LONG-TERM SITE PRODUCTIVITY PROGRAM INTEGRATED RESEARCH SITES GOVERNING RESEARCH PLAN

Prepared by Susan Little Bernard Bormann Larry Bednar Trish Wurtz John Zasada Mike McClellan Lauri Shainsky James Boyle Mike Castellano Mike Amaranthus Connie Harrington Darlene Zabowski Mike Geist

RESEARCH PLAN FOR INTEGRATED RESEARCH SITES

INTRODUCTION The USDA Forest Service, USDI Bureau of Land Management, and other stewards of the land have been charged with the challenge of maintaining forest productivity for current and future generations. Forest productivity is the ability of the land to provide a combination of resource values such as fiber, water, air, quality experiences and biological diversity. Long-term site productivity is the capacity of the site to support forest ecosystems over generations of humans and trees, as measured against some defined reference. Our desire to maintain long-term site productivity, and the legal mandate to do so, includes a desire to maintain options for future use as well as the sustained production of the current mix of forest products and intangible resources. In this Research Plan we will refer to potential productivity--approximated by gross primary productivity derived from models, and referenced by indicies of soil quality and genetic potential--and to the net and cumulative production of specific products and forest attributes such as net primary productivity, wood volume, nesting sites, forage, and species diversity. Long-term site productivity is determined by the cumulative interaction of soil, biota, climate, natural disturbance, and human activity. Two recent proceedings capture current knowledge of productivity and have references for specific topics (Perry and others 1989; Gessel and others 1990). Nearly all forestry research contributes in some manner to our understanding of ecosystems and the management of forests. However, most research to date has focused on short-term responses of individual components of ecosystems to individual events and manipulations. Thus, a fragmented body of knowledge has evolved in which research methods and language are specialized by discipline and individual disciplines are pursued at different locations and scales. Although some individual processes and responses are adequately understood, integration and synthesis are difficult at best. The focus for the research proposed here was derived from discussions within a broad community of people interested in long-term site productivity (see Appendix). The specific objectives, hypotheses, and design were developed by the authors in response to that community's input. Two primary mechanisms by which forest management may influence long-term productivity were identified and form the basis for the two basic questions posed by this research plan. First, does altering the pattern of succession through species manipulations influence long-term site productivity? Second, does the amount, timing, and distribution of organic matter left on-site influence long-term site productivity?

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The Integrated Research Sites are being established as a network of long-term research sites to address these as well as other questions that are truly long-term and complex, and demand that research disciplines integrate in concept, in application, and in analyses. The IRS sites will provide a setting for continual observation, discussion, and involvement across disciplines, management, and interested publics. Research on these sites will be conducted in a 200-year context, allowing for several generations of crop trees. In order to provide for the needs of land managers in the near future--prior to completion of long-term studies-- research from these sites will contribute to conceptual and numerical modeling of long-term processes and responses on a continuing basis. Our desire is to provide a legacy of integrated information on productivity and to provide a context for basic research which will result in more efficient research and more successful incorporation of results into models. The Integrated Research Sites are the cornerstone of a broader Long-Term Site Productivity Program, led by the USDA Forest Service Pacific Northwest Research Station in cooperation with Pacific Northwest and Alaska Regions and with the USDI Bureau of Land Management, Oregon State Office. Research under the Program includes research on below-ground processes, retrospective and chronosequence research on site productivity, modeling long-term productivity to evaluate consequences of management decisions, and investigations on the effects of specific management practices on long-term site productivity.

REVIEW

Net Primary Productivity Sustainable forest productivity is the ability of the land to produce a wide array of products and values on a perpetual basis within broad environmental limits. Thus, the most appropriate measure of forest production is likely be an index which integrates across this array and quantifies values and resources such as timber, grazing, wildlife, fisheries, water, visually attractive landscapes, recreation, microbes, biodiversity, habitat and other ecosystem properties. Ideally, measures of sustainability would be derived from changes in overall production over long time periods, independent of changes in environmental limits. However, overall production is often unquantifiable because of widely varying units of measure, and changes in climate. Thus, surrogate measures of sustainability are needed that closely relate to the production of as many products and values as possible and at the same time can be directly measured. The LTSP Program will use total ecosystem production-- net primary production (Npp)-- and components of Npp as the principal surrogate measure of long-term site productivity. We do not, however, preclude use or development of other surrogate measures. Figure 1 presents the components of Npp, and forms the basis for the conceptual model which drives and will be driven by the research proposed here. Primary producers or autotrophs (plants) capture light energy through photosynthesis. Gross productivity (Gpp) is the cumulative dry matter added to the ecosystem through photosynthesis. Npp is Gpp minus the dry mass lost during maintanence and growth respiration (Ra): Gpp=Npp + Ra [1] Changes in net storage of carbon resulting from additions or losses are defined as net ecosystem production (NEP). Losses of carbon other than Ra result primarily from the respiration of heterotrophs (Rh). Heterotrophs are animals and non-photosynthetic microbes and plants that depend on the energy fixed in organic molecules during photosynthesis by autotrophs. Npp= NEP + Rh [2] NEP is defined as change in storage of carbon in all forms during a defined period and include changes in carbon content in plant, animal, and microbial biomass, and changes in detritus--all dead organic matter such as soil humus, litter, and downed logs. Further division of changes in biomass are useful, such as stem and forage production. These are often the type of production managers are most concerned with.

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Measurement of Npp can be problematic, mostly because of difficulties in quantifying belowground and detritus production, as well as other outputs or losses. Our approach follows that of Bormann and Gordon (1989), which focuses on three principal components of Npp: (1) soil respiration; (2) changes in soil organic matter; and (3) changes in aboveground biomass. Succession, Management, and Implications For Long-term Productivity Change is a fundamental characteristic of forest ecosystems. The rate and nature of change is a function of species composition (including plants, animals, soil organisms, fungi and other biota), site conditions, and the frequency and severity of disturbance in a given ecosystem. Succession is the sequence of change in biotic communities which occupy an area. Succession involves numerous processes by which species influence the physical environment and replace one another over time (Connell and Slatyer 1977, Bormann and Likens 1979, Kimmins 1987, Oliver and Larson 1990). The mechanisms of succession in biotic communities are complex; numerous mechanisms and pathways exist for a given site's progression from one set of species (or "sere") to another. Although seres are often described only in terms of the primary producers, i.e., plants, changes in plant composition can cause changes in other species (e.g., animals, soil organisms, and others). Conversely, animals and other organisms may be a major cause of change in the composition of the primary producers. Forest succession can be either autogenic, whereby organisms make changes in the site which favor the development of other species, or allogenic, whereby geologic or climatic processes cause changes in the physical environment which lead to changes in the biota (Kimmins 1987, Oliver and Larson 1990). In this research plan, we are concerned with secondary succession. Secondary succession is the progression of plant communities which occur following disturbances such as fire, windthrow, and timber harvesting. Secondary succession is distinguished from primary succession in that the former occurs on sites which have some level of soil development and previously supported vegetation. The species composing the forest vegetation which develops following disturbance fall into one of several categories (Kimmins 1987, Halpern 1988, 1989, Oliver and Larson 1990). Residual species occurred in vegetative form before disturbance and some portion of the plant survived the disturbance. These species can rapidly dominate a site and in extreme cases prevent the establishment of species which otherwise may have dominated later succession. Examples of these species developing from roots and rhizomes are Rubus spp., Populus tremuloides, Vaccinium spp., and Galtheria shallon. Others develop from basal sprouting Acer spp., Corylus, Salix spp., and Arbutus menziesii. A final group can develop by layering, one of the best examples of this is Acer cicinatum. Invader species become established from seeds entering the area from adjacent stands. Species of all of growth forms (trees, shrubs and herbs) can be part of this group. They can all establish at the same time; dominance is determined by growth rate and longevity. Examples of these species are Epilobium spp., Senecio spp., Alnus spp., Betula, many of the commercial conifers, and Salix spp. Another group of species are represented in the buried seed pool. These species may or may not be present on the site in vegetative form prior to disturbance. The classic examples are species which occur in the early successional flora but are only present in seed form in later successional stages. Following disturbance, seeds germinate and the species are present for several to many years depending on life form and growth characteristics. Some of the best examples are Ceanothus spp, but other examples are various Rubus spp., Geranium sp, Corydalus sp. and Sambucus spp. Knowledge of how different species recolonize disturbed sites will aid us in prescibing means of acheiving the different seral treatments. Three proposed mechanisms which determine the relationship among dominant species (and less obvious but important species such as nonvascular plants, soil flora, and soil fauna) and the pathways of succession include facilitation, tolerance, and inhibition (Connell and Slatyer 1977, Kimmins 1987). Facilitation occurs when individual species modify the environment in such a way that it becomes more suitable for the invasion of other species than for its own regeneration. Tolerance occurs when the environment is satisfactory for the establishment of any of the potential invading species, and species dominance is based mainly on which species happen to arrive first, their growth form, rate of growth, longevity, and the physiological ability to tolerate the current environmental conditions. Inhibition occurs when species modify the environment in such a way that prevents the recruitment of other species or significantly

