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Evolution of Mensuration Arney – June 30, 2009

Evolution of Forest Mensuration in the West Where have we come? Where are we? Where to from here?

James D. Arney, Ph.D.1

Abstract

This paper presents a chronology of the evolution of forest mensuration in the western States in the last half of the 20th century. The significant turning points were the result of a mixture of people, technology and changing direction of the forest industry. The intensity increased and evolved from general principles of forest management to site-specific prescriptions requiring precise timing of events. The result of increased intensity of research and development in the last decades of the 20th century was an unexpected decline in long-term commitments to ongoing research in the 21st century. This paper brings together many of the factors contributing to this evolution in forest mensuration with a view to some possible future scenarios. Introduction

Somehow the forest industry has arrived in the 21st century with a multitude of questions about what kind of forest management to practice and what are the impacts of alternative forest management practices on society. The U.S. National Forests are now characterized as reservoirs of carbon, water, wildlife and spirit. These are popular characterizations and are commonly believed to be too complex to understand. It is also popular to believe that nature knows best and humans are not part of that universe. The USFS approach to forest management has evolved into a program of stabilizing all forests as broadly-spaced, residual old trees with a minimum of understory vegetation. The objective is low exposure to fire and insect attacks with little consideration about future growth capacity. Where will this popular view lead forest tenure and management? More specifically, what analytical methods to we have available to us to evaluate the status of our forests and to forecast the alternative outcomes of different forest management strategies? Do we have tools, insights or results from the last fifty years of forestry research and development? There are those who believe that all of these problems are new and that they require new approaches and skills. On that note, let’s remember that forest management practices have been researched, developed, exercised and taught in the West for well over fifty years. When a forester walks into a forest in 2009, what is observed now relative to what was observed in 1959 (fifty years ago)? What means are now available to that forester to assess the health and status of that forest? What other professional support (methods, tools, research and experience) is available to make those assessments?

1 Submitted 2009-June-30, Final 2009-September-04. Senior Biometrician, Forest Biometrics Research Institute, Philomath, Oregon.


It should become apparent in reading this article that there exists a wealth of research, tools, methods and practices that have been developed for assessing our forest resource. However, the current practice of our profession may be leading us to believe this background is not relevant. In addition, it is important to note that this review is not about any individual person or organization. It is simply a review of what has transpired in our recent past with a view of the future. Where have we come?

Let’s start with a foundation reference to the USDA Technical Bulletin No. 201 published in 1930 (revised 1949) by Richard E. McArdle and Walter H. Meyer. This Bulletin describes the “Yield of Douglas Fir in the Pacific Northwest” with tables and charts. These yields were for “normal” stands with variation due only to site and age. They did not reckon with variation in yield due to silvicultural treatment, species composition, stocking, defect or utilization practice. Site capacity was indexed on total height achieved at a stand age of 100 years. Forest mensuration includes balancing and integrating technologies in inventory, yield forecasting and harvest scheduling. Each component is dependent on the evolution of technologies in the other components. This is a key factor to understanding mensuration. During the 1950’s large tracts of forest ownership were cruised to obtain estimates of the standing volume in commercial timber species. Only trees greater than 11 inches were recorded. Western Hemlock, Red Alder and most secondary species were considered weeds regardless of size. Cruises were compiled on a 40-acre basis across each Section of a Township. Paper maps were then produced with color coding for different age, size and volume levels per acre. These cruises were typically strip cruises one chain wide with breaks every five chains to constitute a plot. One transect was run for each 40-acre block with four transects per Section. This constituted a five percent cruise. Most commercial species larger than 8-inches in diameter were tallied by the 1960s. In the late 1950’s and early 1960’s Bitterlich (1939) angle gauge became popular especially when Grosenbaugh (1952, 1958) expanded on this approach with labels of “Plot-less timber estimates” and “Point sampling”. Forest harvest planning also began to take hold in the 1960’s. It was targeted on the “total” forest resource and the “proportion” of that resource that could be harvested annually without degradation. Little detail was known about the magnitude and character of the forest resource at that time. In addition, analytical tools to process forest inventories were not available or previously known. Harvest levels were computed from simple formulae, such as the Hanzlik formula, the Austrian formula and the Kemp formula.


“An important maxim of forestry is the management of forest lands for a continuous,

controlled flow of timber. The key to achieving sustained yield is to establish a

regulated forest with the proper distribution of stand age and size classes so that

approximately equal periodic harvests of the desired size and quality are produced.

Usually the forester is not so fortunate as to start management on a forest with a

regular stand distribution. To achieve the desired distribution, he must often liquidate

large tracts of old-growth virgin timber, reforest un-stocked and under-stocked lands,

and thin or harvest stands of intermediate-age classes. These management operations

transform or convert the irregular forest structure to the regulated one.” (Hennes, Irving & Navon, 1971)

These formulae were used to compute harvest levels from existing inventories with estimates of future volume coming from hand lookup of Bulletin #201 yield tables. The inventories were summarized into site classes and age classes to assign yields from the yield table. Total acres in each site-class by age-class cell were the most important factors affecting the calculation of the future harvest capacity over time. The classes were fixed while acres were shifted from one stratum to another as acres were harvested and grown to the next age class. This yield table lookup helped clarify the observation by many foresters that the young forests which they were managing appeared to grow at rates different than the yield tables. In fact, it became readily apparent that thinning an over-dense stand would significantly improve its growth rates to achieve some target tree size. This prompted George Staebler and Dick Williamson (1954) to launch field trials to test various levels of thinning intensities and timings for their resulting impact on harvest age volumes. Others were also interested in these questions and yield potentials. This led Weyerhaeuser Company to hire George Staebler as their forestry research director. His mission was to lead broad investigations into the dynamics of young forests and their associated yield capacities under management. Staebler lead the development of the “Target Forest” silvicultural treatment regime. This regime concept later became the “High Yield Forest”; which was publically and robustly promoted by Weyerhaeuser over the next four decades. It was in this same period of time that Jim Girard identified that these trees growing in various densities resulted in different taper and volume. He went on to develop a cruising technique wherein an additional diameter measurement at 16 or 32-foot height on the tree could provide a more precise estimate of standing volume. After cruising stands of all species over much of the Pacific and Inland Northwest, Jim Girard and Don Bruce (1963) produced a set of Form Class tables (16-foot and 32-foot) for estimating Scribner board foot volume given diameter at breast height, form class and tree height in numbers of logs. This approach was taken up almost immediately by almost all other company timber cruisers. Meanwhile, Gerry Hoyer and Gene Little from the Washington Department of Natural Resources were recognizing the same variation in tree volume of cruised stands. Together with Ken Turnbull (then Instructor of Forest Mensuration at the University of


