Speaker: All of those things can be incorporated. These are all in the, I haven’t really touched on these. But these are where we’re going after particulate organic matter, we start to tackle these things. But are what we do know, a lot of these are, luckily, some relationships are out there. We don’t have to start from ground zero. We just are going to be incorporating them into our landscape and saying how do our management strategies alter them, or increase or decrease risk, or exposure to these events.
Slide: NCASI 00:56:52 Slide: 00:56:53
We have sediment reduction, we certainly can go out, and we have a lot of data on streams. Or if we don’t have it on a particular stream, we can get it, morphology, depth, what kind of makeup does the stream have.
Slide: Lane’s Relationship 00:57:05
Sediment traveling down a stream is somewhat, been quantified. There are relationships out there. Lane’s relationship, that have certain quantity of water moving at a certain speed will carry a certain amount of sediment, and if it doesn’t have it, it will find it. And it does that by carving out streambanks and eroding the sides.
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Slide: Without bedload, water will accelerate until it can pick up bedload downstream 00:57:30
So if you have a river with an upstream bedload, it kind of will deposit it as it moves down. If you don’t have one, if you don’t have your, any upstream bedload, it’s going to undercut in the yellow zones to get that amount of sediment and then deposit it finally as it slows down at the mouth.
Slide: In very large bedloads, water will create a braided channel 00:57:53
There are certainly characteristics that you want and that you don’t want. Rivers with a nice bedload where you can, you’d probably want to avoid a real braided stream channels type. I’m not a stream person yet, but I will be soon.
Audience: I’m (inaudible) and I suppose I should before I make this comment. But my gut thought was that when they say, you know, they talk about sinks, and they talk about sediment, that I would think that they’re talking about all that work that XXXX Megahan did, where he talks about sediment coming off the hill and it hits the buffer and it filters through the grasses and it doesn’t make it to the creek rather than sediment transport in the stream type question.
Speaker: Well that’s certainly, we don’t know, for any given landscape I think we could probably assume we’re going to be considering management strategies for both ones upstream and downstream and how much sediment if we’re upstream actually makes it to there will actually effect the entire, I think effect the system. So, I think you’re right that it is, that’s what we would want to be talking about, or what the NCASI is discussing, and what the articles in the NCASI are discussing. But it’s still a function of delivery to a stream, and then what happens from there on out.
Audience: Good luck with this, because I’ve been trying to get geomorphs to do this for me for years. Can’t do it yet.
Speaker: Hope I didn’t make a deal with the devil.
Other Speaker: What they always say on (inaudible)
Audience: If they can do it, I’d be just delighted, we need it.
Slide: Bedload sediment amount and flow rate can be managed 00:59:54
So, bedload sediment, we can manage these things, through large wood, projecting our large woody debris and modeling that, how much is going to fall and if not enough is going to fall, maybe we need to go out there and fall some ourselves. We can predict, or we can know, or knowing, being able to manage for the time of slope failures, knowing when they happen, we can incorporate that into our management plans and estimate what the lag period is and
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what’s going to happen based on what we know on our landscapes. So if events happen upstream, either managed or unmanaged, we’ll be able to have an idea of what we need to do in the future, given the current conditions, given the landscape information. So we’ll be able to hopefully model these things, and accurately account for it.
Slide: Bedload sediment moves at predictable rates 01:00:42
Certainly, knowing, we’ll be able to, again, your channel morphology, and everything about it is a function of all of the landscape and inventory information and all of these other factors. If we know those, we can predict the water volume’s gonna be set for us. How fast it’s moving will be a function that we might not have as much to do about it as far as slope down hill. But certainly we can moderate it with large woody debris and other factors that we can incorporate into our management plans.
Slide: NCASI 01:01:16
And the last one is chemical removal. I don’t believe I have a slide for that because that’s about a year away. So I haven’t quite got to that but certainly the function of the riparian vegetation is a filter. And knowing how our management activities are going to effect the ability of it to filter out chemicals from entering the stream or the quantity that do. So, basically it’s relying on the fact that we can go out and quantify a lot of these things. A lot of the factors that are going to effect it are, we can quantify and incorporate into a model given we’ll know where our weak links are. So that’s probably the most important part of it, is identifying the weakest link and hopefully working on that the most. But if we can get good solid relationships that we’re confident of then it’s a matter of either having the best possible information to put in, in order to get the most reliable predictions out. That’s basically what I’m working on. Did you want to finish up?
Change of Speakers (back to original presenter) 01:02:35
Slide: The decision-maker chooses an alternative 01:02:50
As you can see, what we’ll end up with is with as series of different objectives down here and we can several of them for riparian habitat, or one of them, as we start pulling these relationships together. You can look at different alternatives and how it effects each relationship.
Slide: Two Step Process 01:03:11
For example, if someone were interested in this alternative, let’s see (adjusting computer screens). Okay, if someone is interested in this alternative, then we have a way of going into the field and going through a two step process
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Slide: The chosen alternative had these pathway proportions for this group 01:03:45 to come up with
Slide: Then the field forester determines which stands follows each pathway 01:03:47 a final result.
Slide: Using this process, a very detailed inventory is not needed before the analysis process is done 01:03:50 and this is tied to the field forester. Slide: Target landscape proportions are matched with suitable stands 01:03:51 Series of slides are then shown in 1 second frames
Slide: Activities and opportunities 01:03:54
I won’t go into the details of this, but the result is that to get the objectives that you want, this riparian habitat, et cetera, then over the five or ten year planning period, you end up knowing exactly which stands you’re going to enter, what your operations are going to be and what you’re expected outputs are. And during that five year period then, you work with a certain level of confidence that this will be the best understanding of what results we’ll get. You would of course not be entering every part of your landscape at all the times. We call this a portfolio management approach because by keeping a large amount of information, it allows you not to create a uniform product, but to be able to play the markets with a series of different products and objectives across the landscape. Then the result
Slide: The results are monitored as described earlier 01:04:52 of that is, we test this three ways. Whenever we put any of these relationships together and predict the outputs, the first test is what we call the laugh test. Does this make sense? And if it passes that, then we do sensitivity analysis. What if we vary the rate of large woody debris five percent, what effect does that have? What if we vary the growth model five percent, what does that have? If the rate of woody debris recruitment varies the riparian functionings by thirty percent, with the growth model, varying it five percent, varies the riparian functions by two percent, we need to, we know we need to put more emphasis on woody debris recruitment. Then at the end of our planning period, we can go out and do a hundred percent visual monitoring. This is what we expected, this is what we got. We can stratify the stands into a good fit, medium fit, poor fit.