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prolongs the recruitment period. These processes are not mutually exclusive and may all occur simultaneously on the same site. The importance of each will be determined by species composition, disturbance regime, and growth and reproductive characteristics of the species involved. Successional patterns following disturbances such as harvesting or wildfire are known to varying degrees in Alaska, Oregon and Washington (see for example Stewart 1978, Van Cleve and Viereck 1981, Franklin and Hemstrom 1981, Foote 1983, Alaback 1984, Kimmins 1987, Halpern 1988, 1989, Oliver and Larson 1990). Most research to date has focused primarily on changes in species composition and cover of trees and associated vascular plants. Some studies have dealt with nonvascular species and microorganisms. However there is little information on the relationship of changes among different trophic levels as a result of forest management activities. Forest management practices often result in shortening or eliminating some parts of the successional sequence. For example, use of herbicides or site preparation techniques in combination with planting favored timber species can result in a reduced duration of early seral species. As a result, the influence of some species is eliminated or reduced. The long-term impacts of practices which alter succession are not known in detail. The importance of some individual species whose tenure on a site is often shortened is known to some extent. The potential detrimental effect of the elimination of species such as alder and ceanothus, which fix nitrogen, can be assessed in a general way. However, there is little information on the role of other non-crop species in determining long-term site productivity or the effects of eliminating or reducing their time of occupancy. Forest management in the Pacific Northwest is evolving, particularly with respect to harvesting strategies. Past approaches used narrowly defined methods and blanket prescriptions. Now, case by case evalutations are made which seek to achieve landscape objectives as well as efficient production of timber. This evolution is leading to more partial cutting, uneven-aged management, and retention of individual trees or groups in an even-aged setting (e.g., Eubanks 1989). Some of the products and values tangible at the landscape-scale depend more on species composition, distribution, and stand structure than on achieving maximum growth of selected tree species. Thus, there is a need to understand the impact of management practices at the stand-scale in ways that relate to landscape-scale questions. In order to assess the effects of harvesting and other management practices on productivity, we need to be able to relate changes to easily identifiable states or stages of forest development. Forest successional development provides a framework for such assessments. This plan seeks to use this framework to examine the consequences of directed forest successional development and associated links of ecosystem structure and function, as they relate to productivity on various spatial and temporal scales. Organic Matter and Long-term Site Productivity Organic matter (OM) is any material containing carbon compounds that is derived from living organisms. OM refers to all such material, living and dead, on a site and to specific components, such as the forest floor, soil organic matter, and downed woody debris. Total system OM may be divided into categories defined by structure or function. Structurally, OM may be usefully divided into foliage, branches, stems, roots, standing dead, forest floor (including down logs and branches), soil organic matter (SOM), dissolved OM, volatilized OM, and animal biomass. Many functional definitions are possible also, with OM divided into photosynthetic, respiring, and detrital components or into categories based on relative OM recalcitrance, expressed as half-life or turnover time. A structural approach will be used in the design and implementation of this study. OM has multiple functions in forest ecosystems that may determine forest productivity. First, OM is the primary reservoir of nutrients essential to plant and animal growth. Second, OM is the energy source for heterotrophs, fueling most biological activities. Third, OM is a structural material that functions as a growth substrate (e.g., snags, down logs), as habitat, creates soil structure as an essential component of soil aggregates, and buffers ecosystems against physical forces. Examples of buffering activity include organic horizons that protect soil from erosion, plant canopies that moderate wind speed and radiative heating or cooling, and coarse woody debris on steep slopes and in stream channels that reduces the erosive power of

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flowing water. Perry and others (1989) provide excellent discussions on the role of organic matter in forest productivity in general, and Jurgenson and others (1990) discuss OM issues pertinent to the forests of the Inland Northwest. Research in the last 20 years on management effects on organic matter has concentrated on two main areas: the comparison between bole-only and bole-and-crown harvesting; and the effect of site preparation, primarily fire, on surface organic matter pools (S.U.N.Y. 1979; Ballard and Gessel 1983; Perry and others 1989; Gessel and others 1990; Walstad and others 1990). Both areas of research were motivated primarily by a concern for nutrient capital. Methods typically compared nutrient capital in pre-treatment sites with that removed during the management activity. Long-term effects have been predicted by comparing management losses to natural inputs of nutrients and through models of nutrient cycling (Kimmins and Sollins 1990). Ecological research on contributions of individual species to litter, decomposition, and below-ground processes have also been conducted, but seldom on the same sites as the harvesting research. Direct evidence of long-term impacts from intensive harvesting is weak, primarily due to the lack of long-term, controlled experiments (see Powers and others 1990 for synopsis of multi-generational studies and Dyck and Cole 1990 for a discussion of research needs). Harvesting and site preparation are the major ways by which forest management practices may influence site organic matter. Current National Forest Plans have standards and guidelines for retention of large woody debris and protection of forest floor. The intent of these standards is to protect long-term productivity. Economic trends have altered how harvests are conducted, with more reliance on whole-tree yarding and more complete utilization of individual trees than in the past. The question now is not whether to whole-tree or bole-only harvest, but how much material is to be left on site either as felled trees, or as specified pieces of residue classified by length, diameter or quality. Research is needed to compare organic matter inputs to the forest floor (and subsequently to the soil) as a result of harvesting in even-aged and uneven-aged settings. This research will be most fruitful if combined with studies of the different contributions of species groups to forest floor and soil through annual litterfall and turnover between harvests.

OBJECTIVES The research discussed in this plan has two primary objectives: I. To examine how potential and realized productivity are affected by the pathway along which succession is directed by management practices. All sites are capable of supporting a variety of forest conditions at any point in a seral sequence. These forest conditions can be described in terms of the species present, their vertical and horizontal distribution and abundance, amount of non-living organic matter, microclimate regimes, general state of health, as well as in terms of relative position of that site to others across the landscape. This research is designed to examine how conditions produced by directing the aboveground plant component of an ecosystem to a particular successional state or "sere" can affect subsequent ecosystem development and productivity. Forest conditions can be altered by management practices which affect composition by removal of species, addition of species, conversion of organic matter to different forms, and change soil physical and chemical properties. This research will focus on three distinct strategies for directing or arresting succession towards forest conditions which may have distinct differences in ecosystem production. These treatments include: (1) incorporating an abundance of early seral species into even-aged management of conifer crop species; (2) directing site resources exclusively to mid-succesional conifer crop species to the exclusion of other seral stages; and (3) emphasizing late seral species and forest structure along with the management of the crop species. A fourth treatment will be an unmanipulated stand, left untended throughout the duration. The crop species will be consistent across treatments within a site, but will not necessarily be consistent across sites.

II. To examine how altering the amount of periodic inputs of organic matter to the forest floor can influence long-term site productivity. The importance of organic matter will be examined by directly manipulating above-ground organic matter, primarily through the cutting and removal or retention of whole plants. Treatments will be defined as proportion of above-ground biomass to be left in a felled

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condition after each harvest. Hence, the stand-scale treatments will address the aspects of managing quantity of organic matter. Small-scale studies on these sites will look at issues of quality of organic matter, particularly as it relates to decomposition rates of different sized material, contributions of individual species to annual litterfall and SOM quality.

HYPOTHESES

The hypotheses listed below represent the central issues to be addressed by the IRS Research Team through the implementation of this plan. The primary null hypotheses target four broad categories: net primary productivity, biodiversity, soil organic matter, and soil physical properties. Within each category, alternative hypotheses are proposed, some of which include underlying mechanisms. Some of these hypotheses are stated in a testable form and will be directly addressed by the IRS design. In other cases, small-scale manipulative studies will be needed to test proposed hypotheses, particularly the more mechanistic ones.

Hypotheses will be tested within and between sites. Ideally, the ultimate test of most hypotheses concerning long-term site productivity would be an on-site bioassay of crop production after 200 years of subjecting each site to its array of treatments. In the meantime, the hypotheses will tested from periodic assessments of net and cumulative production, gross primary productivity, biodiversity, and soil attributes. We will be inviting other scientists to explore related hypotheses as an ongoing process, and will allocate space within the units to do so.

Net Primary Productivity

We will focus on three aspects of net primary productivity (Npp):

1. Annual Npp (aNpp)--the Npp accumulated over a year. This can be a measured accumulation for one year, or an average derived from total accumulation over a measurement period divided by the years in that period.

2. Cumulative Npp (cNpp)--the Npp accumulated from the initiation of the experiment to some reference point in time; and

3. The function of annual Npp over time.

For both annual and cumulative Npp indices, we will chose mid-rotation as our primary reference point in time. Mid-rotation is site-specific and defined as the halfway point through the rotation length, as determined by local foresters at the time of treatment prescription. However, we will continually monitor Npp and explore treatment differences throughout the experiment.

Null Hypothesis I: Net primary production (aNpp and cNpp) at mid-rotation and the shape of the aNpp function over time will be the same for all treatments-- for all species compositions and OM manipulations--and will not differ from that of the unmanipulated stand.

Alternatives:

1. Within an organic matter treatment, there will be differences in Npp between the different seral treatments. These differences in aNpp and cNpp should be evident by mid-rotation.

2. Although annual Npp at mid-rotation will be the same between all treatments, the cumulative Npp will differ: the early seral treatment will have the highest cNpp, and the natural stand will have the lowest cNpp.

3. Year of attainment of maximum aNpp will differ between treatments: the natural stand will begin at its maximum aNpp; the late seral treatment will achieve its maximum aNpp by mid-rotation of the first introduced cohort; the mid-seral treatment will achieve its maximum aNpp at the end of the first rotation; and the early seral treatment will continue to increase its aNpp throughout the second rotation.

4. Organic matter treatments will alter aNpp, cNpp, and the aNpp function.

Null Hypothesis II: The proportional allocation of production between ecosystem components is the same for all treatments.

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Alternatives:

1. There will be differences between treatments in the proportion of total Npp allocated to bolewood of the crop species. For a given organic matter treatment, this effect is expected to be measurable at the end of the first rotation. The mid-seral treatment is expected to have the greatest proportion of Npp devoted to bolewood, followed by the late seral treatment, then the early seral treatment. The natural stand is expected to have the smallest proportion of Npp allocated to bolewood at the end of the first rotation. These trends should continue through the second rotation. We expect that the early seral treatment will devote a larger portion of Npp to reproduction and annual litterfall. The natural stand will be approaching a relatively stable level of bolewood, and will be devoting a greater proportion of Npp to annual litterfall than the other treatments. The late seral treatment will fall between the mid-seral treatment and the natural stand.

2. Differences between the organic matter treatments in proportional allocation of Npp may not be expressed until the second rotation. Differences in proportional allocation of Npp are expected to be due primarily to differences in decomposition and nutrient uptake.

3. The proportion of Npp devoted to heterotrophic respiration (Rh/Npp) will be higher in treatments with more species diversity due to (a) enhanced diversity of litter quality and associated microbial populations, and (b) greater allocation of resources to reproduction than to structure.

4. The proportion of Npp devoted to autotrophic respiration (Ra/Npp) is expected to be higher in systems stressed by availability of water or nutrients or by pests and pathogens. Which treatments are more stressed than others will differ between sites.

5. The ratio of new heterotrophic respiration to old heterotrophic respiration (Rh-new/Rh-old) is expected to be the same between the early- and mid-seral treatments, but greater in the late seral treatment and in the natural stand.