Washington), they developed the Washington State Tarif Tables (1963). These tables accomplished the same result as Jim Girard’s form class tables with the additional ability to identify the volume of any tree in the stand by Dbh alone, once a Tarif number was assigned to the stand. Interestingly, these two approaches could be applied to individual trees by assigning a form class or tarif number to each measured tree and then deriving the amount of volume by tree. Instead, most cruise compiling methods were set up to initially assign a single form class or tarif number to each stand, then derive volumes of all trees using the same index. This actually lost some of the potential precision that could have been gained using either of these approaches, but the computations by tree seemed too cumbersome. In fact, Don Bruce made the comment on the last page of their form class table handbook that it would be “easy to write a single equation giving the volume for trees of any height. Such an equation is cumbersome in use, and apparently of no practical value.” Others like Lew Grosenbaugh (1954) began investigating tree taper and volume with the result that whole tree taper profiles became of significant interest. His research paper on height accumulation in steps of diameter instead of height provided Arney (1972) with the insight to apply a 4-power rifle scope to Bitterlich’s Spegiel Relaskop ( ) to measure upper stem taper profiles and volume. Later Walter Bitterlich produced a compact tele-releskop which he was not able to patent in the United States due to Arney’s previous work. This is the second example of many where different researchers were tackling the same problems (and opportunities) at the same time and then arriving at similar ends. The first example was form class tables and tarif tables. The observation that stands could grow at a wide range of different rates became both an opportunity and a problem. The conventional lookup of yield capacity by site and age class in Bulletin #201 was not as definitive as previously expected. Both species composition and differences in silvicultural history of an existing stand were major reasons for departures from the USDA Bulletin #201 yield tables. This resulted in two major developments with implications still being realized: 1) The first was an aggressive and region-wide expansion of research by the U.S. Forest

Service Pacific Northwest (PNW) Forest and Range Experiment Station into the long-term effects of initial tree spacing of new stands and thinning of existing stands. Experimental Forests were established opportunistically in various locations throughout Washington and Oregon. Research field trials were established in these Experimental Forests to evaluate growth and yield under varying levels and timing of silvicultural treatments. One cooperative study across many ownerships in the West was the Cooperative Levels-of-Growing Stock (LOGS) Study. These trials were established from Campbell River, British Columbia to Roseburg, Oregon on Federal, Provincial, State and private ownerships. Many USDA Research Papers and Research Notes have been generated from progress on these field trials.

2) The second development was establishment of a systematic grid of Continuous Forest Inventory (CFI) plots on many ownerships in the West. These permanent plots provided both a measure of standing volume and an estimate of current growth rates


on each plot. This growth estimate included observations of individual species, size, density and defect factors imbedded in the forecasted growth capacity. Owners of the mixed species forests of the Inland Northwest found this type of inventory to be much more useful for forest harvest planning than the standard lookup table approach popular in the Douglas-fir forests of Coastal British Columbia, Western Washington and Western Oregon. Many timber companies (e.g., Boise Cascade) and BIA Reservations found this CFI method to be very useful for establishing future harvest levels when combined with the Austrian formula. This approach is still the mandated method of harvest planning by the USDI Bureau of Indian Affairs in Portland, Oregon, for all Native American reservations under their administration.

The CFI database provided species composition, size and density for each permanent plot. The density of permanent plots across the ownership provided the number of acres which each permanent plot represented. For example: Non-Federal lands – Forest Survey 3.4-mile grid 7,398.4 acres/plot Federal Forest lands 1.7-mile grid 1,849.6 acres/plot Large Industrial Forest Ownership 0.25-mile grid 160.0 acres/plot This CFI method is still in use in 2009 on a few ownerships, primarily native reservations managed by the USDI Bureau of Indian Affairs. It was also the foundation technology for the USDA Forest Survey across all non-federal lands in the United States. This later evolved into the USDA Forest Inventory and Assessment program with essentially the same technology base. The primary goal is past growth and current status of the forest. Like Weyerhaeuser owners, others with large tracts (500,000 acres or more) realized that there was something to learn about silviculturally managing the dynamics of the young forest. Staffing of USFS Experiment Stations increased, field stations were established, the British Columbia Ministry of Forests established the Research Branch and Inventory Branch, the Canadian Forestry Service established the Pacific Forest Research Center in Victoria, and a number of private companies developed their own internal forestry research groups (MacMillan-Bloedel, Weyerhaeuser, Crown Zellerbach and Potlatch). Lots of good will and cooperation was exchanged in these years as demonstrated by Weyerhaeuser publishing the 50-year Douglas-fir Site Index report by King (1966). This report from a private company became the second (compared to Bulletin #201) most quoted forestry publication in the West. It also recognized that forest stands were likely to be harvested before reaching a total age of 100 years and a younger reference point was needed. By the mid 1970’s, Staebler had developed a leading forestry research team unparalleled anywhere in North America with nearly 100 professional forest scientists in silviculture, nursery practice, growth & yield, watershed, wildlife and genetic research programs. The organization became a reference point for intensive forest management. By 1970 other industrial forest owners became interested in pursuing research into more aggressive forestry practices. The USFS Experiment Stations and BCFS Research Branch were active in thinning and spacing field trials; but the industry desired to expand into fertilization, soil nutrition, nursery practices and non-tree vegetation control in new plantations. The regional forestry schools were identified as logical host institutions for a