Slide: Monitoring 01:05:56
Sample at different intensities with the actual data there. And looking at the expected and the observed, this is the difference. Determine the biggest cause of that difference. Was it because our inventory was bad? Was our growth model bad? Was our relationship for example between woody debris recruitment expected an actual, was that the bad thing? Was
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it that our foresters didn’t follow the plan? Whatever the error was correct that and then move on
Slide: A predictable diversity of values are provided 01:06:29 so that you, so that you, it constantly increase the precision in the accuracy of this. And by using this model we can predict a number of different values at one time rather than just focusing on one of them.
Slide: The information can be made available to the public 01:06:45
Now for public lands, we’re encouraging that if you have a plan, put the landscape or stand visualizations expected up on the website. Because if you’re not achieving what you’re expected, then you as a manager want to know more than anybody else.
Slide: Mohr’s Law 01:07:04
This is just a quote I love. We overestimate the impact of technology in 2 years and underestimate it in 10 years.
Slide: Two predictions of information technology 01:07:12
There’s been two predictions about technology. One is, it would form top-down planning. Another is, it would eliminate middle level management. And both of them proved to be wrong.
Slide: An emerging pattern: how can we make use of it? 01:07:25
What we’re finding is that information technology is going from this level up. We see where large companies and even factories are upgrading from mainframes to PC’s.
Slide: Other Emerging Technologies 01:07:37
The program that we have is one of many emerging technologies here.
Slide: 01:07:42
This is just another emerging technology that, a digital view of an increment core of a tropical tree. The computer can not only spot the annual rings, but can count them. Whereas before we didn’t even know that this species had annual rings.
Slide: http://lms.cfr.washington.edu 01:07:59
This is more information. You can download both the model, by the way, the riparian functioning is not in there, in this version. It will probably be a little ways away. But it also gives you a tutorial and we’re putting on short courses on using this, both through our rural
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technology initiative, that’s for consultants, small land owners, Native American groups, etc. and we’re putting on other courses as well, through our CE department. This is all, I think I’m going to do something that I’ve been wanting to do for a long time. Let me copy this to the next page, because, (manipulates data on screen) this is what I think people…okay..
Slide: Computer needs for LMS2.0+ 01:09:28
Then, that’s it if there are any questions. We’d be glad to answer. Okay. Domoni: I think that’s it (applause) It is now 2:25, why don’t we take a 15 minute break…. Tape 4 00:00:00 00:00:11
Speaker: Charles Chesney
Today I’d like to get some information from you. It’s a game I call ‘Wood Work.’ It’s a thinking exercise. I apologize for those of you who have done this before, you can ignore it. But by way of introduction, my name is Charles Chesney. I work with DNR in the Forest Practices Division. I work in Yakima and my beat is Eastern Washington. I’ll share with you some results from initial project work for a long term measurement project or a monitoring project in what I found out today, thanks to Bud, is a strong maritime, or mostly inland maritime forest settings. Looking at the effects of wood of all sizes in small steep streams. I use this thinking exercise really as a way to start a presentation with an ice breaker, it’s also a way for me to get you thinking about what some of us or many of us here might think of as being hot button issues. And those issues can be translated into questions, L1, L2 questions. Or project objectives for a variety of reasons, but I’d like to collect some information from you, and they can be based on your field experience, your modeling experience, guesses, hunches, professional judgment, personal judgment, whatever. I’d like to get responses from you for these three questions: how many riparian trees fall down, whole or in pieces, and you can express that as trees per unit area, trees per acre, per year, some time frame, whatever. Of the trees that fall down, or lean, what proportion or what percentage have any portion that lay over the channel? I think you’re beginning to see what I’m getting at. And of that percentage, of question number two, of the fallen or leaning trees over the channel, what percentage becomes wood in zones one and two? The zone concept is described on the back side in the cartoon in what I would call hydraulically active or habitactically active wood. Habitactically is a word that I made up so don’t, you can blame me for it. But there had to be a parent to hydraulically active wood. So I’m gonna someone from the audience, to at least give me something to take home with me. And for those of you who give me responses today. Some of you may be uncomfortable doing that, or may not care, that’s okay. For those of you who give me data today you will get a document set I brought about sixty pounds of paper, from Olympia. This is a document set, that maybe has about six or eight documents, they’re each little snapshots, and the content is descriptions of standard methods for doing long term measurements, for doing monitoring. So the topics include such arcane things as doing reference point surveys, doing aquatic habitat surveys,
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doing stream temperature surveys, salmon spawning gravel composition, etc., etc., etc. So as you can see I have several sets here and I’d like to ask one of you from the audience to at least give me some numbers to take home with me. How about Bud, got any numbers for me?
Audience: What was it Johnny Carson used to do? (holds envelope up to forehead)
Speaker: Hit him with the cue card….(laughter)
Audience: No, he’d put the envelope on his head…
Speaker: Oh, okay.
Audience: (inaudible)
Speaker: Divine it.
Audience: (inaudible) Funk and Wagnall’s back porch. How many riparian trees fall down? Well. Unless it’s a high leaf system, all of them fall eventually down.
Speaker: Okay. So how would you express that on a per acre, per…
Audience: Well, 100% eventually fall down.
Speaker: Okay, I can see I’m gonna have trouble with you (laughs)…so let’s look at a plant association group. How about Ponderosa Pine/Douglas-fir in the Ochako Mountains of Oregon. Audience: Yes, okay.
Speaker: What percentage of those trees fall down whole or in pieces over a century?
Audience: Over a century?
Speaker: Yes, over a millennium, I know you’re a big thinker.
Audience: They still all eventually fall down.
Speaker: Okay, okay. One hundred percent, that’s a response. Moving on to question number two: of the percentage of trees that fall or lean, what percentage have any portion that lay over the channel?