6. It is likely that species composition and OM treatments will interact to influence aNpp, cNpp, allocation of Npp components, and the function of Npp over time. Each plant species present will have a unique effect on the physical and chemical environment, which will influence the diversity of microbial populations present, OM conversions, and subsequent Npp. In addition, OM treatments are likely to influence the presence and abundance of species colonizing the units by creating differential substrate microenvironments for germination. Persistence, dominance, and production by the species present may also be affected by OM levels through differences in nutrient cycling and soil temperature and moisture regimes, and potential herbivore habitat.

Biodiversity

Biodiversity in the context of this plan refers to the diversity of species present within a treatment.

Null Hypothesis I: There will be no differences in above-ground and below-ground species composition between treatments.

Alternatives:

1. Seral treatments, by definition, impose differences in above-ground plant species. We expect that there will be differences between seral treatments in the kind and abundance of insect, mammalian, and bird species utilizing the treatment units. These differences will be apparent within the first 10 years after initial entry, and are expected to decrease late in the first rotation, but increase during the second rotation. The causes of these differences will be changes in the diversity of potential habitat and food supply.

2. Low OM treatments will reduce diversity of below-ground species. This effect is expected to be measurable within 10 years after first entry because of differences in soil surface temperature, quality of forest floor and inputs to the soil organic matter.

3. The abundance and diversity of rodent populations will increase with increasing surface organic matter because of increasing diversity of habitat.

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4. Organic matter treatments will influence the plant biodiversity by creating different patterns in substrate and environment for germination.

Interactions Between Biodiversity and Npp:

Null Hypothesis I: Changes in biodiversity of plant species composition will not result in changes in Npp amongst treatments. Alternatives:

1. Increased plant species diversity will result in higher annual and cumulative Npp. Increased plant species diversity will result in greater utilization of site resources through divergent patterns between species in resource partitioning. It will also enhance Npp by increasing the diversity of soil microbial species which will improve utilization of below-ground resources. In the more diverse treatments, cNpp will increase with time most rapidly and early in the rotation, and plateau sooner than the less diverse treatments.

2. More diverse treatments will have higher aNpp and cNpp because they are more resilient to perturbations such as disease and insect outbreaks, and climate change.

Soil Organic Matter (SOM)

Null Hypothesis I: The amount and distribution of SOM will not differ between treatments.

Alternatives:

1. The organic matter manipulations will influence SOM. The amount of SOM will be greater in those treatments having greater retention of above-ground OM.

2. Species composition will alter SOM. The amount of SOM will be greater in the late seral treatments and the natural stands because of greater large woody debris and uninterupted litterfal contributed by late seral species.

Null Hypothesis II: The chemical and structural composition of SOM will not differ between treatments.

Alternative:

1. Early seral species will contribute greater amounts of leaf litter to the soil organic matter pool, while later seral species may contribute greater amounts of large woody debris. Decomposition and incorporation of surface OM into the soil profile will be influenced by the effects of different species and forest floor on soil temperature and moisture, and by their associated microbial species.

Null Hypothesis III: Soil development (depth and quality of individual horizons) will not differ between treatments.

Alternatives:

1. Species composition will influence soil development through effects on the microclimate and evaporative demand. Species composition will also affect soil development through their differential biological activity: leaf litter and woody debris fall; root growth and below-ground OM input; root exudation, nutrient uptake and ion exhange; plant species-specific microbial associations and their influence on the biochemistry of the soil.

2. Organic matter treatment will influence the soil development by creating different initial SOM inputs. OM treatments are expected to interact with species composition treatments to influence soil development. Plant and microbial species will interact to influence both each other and their environment, thus affecting the soil profile development.

Soil Physical Properties

Null Hypothesis I: The mean and variance of soil bulk density (and porosity, water holding capacity, aeration) will not differ between treatments after initial entry and at subsequent measurements through the second rotation.

Alternatives:

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1. The change in quality of OM inputs, amounts, and SOM distribution between treatments will alter soil physical properties directly and through change in the activity of soil microbes. For the early seral treatment, soil bulk density will decrease over the first rotation due to increased SOM and quality of litter. Soil bulk density will increase in the mid-seral treatment during the first rotation because of a decline in SOM.

2. In areas disturbed by treatment, there will be treatment differences in the rates of recovery of soil bulk density and porosity, due to differences in amounts and quality of organic matter inputs to the soil and subsequent effects on soil biology.

METHODS

Integrated Research Site Locations

Six sites in Washington and Oregon (Figure 1) and two in Alaska will be established as Integrated Research Sites. These sites are representative of the soils and forest types most likely to remain under management in the Pacific Northwest for resource outputs, including timber. Individual sites are described in Table 1. These sites are large enough to accommodate four replications of ten treatments applied at the stand-scale (8 ha).

Philosophy of Approach

No single research design can efficiently provide for research needs pertinent to all forest productivity questions. This research plan describes an approach to investigating questions tangible at the stand-scale (greater than 2 hectares) and smaller. The design described here will permit the quantification and comparison of supporting measures for resources tangible at larger scales but will not allow direct comparisons of populations that have larger home ranges. Opportunistic use of natural events, such as insect outbreaks and wildfire, may provide some insights for landscape-scale questions.

No single measure of production is adequate to assess forest productivity. A suite of measures and indices will be followed on these sites over time. Particular attention will be given to measures of primary production (plants) and the soils supporting that production. Assessments of quality and temporal and spatial distribution will be a part of all measures of production.

The following features are expected to facilitate integration of research results and activities:

1) Research will guide as well as be guided by, the development of conceptual models which provide a common framework and language;

2) Treatment prescriptions will be written in the context of local productivity concepts developed by interdisciplinary teams;

3) Small-scale, manipulative research on key processes and interactions will be conducted within the context of the stand-scale treatments;

4) Consistent methods for describing and analysing ecosystem components and processes will be encouraged;

5) Quality assurance will be an integral part of the program (QA plan to be appended); and

6) Data will be accessable through a common data base.

Overview of Experimental Design

A split-plot design will be used for each Integrated Research Site. Seral treatments will be applied to whole plots, and organic matter treatments will be applied to subplots. Whole plot treatments will be assigned in a randomized complete block design, generally with four blocks per site. This design is chosen primarily to minimize buffer areas by locating similar seral treatments on adjacent subplots. Other advantages include increased sensitivity to differences in organic matter treatments (which are expected to be smaller in magnitude than differences between seral treatments), and reductions in the number of timber sales required for imposition of treatments (which should result in greater economy and ease of execution of treatments).

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Seral treatments will be applied to whole plots which will be at least 45 ha in size, including 50-m buffers (Figure 3). Whole plots will be divided into three subplots for application of organic matter treatments. Within subplots, 1.5-ha mensuration plots will be established for monitoring stand-level effects (Figure 4). Destructive sampling will be limited in the mensuration plots. Separate destructive sampling zones for trees and other ecosystem components will be delineated from the onset, and dedicated to sampling at prescribed time intervals to allow opportunites for future scientists. Other areas will be reserved for small-plot investigations of varying duration. We anticipate space limitations on some of our sites and may not be able to provide space for small-scale investigations on all blocks. At least one complete replication per IRS will have such space reserved.

All foot and wheel traffic on plots will be confined to designated trails in order to protect the long-term integrity of the site. As much as possible, common transects and plots will be used to assess and sample the various ecosystem components and processes. Measurement crews will cover as many aspects as possible in one visit in order to reduce traffic impacts. There will be opportunities during treatment application (harvest) to remove whole shrubs and trees for more thorough stem, biomass, and chemical analyses. Within the destructive sampling zones, priority will be given to investigations that add to inference from mensuration plot. The majority of small-scale plots will be reserved for future generations of scientists in order to provide some incentive for continued scientific support of these sites.

Preliminary Site Assessment

A preliminary assessment of sites will be conducted prior to actual establishment of plot boundaries. This evaluation will include mapping soil and vegetation from ground and aerial assessments. This will include use of both high-altitude photography and video imagery obtained from low-level overflights with ultra-light aircraft. Presence of significant insect populations, diseases, or other influences of a spotty nature will be noted. The presence of Threatened, Endangered, or Sensitive species will also be heeded. This work is intended to ensure definition of blocks and plot boundaries which are consistent with the goals of the research.

Spatial correlations will be examined at each site by placement of transects on representative areas. Correlograms and spectral density estimates will be estimated and will be used subsequently to aid in development of more detailed sampling plans. Later sampling (post-treatment sampling, for instance) may be preceded by additional examinations of spatial correlations when changes are expected. Length and orientation of transects and measurement interval will be chosen to reveal information about spatial correlations at distances and directions expected to have important influence.

Plot Establishment

Treatment units will be blocked along variables locally considered to have the most significant influence on productivity of the site. Most likely, these will include soil differences, aspect, stand age and history, drainage, and local climate. Blocks will not be constrained to be contiguous, but may occur in separate drainages.

A locational grid will be established on each whole plot. A 20- x 20-m grid would seem appropriate, but this choice may be modified to meet site-specific needs. All distances will be measured as horizontal distance to reduce relocation error and to facilitate integration with Geographic Information Systems and aerial and remote sensing technologies. Compass declination used in plot layout will be recorded on forms and noted on corner stakes.

Whole plot and subplot corners will be monumented with 2-m labeled metal stakes. Mensuration plot corners will be monumented with 1.5-m labeled PVC irrigation pipe. Small-scale plot corners and grid intersections within the mensuration plots will be monumented with cedar stakes. Each whole plot will be signed, corners re-established, and cedar stakes replaced with more permanent PVC markers after application of treatments.

Travel corridors will be established on each subplot prior to treatment application. In addition to these formally delineated corridors, it is expected that lines between momumented points of the plot locational grid will attract traffic. Plots and measurements sensitive to such traffic will therefore generally be placed off the lines of the locational grid.

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Soil and vegetation maps will be upgraded after establishment of the locational grid. This mapping is expected to exhibit greater precision and detail than the maps created during preliminary assessments.

Vegetation surveys

Following plot establishment, a variety of permanent and non-permanent vegetation survey plots will be established both within and outside of the mensuration plot.

In the mensuration plots, every tree and sapling of 2 m in height or more will be tagged and measured, and a subset will be cored. Tree locations will be mapped in reference to the whole plot location grid. Descriptions of canopy structure will be developed, including maps of the type developed by Halle and others (1978) and Oliver and Larsen (1990). These maps show stand cross-sections illustrating spatial relationships among tree crowns and how individual trees interact to create the canopy structure. Fish-eye photography and other techniques will be used to measure understory light conditions as related to overstory condition. Representative trees from all crown classes will be selected for bole growth analysis as a part of treatment. Tree nutrient content will also be determined from these selected trees.