new type of research organization – the research cooperative. This structure provided forest ownerships, too small to establish their own research teams, the opportunity to play an active role in prioritizing and funding forestry research of direct and applied interest to their own forests. It also provided a means to share investment in research without disclosing proprietary forest information between owners. The forestry schools gained additional funding by sponsoring these research cooperatives and the US Forest Service found popular support for their research through broad combinations of collaboration and team projects. The early 1970’s also brought on the expanded opportunities of computer processing. Forest resources cover large acreages of landscape encompassing wide variations in topography, soils, species composition, age classes and stand densities. Almost every aspect of developing an inventory, projecting future yield and determining a harvest level required laborious and time-consuming calculations. These calculations were complicated by layers of statistical inferences due to the nature of measuring the forest through varying sampling designs on many subsets of the total landscape. This new computer processing capacity expanded forestry research into a new direction – computer-based models for growth projection and harvest planning. The traditional Austrian formula and others were quickly replaced with Timber RAM, TREES and FORPLAN harvest scheduling computer models (among others). It became possible to evaluate alternative silvicultural investment strategies, species compositions and management intensities in addition to traditional ranges of site class and age class acreage distributions over time. These types of research investigations were more demanding of available computer resources than from access to an Experimental Forest. Thus, the university forestry school became the default host to launching new approaches to forest harvest planning. This also facilitated changes in the Federal and Provincial research organizations to establish new teams investigating and applying computer-based forest planning systems. Private industry paralleled these developments with groups labeled as “Operations Research” at their corporate offices where these new computer planning models were put to work. Significant investment and research in field trials had evolved by 1972. This contributed to the opinion that computerized yield tables were now the weak link in the (inventory, growth and planning) infrastructure of forest management. There were ample numbers of permanent-plot field trials that had been established over the past 5 – 10 years to document stand volumes at various ages and densities on most sites in the Northwest. These field trials provided Chuck Chambers and Frank Wilson (1972) with 356 permanent plots to build regression models to predict Douglas-fir stand volume from site index, stand age and stand basal area per acre. Later in the same year they also published yield predictions for Western Hemlock using the same input parameters on 232 permanent plots. Both of these yield projection reports included applications of the tarif system from Turnbull et al (1963) to derive board-foot volume. Now the forest planner had an inventory basis of total acres by site and age, regression models to project those inventories forward in time; and, a computerized harvest planning


system to schedule the harvest level and capacity of their ownership. Forest management planning became dynamic with these analytic tools available. Each year it was now possible to reduce the total inventory for actual harvest removals for that year and then re-run the harvest capacity analysis on the whole ownership. Forest managers could begin to visualize a working forest over time, its species composition and stocking levels under various kinds and intensities of forest management. In this environment of dynamic forest management options, observations of thinning and fertilizer effects and unprecedented computer analytical capacity, the expansion of research into forest simulation (growth & yield) models began. In 1969 with financial support from the computer service center at Oregon State University, Jim Arney (1971) began building a tree and stand growth simulator for Douglas-fir that could invoke multiple thinning and fertilization treatments through time. This simulator could emulate any number of trees per acre on any site index level. Using King’s (1966) site curves and Grosenbaugh’s (1954) height-accumulation tree volume methods, he could forecast total stand volume in cubic and board-foot volume for any time in the future up to approximately eighty years of age. Crown Zellerbach was already investigating similar computerized growth models (Lin, 1970) and provided permanent plot data and advice to assist in Arney’s developmental efforts. Also in early 1972, the Canadian Forestry Service (CFS) held a meeting at the Petawawa Forest Experiment Station in Ontario of forest mensurationists from across Canada to discuss the tree growth simulation program within the CFS (Honer, 1972). A six-member working group (Brian Armitage, Jim Arney, Imre Bella, Jim Cayford, Frank Hegyi and Terry Honer) was appointed to develop recommendations for tree growth simulation research within the CFS (Honer, 1973). Their report includes the following statements:

“If the extensive forest management practices in Canada were to continue, yield table

methods would probably provide results significant for planning purposes; however, if

we assume that forest management will intensify in the future, we will need methods

that can used to forecast the outcome of a range of alternative silvicultural strategies.

The impact on tree and stand growth of spacing, density, site, defoliation, and

fertilization will have to be considered. Finding solutions to these problems through

thinning, spacing and fertilization studies, and then fitting this fragmented information

together cannot be done effectively with the framework of yield tables.”

“… we need a new kind of framework, a model, that is complex enough to combine

and integrate the effects of all these factors. What is required is an operational tree

growth simulator capable of providing yield estimates for natural and managed forest

stands.”

These recommendations were accepted by the Programs Operations Directorate (CFS) early in 1973, and a program of testing and evaluating was initiated the same year at the Pacific Forest Research Centre (Victoria, BC), the Forest Management Institute (Ontario) and the Great Lakes Forest Research Centre on Douglas-fir, White Spruce and Jack Pine, respectively.


Arney sent a personal letter in summer of 1972 to mensurationists in the West with the following invitation:

“Because there is a high level of interest among mensurationists, an informal

workshop will be convened on September 6 and 7, 1972 at the U.S. Forest Service,

Forest Sciences Laboratory near Olympia, Washington. Interested Mensurationists

are invited to participate. No formal papers will be presented so that maximum

advantage can be taken of this opportunity to discuss common problems and evaluate

various approaches to tree growth modeling. Enclosed is a list of scientists who have

expressed an interest to participate.”

Everyone on the list accepted the invitation. The participant list is of historical interest: Weyerhaeuser Research Centralia, WA Dave Bower, Dave Lewis, Jim

Woodman, Dale Shaw Crown Zellerbach Research Camas, WA Bob Strand, Jim Lin MacMillan-Bloedel Nanaimo, BC Don Reimer PNW Forest Expt. Station Olympia, WA Dick Miller, Don Reukema, Dick

Williamson, Bob Curtis, Dave Bruce, Don DeMars

Depart. Natural Resources Olympia, WA Gerry Hoyer Faculty of Forestry, UBC Vancouver, BC Don Monro Canadian Forestry Research Victoria, BC Jim Arney, Jim Lee INT Forest Expt. Station Moscow, ID Al Stage Rocky Mt. For. Expt. Sta. Fort Collins, CO Cliff Myers NE Forest Expt. Station Columbus, OH Sam Gingrich PSW Forest Expt. Station Berkeley, CA Dave Sharpnack PNW Silviculture Lab Bend, OR Walt Dahms, Jim Barrett BC Forest Service Victoria, BC Al Fraser, Nick Kovac Within two years an informal correspondence among a wide geographic array of growth modelers developed. This correspondence was mostly by personal letter or phone conversation among modelers. The correspondence grew to include Al Ek (Wisconsin), Lee Wensel (California) and Harold Burkhart (Virginia). The discussions and comments were highly technical and dedicated to specific model building questions and alternatives. This was a new science and there was ample room to share ideas without treading on anyone else’s developmental efforts. As a result, almost none of this is documented in the retrievable literature. Building on this series of correspondence, various forest modelers began documenting their progress. Ken Mitchell (1973) began developing the Tree and Stand Simulator (TASS) at the Research Branch of the British Columbia Ministry of Forests in Victoria. Al Stage (1975) began building the Prognosis growth model at the Intermountain Forest Experiment Station in Moscow, Idaho. Lee Wensel (1977) established a redwood growth and yield cooperative among Northern California forest land owners to build the CRYPTOS and CACTOS growth models. Al Ek and Rolfe Leary (1975) developed the STEMS growth model in the Lake States Experiment