Audience: Could I stay within one tree hide?
Speaker: You can do anything you want, I’m just trying to get people to think about this. Go ahead.
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Audience: (inaudible) height of the bank…
Speaker: This is a directional question.
Audience: Ten percent.
Speaker: Okay, good, very good. So you can express it as a percentage. And the third and last question is of the trees that fall over towards the channel, what percentage becomes wood, that is immediately becomes wood that is located, turn it over and look at the cartoon, becomes hydraulically, or habitactically active.
Audience: Immediately?
Speaker: Yes, immediately. Like right away.
Audience: Is it an A channel or a C channel?
Speaker: I want your data sheet. Any channel you want. You can qualify this in as many hierarchies as you want, just give me a number.
Audience: If it’s an A channel, quite often there’s straddling, and they have no impact right away. Maybe ten percent again.
Speaker: Ten percent? Good.
Audience: (inaudible) tips going in. If it’s a C channel, splash. A big one, anyway.
Speaker: So more than that percent. So you can see the kind of information I’d like to get from this. Thank you Bud. I will give you a document set. That’s all that’s required. It’s really pretty painless.
Audience: I want to (inaudible) across the stream, running above the stream have no effect.
Audience: Well, I interpreted his question to mean the water.
Speaker: Below the elevation of the bank top. So that’s zone, one and two.
I don’t want to belabor this, but I want this to be a fun thinking exercise for you. I am quite serious about this. If you give me data today, you get document sets. I’ve hoisted about sixty pounds of them from Yakima today and I don’t want to take them back with me. My purpose for doing this, you’re asking why is this nut doing this, my purpose in doing this is to challenge assumptions. And create a database of assumptions about tree behavior. There are three elements to this which way they fall, what’s the rate of fall and what’ the rate of immediate zone one and two wood production. So that’s it. I have no ulterior motive. I’m tracking assumptions and knowledge over time. Question?
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Audience. No, I just want a set of those books.
Speaker: Okay, well what you need to do is give me some data. If you want feedback on this, like a set of the data, I have an email address. If you stick it in the slot, how’s that, pretty easy, just stick it in the slot and I’ll give you a dataset.
Okay, guess it’s time to start now. Could someone tell me what this is? (points to screen) Audience: Gauging station?
Speaker: Okay. Where? (laughter)
Audience: I think it’s on Andrews Creek.
That’s very good. I took this on a, I accompanied a hydraulic firm doing copeland from the USGS from Pasco on its gauging missions on the Yakima River and this is the cableway where the Yakima River and milepost 18 near (inaudible) Creek. If any of you drive the Canyon Road near milepost 18, this is just downstream of that 150 foot tall right bank Ponderosa Pine that fell down? It created some hydraulic problems for the gauging station, but that’s the way the tree falls. So, good job. Okay, let’s begin.
Slide: Functions of Wood in Small, Steep Streams in Eastern Washington 00:08:27
So this is the title, functions of wood in small, steep streams in Eastern Washington. I also brought a poster along that describes this in greater detail. Should you need to reach me, I have business cards
Slide: Channel Reference Site Network Wood in Small Streams Project 00:08:42 or an email address that you can write me at. I’ve alternately titled this talk the Channel Reference Site Network and the Wood in Small Streams Project because its a little easier to handle. And I’m sort of an acronym hound and the acronyms for this are CRSN and WISSP, and I’ll explain that later.
Slide: Thanks 00:09:04
Though I’m the person up here presenting these initial findings, I’m sort of at the top of the pyramid and there have been lots of folks who helped me in a lot of ways to make this happen. Folks like Russel Langshaw, and Angel Spell, Susan Hattrup, many of these volunteers, but some not volunteers. (inaudible) very big help, Charlie McKinney’s here, helped with this project. Anyone else in the audience? No, just a lot of people who helped me with the project.
Slide: More Thanks 00:09:37
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And even more thanks to my supervisor, Nancy Sturhan, who several years ago, sort of let me hang myself with this project and hopefully hasn’t let me hang me out to dry, but given me the latitude in my job description within an organization to pursue something that’s rather far out. It is very monitoring-oriented. Dave Schuett-Hames was the editor who bled a lot on many drafts of my report. Doug Rushton and Helen Bresler also gave me some feedback. And Jim Matthews and Joe Wernex helped with the site advice and surveying equipment. Just so you know what’s in the background of these scenes, overlaying text…
Slide: Example of Background Images 00:10:27
…background images, sort of my theme for this presentation is to get you away from the L- word, (whispers: Large Woody Debris), get you thinking about wood of all sizes. And the L- product is not the story about obstructions and carbon and XXXX functions in small, steep stream channels. There’s a mixture of big wood and small wood and rock and soil that are, that create structures in small, steep stream channels. So what we’ll see behind a text are images that have been manipulated that come from the steps from a particular channel in Kettle Creek. Kettle Creek is a right bank tributary of the American River. It’s in a stand that’s clearly a west side maritime, strongly maritime stand of Western Hemlock and Western Red Cedar. Very unusual for the east side but not that uncommon.
Slide: Overview 00:11:33
Just as an overview then. What’s the project about? It’s a long term monitoring asset. At this point in the network, eighteen long term measurement sites have been created or established. The purpose of it is to allow for baseline and validation monitoring. At this point it includes a mixture of unmanaged and managed sites. And I would just argue that, very strongly, that unmanaged sites, are managed. They have their own particular disturbance regime. They just don’t’ have the disturbance regime disturbance associated with forest practices or urban practices or ag practices. They have their own unique disturbance regime. So the dataset right now for eighteen sites includes detailed measurements on over 5800 trees, over 2000 small pieces of wood were measured in great and gory detail about 400 other pieces were measured and 300 sediment obstructions.
Audience: This is all in Kettle Creek?
Speaker: Pardon me?
Audience: This is all in Kettle Creek?
Speaker: No, this is for the eighteen sites. Now if we had this much, these stats for one channel, I’d probably be measuring ten miles XXXX, but this represents the entire dataset.