Nested plots will be established to quantify understory vegetation. Site-specific sizes for each of these plots will be determined by examination of relationships between plot size and variation of the statistics of interest on site. In the smallest plots, percent cover of mosses and small herbs will be estimated. In larger plots, percent cover and number of woody stems larger than 2-m in height will be determined for shrub and tree species. Herbaceous components of the understory will be described in terms of their spatial distribution and its relation to other vegetation strata. If possible, the bud bank of these species will be assessed and its response to harvesting and future stand development will be followed. Biomass will be examined over several growing seasons to estimate annual variation in this component of the vegetation. Residue will be assessed on the largest plot. Species, decay class, length, and end diameters within plot boundaries will be recorded. Some individual shrubs and logs will be marked and identified for repeated measurements.

If the forest type warrants it, a lightweight, portable platform will be used to allow researchers to work directly above the nested vegetation plots without trampling them. Trampling of plots will also be limited by use of sampling with replacement as outlined below. Only very minor collections of soil and plant tissue will be allowed within the mensuration plots.

A complimentary series of nested vegetation plots will be established in the destructive zones outside the mensuration plots. These will be used for development of site-specific assessments of chemical content and equations for estimating biomass of above- and below-ground components.

A series of permanent photopoints will be established within the mensuration plots, and their locations noted in reference to the established mapping grid (the permanent nested vegetation plots will be a part of this group of photopoints). At least seven photos will be taken from each photopoint periodically during the course of the experiment: a photo of 1 m2 of forest floor taken a short, known distance and direction away from the photopoint, a photo of 4 m2 of forest floor taken from the top of a step ladder at the same location, a photo taken horizontally in each of the four cardinal directions from the photopoint, and a photo taken straight up from the photopoint to document the forest canopy. A fisheye lens would be used for this last photo. Photographs will be taken at each of the photopoints periodically during the course of the experiment.

Location of nested vegetation plots.--Because comparisons of changes with time are of concern, survey plots used in pre-treatment surveys will be surveyed post-treatment. Location of plots during pre-treatment surveys therefore must consider needs expected of later surveys. Several concerns related to later sampling influence pretreatment sampling plans, and must be taken into account before pre-treatment plots can be located.

Sample plots will be located on a grid. The use of a grid offers several advantages including ease of relocation, favorable qualities towards the use of geostatistical techniques, and reasonable statistical properties (Haynes 1948, Milne 1959, Matern 1960, Cochran 1977). Because lines on the site locational grids are likely to be frequently traveled by researchers in post-treatment work, the sampling grid will be offset from the locational grid. Spatial correlation revealed by early pre-treatment assessments, expected

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later changes, and examination of adjacent areas with characteristics similar to those expected on plots will be used to modify the spacing of this sampling grid where necessary. Changes in spacing of the sampling grid may also require changes in monumentation of the locational grid to avoid traffic impacts.

Comparisons over time generally are more precise if the same plots are used repeatedly, but a great many remeasurments may eventually result in trampling and unrepresentative assessments. A compromise will be sought by use of partial replacement of sample plots at each sampling cycle. This limits the number of survey repetitions on a given plot, while still providing some repeated measurement of plots through time.

Further advantage will be offered by more precise specification of the way in which plots will be relocated at replacement. Changes with time are more precise when the same plots are used because values taken from the same experimental unit at different times are positively correlated. Many measures of interest in the present study are expected to show positive spatial correlations at small distances. Comparisons of two closely located plots measured at different times can therefore be expected to have some of the same advantages as remeasurement of the same plot. Partial plot replacement will therefore use new locations which are close to the previous locations. This technique will also preserve some of the advantages which argue for use of a grid of plot locations--sampling performed in this way will result in relatively small distortions of the sampling grid.

In each mensuration plot, the following plan will be used to determine plot locations. Within the mensuration plot four rectangular potential plot locations will described within each square of the locational grid (Figure 5). These will be arrayed in a 2 x 2 square pattern around the center of the grid square, with sides of the plots parallel to the sides of the grid square. These potential locations will be labelled according to the direction they lie from the center of the grid square. All grid squares on the mensuration plot will therefore have similar arrays of potential locations. One of these directions will be randomly selected. All grid squares will use this location during pre-treament survey and during the first post-treatment survey. A systematic sample of these locations will be designated as permanent and will be used throughout the study. All other plots will be subject to replacement by new plots at each survey. Partial replacement will begin at the second post-treatment survey. At this time, half the non-permanent plot locations will be randomly selected and moved clockwise to the next potential plot location within the same grid square. At the next survey, the remaining half will be moved in the same fashion. This method of replacement will be repeated for all subsequent surveys, unless unforseen developments argue against it. Seven surveys can be repeated in this way before the first location is used again.

Soil Description

Because destructive sampling will be limited on the mensuration plot, much of the soil description will be obtained from representative areas outside this plot. There will be a tendency for researchers with soils and vegetation orientations to work in distinctly different fashions during this study. Coordinated effort will be encouraged during sampling efforts. Of specific importance will be attempts to question the relationships between trees and associated vegetation distribution and the physical, chemical and biotic properties of the soil. The following activities will be undertaken to describe soil characteristics:

1. Permanent soil pits will be established outside the mensuration plot for pre-treatment description and future demonstration of the soil profile.

2. Standard soil physical properties such as particle size distribution, bulk density, soil structure, and others will be used to characterize current conditions. Information on vertical and horizontal variability of these properties will be necessary to fully assess preharvest conditions.

3. Soil organic matter and nitrogen will be sampled by horizon using soil cores. Soil sampling will be done in close association with the nested vegetation plots. For deep horizons, some subdivision will be necessary. Available nutrient levels will be pursued where feasible.

4. Soil respiration will be measured at the nested vegetation plots using portable infa-red gas analyzers. Methods are being developed to standardize and test approaches to measuring soil respiration. The contribution of below-ground autotrophic respiration to total soil respiration will be estimated through controlled environment studies.

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5. Belowground census of fauna and flora will be needed prior to treatment, the year of treatment, and the following five years. Population levels will be assessed for those species thought to be critical for productivity.

6. Preharvest samples of organic and surface soil layers will be taken at selected nested vegetation plots to assess the composition, quantity, and spatial distribution of species comprising the current seed bank in order to provide some insight into ecosystem and stand development. This sampling will be part of the soil sampling process.

Animal Populations

Due to the relatively small size of the treatment areas in this study, work with animal populations will be limited. Large mammals, such as deer and elk, have home ranges that are larger than the treatment units proposed in this study. Units in this study will be on the same spatial scale as most of the home ranges of smaller mammals such as mountain beavers and various microtines, however. Birds offer yet another situation.

The following actions will be undertaken as a minimum effort to document the relationship of proposed treatments with animal populations:

1. For large mammals, their preharvest utilization of the site will be determined by estimating browsing activity. Presence in the stand will be determined by making pellet counts. 2. For small mammals, trapping surveys will determine the species composition and distribution on the site. This work will be conducted over several years to follow annual variation in populations. Live trapping could provide an index of displacement following harvesting. The presence of mountain beavers is evident from their burrowing activities and heavy utilization of vegetation within their burrowing area. Mapping areas of observable activity prior to harvesting and observing post-treatment changes offers another potential route to assess the relationships between treatment and animal population dynamics. 3. Bird populations will be censused before and after treatment applications to determine the general changes resulting from treatments.

Insects and Diseases

The following activities will be undertaken in efforts to assess the relationship between insects, diseases, and imposed treatments:

1. Insect populations will be monitored in only the most general way prior to harvest. Species composition of the insects on the site will be determined. Soil insects will most likely receive more attention that other insects because of this study's emphasis on soil description. 2. The presence and distribution of tree diseases will be determined as part of the pre-treatment surveys. For root rots, the location of infection centers permanently identified.

Climatic Information

Each integrated research site will have at least one weather station at a representative on-site location. Within-treatment monitoring of the microclimate will be invited and pursued by scientists outside the IRS team as part of the analysis of processes and mechanisms underlying observed changes in productivity.

Sample Archiving

Samples of various types will be archived for later use. Vegetative samples will be archived for use in monitoring genetic changes associated with treatments. Other samples will provide standards and calibration materials by which results of future assay techniques can be meaningfully related to earrlier results.

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TREATMENT DEFINITIONS

Seral Treatments

The seral treatments proposed for this study are intended to result in significantly different successional states, as reflected by species composition, organic matter distribution, and forest structure. In defining treatments, we hope to achieve the essence of three distinctive successional patterns as simply as possible. Some conventions across treatments are necessary. These include:

1. Rotation length for crop trees will be defined in the local Forest Plan, and will be consistent across manipulated treatments, but may differ across sites. 2. Relative amounts of material remaining after harvest defining the OM treatments will be proportioned among above-ground components relative to pre-harvest distributions. 3. Harvest methods will be chosen that cause minimal disturbance to soil and residual stems. Harvest systems will be the best feasible for individual sites. 4. Site preparation methods causing minimal disturbance to soil and residual stems will be chosen. Also, consideration will be given to minimum preparation methods needed to achieve desired regeneration. 5. Reforestation will include planting of seedlings from local seed source of desired species at a spacing determined as more than adequate to achieve treatment. Once established, stands will be thinned to prescribed density. 6. Stand tending (thinning and pruning, primarily) will be minimal, and only that needed to achieve desired treatments.

Taking these conventions into account, seral treatments will be defined as follows:

1. Even-aged management of crop trees with incorporation of early seral species and curtailing late successional stages. Early seral species present on more than 50% of the unit, evenly distributed, for half of each rotation, with crown closure achieved at two-thirds through the rotation. This treatment would involve even-aged management of crop trees, wide spacing of crop-tree seedlings, maintenance of gaps in canopy through thinning, and maintenance of other preferred conditions for early seral species.

2. Devotion of site to even-aged management of crop trees to the exclusion of early and late seral species. Maintain closed canopy of crop trees over at least 80% of the rotation. Early successional stages will be shortened through aggressive site preparation, vegetation control, and close spacing of crop trees. Thinning and pruning would be conducted to assure maximum production of bolewood.