Station. Each of these modelers was in contact with the others and aware of the relative success and approaches being attempted elsewhere. There were actual pieces of Fortran source code sent among modelers where similar problems were encountered and someone found an efficient solution. A IUFRO Meeting was held in August, 1973, in Vancouver, British Columbia. At this meeting Don Monro (1973) presented his paper on structure and approaches to growth and yield models. His group labels used to identify types of growth models are still used 35 years later (i.e., Whole-stand; Tree-list, distant-independent; Tree-list, distant-dependent). Each of these growth and yield simulators handled individual tree lists containing at least diameter at breast height, total height and the number of trees per acre represented by the tree in the list. The growth projection would cycle through a number of periods resulting in diameter increment, height increment and mortality rates which would differ by varying degrees and kinds of species, site, silviculture, size and stocking conditions. These growth models provided extensive versatility to the inputs for the forest harvest planning models. This functionality became an immediate priority to many forestry companies to incorporate into their internal inventory designs, methods and planning analyses. Perhaps it is not surprising that in 1973 Weyerhaeuser Director George Staebler and USFS Research Station Director Bob Buckman decided to co-host the development of a new managed-stand growth model for Douglas-fir in the Pacific Northwest. Staebler also wished to verify the yield projections for their internal “Target Forest” numerical thinning and fertilization tables. Staebler hired Jim Arney to join with Bob Curtis (USFS) as co-leaders of a two-year project to develop this new growth model. The cooperative project was announced in the Seattle Post Intelligencer and Portland Oregonian in October 1973. The first action by Arney and Curtis was to enlist the participation of other organizations with permanent plot research trials established for four or more years. None of these field installations had been shared outside of their host organizations in the past. The invitation to participate was accepted by fourteen federal, state, provincial and private forestry organizations. This created the most extensive database ever combined in one yield development analysis in the West. The geographic range was west of the Cascade Mountains from Medford, Oregon to Campbell River, British Columbia. Interest in retiring Bulletin #201 for a managed-stand growth & yield model was high. Stand dynamics through thinning and fertilization was apparent in field observations. A tree-list growth model capable of forecasting these silvicultural effects was highly desired. Inventory methods and harvest planning technologies were being redesigned and developed to take advantage of this more complex and flexible yield forecasting structure. Each of these developments in the 1960s and early 1970s cycled back into the inventory methods both in the cruising designs and information retrieval. Since the growth models


were requiring tree lists of diameter, height and numbers of trees per acre, then the cruise design began to collect diameter at breast height in addition to tree count on a point sample that previously only required a tree count to determine an estimate of total basal area per acre. This provided stand structure detail for silvicultural regime building. In the 1970s, point sample cruises began recording all trees (all commercial species) to the nearest 1-inch which were greater than 5-inches diameter at breast height. This provided a more complete estimate of the diameter distribution found in each cruised stand. Meanwhile, ownerships with interest in moving forward into new silvicultural regimes of young stands quickly noted limitations in their CFI approach to inventory. It provided good information about past silvicultural treatments; but it provided no basis for evaluating future regimes. In the early 1970s and 1980s, these ownerships switched to more intensive temporary plot designs with fixed-area sub-plots for small trees (less than 5-inches diameter); crown ratio, upper-stem taper, tree age and tree damage measurements. This degree of measurement intensity provided detail about species composition, log size distributions, total basal area and stand height/age indices to site index classification. The permanent plot inventory grid was replaced with a stand-based sample of temporary plots. However, the size of the database required to handle this detail for each stand in the inventory became a concern. This brought on the development of diameter distribution functions to estimate the size and number of trees in a stand given only a few parameters. The Weibull function (Bailey and Dell, 1973) was the most popular method of generating diameter distributions. It used only the number of trees per acre and average diameter of the stand to generate normal distributions of trees. This allowed for much smaller demands on the size of inventory databases for an entire ownership. As interest evolved into higher resolution inventory methods, so did the database structures and database handling methods. Initially in the early 1970s most ownerships were obtaining an aerial photo coverage of their forested lands on a periodic basis. This aerial photo coverage was then “photo-typed” into polygons of 10 to 200 acres in size with labels identifying the species, size and density of that polygon. Typically, these were not more than 4 to 6 species groups, 4 size classes (seedling, pole, small saw and large saw), and 3 density classes (poor, medium, well-stocked). A single interpreter would classify an entire ownership and transfer these polygons and labels to an inventory map in a matter of a few weeks. This map became the new inventory base with acreage computed for each polygon. In 1970 this inventory map was used in conjunction with field-cruised information to assign average volume to each “photo-type” label. As the computer capacity expanded during the 1970s, the map was replaced with a computer database where the acreage and volume could be stored for each polygon. Initially only the acreage changed from polygon to polygon within a common label since all field cruise plots were being


combined within each stratum (species, size, stocking) prior to compiling the volume estimates. There was only one volume level per stratum within each ownership. By 1975 more aggressive organizations began tracking the cruise plots from individual polygons (stands) in order to compile each polygon with observations only from that polygon. This provided the forester with much more confidence that what was contained in the inventory database could be actually found in the field. By late 1970s, average volume by “photo-type” label was quickly becoming recognized as not sufficiently precise when the forester went to the field to develop silvicultural plans. This began the transition from one volume class per stratum to a combination of individual compiled volumes per stratum for cruised stands with an average volume per stratum for the remaining un-cruised stands within each stratum. In the late 1970s there was typically about 10 to 25 percent of the acreage in each stratum which was cruised and recorded as individual volumes by stand polygon. The remaining 75 to 90 percent of the acreage in those strata were characterized with the average volume found from the cruised stands within each stratum. The next year additional un-cruised stands were cruised, compiled and recorded. This caused a continuation of the transition to almost every stand (polygon) within a stratum being cruised at least once by the early 1990s. This transition occurred over about twenty years (1975 – 1995). By the mid 1990s most forest ownerships were maintaining inventory databases which contained eighty percent or greater cruised acreages among all stands and strata. These stand-based inventories were being recognized as much more robust and site-specific for forest planning and management. The typical application was to directly cruise each stand (polygon), compile it and load the forest inventory database. The remaining un-cruised stands could then be updated with the weighted-by-acres average of all cruised stands within each stratum. These remaining un-cruised stands were gradually becoming a smaller and smaller subset of each stratum as the years progressed. This progression to a much higher proportion of the forest inventory with direct field measurements resulted in a significant decline in the number of contracted projects for aerial photo-classification and mapping by the mid 1990s. It was common practice in the 1970s to fly a complete set of aerial photography to generate a timber-type photo classification. This was the standard approach to develop a forest-wide inventory. However, once the complete photo-type coverage was available, the inventory forester began cruising stands to convert from a dependence on photo-type labels to a directly measured stand-by-stand forest inventory. The era of aerial and satellite vegetation mapping for forest resources began and ended in a matter of twenty years (1970 – 1990). It is interesting to note the departure that began to emerge between forest practices on federal forests versus private forests in the 1980s and 1990s. Satellite imagery for vegetation mapping became commercially available in the late 1980s creating significant interest for potential applications on federal forests. The LandSat 30-meter pixel vegetation mapping capabilities appeared to provide a high resolution solution for forest mapping of federal forests. Region Six of the US Forest Service embarked on vegetation mapping of all 19 national forests (23 million acres). The satellite solution to forest