For those of you who have done measurements, you may be wondering, ‘how did you measure small wood?’. Right now, there are no measurement techniques for measuring
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small wood, because no one has thought of it for some reason. I think of myself as a wood heretic because I tend to look at the small stuff, but I want to warn you, that if you do look at the small stuff, it’s expensive because, as you can see, the amount of effort put into the small wood is quite grand on the scheme of the measurement set. So just be aware, if you want to go small and try to understand small streams, you may be measuring quite a bit of wood.
Slide: Overview: Why 00:13:35
Why, the overview? Why was this done? This project was initiated by the Ahtanum Watershed Analysis which is an investigation process which looks at the cumulative effects of various land use practices, mostly forestry, on public resources. It was also designed to improve proposed management actions. It was also designed to validate a lot of assumptions about the way things behave. Challenging what we think happens and actually measuring it over time and trying to make sense of it. And of course the project was driven by two monitoring objectives.
Slide: Overview: When 00:14:09
When was the work done? The initial data was collected over a three year period. In ’97, ’98 and ’99. There’s a problem associated with spreading data collection over a period of years and that makes it messy to generate our rates of wood import, wood input and export, so in the year 2000, in August 2000, during that really awful fire season we had, I was fortunate enough to be able to make my trips in and out of the Ahtanum , Kewichi, Taitin and American Basins, and take care of business. Do all the repeat measurements, reestablish monuments, surveying markers, etc., etc., and things turned out pretty well. So this presentation does not include rates of change, like wood movement, tree fall, getting at the three burning questions I posed to you earlier, I’d be happy to present that at perhaps the next or the next beyond that or the next beyond that earthside meeting. Currently there are seven CRSN sites. CRSN means that Channel Reference Site Network. These are the unmanaged sites, and I already told you about my thoughts about unmanaged sites, but, and eleven WISSP sites, with a variety of different management prescriptions. The idea is to take repeat measurement data at about 5 year intervals or on an event-triggered basis, such as doing it right after a major flushing event, like the Pineapple Express of February ‘96. And the idea is to complete this over the long term, 300 years, like the construction of the Milan Cathedral, or at least 200 years, like the construction of the Tower of Pisa in Italy.
Slide: Overview: Where 00:16:01
And I know some of you are already rolling your eyeballs, deep in your sockets, man we don’t have time, we really don’t have time, but over the long term, we will see the value of this. That also poses the question of recruitment and recruiting talent to make this happen in 2150 and 2250 and beyond. And so that’s the whole other area of discussion. But succession planning is important, not only for trees. Where are the sites? They’re scattered around, sites in what Bud referred to as strongly maritime or inland maritime with some continental plant association groups or climates in the Ahtenum, Koenichi, Taichi, American Basins. This is near Yakima, okay. East slope of the Cascades. They include managed and
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unmanaged sites. This is a list of criteria for the sites. And I continue to look for sites. And actually there are a lot of people who continue to look for sites (aside: that’s actually not going to work very well is it) The sites’ characteristics include (aside: no, let’s do this) The site characteristics include confined channels that are steep, a drain, a small basin area, the channels are also quite narrow, less than about fifteen feet in bed, full width. The beds are alluvial not colluvial, they’re derived by the action of flowing water. They have wood, but they’re not bedrock controlled. One of the more expensive elements of CRSN and WISSP is the cost of rejection. I’ve experienced about a 95% rejection rate to actually connect with candidates that meet these, this list of criteria. And so for those of you who are considering doing this, one way to cut the reconnaissance cost is to invest in some volunteer, outdoorsy, adventure types who will seek out your sites, do reconnaissance missions for you and actually tell you what they found. Of course if you have access to a bell jet pack or a transporter beam, or a helicopter for a day, you can really cover a lot of ground. It was expensive to locate the sites, so be aware of that if you’re attempting to pursue this.
Slide: Overview: How 00:18:41
How is the work done, what are the measurements? The idea is to create permanent plots, through a random stratified sampling. By stratified sampling, there were a list of stream channels that came about from the Ahtanum Watershed Analysis that were chosen as the channel types. They were mentioned earlier in this list. That were subject to investigation, so those were the sample of all the channels out there we measured, the riparian plots were installed. They were not 110 feet wide, not 66 feet wide, not 50 feet wide, they were 75 feet wide on each side, which comes out to be a half an acre total riparian plot. The stream channel plot lengths are about 20 channel lengths in width, 40 to 55 meters in length. A bunch of tools were used to cut costs and increase the reliability of the data.
Slide: Monitoring Questions 00:19:49
So to the racehorse blinders, let’s get focused. How much riparian vegetation is needed for adequate wood input to the channel? These ear the two questions that focused my efforts. And how much functional in-channel wood is needed to retain sediment? So this is definitely a physically-based monitoring project.
Slide: Results 00:20:11
And so to the results.
Slide: Results 00:20:15
And the results are described here as a comparison between what was found in managed sites and what was found in the unmanaged sites. In the unmanaged sites, as you could imagine, the stem count, actually that should be trees per hector, trees per hector, four size classes were elaborately measured. Less than 3 inches, 3 to 9 inches, 9 to 20 inches and greater than 20 inches in diameter. More trees in unmanaged sites. Doesn’t, shouldn’t surprise you.
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Slide: Results: Channel Wood 00:20:58
In the unmanaged sites, the mean wood volumes were generally higher, though similar in the zone 2 component. I came up with some indexes that I want to track over time. Some, a ratio can also be developed to look at hydraulically active wood, zone 1 and 2 wood, is within the bank full perimeter of the channel. Zone 3 and 4 wood may or may not have potential to crack or fall into the channel. There’s a terrestrial component to the zone 3 and 4 wood.
Slide: Results: Sediment and Steps 00:21:36
I spent a lot of effort in taking detailed measurements of sediment and steps. Some of you may ask what were your criteria for classifying something. A step, like these steps here in this room. The criteria came from the work of Walt Megahan from 1982, or earlier. There are three criteria that had to be met for a step or a wedge or an obstruction to be considered and classified and measured. It had to have a minimum height of 20 centimeters, a minimum width of 30 centimeters, and a minimal length of 60 centimeters. So the 20, 30, 60 rule was applied to all 300 of these steps or obstructions. In unmanaged sites there were a higher wedge sediment find, one and half times greater. More steps, more steps as well. More steps trapping more sediment.