3. Uneven-aged management of crop trees with inclusion of late seral species and structure. Cohorts of the crop species in seral treatments 1 and 2 would be maintained through group selection. Group size could vary but minimum size would depend on limits for target species regeneration and early growth. Within harvested groups, individual trees and shrubs might be left over successive rotations, again, within requirements of target species. Under this concept, stands would include 3-6 cohorts, each group having a variety of ages/species within, but would consist primarily of target species of a single age. See Figure .

4. Allow a natural progression of species from the initial, undisturbed state through the duration of the study. This treatment would involve no management activity.

Site-specific prescriptions for achieving these treatments will be developed by multi-disciplinary teams. These teams will consider local influences (such as that of local fauna on productivity and the influence of these treatments on faunal species) as part of the prescription process. Prescriptions will be written in a 200-year context.

The species encouraged in seral treatments 1 and 3 will be selected based on local experience. Both these treatments may require planting or artificial seeding to insure the presence of desired species. It may also be necessary to reduce the presence of some species by a variety of control techniques. The actual implementation of the treatments will draw heavily on the experience of Forest and District silviculturists and others with local experience.

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Organic Matter Treatments

Three OM treatment levels are planned: high, medium, and low retention. The high and low OM treatments will bracket the widest range consistent with attainment of the seral treatment objectives. Low OM treatments will be achieved through whole-tree harvesting. However, the structural needs of the late-seral treatment may dictate some minimum level of retained OM for low OM treatments to provide the large live trees, snags, and down logs that characterize this seral stage. Residual OM at the medium treatment level will approximate the mean of the high and low treatments. The high OM treatment will be defined as the maximum that could be left while still successfully promoting early-seral vegetation in seral treatment 1. The light requirements for germination of early-seral species may require lower OM levels in the high OM treatments than might otherwise be selected. Only mechanical removal methods will be used to manipulate OM; fire will not be used to consume OM.

Treatments will retain organic matter from individual species and components in amounts that are proportional to their contribution to the total aboveground biomass at the time of harvest. This includes foliage, branches, stems, standing dead and down logs, and branches of all vegetative species. Roots, forest floor (excluding down logs and branches), soil organic matter, dissolved OM, volatile OM, and animal biomass will not be manipulated directly. Roots will be retained because removal is difficult without ground-based heavy equipment and significant soil disturbance--soils on all plots would need to be disturbed equally. Actual amounts of OM removed will be defined on a site-by-site basis. At each IRS, the standing crop of OM in each category will be measured prior to every treatment application.

Treatment description

Application of treatments will be documented in considerable detail for each subplot and whole plot treated. Descriptions will include site weather conditions, prescriptions, equipment used, disturbance due to treatment, and post-treatment distribution of organic matter.

ANALYSES

General Approaches

Retrospective analyses of representative trees from all crown classes will be conducted to examine the development of trees on the sites and how their growth has varied over time. Analysis of cores taken from trees on the mensuration plots will also contribute to an understanding of stand growth. From this analysis, mean and periodic growth of trees within the stand will be described, providing a comparison for future productivity. Tree nutrient content will also be determined from these trees.

A similar analysis of the woody component of the understory will be undertaken to more fully understand the dynamics of the understory and their relationship to conifer development. This information will be used to develop relationships between stem characterisics and total and annual biomass prodution.

The above-mentioned growth analysis will be assisted by comparison of on-site climate with nearby areas. When nearby areas have reliable weather records, it may be possible to make useful inferences about site climatic history using this off-site data.

Attempts will be made to use the stand and understory vegetation maps of mensurational plots to relate post-harvest growth of vegetation to the spatial distribution of vegetation prior to treatment.

Descriptive techniques will be used at all stages of data collection and analysis. Histograms, box-plots, and the like will be used to examine the distribution of statistics of interest across entire sites as well as within blocks, treatments, and vegetative strata. Data will be checked for spatial correlations which might affect sampling designs or later statistical analyses.

Statistical Analysis of Plot-level Information

When appropriate univariate measures can be developed, ANOVA may be used to test hypotheses. ANOVA will be applied only after descriptive examinations have been completed and indicate that the data to be suitable for ANOVA. The data will likely require transformation in many cases. One relatively simple model which might be used for a single IRS is:

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yijk = u + bi + tj + (bt)ij + Eij + gk(j) + (bg)ik(j) + eik(j)

where yijk represents a subplot response, u represents overall mean response, bi represents block effect, tj represents seral treatment effect, (bt)ij represents the interaction between block and seral treatment, Eij represents whole plot error, gk(j) represents the effect of OM treatment, (bg)ik(j) represents the interaction of block and OM treatment, and eik(j) represents subplot error.

This model states OM treatment to be nested under seral treatment, not crossed. Nesting is appropriate if OM treatment definitions will not extend across seral treatments. Although the proportion of organic matter to be retained on site will most likely be consistent across seral treatments, the absolute amounts will vary. If definition of OM treatments were consistent across seral treatments, the model would need to be modified accordingly.

If only one replicate per block is installed, no exact estimate of either whole plot error or subplot error will be available. It is usual in such a case to assume higher order interactions to be zero. This assumption is justified by the recognition that higher order interactions are usually smaller in magnitude than lower order interactions. If any terms are to be assumed zero, and if no other information to guide a choice is available, the high order interactions are the most sensible choice. If that assumption is correct, mean squares for those interactions are unbiased estimates of error. If this assumption is in error, these estimates contain components due to both error and interaction, and are biased towards values in excess of the true error. F tests developed using those estimates in the denominator will be correspondingly biased towards low values - acceptance of hypotheses of no treatment differences.

Due to space limitation at sites, it is probable that the interactions between block and seral treatment, and between block and OM treatment will be assumed to be equal to zero. If treatment differences for either set of treatments vary from block to block, a different approach must be developed. Because of this, the need for simultaneous application of treatments within all blocks is accentuated. Simultaneous application of treatments will reduce chances of confounding effects of seasonal differences.

It should be noted that analysis based on this model provides conclusions specific to the treatment factors and responses represented. Deeper questions about mechanisms which might account for the observed data are not addressed. That information must be obtained by other approaches, including on-site, small scale experiments. A complex and interacting set of mechanisms might show great changes without overall change in productivity as tested by a model such as the one stated above.

An extension of this model for use with data from several sites can be suggested:

yhijk = u + sh + bi + tj + (sb)hi + (st)hj + (bt)ij + Eij + gk(hj) + (bg)ik(hj) + eik(hj) The model parameters are used as in the previous model, with the addition of sh to represent site effects, (sb)hi to represent interactions between site and block, and (st)hj to represent interactions between site and seral treatment.

Note that subplot effects (the second line on right-hand side of the model) are now nested under site/seral treatment combinations. This nesting is appropriate if seral treatments are expected to vary from site to site. Such nesting is appropriate if a treatment cannot be adequately represented by reference to the treatment alone, but also must include knowledge of the site to give a complete representation. It should also be noted that while all treatments will be implemented on each site within a given year, all sites will not be treated the same year. This means that site will be confounded with year of treatment implementation.

The multi-site model represented above requires the same assumption of zero interactions as the single-site model discussed previously. The desirability of simultaneous application of treatments on all blocks within

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a site also holds. In addition, differences in timing of treatment applications between sites will result in confounding of effects of site. This may be especially true in early years, when climatic differences between years may result in different rates of establishment and growth of various species. Site differences are expected to be much larger in magnitude than seasonal differences, however, so this confounding is not expected to present major difficulties.

It is likely that more complex models which include one or more important covariates will be frequently used. The models presented here are likely more simple than those which will be applied later.

AUTHORIZING DOCUMENTATION, RESPONSIBILITIES, AND REPORTING

Establishment and maintenance of these sites are authorized by the Program Charter. Each site will need a detailed operation plan, will need to be identified in the Forest Plan or addendum to the Plan as part of the monitoring network, and will need to be recognized on all geographic records (TRI, GIS).

A scientist on the IRS team will serve as coordinator for an individual site, serving as the primary liaison with the hosting forest, and as the "gate keeper" for research activities on that site. The team will develop a common research approach across all sites, with treatments tailored to the individual sites. All six members will work in some capacity on all six sites. On-site research activities will be coordinated with forest personnel.

Funding of research activities will be through a combination of Program funds and participating research programs.

Coordination of Forest Activities.--Each of the hosting Forests for the Integrated Research Sites will have a site manager who will: (1) oversee installation of treatments and data collection for monitoring variables; (2) coordinate research and management activities with respect to the Forest Plan, Forest timber sale program, and corporate information systems (TRI, GIS); and (3) oversee contracts and budgeting for site activities. This coordination role will likely be a full-time responsibility for the first 3 years.

Region 6 funding of IRS activities will be coordinated by the Regional Office and will subsequently be allocated to the hosting Forests. Costs of implementing treatments that contribute to forest targets will be born by the Forest.

Responsibility for site establishment, treatment implementation, and site maintenance reside with the Forest. The hosting Forest is in the best position to accomplish these needs. Treatments will contribute to accomplishment of Forest targets. Boundary survey and marking is part of timber sale process. The Forest should be cognizant of site location and needs at all times in order to efficiently plan target achievements and to be alert to any special considerations when establishing future targets.

Pre- and post-treatment and periodic surveys will be part of the forest monitoring program. Detailed response information is needed to evaluate the usefulness of monitoring techniques and guidelines. Measurements and samples to be taken include inventory of existing vegetation, vegetation establishment and growth, dead material, and soil conditions. Because this work will assist in evaluating the effectiveness of monitoring standards and guidelines for all forests, the cost of doing work should be born at the Regional level. The actual doing of the work will be done by the host Forest or contracted to research, or to a private firm or interest group. Some of the work could be shared by a team of specialists from all cooperating land owners. Research will help establish the standards and protocols for these inventories, and facilitate technical training and/or contracting.

Documentation in the planning process and NEPA concerns will be addressed in the individual operation plans for individual sites. NEPA documentation for each site will address concerns for all treatments anticipated over a 50 year period. The Program will work with the hosting Forests in developing this documentation. This Research Plan and appended standards and guidelines will be used to write Forest-specific addendums to the Forest Plans.

Role of Cooperators--Cooperators include Bureau of Land Management, Bureau of Indian Affairs, other federal and state agencies, private industry, tribal councils, and local interest groups. The BLM will play a major role, including financial and technical assistance, participation in developing research questions and approach, contracts for individual studies or research and monitoring activities, and cooperative

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participation on the ground to accomplish research and monitoring goals. We have interest and commitment from other cooperators for each of these roles as well.