mapping got confounded with a plan to expand the standard aerial photo timber-type methodology to a much higher number of levels for each stratification factor. The traditional aerial photo classification (4 species groups / 4 size classes / 3 stocking levels) with a minimum polygon of 5-10 acres was replaced. The new satellite-based classification became 20 species groups / 7 size classes / 5 stocking classes / 3 structure classes with a minimum polygon size of one acre. The maximum 48-class stratification was expanded to 2,100 potential classes. This solution was applied to all federal forests in Regions Six and Five. The difficulty was that it was not repeatable on the next pass of the satellite. The entire vegetation mapping of these national forests never resulted in a working forest inventory. As late as 2009, federal and university forest researchers are still trying to discover forest inventory by using remote sensing. It has evolved to exploratory projects involving concepts such as most-likely neighbor and LIDAR point-density clouds. These may be classed as technological solutions which are attempting to find the appropriate problem. They will keep these researchers occupied for a significant time to come. The technologies are interesting, but the status of forest inventory has evolved well past remote sensing on most private forest ownerships. The decade, 1970 to 1980, was also the period where emphasis in site productivity became significant. The Washington Department of Natural Resources initiated the Forest Land Grading Soil/Site stratification project throughout Washington. Forestry organizations were now assigning a unique site index to each polygon in their inventory. The developments in computers, inventory methods and growth model methods could provide capacity for projections of silvicultural treatments from cruised stands containing unique site, species and stocking details. The forest inventory was now a stand-based inventory with unique information for each stand becoming stronger with each passing year. The opportunity to project this inventory for forest harvest scheduling was becoming a reality due to developments in both growth modeling and harvest scheduling technologies. Meanwhile the two-year Weyerhaeuser-USFS managed-stand growth model development project was moving slowly. It took two years just to gather all 2,169 contributed research plots (252 installations, 17,042 measurements) into a common database structure and complete edits to verify data quality and adequate detail in measurements and treatments. A research database standards committee was formed and a detailed resolution was submitted to and accepted by the Western Forestry & Conservation Association for standardization of all coding conventions for forestry research field trials and databases. The committee was known as COSMADS (Committee on Standard Measurements and Database Structures). It became the basis for research databases by most forestry organizations over the next thirty years (Curtis, 1980). Under Rod Meade, Weyerhaeuser Research Field Supervisor, with Jim Arney and a field crew of up to eight, over 70 percent of these field trials were visited, re-measured, back-dated and stem-mapped in 1974-75. Individual-tree stem maps were developed on at least one replicate of each treatment in each installation (38% of all plots). This one crew traveled from Nanaimo, British Columbia to Roseburg, Oregon standardizing all datasets


for quality and completeness of detail for measurements and treatment history. This level of commitment, investment and consistency of detail had not been seen before or since. Increased resolution of inventory designs and expanding computer processing capabilities helped focus the direction and priority of this “Managed Stand Yields of Douglas-fir” project. Prior to the 1970s, a yield forecast was adequate if age, site index and stand density were specified as input parameters. By 1973, it was expected that the forest manager would be able to forecast the effects of silvicultural regimes on yield projections. These projections would be sensitive to log size assortments from thinning and final harvest volumes and be arrayed in log dimensions for value assessment. Many organizations were already developing inventory systems with greater resolution in species composition, stand structure and site productivity characterization. The intensity of these activities was demonstrated by three separate national meetings on inventory design in 1977 (i.e., Colorado, Georgia, and Arizona). Technological developments in forest inventory, growth modeling and harvest planning were building on new developments in each of these other disciplines almost as they were being discovered. In this setting, Curtis elected to limit his involvement in the cooperative yield project to only a stand-average projection methodology. Having never developed a dynamic growth model, his level of comfort was closer to the methodology provided by Chambers and Wilson in 1972. Therefore, two modeling approaches were underway in the Weyerhaeuser-USFS project – a whole-stand model and a tree-list, distance-dependent tree model. In January 1978, Arney produced a 104-page draft report2 titled, “Managed Stand Yields of Douglas-fir in the Pacific Northwest”. It remained on hold while Curtis pursued the whole-stand model. Many organizations attempted to gain access to these results through 1977 to 1980 without success3. By mid-1978, both George Staebler and Bob Buckman were no longer Directors overseeing this project. Connor Boyd and Bob Tarrant, respectively, became the new research directors in Weyerhaeuser and the Pacific Northwest Forest and Range Experiment Station. A letter went out to all participating organizations from Weyerhaeuser with signatures from both Directors on September 18, 1979 stating that the “Weyerhaeuser analysis had been terminated” and that the “U.S. Forest Service results will become the final output of this cooperative effort.” Arney became aware of this conclusion on October 25, 19794. This was not the grand cooperative project which Staebler had visualized when he initiated it in 1973. All other contributors were left without a tree-list growth model to link to their newly evolving inventory systems. Inter-agency policy came into conflict with inter-agency research cooperation. Forest Service managers were not aware of the magnitude of change which had occurred in just six years (1973 – 1979) in forest inventory and planning methods. USDA Region Six forest management planning was still using yield tables while forest industry had completely evolved into tree-list growth models linked to stand-based inventories. The US Forest Service began evolving at a much slower technological pace

2 Personal correspondence. Robert O. Curtis. August 17, 1978. Subject: E17 – Douglas-fir yield tables. 3 Personal correspondence. B. Bond Starker. November 30, 1978. Starker Forests, Inc.; and,

Alan Vyse. February 21, 1978. Ministry of Forests. Williams Lake, B.C. 4 Personal correspondence. R. F. Strand. Research Director, October 25, 1979. Crown Zellerbach Corp.