Slide: Results: Step Drop 00:22:48
Makes sense. On the unmanaged sites, the mean of step to bed drop was slightly higher, but not significantly so. For all the sites, that means pooling the eleven managed sites, and the 7 unmanaged sites, five of the sites, five of the seventeen, have a step to bed drop exceeding 100%. That indicates a lot of complexity. There’s a lot of energy and energy dissipation that occurs in association with the steps. And five, another five sites, had a step to bed drop exceeding 85%. So ten of the seventeen sites had step to bed drops that exceeded 85%. I don’t have a lot of other projects to compare this data to. There’s work by Douglas in New Hampshire, and elsewhere. So I want to develop more meaningful comparisons than just to within sites in this dataset of 18 sites. But by far the largest portion of the step drop is due to a mixture of materials, and including rock, wood, and in some cases soil.
Slide: Results: Step Construction 00:24:09
I paid attention to the actual building materials that created the obstructions or the steps. I was also interested in partitioning out the amount of drop, that means the bed drop due to small woody debris versus large woody debris. Wood drop in unmanaged sites 1.6 times greater due to small wood and 30% greater with steps that are constructed of large woody debris. Piece numbers higher, number of wood steps, of 100% wood steps, about twice greater. In the managed sites, we’re seeing a shift to the importance of rock, by rock I mean cobbles, boulders, sediments, grains and in this case, mostly well, Andosite and Basalt for these geologies. Don’t have a lot of variety in the geologies of the basins. So rock faces became the dominant type of material that created this longitudinal stair step pattern.
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Slide: Recommendations 00:25:19
So, as far as recommendations go,
Slide: Recommendations: Riparian Forest Structures 00:25:23
I’m making some recommendations for a riparian forest structure. But for a very particular riparian forest structure. And these recommendations pertain to creating conditions for a self-sustaining wood supply. This is to create conditions for a self-sustaining wood supply. So if you do a wood budget, that means that input equals output. So wood that has floated out, or decays over time is replaced by wood that comes in from terrestrial sources or floats in from places up valley. I will be giving you some information to take home that allows you to ponder this or consider it. Using a one to two to four to eight ratio these four size classes, you can see the numbers here are high and quite higher than…
Slide: Recommendations: Channel Wood 00:26:23
…than would be mentioned in Forest Practice Rules or targets for stand conditions to create in-channel wood for Eastern Washington. I also came up with some recommendations for total wood volume and also partitioning out the wood in the four strata. A point that I want you to understand here is my reason in spending a lot of time in describing the location of the wood is I’m testing a hypothesis about the importance of zonation. And what the hydraulic, at least, I’m not doing amphibian studies, I’m not doing aquatic studies, it’s totally a physical, physical elements of the stream channel in terms of sediment retention that I’m focusing on here. I’m very interested to know how long zone 1 and 2 wood lasts and what the role of zone 3 and 4 wood is, that is over-channel or near channel wood has, and how long it takes for zone 3 and 4 wood to become hydraulically active.
Slide: Recommendations: Step Quality 00:27:37
And some other rather arcane recommendations for step quality. This may be more appropriate to restoration…
Slide: Take Home Message 00:27:44
…types or trying to rebuild channels for some reason. And actually this will be a presentation I will be giving at an upcoming restoration conference in Bellevue. And if you do come to that presentation, the focus will be entirely on design criteria for rebuilding streams. So if you want to see me really go out on a limb, I’ll see you in Bellevue. Because it’s (passes out papers) rather speculative at this point. (aside: pass those around) So here is the take home message. And I designed this for you to actually take home, so I encourage you to do so. The take home message. I like to break these down into do’s and don’ts. Keep it simple. The do’s are, I really implore you to start making sense, measure small wood. If you are looking at small, steep stream channels, which in most channel networks, can comprise 60 to 90 percent of the channel network length. The fingertip channels. There’s a tremendous length in channel networks are in these small channels. They may not
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necessarily be steep, like in the Kitsap Peninsula, when you’re on a broad plain, you don’t have a lot of steep channels, but in steep mountainous terrain in Eastern Washington, the small steep streams make up a large part of the channel network. Start making sense, and measure the small wood. I gave you some brief stats here based on 2079 small wood pieces, 400 large wood pieces and 300 wedges. You can see that the amount of wood data that I collected is highly skewed towards the small wood. I am not going to get into the extreme detail, step construction or case studies. It’s really fascinating, there are 300 steps that we could talk about, it will be an interesting modeling exercise to make sense of the wood data but small wood as a building material, very important for our, for creating these vertical risers on steps. I would also encourage you to add data value by classifying the wood into four zones. You may want to simplify that and just create zones 1 and 2 and 3 and 4. I would also encourage you to pay attention to branches. That’s why I was drilling Jason earlier about the capability of models to look at branch rain. The raining of branches, the shedding of branches due to senescence of mortality and other mechanisms, tree fall, whatever. But in my measurement of these over 2000 pieces of small wood, a lot of the material was wholly or partly due to branches. So branches are a major source of small woody debris. That creates a bit of a quandary, because if we’re managing stream side forest vegetation for rapid growth, to create large wood, for whatever large wood is supposed to do, or maybe create crown quickly to shade the channel, for whatever objective, I would argue that by having crowns that are shaded as highly as they might be in a dense forest stand, or forests that we call overstocked, or stagnant, we’re not creating a crop of branches that are likely to fall into the channel. So there are trade-offs associated with creating these monster channels that put out a lot of annual increment. There are trade-offs of course. And I would encourage you to monitor, by that I mean do repeat measurements over space and time to evaluate the effect of wood, physical, and biological processes in the channel. By all means, stop data smog XXXX now. I would encourage you to stop piece counts because they don’t add a lot of value. They don’t tell you a lot about the placement of the wood. There’s a lot of hidden or assumed, there’s a lot of hidden information or assumptions made from piece counts. And so I would argue that if I were to give a hundred cubic feet of dimensional lumber to three awful carpenters, and I asked them to create some kind of shed or structure and they had an hour or so to do it, the intelligent carpenter would probably work on creating some structurally sound members by joining a couple 2 by 4’s to make a header, for a window opening. What I’m getting into is construction styles for building a frame house for instance. Piece counts won’t give you, it’s the design and the arrangement and the array of the materials that add value and strength to the individual members. So piece counts hide that whereas more detailed information, though it comes at a cost, will allow you to derive more habitat and hydraulic value, particularly as it relates to sediment retention. And above all, don’t forget, we don’t know what tree fall rates are, though some people have assured me that they know what tree fall rates are. We don’t know what the tree fall rates over channels are. And the particularly troublesome area for me is we don’t know what the conversion rate is of fallen wood into zone 1, zone 2, zone 3, zone 4 wood. I would argue that the production of zone 3 and 4 wood is just as important as the production of zone 1 and 2 wood. Zone 1 and 2 wood is, we just say it’s effective now. What happens after breakage due to floods? Debris torrents are not really common in the, on the Eastside, but they do occur, debris floats in the big torrents, just by decay, one to two percent per year of wood decays. What happens to that wood, it needs to be replaced. So the zone 3 and 4 wood is a over-channel or a near
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channel wood source that depending on it’s size, is likely to crack and break and fall in the channel. Someone has told me that, well what happens if we have a 5 foot diameter Douglas-fir that’s bridging the channel. It’s unlikely in perhaps three to five hundred years, that it’s gonna become hydraulically active. So it will decay or rot in place. There may not be any hydraulic or habitat value due to that piece size.