DURATION AND COST

This Research Plan is the guiding document for all Integrated Research Sites. It is hoped that these sites will be maintained indefinitely. The Research Plan will be reviewed every 5 years with the Long-Term Site Productivity Charter to assess the need for additions or updates.

The total research appropriated funds needed for these sites, exclusive of Program overhead, will be $1 MM annually in the first 5 years. Long-term monitoring and additional studies are likely to require $500 M per annum. Establishment and maintenance of the Integrated Research Sites will be largely supported by participating management agencies, who may also contribute to research efforts directly or indirectly.

COORDINATION WITH OTHER EFFORTS

Coordination with NFS and BLM related activities will be promoted through active participation in the Integrated Research Team and on the LTSP Program coordinating committee by staff specialists. Coordination with several concurrent research programs will facilitate the sharing of ideas, data protocol and data, and assisting in joint syntheses. Direct cooperation will be sought with the following:

Coastal Oregon Productivity Enhancement Coop: The Integrated Research Site on the Siuslaw National Forest will be the COPE site for reforestation research.

Long Term Site Productivity Program will provide Global Climate Change with vegetation and soil process response to climate.

We hope also to be part of the Forest Health monitoring network, both within the Forest Service national program and with the EPA EMAP Program.

Links with many of the above programs will come from having members in common, including COPE, New Perspectives, and Forest Health and Productivity in a Changing Atmoshphere Environment. The LTSP Program will take advantage of existing research sites for much of its research not directly involved in the Integrated Research Sites. Work already in progress on the H.J. Andrews Exp. Forest LTER site will provide some groundwork and guidance to the Program in terms of fruitful hypotheses to test and sampling designs in complex ecosystems.

Coordination with other research efforts will be through scientific exchange, sharing of research ideas, methods, and protocols, and by facilitating the inclusion of research on Integrated Research Sites that initiates under these other programs.

ENVIRONMENTAL IMPACTS

Treatments will reflect management practices. Their implementation will require standard environmental analyses, timber sale contracts, service contracts, etc. Small-scale investigations will be imposed to determine process-level responses and thresholds. These treatments typically fall under the categorical exclusion for research with regard to environmental analyses.

Environmental analyses of forest management activities will be aided by program research. By the very nature of the subject, the environmental consequences of individual and collective activities on research sites will not be known. Some of the treatments and on the ground activities will be typical of standard practices and will be covered by the environmental analyses conducted by the local management agency. Lead scientists will assist in the environmental analyses for research requiring adverse treatments unfamiliar to the participating office.

6-YEAR TIMELINE FOR RESEARCH ACCOMPLISHMENTS

FY 1991: Establish all sites in Region 6: lay out boundaries, recognize sites in Forest GIS data bases and other records as appropriate. Begin timber sale planning. Write Forest Plan addendums. Begin initial surveys and monitoring on at least three sites.

FY 1992: Begin initial surveys and monitoring on remainder of sites. Write prototype contract for treatment application(s). Schedule initial treatment for first three sites for FY 1993.

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FY 1993: Implement initial treatments on at least three sites. Schedule treatment for remainder for FY 1994.

FY 1994: Implement initial treatments on remaining sites. Intensive post-treatment work on all sites.

FY 1995: Integrated sites: Intensive post-treatment follow-up. Draft IRS update. Begin using IRS sites as demonstration sites.

LITERATURE CITED

Alaback, P. 1984. Secondary succession following logging in the Sitka spruce-western hemlock forests of southeast Alaska:implications for wildlife management. USDA Forest Service Gen. Tech. Report PNW-173. 26 p.

Ballard, R. and S.P. Gessel (eds). 1983. I.U.F.R.O. Symposium on forest Site and continuous productivity. Seattle, WA 22-28 August 1983. Portland, OR: USDA Forest Service Pacific Northwest Res. Sta. Gen. Tech. Rep. PNW-163.

Bormann, B.T. and J.C. Gordon. 1989. Can intensively managed forest ecosystems be self-sufficient in nitrogen? For. Ecol. and Mgt. 29:95-103.

Bormann, F.H. and G.E. Likens. 1979. Pattern and process in a forested ecosystem. Springer-Verlag, New York. 253 p.

Cochran, W.G. 1977. Sampling Techniques (3rd ed.). John Wiley & Sons, New York. 428 p.

Dyck, W.J. and D.W. Cole. 1990. Requirements for site productivity research. In: Dyck, W.J. and C.A. Mees, eds. Impact of intensive harvesting on forest site productivity. Rotorua, New Zealand: Ministry of Forestry, Forest Research Inst. FRI Bull. 159. pp 159-170.

Eubanks, S. 1989. Applied concepts of ecosystem management: developing guidelines for coarse, woody debris. In: Perry, D.A., R. Meurisse, B. Thomas, R. Miller, J. Boyle, J. Means, C.R. Perry, and R.F. Powers (eds). Maintaining the long-term productivity of Pacific Northwest forest ecosystems. Timber Press, Portland OR. pp 230-236.

Foote, M.J. 1983. Classification, description, and dynamicsof plant communities following fire in the taiga of interior Alaska. USDA Forest Service. Pacific Northwest Research Station. Res. Paper PNW-307. 108 p.

Franklin, J.M. and M.A. Hemstrom. 1981. Aspects of succession in the coniferous forests of the Pacific Northwest. p. 212-229. In D.C. West, H.H. Shugart, and D.B. Botkin (eds). Forest succession:concepts and application. Springer-Verlag, New York.

Gessel, S.P.; D.S. Lacate; G.F. Weetman; and R.F. Powers. 1990. Sustained Production of Forest Soils. Proc. 7th N. Amer. Forest Soils Conf. July 1988; Vancouver, B.C. Faculty of Forestry, University of British Columbia. 526 p.

Halpern, C.B. 1988. Early successional pathways and the resistance and resilience of forest communities. Ecology 70: 1703-1715

Haggland, B. and G. Peterson (ed). 1984. Broadleaves in boreal silviculture - an obstacle or an assett? Sveriges Lantbruksuniversitet, Institutonen for Skogsskotsel. Rapporter Nr 14. 252 p.

Halpern, C.B. 1989. Early successional patterns of forest species: interactions of life history traits and disturbance. Ecology 70: 704-720.

Haynes, J.D. 1948. An empirical investigation of sampling methods for an area. M.S. Thesis, Univ. of North Carolina.

Jurgenson, M.F. and others. 1990. Soil organic matter, timber harvesting, and forest productivity in the Inland Northwest. In: Gessel, S.P., D.S. Lacate, G.F. Weetman, and R.F. Powers. Sustained Productivity of Forest Soils. Vancouver, BC: University of British Columbia, Faculty of Forestry. pp 492-415.

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Kimmins, J.P. 1987. Forest ecology. Macmillan Publishing Co. 531 p.

Haeussler, S. and D. Coates. 1986. Autecological characteristics of selected species that compete with conifers in British Columbia: a literature review. British Columbia Ministry of Forests FRDA Report 001. 179 p.

Matern, B. 1960. Spatial Variation. Medd. fr. Statens Skogsforsknings Institut., 49, 5, 1-144.

Milne, A. 1959. The centric systematic area sample treated as a random sample. Biometrics, 15, 270-297.

Oliver, C.D. and B.C. Larson. 1990. Forest stand dynamics. McGraw Hill, Inc., New York. 467 p.

Perry, D.A., R. Meurisse, B. Thomas, R. Miller, J. Boyle, J. Means, C.R. Perry, and R.F. Powers (eds). 1989. Maintaining the long-term productivity of Pacific Northwest forest ecosystems. Timber Press, Portland OR. 256 p.

Powers, R.F. and others. 1990. Sustaining site productivity in North American forests: problems and prospects. In: Gessel, S.P., D.S. Lacate, G.F. Weetman, and R.F. Powers. Sustained Productivity of Forest Soils. Vancouver, BC: University of British Columbia, Faculty of Forestry. pp 49-79.

State University of New York. 1979. Proceedings, impact of intensive harvesting on forest nutrient cycling. Syracuse, NY: S.U.N.Y. School of Forestry. 421 p.

Stewart, R.E., 1978. Origin and development of vegetation after spraying and burning in a coastal Oregon clearcut. USDA Forest Service Res. Note PNW-317. 11 p.

Tappeiner, J.C., J.F. Bell, and J.D. Brodie. 1982. Response of young Douglas-fir to 16 years of intensive thinning. Oregon State University, School of Forestry. Research Bulletin 38. 17p.

Van Cleve, K. and L.A. Viereck. 1981. Forest succession in relation to nutrient cycling in the boreal forest of Alaska. p. 185-211. In D.C. West, H.H. Shugart, and D.B. Botkin (eds). Forest succession:concepts and application. Springer-Varlag, New York.

Walstad, J.O., S.R. Radosevich, and D.V. Sandberg, eds. 1990. Natural and prescribed fire in the Pacific Northwest. Corvallis, OR: Oregon State University Press. 317 p.

West, D.C., H.H. Shugart, and D.B. Botkin. 1981. Forest succession: concepts and application. Springer-Verlag, New York. 517 p.