during that period. Its methods in 2009 still remain significantly behind the technological developments and applications in forest mensuration on private forests. In April 1980, Arney joined Reid, Collins & Associates in Vancouver, British Columbia to expand their capacity in growth and yield modeling, computer simulation techniques and computer-assisted mapping. Once established, Arney set up an independent data sharing agreement5 with the U.S. Pacific Northwest Forest and Range Experiment Station to gain access to the database developed for the “Cooperative Douglas-fir Yield Study”. The full analysis of a tree-list growth model was repeated from these data and distributed as the Stand Projection System (SPS). It included managed stand projections and inventory updates for Douglas-fir, Western Hemlock, Western Red Cedar, Noble Fir and Red Alder. Tree volumes for any merchandizing limits were determined using Demaerschalk and Kozak’s (1977) whole bole taper equations. SPS was distributed including the growth model, a user’s guide, documentation and Fortran source code for $235 (Arney, 1985a). Over 140 copies were distributed in the next four years (Arney, 1985b). A reasonable degree of inter-agency cooperation was re-established. In 1981, Robert O. Curtis, Gary W. Clendenen and Donald J. DeMars distributed the U.S. Pacific Northwest Forest and Range Experiment Station growth model, DFSIM. It would only grow Douglas-fir in pure stands without a tree list input or output capability or capacity to modify the volume merchantability specifications. It was not designed to meet the needs of the new forest inventory database structures put in place in the late 1970s. However, in 1982, William R. Wykoff, Nick L. Crookston and Albert R. Stage produced the “User’s Guide to the Stand Prognosis Model” (a tree-list growth model) including multiple species and merchantability options which could be used to update an inventory and produce long-term forecasts. Al Stage had participated in the “Growth Model Workshop” in 1972 and then went back to the Intermountain Forest Research Laboratory in Moscow, Idaho to launch a new project in growth models for the North Idaho region. This later became the Forest Vegetation Simulator (FVS) at Fort Collins, Colorado and the foundation of all U.S. Forest Service growth models nation-wide. Over the developmental years of growth modeling, Al Stage was very adept at identifying useful technologies and sources of funding for his program. It quickly grew to a budget and staff level far greater than anything in the Pacific Northwest or Pacific Southwest Experiment Stations, even though the timber resource value in each of these latter two Regions exceeded that of the Intermountain Region significantly. A disturbing trend became prominent in the early 1980s. As these new growth models became published, public funding began to decline. This was partly due to a declining national economy, but primarily due to the U.S. Congress identifying that forestry growth and yield research was a “mature” science requiring less funding than previously supported. The number of field research trials being re-measured on a regular basis dropped off to less than 30 percent of previous years. The US Pacific Northwest Forest and Range Experiment Station closed the Bend Silviculture Laboratory in 1996 and

5 Personal correspondence. Barbara R. Hague. July 27, 1981. Assistant Director, US Forest Service. PNW Experiment Station. Collection Agreement PNW-81-139.


dropped all support for ongoing research in Ponderosa Pine and associated types east of the Cascade Mountains. Operating budgets for the PNW, PSW and Intermountain Experiment Stations dropped to nearly zero. By 1998 only salaries for existing scientists remained. By 1990, commitment to internal forestry research organizations in Weyerhaeuser, MacMillan Bloedel and Crown Zellerbach dropped to less than one-quarter of funding levels of the 1970s. However, the need for growth and yield research linked to inventory methods and planning activities within each of the private forestry companies was becoming more visible, anticipated and integrated. This situation of increased mensurational technology requirements from forest management organizations combined with declining federal support for research opened an avenue of research development not expected – the private research consultant. The personal computer and cooperative sharing of research databases provided a basis to launch applied research and development from a new perspective. Goals and timetables could be agreed upon prior to implementation of the project. Ongoing support was established and total costs were defined. The foundation of success was an agreed level of commitment, integrity and knowledge among all cooperators. In 1986, Arney conducted a one-year cooperative agreement for analysis of the growth and yield of Western Hemlock using the SPS tree-list architecture. Organizations participating in that project included: Boise Cascade Corporation British Columbia Ministry of Forests CIP, Incorporated Crown Zellerbach Corporation Georgia Pacific Corporation ITT Rayonier Corporation MacMillan Bloedel, Ltd. Oregon Department of Forestry Plum Creek Timber Company Simpson Timber Company USDI Bureau of Land Management U.S. Forest Service, PNW Station University of Washington, Regional Forest Nutrient Research Project Washington Department of Natural Resources Weyerhaeuser Company A range of other SPS analyses were conducted, including Growth Models for Alberta (1991) and Yields for Hawaii (1988). By the early 1980s, most private ownership forest inventories were structured as stand-based polygons within a computerized database. Each stand was identified with unique acreage, site index, silvicultural history and spatial location. Inventory updates came from temporary plot sample designs within an annual subset of stand polygons across the range of vegetation types found on each forest. Cruises from previous years were being updated to the current inventory year in most forest management organizations by using


the tree-list growth models – primarily SPS, Prognosis and some internally-developed proprietary models. Un-cruised stand polygons were estimated from weighted-by-acres average tree lists from cruised stands within the same photo-type classification of species, size and stocking. A mentioned earlier, most inventories evolved over the 1980s and 1990s from approximately fifteen percent of all acres cruised to approximately seventy percent of all acres cruised at least once. This in-place inventory design (and sampling intensity) integrated with a tree-list growth model became a very powerful and defensible basis for long-term planning. Another private research consultant, Dr. Kim Iles (2002), provided further intensive development and continuing education opportunities (with Dr. John Bell, Lou Alexander and Norm Marsh) in forest inventory methods and practices. These developments evolved at a pace well beyond the technology being offered from the traditional university and federal research organizations, perhaps as a result of the change in focus of those research structures. By the early 2000s, almost all new technologies in forest inventory and growth projection techniques were coming from non-traditional sources. A similar trend in technological development was happening in forest harvest scheduling methods. In the 1960’s and 1970’s, it was the total amount of wood resources on a sustained flow that was the concern. Constraints had to do with the kind of silvicultural regimes that would be applied to various site productivity classes and species mixes of stands. In response to these kinds of needs a great amount of effort went into developing various linear programming models such as Timber RAM (Navon, 1971), MaxMillion (Clutter, 1968) and MUSYC (Johnson & Jones, 1979). In the 1980’s and 1990’s the demand for resources shifted to specific habitats and landscape patterns. Some of the western States began to set up regulations that had to with spatial relationships among individual stands and with proximity to streams and wildlife. These additional demands added spatial constraints to the already expanding list of parameters that had to be considered when developing a long-term sustainable yield analysis for a large tract of land. This wide array of constraints caused more work to go into developing alternatives to the linear programming models since the number of constraints was overwhelming the models. The binary search models, such as ECHO (Walker, 1971) and TREES (Tedder etal, 1980), provided the ability to consider an open-ended number of constraints and options. The binary search models could schedule larger databases than the linear programming models because the computer utilities could continually search the database one record at a time until the best schedule was found regardless of the size of the computer file. Linked to the development of ‘in-place’ inventory systems has been the development of geographic information systems (GIS). Because this technology evolved out of computer assisted drafting techniques, the concept of maintaining a list of attributes for the polygon arcs and lines was late in developing. As a result, the forest industry has access to some very sophisticated GIS software utilities. However, these utilities have not emphasized development of strong relational databases to carry the large number of attributes common to a forest inventory database.