Slide: Three Burning Questions 00:35:11
So back to the three burning questions. I did give you a handout. I would like to get some feedback from you. I’m reluctant to call it data, but something that records your assumptions or hunches on rates of tree fall, rates of tree fall toward channels, and some stab at a conversion rate into hydraulically or habitactically effective swarns.
Slide: That’s It 00:35:42
I believe that’s it. That’s it. Questions? (applause) I believe we have time.
Audience: Charles, you’re, basically what you’re saying is, this is what I hear you saying, okay. That where in particular streams, the small, steep streams, you’re advocating having a bunch of little trees that self-prune and so forth, and have mortality and get into the stream, that’s a better sediment storage tool than what the current prescriptions are (inaudible) point of large streams (inaudible) is that what I’m…?
Speaker: I’m suggesting that we manage stream side vegetation for a diverse structure. And a number of size classes that will, they’ll live and grow and die and senesce and create small wood for the channel.
Audience: And your suggesting that we wouldn’t get that whit the current prescriptions?
Speaker: I’m suggesting that. Correct. If, it depends on what the landowner chooses to do with respect to management options. I mean there are a lot, a lot of things you can do with stands to go from a savanna to an open, to a desired complex stand. There are many pathways.
Audience: I guess where I’m having trouble connecting them is that this the descriptions have what I guess what I guess what we’re talking about mostly would be the perennial non-fish bearing streams probably. You’re still required to leave a heavy enough basal area that you know you can expect to get a lot of regeneration, probably more than we would traditionally want. And in practical terms, there’s going to be very limited manipulation other than occasional distractions, like every couple of years probably. So I’m having trouble seeing how we can change prescriptions to necessarily make things happen that way. We don’t have enough latitude.
Speaker: In some situations we don’t. And particularly in situations where vegetation is naturally sparse. One of the things that I neglected to mention here that in some of these sites, some of the sites landed on the ground where the layout occurred for the
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sites, where there were naturally bare Basalt Tallis slopes on west-facing and south- facing slopes in these landscapes there are regular to frequently occurring areas that are just barren, Basalt Tallis slopes. Trees will grow there very slowly, if at all, and those are sites particularly in lower, hotter, drier sites, Ponderosa Pine/Douglas-fir sites, that are likely to, naturally have had, much lower wood volumes. This dataset represents a particular set of forest types. I’ll just call them cool, moist forest types in Grand Fir and Pacific silver fir, mostly. Poorly represented are forest data from low, low warm sites, Douglas-fir and Ponderosa Pine. I’m having a very difficult time finding those, but I’m casting a net to improve the dataset. Also I failed to mention this, if there’s one thing you remember about this dataset, if you were to remember this metadata about this data, it is that all 18 of these sites, have been flushed by three of the highest flows on record, in the past 25 years. Those occurred in January of 1974, when there was a major rain and snow event that effected channels all the way to Helena, Montana. January of ’74, December of ’77, and most recently February of ’96. Look at the numbers, you have three major events in the past 25 years, that disturbance regime is extremely extreme. This exceeds the disturbance regime of channel resetting debris torrent regimes in Western Washington and Oregon. So the wood values, the wood that are in these channels, I would argue is, is at a historic minimum, because of the flushing events that occurred in the past 25 years. This is a weird dataset for that reason. We’re looking at wood populations flushed by major floods. Domoni?
Audience: Yeah, I’m trying to make the connection. You said most of the wood you XXXX was branch fall.
Speaker: There was a lot of branch fall, a lot of branch wood in the channel in various stages of recognition and decomposition. Of course there’s flotation, right? There’s other ways for wood to make it into the channel which includes rafts that move from up valley to down valley.
Audience: How did you go from the data you’ve got to your recommendations?
Speaker: The recommendations are based on creating conditions for self-replenishing wood supplies. And they’re based on looking at the entire data spread and taking a median. So for all my wood values, all my zone 1 wood values, my zone 2 wood volumes, my zone 3 volumes, looked at all seventeen sites, and this is the central tendency statistic. Average of all that data scattered.
Audience: But in riparian areas?
Speaker: Correct. For terrestrial and fluvial components.
Audience: Okay, average of the downed wood, or average of the standing trees?
Speaker: Average on the standing trees, the only downed wood I measured was in the channel. Zone one through four wood. I did not measure terrestrial wood outside of,
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or actually I did measure outside the bank for wood, but they had to have, the wood had to have a zone one component.
Audience: Okay, so then I still don’t get how you got to the recommendation. If you measured wood in the channel…
Speaker: I’m looking at the stand conditions that are necessary to create what I saw in the stream channel.
Audience: How do you figure that out?