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Table 1. Description of Integrated Research Site locations. FORKS DNR near Sappho Soils: Glacial till with deep forest floor Species: Hemlock, Douglas-fir, and spruce with scattered hardwoods Elevation/topography: 50 - 150 m; large benches with small draws Age: 70 years Past History: Railroad logged with long reaches. No surface evidence of physical damage to soils. Blowdown prevalent from previous stand Pathogens: mistletoe, some rot pockets GIFFORD PINCHOT: Siouxon Planning area, east of Amboy Soils: Colluvium and residuum, gravelly sandy loam to gravelly loamy sand moderately coarse. Species: Hemlock, Douglas-fir, some true fir and hardwoods Elevation/topography: 700 - 950 m; relatively even slope of 55-70% Age: 80-90 years Past History: severe wildfire. Very little residual material left from previous stand. Some windthrow. Pathogens: mistletoe, small pockets of root rot. SISKIYOU: Illinois Valley District, Oregon Caves (just SE of Caves) Soils: Colluvium & residuum of metavolcanics or granitic diorites. Species: Douglas-fir/ true fir. productive sites Elevation/topography: 1300 - 1700 m; even slopes and ridgetops (20-40%) Age: 80-120 Past history: wild fire origin, some residual material from previous stand Pathogens: mistletoe, truffles, weird wasps on shrubs SIUSLAW: Alsea and Mapleton Districts Soils: Preacher/Bohannon, deep loams Species: Douglas-fir, hemlock, alder Elevation/topography: 300 - 600 m; slopes somewhat dissected Age: 120-150 Past History: stand replacement fire, even, vigorous growth. Some windthrow. Pathogens: little root rot, wind-snaps, no insects UMATILLA: West Sinks planning area on Walla Walla District, 7 mi E of Tollgate Soils: ash mantle (14-40") over residual basalts. Very uniform Species: Douglas-fir/grand-fir, Englemann spruce, larch, lodgepole Elevation/topography: 1200 - 1400 m; very gentle slopes Age: Mostly 200+ SW corner has tight stand of D-fir/lodgepole that appears to be younger, perhaps following more recent fire Past history: No previous human activity save a fire trail through south end Pathogens: nothing pervasive WILLAMETTE: Blue River District, Isolation Block south of Vida Soils: gravelly loam/loam, deep, relatively homogeneous Species: Douglas-fir, hemlock, with alder/maple in draws Elevation/topography: 400 -600 m; undissected slopes Age: 80-100 years Past History: stand replacement fire with evidence of previous stand Pathogens: little evidence of pathogens

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Table 2. Minimum measures for Integrated Research Sites. Subject Measure Approach Trees >2m height location census dbh census height census cores (pre-treatment) sampled Canopy maps of structure sampled Shrubs % cover by species sampled # stems by species sampled Understory vegetation map by strata census % cover by species sampled Residue species sampled end dob and length in plot sampled decay class sampled Soil soil map census depth of horizons sampled particle size distribution sampled bulk density sampled soil chemistry sampled soil biota sampled seed bank sampled Large mammals vegetation utilization sampled pellet counts sampled activity locations sampled Small mammals population estimates sampled activity surveys sampled activity locations sampled Birds population composition sampled Insects species composition sampled Diseases presence/absence census infection center locations census Weather daily weather records one station per site

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APPENDIX I: HISTORICAL PERSPECTIVE ON INTEGRATED RESEARCH SITES

Congressional mandates, public interest, and lack of synthesis of fragmented and short-term research all contribute to the need for long-term site productivity research. The Oregon and California Railroad Act of 1937, for example, which covers BLM lands, states that "Lands valuable for timber shall be managed for permanent production...in conformity with the principle of sustained yield." The Federal Land Policy and Management Act of 1976 and the National Environmental Protection Act of 1969 further state that federal forest lands are to be managed without "substantial and permanent impairment of the productivity of the land." No legal interpretation of this provision has been established, but the Office of General Counsel believes it refers to "long-term" soil productivity (the WO-National Forest System Soil Productivity Task Group, Sept. 9, 1987). The current scarcity of relevant scientific results has contributed to an increased uncertainty and skepticism about the appropriateness of current forest practices, both with regard to timber production and other resources. This lack of trust in federal land stewardship leads to a greater probability that forest management activities on federal lands will be increasingly legislated or controlled by judicial decisions and/or legislative decree.

In the last decade, several symposia and workshops addressed long-term productivity concerns (e.g., Ballard and Gessell 1982, Slaughter and Gasbarro 1987, Perry and others 1989, and Gessell and others 1990). The proceedings of these meetings have documented the latest in productivity research. Some papers attempt to synthesize and give a holistic perspective, but supporting evidence, especially integrated research, is scarce. An I.U.F.R.O. subgroup, Management Impacts on Site Productivity, meets annually in the Pacific Northwest to exchange ideas and updates on research activities. An international group meets through the International Energy Agency for a similar purpose. Although these two groups in particular are multi-disciplinary, and provide for timely and interesting interchanges amongst scientists, the discussions have not led, in and of themselves, to intensive interdisciplinary research. Although they can act as catalysts, these volunteer organizations cannot provide funds or administrative support for large-scale, long-term research.

Recognizing the need, the Pacific Northwest Research Station established its Long Term Site Productivity Program in 1989. The Program's charter is to promote integrated, long-term research on productivity issues, develop common conceptual models, language, and protocols amongst the related disciplines, and synthesize existing and developing information in ways that help evaluate the long-term consequences of forest management activities. The underlying philosophy of the Program is that long term research can only be useful and will only be sustained if it is based on interactive participation within the scientific community, with public and private land managers, and with the public. Long-term research will only hold its appeal over the generations if it addresses the fundamentals of productivity in a way that lends insight to management effects regardless of what the management climate is at the time.

Dialogue was initiated in a series of meetings with local managers, scientists, and publics throughout Oregon, Washington and Alaska in 1989. The consensus from these discussions was that research was needed on the fundamentals of productivity, that long-term research was necessary and desirable, and that it should be conducted within a silvilcultural framework (i.e., within the context of decisions made over sequential rotations). Consensus was that emphasis should be given to effects on organic matter and soil physical properties. Insects, disease, habitat, species diversity, and forage should be monitored as part of the research process. Comparison between silvicultural systems that are perceived to be fundamentally different (even- vs uneven-aged management) were thought to be the most fruitful now and in the future. Additional studies are needed to evaluate ways to compensate for productivity loss or to improve productivity through physical activities, fertilizing, and genetic improvement.

In 1990, scientists volunteering from the Station and Oregon State University formed a team under the direction of the Program to design the research documented in this plan. The team evaluated the ideas from the open discussions of the previous year in light of past and current research. Specifically, the team asked what questions within that context are truly long-term? What questions make sense to address on a regional basis--is there a need for answering questions in a Pacific Northwest, rather than in a local context? Can we design research that gets at the fundamental issues of long-term productivity rather than merely demonstrating the advantages or disadvantages of a few current ideas on management? How can

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we integrate research on topics that are typically investigated in different temporal and spacial scales? This document is the team's answer to those questions.

True to the interactive philosophy of the Program, the team sought broad review of their central themes before solidifying the research approach. A concept paper was sent to all who had participated in the 1989 discussions, members of the I.U.F.R.O. subgroup on Management Impacts on Productivity, the IEA Productivity group, and other interested scientists and land managers. Eighty people responded, sixty of those in writing. Response outside of the scepticism for long-term research was overall favorable. Several positive suggestions were made and are incorporated in this research plan (see below for team's response to review comments).

Integrated Research Sites will be sites of intensive scientific study. Although substantial detail will be developed for these sites, they will represent only a portion of the lands under management in any geographic location. Hence, a broader distribution of sites is needed if we are to develop the mensurational and ecological tools to support the development of prescriptions. Geographic breadth will be gained by supplementing the Integrated Research Sites with Satellite Sites spread across forest ownerships. Treatments on satellite sites will be a subset of treatments on Integrated Sites coupled with treatments reflecting management practices of local interest. Research on these satellites will typically be more mensurational than process-oriented and therefore less intense.

RESPONSE TO REVIEW COMMENTS RECEIVED ON ORIGINAL CONCEPT PAPER

The first section treats suggestions for alternative questions to ask in the IRS framework, the second responds to suggestions as to how to conduct the research.

IDEAS FOR ALTERNATIVE/ADDITIONAL TREATMENTS

1. GENETICS: Effect of genetically improved stock on LTSP through rapid growth. The idea behind this is that stock is improved to promote more rapid growth than local seed source. This may lead to more rapid nutrient and soil carbon drain than would otherwise occur, both through increased accumulation of carbon and nutrients in the boles, and increased frequency of removing that material by shortened rotation lengths. Response of team: Reject as core, stand-level question. This question is very specific to local genetic stock and practice. The question cannot be answered without also looking at rotation length and utilization standards as well--IRS will not be large enough to pursue this question. We do plan to look at response of individual plants/trees on a small plots within the IRS. There are probably better opportunities to pursue this question on progeny test sites and on industrial forest land which may have existing stands of improved stock coupled with growth and yield information that is site specific. LTSP program may be able to look into this question later with the Tree Improvement Coop.

Role of biodiversity in maintaining LTSP. Response of team: The successional pattern question is our attempt to look at species and structural diversity. Genetic diversity within species may be addressable in a minor way on a small plot basis. We do intend to look at below ground diversity as well as above ground diversity over time.

2. SPECIFIC PRACTICES TO IMPROVE PRODUCTIVITY From Alaska: removing forest floor or allowing more light to reach forest floor to hasten decomposition. Low decomposition rates lead to build up of forest floor which in turn insulates soil so that it remains cold. Productivity might be improved by removing or reducing that insulation. Response of team: Our series 2 (limiting factors) question has been redefined to look specifically at the role of soil organic matter in long term productivity. Are there upper and lower thresholds of organic matter (quality/quantity/distribution over space and time) relative to forest productivity? In that series, a modification of forest floor amount and environment would be a logical step in Interior Alaska.

Nurse logs to provide sites for reproduction on excessively wet soils. Response of team: Although this may be addressed on specific sites, regeneration questions in and of themselves are not sufficient for long term research.

Rehabilitation of degraded sites (esp. with regard to relative cost/benefit). Response of team: This may be a factor in the revised series 2 question. LTSP Program hopes to look at soil disturbance/compaction and rehabilitation in a broader context than the IRS would allow.

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3. COMPARING PRACTICES General response: The team feels that comparing current practices per se is not a reasonable endeavor for long-term research because those practices will change over time. Any treatments we impose on the IRS will need to be described in terms of practice (harvest methods, rotation length, etc.), but should be designed to test hypotheses in a more ecological context.

Specific practices/ideas suggested in reviews:

Efficiency of different management prescriptions. Is it more efficient to avoid negative impacts or to ameliorate them once they occur? How do different management practices aimed at improving productivity compare financially? Response of team: Economic efficiency depends on a number of things outside of our control (cost of energy and transportation, markets, labor costs, etc.). The economic factors external to the experimental environment will most likely have a greater influence on economic efficiency than the difference in physical effects of specific practices. What we can do is provide an opportunity to keep track of the cost-components of imposing treatments and the resulting productivity on these sites.

Best mix of maximizing fiber yield and accommodating other resources Response of team: The answer as to how to best accomplish multiple resource objectives is dependent on site specific information and social values. This topic will be part of our discussions at the local level, and may play a role in designing satellite studies.