Some companies and some consulting firms have spent months and years in human resources and budgets developed their own unique inventory database software to carry this array of forestry attributes. With the development of micro-computers have come very sophisticated relational database software utilities such as Microsoft’s Access. These database utilities surpass anything attempted in the forest industry and are being updated and supported on a regular basis. Custom-built forest inventory systems now have all become obsolete in less time than it took to develop them. Examples are easy to identify in both large forest industry organizations and private consulting firms promoting their unique inventory systems only a decade ago. Tied to the software and hardware evolution in micro-computers is the drive to standardize among all vendors of software utilities. This drive provides the forest industry, at no direct cost, with the array of tools that have been needed since the desire in the early 1960’s to develop long-range sustained yield plans in the forest industry. The conflicting demands for management among multiple resources on each acre of forest land have elevated stand silvicultural prescriptions to a spatially complex problem. Since most of the developmental research in harvest scheduling in the 1980s and 1990s focused on linear programming techniques, these approaches to forest planning have persisted beyond their capacity to be effective. This is due to the basic underlying strategy of linear programming techniques. The forest is divided into a series of strata – usually site, age, species, stocking, and silvicultural regimes. The linear programming algorithm then allocates acres among the strata over the periods in the planning horizon (perhaps one year periods over 100 years). The output from the harvest scheduling analysis provides the total acres which may be harvested, thinning or otherwise silviculturally treated within each stratum in each period. If the number of acres within a given stratum and period are reasonably large (perhaps 1,000 acres or more), then the forester can locate an operational-sized stand polygon in the forest which matches that stratum and year. The harvest schedule is functionally operational. However, since the early 1990s the complexity and combination of spatial harvesting constraints has become extremely burdensome. Spotted owl regulations identify at least three circular areas extending from each nest site with unique thresholds of forest structure required for each area. Riparian buffers have expanded from single, no harvest buffers to multi-layered, variable-retention harvesting constraints. Other slope, soil and cultural constraints place limits on the kind of final harvest allowed (clearcut, seed-tree, shelterwood, or individual tree selection-only). Even-aged harvest methods are subject to time delays due to neighbor green-up constraints. These spatial constraints have been integrated into the evolving linear programming harvest scheduling models with limited success. Examples are well known within some large forestry private ownerships that have attempted harvest planning using the linear programming approach. However, these results are not well known publically since this type of forestry research is no longer supported from traditional sources (USDA). The problem is that the spatial overlays are used to “cookie cut” the forest inventory stand polygons into discrete pieces for each specified combination of constraints. This is done


within the overlay of strata required to conduct the harvest scheduling analysis to produce acres resulting in each period for each stratum. Specific examples include the 90,000 acre Seattle Cedar River watershed and the 200,000-acre Scotia-Pacific bankruptcy litigation. In each case, the overlay of all strata and constraint criteria created discrete polygons within the linear programming analysis which were less than 2.5 acres in size. The linear programming algorithms had to use post-processing methodologies to find pieces sufficiently close in geographic proximity to create a harvest block of operational size. The overall result is far from an optimal solution. In fact, over time spatial constraints become operationally infeasible due to post-processing tradeoffs. The binary search harvest schedulers of the 1970s lost momentum due to a concern that they produced sub-optimal results compared to the more mathematically rigorous linear programming methods of that period. In the current environment of complex spatial programming methods, the binary search method has significant benefits. This again, due to declines in publicly-supported forestry research, has not been well recognized. The essential difference for binary search from linear programming methods is that the stand polygon in the forest inventory maintains its spatial integrity. The binary search methodology tests each polygon in each period for each separate silvicultural strategy as a whole stand, not pieces. Therefore, once the harvest scheduling analysis is complete, each inventory stand polygon has been allocated to a unique silvicultural and harvest schedule timetable. The forester has an easily recognizable and functional forest plan. No post processing is necessary. This is extremely easy to verify by displaying a theme of scheduled pieces by period and silvicultural regime from a linear programming analysis compared to a theme of stands by period and regime from a binary search analysis. The 90,000-acre example produced a theme map of 3,600 stand polygons with assigned treatment regimes from the binary search analysis and 42,000 polygons with assigned treatment regimes from the linear programming analysis (prior to post-processing to create operational blocks). Knowledge of efficient, reliable and defensible harvest scheduling methods is integral to commitment to long-term forest ownership and management. This is especially the requirement in a social environment of oversight by special interest groups, regulatory agencies and limited expectations of a robust forest economy. The mensurational integration of these inventory, growth projection and harvest scheduling methods continues to be the foundation necessary for a defensible forest management strategy. In the latter part of the 1980s, various natural resource interest groups began to promote concerns about clear-cutting practices and their impact on wildlife and the environment. This promoted new interest in alternative methods of final harvest such as seed-tree, shelterwood and selection harvesting methods. The whole stand and tree-list growth models developed from even-aged, single species databases provided limited capacity for projecting all-aged, mixed-species stands, especially when it came to incorporating natural regeneration through the projection horizon. These older models also relied on King’s (1966) site index, height/age curves for stand projection from age zero. By 1990 many plantations were exhibiting significantly faster growth rates than anticipated in the original 1970s growth models.