Speaker: So basically what I did was I looked at all the structural conditions of all eighteen riparian forest plots and I took the, there’s quite a bit of scatter in the trees per acre, and the size classes, and I took the average, I selected a central tendency statistic, and I did the same for the wood, for all, at least four compartments, zone 1, zone 2, zone 3 and zone 4. Actually in your take home message, I cheated and I gave you a range. And I do like rules of thumb, geometric rules of thumb, one, two, four and eight. I think foresters or botanists or horticulturists are aware of the number of trees you would have to plant to account for mortality and at time X or time Y. Twenty or thirty or forty years up. So if you want average streams, maybe picking the average or the median or the mode is appropriate. I have no guidance on that.
Audience: Why not?
Speaker: ‘Cause I don’t’ believe there is a guidance on that.
Audience: If branches are a very important part, XXXX branches on small streams…
Speaker: Well it could be logging slash, restoration techniques, XXXX, to add some structure to the channel.
Audience: Okay, but from tree input, if you have a one, two, four, eight kind of a pyramid going down, wouldn’t’ large trees towering over be a better source of branches to fall? ‘Cause with small trees, the eight centimeters or less, the proportion of those that are going to be next to a stream, that make it into the stream, are going to be very few of those eight. There going to be distributed across the…
Speaker: You have to have plants that are, that have either weak branch attachment or have had something happen to them so they’ll shed their branches. You know the branches at the top, tops also break out too, so I’m not just focusing on branches attached perpendicular to a bough, smaller wood.
Audience: Would branches from large trees serve the same purpose as whole small trees falling in?
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Speaker: Probably. I guess it also depends on the dimensions of the fallen wood and the way they lay, the length of the fallen piece with respect to the bank full width of the channel. So it’s really a sizing thing. Scaling.
Audience: If you had the problem, the only thing I see in dealing with these small trees is or the portion of the real small trees, is that if you have those next to a stream, even ones right near the channel, there’s still a chance that might not ever make it to the active part of the zones…
Speaker: That’s true.
Audience:…but if you have big trees, near or towering over, there seems to be a much higher probability that gravity is gonna pull it, although it would still be called randomly, the branches that are kind of maybe overhanging small channels might be a more reliable source of wood…
Speaker: I agree. I should also add that one of the things I noted, particularly in stands that were dominated by Western Red Cedar, or other plants that have a needle attachment to twigs that combs out a lot off fallen snow, those are the tops that tend to collect a lot of snow and creak over and break. At least on one site, I observed of a lot of stem breakage due to snow. This year that’s obviously not an issue because of the low snow fall.
Audience: We notice this periodic or occasional channel flushing event. Do you have any information on whether that’s something that’s periodic, so we can go through periods of a channel flush then we recruit one of the dead….
Speaker: Periodic. Case in point, the precipitation of rain on snow event that occurred in February of ’96, I guess the meteorologists saw it coming, but most of us on the ground didn’t realize what actually, how strong or how long the duration of the storm was. But that was a real channel flushing event. And that was the largest flood on record for the Ahtanum stream flow, gauging set. That was estimated to be about a, having an occurrence level of about 80 years. So that wasn’t the largest, but it caused a lot of damage to public works, to stream adjacent XXXX roads, to culverts, bridges, you name it. And it moved a lot of wood. It brought wood in as well, and flushed it out.
Audience: Yeah, at one point you were talking about the difference between having lots of tight trees and maybe getting more branch fall there than with big ones.
Speaker: Yeah, I don’t know exactly how this works.
Audience: (inaudible) I would encourage you to check that assumption, just based on, I’m living in a place that’s got 30 inch trees, and at about 12 trees per acre, and I came home last week and almost the entire ground is covered in branches of four to six
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diameter. So that’s some nice pieces of wood coming down. Out of XXXX periods. So I’d just be cautious until you check that assumption. Speaker: Actually, I’d like to know more about the strength of branch attachment by species. That’s a real area of concern for arborists, people that do work on individual trees, particularly in urban areas, forest failure analysis and damage and insurance purposes. It’s a big thing.
Audience: Well yeah, you were talking about not wanting trees to grow too fast when basically, as trees grow, they prune themselves as they get bigger, from the lower end up. as trees grow, they self prune..
Speaker: (inaudible) Are they edge trees, in the middle of the stand plus shade?
Audience: Well, I don’t know…
Speaker: I agree. I’m generally hearing that trees will eventually self-prune.
Audience: So I guess I don’t, I guess I’m not seeing, kind of back to Domoni’s question, I can’t remember which, who had the question about the smaller trees, are they ever contributing to the stream channel that branches over the larger trees, that the odds of the branches getting into the stream are higher.
Speaker: They need to senesce and shed branches and so there’s a, there will be a point in time in their life span where if they haven’t died already because they’re entirely shaded out, because of competition from other trees.
Audience: Here a lot of them come up in snow, snow (inaudible)
Speaker: Right, right, or ice storms. Or unusual events where the woods brash (inaudible)
Audience: So I guess that’s, that goes back to my question. So what was your reasoning about not having trees that are, with less stress, that are growing fast over trees that are more suppressed that you talked about, how one side…
Speaker: My understanding, and it may be faulty understanding, my understanding of rapidly growing trees that don’t have a lot of shade in the crowns, is that they won’t shed branches as rapidly, or create as much, or senesce branches because the branches will remain alive, they won’t die out, because they have sunlight, they can photosynthesize, they retain…
Audience: So like a bunch of open growing trees kind of all bunched together…
Speaker: Well, help me here foresters, but doesn’t that depend on the amount of shade, crown, the stem density, the shading pattern of the crown?
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Audience: I think it does, but another thing you’re talking about (inaudible) if you’ve got a fast-growing tree and it’s a self-pruner, something that readily prunes itself, what you’re doing then is creating a little bit, having the fast-growing tree, providing it does prune itself, you’re creating something maybe this big (indicates with hands) when it does self-prune versus if you’re growing stuff up in the thicket then they’re going to be little tiny, so it doesn’t appear to me that necessarily you’re gonna accomplish what you want to accomplish by having these overstocked stands that don’t perform in terms of lateral volume. Audience: Is that what you saw in your sites, your undisturbed sites?