Fewer, more intense entries versus more frequent, less intense entries. The thought here is that public land management is moving towards more uneven-aged management in part to reduce negative impacts on site. However, uneven-aged management may entail more frequent entries which over the long run could be more detrimental to the site than an even-aged regime. Response of team: Again, to answer this question, a wider design would be necessary than what we could accommodate on the IRS. The number of entries and their intensity is not necessarily dictated by whether or not one is managing under even-aged or uneven-aged regime. The question of continuous site occupancy by "large" trees versus interrupting tree occupancy with a total harvest and regeneration phase will be looked at under the successional pattern series on the IRS.

Current vs "sustainable" practices. Response of team: We don't know if today's practices are sustainable or what would be more sustainable.

Natural vs artificial regeneration; compare site preparation methods. Response of team: See general comments above. Regeneration and site treatment techniques have been investigated in several studies over short periods of time. There may be opportunities through the LTSP Program to continue these investigations for longer periods.

4. CLIMATE Mimic atmospheric deposition on portions of the site. Response of team: Although this might be interesting, we don't see pursuing this kind of investigation at the stand-level. There might be some usefulness in looking at altering inputs on a small-plot basis. We will be monitoring atmospheric inputs to these sites.

Response to climatic cycles (10-100 years). Climatic cycles, including drought and periods of abundant moisture, may have tremendous influence on realized productivity. The influence of climatic cycles may overshadow effects of management. Response of team: We will be monitoring climatic factors on these sites. The team recognizes the importance of collecting climatic data on site.

Effect of global climate change on long-term productivity. Response of team: We hope to link our efforts with the Global Climate Change Research Program. Sharing common sites, information and data protocols will be a start. Part of the influence of climate change will be its influence on presence and abundance of species, which we will be monitoring on all treatments.

5. ROTATION LENGTH Compare short-crop with harvesting at culmination of mean annual increment. Response of team: Effects of rotation length will also depend on the amount of material removed in thinnings and at end of rotations. There may be aspects of this addressed in the treatments designed to manipulate soil organic matter. From a nutrient budget perspective, this sort of question may be more fruitfully pursued with stand projection models.

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Within broad genotype/geographic scale, compare rotation lengths in terms of financial and intrinsic productivity. Response of team: Again, this may be better pursued through modeling. See discussion above on economic efficiency.

6. SUCCESSION Functional aspects of succession and how capturing mortality through harvest may interfere with that. Response of team: A no-harvest, minimal interference treatment is included in the successional pattern series.

Add another uneven-aged treatment to compare one with early successional species to one with late successional species. Response of team: Promoting early successional species in an uneven aged stand may be difficult. We may have flexibility on some sites to add treatment units for stand-level investigation. What is done with those additional units will be determined on a site specific basis.

Role of below ground successional components. Response of team: This will be a major focus within the LTSP Basic Research effort on these sites and in other settings.

7. ECOSYSTEM RESILIENCE TO MAJOR DISTURBANCES Response of team: This concept would be difficult to investigate in an IRS setting. We will be looking at prior disturbance history on the IRS through records, old photographs and retrospective work (e.g., stem analysis). The resilience concept should play a major role in the Global Climate Change Program and we hope to assist in that effort. The IRS Research Plan will also address how major, unplanned disturbances might affect the research and layout possible contingencies.

8. ROLE OF PATHOGENS (heart rot fungi/windthrow; role of mistletoe in stand structure) Response of team: This is a very interesting and pertinent field. Unfortunately, the IRS framework will not enable us to inoculate stands or do manipulative research with regard to pathogens. We do intend to inventory the sites for insects and pathogens prior to treatment and monitor populations throughout the experiment. Role of mistletoe in stand structure will probably be an unavoidable opportunity on east-side sites. We're also beginning to coordinate with the National Forest Health Program.

9. USES OF THE FOREST OTHER THAN TIMBER PRODUCTION MAY BE MORE IMPORTANT IN THE FUTURE. Response of team: We might agree with that statement. However, forest resources all depend on the presence and health of the forest, so any long-term research effort on forest productivity should look directly at the plant component, especially the trees. Within the IRS concept, it makes sense to us to look at primary forest production in a manipulative way and monitor the resources that are more meaningful at a landscape scale (recreation, wildlife, water, air...).

SUGGESTIONS FOR CONDUCTING LONG-TERM RESEARCH

1. IMPORTANT MEASURES OF PRODUCTIVITY AND MECHANISMS TO KEEP TRACK OF:

a. Distribution of biomass over time, including fauna above and below ground. Also including measures that relate to product value (board feet, quantity/quality of habitat)

b. Measures of productivity (or potential) not related to vegetation soil aeration, moisture (including deep soil pore moisture, water balance), and available nutrients

c. Soil enzyme status

d. Autecology

e. Genetic variation within species

f. Some measure of structural/functional diversity

g. Resilience

h. Allocation of carbon by type (e.g., lignin vs sugar)

i. Some measure of human response to application of treatment and results

j. Canopy dynamics.

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k. Conduct ecological unit inventory prior to treatment, describe sites in ways that can put them in broader context and identify scope of inference.

l. Presence or absence of nitrogen fixers or other species that may influence productivity

m. Carrying capacity of the site with regard to resource outputs.

Response of team: All of the above (and more) seem important to keep track of. Funding availability will probably force us to address some of these in less detail than others. Some will be in a category of "opportunities for others to pursue" on these sites (e.g., human response). Our primary emphasis will be on (a.), distribution of plant biomass (quantity and quality, live and dead) over time above and below ground. This budget work will be done at the stand-level. Quantifying soil amount, depth, condition will also receive a lot of attention. The research plan will define these measures, how they will be taken, and how they contribute to analyses.

One reviewer suggested that the ultimate comparison of treatments should happen after year 200. At year 200, one could remove all vegetation, and plant a single species of known genetic makeup across all treatment units and compare growth at designated time intervals. This and other end-point assessments will be explored. Smaller bioassays could be conducted periodically with seedlings or other vegetation either on site or in the lab on soils taken from treatment units during the 200 years.

2. PROBLEMS THAT COULD JEOPARDIZE THE RESEARCH

a. Climate Change: the climate which led to today's forests will not be repeated, nor will the climate of the next 200 years. If climate changes drastically over a short period of time, the species present on the treatment units may not be optimal for the site after all, and may die or attract unwanted pest and disease attention.

Response of team: There's no arguing with either of these statements. However, we can document the climate as we go and link any changes to vegetative and soil response. All in-the-woods research is subject to these concerns, even the growth and yield research that is relied on so heavily for projecting timber supply and planning forest operations. Should climate shift rapidly, having these sites intact with different successional patterns present and monitoring systems in operation, we will be well poised to learn from the shift.

b. Insects, Disease, and Wildfire: Aren't chances pretty good that an outbreak, epidemic, or catastrophic fire will prematurely end the study?

Response of team: That also is a possibility in any study. Even those that are relatively short are subject to this concern because we cannot always tell what happened in the past and what influence those occurences might have on our ability to discern effect of treatment. The research plan will set management direction for handling suppression, etc. Past fire history, insect and disease presence (and history, if available) will be determined on sites prior to treatment unit lay out. Possible contingencies will be set forth in the research plan in case an "episode" should occur. If a wildfire or outbreak comes through and has the same effect on all units, then the research could proceed more or less as is. If certain treatments are consistently effected differently than others, we might be able to figure out why. Should there be random but uneven disturbance, the research team at the time will need to decide whether or not to replicate the disturbance on the non-affected areas.

c. Administrative Neglect (plots harvested or fertilized by accident, roads built through study area, etc., dwindling financial support).

Response of team: Although there is never a fool proof solution to this concern, we will try to avoid such losses through thorough documentation in research and administrative files (Forest Service manual supplement, section in Forest Plans, research work unit descriptions), and through involvement of people in research, in forest management, and outside the Agency to maintain visibility and "ownership" over time. With regard to funding, we are exploring ways of accumulating funds through a foundation to support research on these sites over the long-term (100, 200 years). One of the reasons for chosing the concepts of succession and limiting factors/organic matter thresholds is that these concepts should be

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interesting to a wide variety of people over a long time. We hope to be able to tap "issue" dollars along the way.

d. Multiple pathways of succession: we may not get a consistent mix (species, distribution in time and space) in the replications of individual treatments. How will this affect the research?

Response of team: With regard to tree species, we intend to plant with stock grown from local seed. With respect to grasses, herbs, forbs, and shrubs, if there is a different mix on replicates of the same treatment, we might first want to look at possible reasons (is there a soil or microclimate variable that we did not account for prior to laying out treatment units?). There may be a need to weed, seed or plant non-tree species to maintain continuity.

e. High variability within forest ecosystems: is detection of significant difference between response of treatments possible?

Response of team: Variability, especially with regard to soil properties, has always plagued forest research. Within site variability can cloud any effect of treatment on an average basis. Site productivity may, however, be meaningfully described in terms of pattern rather than averages. We are currently exploring the use of pattern quantification and the different statistical tools available to compare patterns.

f. Can we really separate effects of site (soil status, organic matter distribution, successional sequence) from the influence of age, stocking level, species (genotype) on individual tree growth?

Response of team: A one-time slice would definitely have that problem if the primary interest was in commercial volume. If we are interested in accumulation of carbon over time, this is less of a problem. Controlling and quantifying age, stocking level, and genotypes on these sites might allow us to separate these influences in light of growth and yield research.

3. OTHER IDEAS THAT CAME UP IN REVIEWER'S COMMENTS:

a. There is a gap in the effectiveness and efficiency of practices between those conducted under research settings, those achievable through management prescription given current constraints, and what actually happens in practice. Is there a way to describe, quantify, and/or shorten that gap?

b. There is a need to develop guidelines for new management strategies. Do we need to restrict the number or type of entries? Can we define optimal withdrawal levels and frequencies? Can soil amendments abate pest and pathogen susceptibility? Can artificial regeneration be successful in the presence of mature trees?

These questions are being explored under the Station's New Perspectives Program.

c. There is an opportunity to remeasure site index plots.

Part of the role of the Long-Term Site Productivity Program outside of the IRS will be to keep track of these opportunities, where the documentation is houses and who the primary contacts are. Opportunities will be taken advantage of as funding permits.

d. How does landscape position affect competition and productivity of selected species? (Influence of slope, aspect, elevation, position on slope).

This question is being addressed by some studies unrelated to the LTSP program. Landscape position will be considered in how treatment units are laid out and blocked.

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