Speaker: As with any data there’s a lot of spread, a lot of spread in the data, which is, which happens everywhere. Some of the sites I saw had a lot of trees represented in all four size classes. Zero to 3 inch, three to nine, nine to twenty and over twenty. That was an unusual example. Western Red Cedar, Hemlock type, very unusual for what I expected to find in Eastern Washington, but was out there. And yet, a mile away, as the crow flies, another person’s site was entirely different stand conditions, more of a I’ll call it a savanna type structural appearance. A lot of trees in the 9 to 20 and over 20 inch size classes, not a lot of regeneration, not a lot of small conifers coming up, so there’s a lot of scatter that you’ll see in any of these datasets and I’m still trying to make sense of them. And I particularly want to make sense of Ponderosa Pine and Douglas-fir stands, because this dataset, flushed by three major floods in the past 25 years, is skewed towards stand conditions in cool, moist forests. Which is just one of the many players in forests in Columbia Basin and in Eastern Washington. But I keep trying. I continue to look for good P. Pine and Douglas-fir sites and actually I’ve got some good suggestions from you on Devil’s Gulch and Mission Creek and Negro Creek is another as well. Any other questions? I like this camera trying to follow me. What’s considered a small stream? I don’t think there’s any definition of that, the prescription’s team from the Ahtenum Watershed Analysis convened, we got together. We looked at the characteristics of these channels that I had made some calls on. Some interpretations on. And we came to an agreement on what sort of, what width characteristics they had and we came up with the characteristics of the valley width should not exceed 25 feet, the bank full width should not exceed 15 feet. They’re steep, they’re alluvial, they’re wooded, they’re not bedrock controlled. Steep is relative. You talk to a steelheader, 4% is steep. You talk to a rafter, a kayaker, 30% is not steep enough. We chose something between 10 to 30% as being steep.
Audience: I think you might be able to tie, how many, what proportions you want, to exactly how wide your stream is. (inaudible) the wider the stream is the longer, the less interaction trees on either side are going to have with each another. And they’re not going to drop their branches, they’re going to keep them as they grow up because they’re not, the branches aren’t going to reach over and start to shade each other out…
Speaker: I can see you’re thinking about this. I can see equations in your mind.
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Audience: The narrower your stream gets, the quicker they have interaction and start to compete with each other and prune. The quicker you get self-pruning. So on the narrower streams, it might be a different spread, but on the wider streams, maybe you start to rely on more on, smaller trees falling in from the side rather than wait for the larger trees to grow up and start to compete with each other and drop branches.
Audience: Did you look at all at stream side shrub contribution to the small….?
Speaker: Shrub contributions. Good question. I’ve hacked my way through a lot of dog- haired, XXXX, dogwood stands, but not at these eighteen sites. In getting to the sites it was pick and shovel kind of work, but I did not measure shrub contributions to this. Even in terms of shade production, or wood….
Audience: (inaudible) wood?
Speaker: Oh, good point. So what is small woody debris? I didn’t tell you what the numbers were. There are lots of methods for measuring L-wood. But not for S- wood, small wood. So the dimensions I came up with were obviously pieces smaller than a maximum size of 4 inches mid-point diameter in six feet in length. So it went down to a minimum size of one foot in length and 1 inch mid-point diameter. So there, you’d argue that well, you didn’t get all the small wood. Well, I didn’t want to measure all the small wood. I’d still be out there measuring and we’d have 10,000 pieces of small wood, and believe me, it’s expensive, so in effort to cut costs and try to make sense of this, I think I did a hell of a lot of work, even with my definition of small woody debris. If you want to define it in other ways, I would encourage you to do so, but I would also implore you to allow for parsing of your dataset so we can come up with comparable values. So we can compare oranges to oranges and apples to apples. Because there are many definitions of what large wood is, and it gets very frustrating when you’re looking at datasets trying to make sense of them, you often take these uncomfortable leaps of faith. What did this person mean? Often times you can reach them and talk to them about it, but they may be long gone or in Timbuktu and it’s prohibitive to try to connect with them.
Audience: You were advocating more diversity in the in size classes. And would you suggest that the prescription as is, you know, with the 30 and the 20 XXXX large trees, could that be backed off and then increase what our input, that needs to be certain smaller size classes also in prescription. Or are you saying XXXX the 21 and 30 we have now, that (inaudible)
Speaker: I would encourage pushing for more smaller diameter trees. My encouragement would be to encourage flexibility and explore the opportunities.
Audience: So in other words, it could be the policy that…
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Speaker: I’m not making a policy decision here, so if you’re asking me to do that, I won’t do that. (Laughter) I’m offering you suggestions for when you deal with DNR and Forest Practices forester about how to be creative. It may be an opportunity.
Audience: Comment. Within diversity, do you remember that slide where I started talking about four or five hundred large pieces per mile, just consider channel dikes and bedloads, and there’s A-1’s which is a narrow A channel like these with bedrock XXXX, A-2, big stuff, rock, there’s a lot of streams like that, particularly in the XXXX zones of the Cascades. Not so much on the Colville. Smaller stuff, A-3’s with cobbles then there’s A-4’s with gravels. You don’t see much in the way of A- 4’s, A-5’s and smaller in that steep of channel. And smaller pieces of hard wood in the A-3’s, A-4’s with cobbles and gravels can be very important in being a component of those steps. To get into, like I said, an A-1, well, you don’t worry about steps. That extreme bed being rock (inaudible) control between big boulders. So it’s variable. I don’t know if you agree with that statement or not, but again we’re getting to rules of thumb and if you look at the sites, there’s some sites you could argue, where wood isn’t as important. Some sites you could argue, small wood doesn’t contribute to the structure that much. But (inaudible) channels, the small bedload (inaudible) so it’s very important to get down there and XXXX those steps you can find a lot of small pieces of wood that to building what looks like a band of cobbles that created the dam that made the wedge. Does that make sense what I’m saying or am I rambling too much?
Speaker: No, you’re rambling and you’re making sense.
Audience: Okay.
Speaker: Any more questions? Domoni, take it away.
Domoni: Thank you. (applause) It was an interesting day. I think I learned a lot, I think most of us did. I want to thank everybody for coming. Do we have some sort of a guess as to how long it will take to get some sort of a write-up put together? Couple weeks or so. We’ll let you know and again if we have your email address, we’ll make sure you get it. So thank you everybody.
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