The tree-list, distance-dependent growth models by Arney (1972) and Mitchell (1975) had the capacity to handle these more complex stand structures, but they each had their own limitations. The TASS model (Mitchell, 1975) was designed to only start from bare ground for each projection. It could not input an existing inventory stand as a starting condition. The tree-list model by Arney (1972) had very little data behind the initial development of parameters and it was not compatible with the Microsoft Windows environment common to the forest inventory and GIS technologies in application throughout the West by 1995. Therefore, Arney (1996) conducted a one-year project in Western Oregon to calibrate this tree-list, distance-dependent growth model. It was based on the original 1972 growth modeling architecture but modified to accept a variable number of regions and species. The software was re-written to provide a completely integrated Window-based set of mensurational tools compatible with current forest inventory computer systems. Participants in this Western Oregon Calibration included: Cavenham Forest Resources (formerly Crown Zellerbach) Lone Rock Timber Company Northwest Tree Improvement Cooperative Oregon State Forest Research Laboratory Roseburg Forest Products USDI – Bureau of Land Management USDA – Forest Service, PNW Experiment Station Weyerhaeuser Company The growth model developed from the Western Oregon analysis was the Forest Projection System (FPS) and the Regional Library was identified as Region 11. Then Arney (1997) conducted a Western Washington growth model analysis using the same FPS architecture in a one-year project with the following participants: International Paper Company Murray Pacific Corporation Northwest Tree Improvement Cooperative Oregon State Forestry Research Laboratory Pope Resources Washington Department of Natural Resources USDI – Bureau of Land Management USDA – Forest Service, PNW Experiment Station Weyerhaeuser Company The growth model developed from the Western Washington analysis was identified as FPS Region 12.


Next Arney (1999) conducted an Inland Northwest growth and yield cooperative project to calibrate FPS for inland species. Participants for that analysis included: Boise Cascade Corporation Colville Tribal Forestry Coeur d’Alene Tribal Forestry Flathead Tribal Forestry Idaho Department of Lands Montana Department of Natural Resources and Conservation Nez Perce Tribal Forestry Plum Creek Timber Company Potlatch Corporation Spokane Tribal Forestry University of Montana Mission-Oriented Research Program US Forest Service Experiment Stations Warm Springs Tribal Forestry Washington Department of Natural Resources Yakima Tribal Forestry The growth model Regional Libraries developed from these analyses included Region 13 – Eastern Washington; 14 – North Idaho and Western Montana; and, 15 – Eastern Oregon. In 1993, Dave Hann (2007) completed a five-year analysis of the tree-list, distance independent growth model, ORGANON, for Douglas and Jefferson Counties in Southwest Oregon. Total cost of the analysis contributed by Boise Cascade and USDI – Bureau of Land Management was five million dollars. The growth model ran in a Microsoft DOS Window requiring text file inputs and outputs. This model never gained a significant level of acceptance by the forest industry due to its text file requirements and limited number of species included. To be functionally incorporated into an operational forestry organization required that organization to employ a computer programmer to build all interfaces between the inventory database, growth model and harvest scheduling utilities. A few companies were large enough to justify this investment, but most were not. Later, a dynamic-link library (DLL) routine of ORGANON was released, but this too required a computer analyst to be maintained within each company that proposed to use this version of the model. As a result, the model has been used in case-study analyses from time to time, but it has never become a work horse inventory update and harvest input functioning growth model. These results from the release of new mensurational technologies that do not get embraced and accepted by the forest industry are not so much the fault of the forest analyst imbedded in the project. These results are mostly due to a lack of understanding by the host organization (University or Experiment Station) about the evolving industry needs and how these new technologies integrate into the other current technologies being applied within the forest industry. The analytical investments in DFSIM and in ORGANON were significant and historically important. However, they were both delivered slightly behind the evolution of technology in the forest industry. The result


was predictable had anyone evaluated the impacts of ongoing developments in other mensurational endeavors (inventory and planning in these cases). This situation is not unique within forestry research on growth models. The desire by many companies to get involved in forestry research and development was discussed earlier as the catalyst which caused a wide array of research cooperative programs to emerge. A mentioned earlier, these cooperative research programs were primarily hosted by universities with faculty members as the project directors. Significant amounts of funding have gone through these cooperative research programs over the past three decades. These programs have installed extensive numbers of field trials in genetics, fertilization, thinning, vegetation control, nursery practices and planting stock. However, the benefits to the faculty member for investing in these programs were never adjusted to recognize these commitments. As a result, the university cooperatives have installed, measured and collected vast amounts of research information. However, once the faculty member develops preliminary results there is an immediate push to publish these results in a “refereed” journal. This is essential to the faculty member for merit salary advancement. However, the forest industry participants are left with minimal conclusions, tools and procedures to implement these results into their internal forest planning analyses. Further, the faculty member receives no merit for providing ongoing support of previous published results. Consequently, most cooperatives have gathered great amounts of research information and have provided little technology transfer to the industry cooperators or ongoing technology support. With more difficult economic times, these research cooperatives will cease to exist due to a lack of insight at the outset about what constituted the full depth of a robust research and development program. The research must be current, relevant and supported for the project to endure. Meanwhile by 2000, Arney had calibrated a standard set of FPS growth models for twenty-six commercial tree species in seven States and two Canadian Provinces. Each analysis required approximately one and one-half years to complete with an average cost of approximately sixty thousand dollars each. Declining funding of forestry research through 1985 – 2005 has resulted in the following summary of ongoing growth model support in the West:

Growth Model Developer Status

Prognosis Al Stage / Bill Wycoff Retired FVS (Prognosis) Ralph Johnson / Gary Dixon Retired

DFSIM Bob Curtis / Gary Clendenen Retired TASS Ken Mitchell Retired Cactos Lee Wensel Retired Cryptos Lee Wensel Retired

ORGANON Dave Hann ? SPS Jim Arney Not supported FPS Jim Arney Active

PPSIM Don DeMars / Jim Barrett Retired


These funding shortfalls were affecting the forestry schools as well. Undergraduate and graduate student interests shifted to environmental sciences and away from quantitative sciences such as mensuration and statistics. Faculty retirements in mensuration and timber management have been (and are being) replaced with emphasis in wildlife, environment and social sciences. In 1995 Richard Zabel, Western Forestry & Conservation Association (WFCA) Director, asked Jim Arney to initiate a series of professional workshops on forest inventory, growth and planning. Together with Dr. Kim Iles6 and Dr. Larry Zuller7, they conducted a series of workshops over the next five years that quickly became the most popular workshop ever provided by WFCA. Even though public support was declining for forest mensuration methods and tools, the forest industry organizations were in desperate need of these technologies. A pronounced and dramatic shift in forestry was taking place. It was and is still shifting in 2009. The changes continue to evolve and the final status is not known. This is having a permanent affect on forestry research, development and education throughout the West. Sadly, the research activities prominent in most of the US Forest Experiment Stations, universities and cooperatives in past years have only emphasized individual components of forest management. Typical of this view are research activities regarding sampling designs, nursery practice, nutrient gains, genetic selection, herbicides, growth models and more recently environmental concerns. None of this is integrated into an overall framework for a forest land management organization to integrate into their forest planning structure. However, pieces of these research programs do get integrated into various public regulatory structures which act to constrain the options available to the forest landowner. This situation only increases the risk of more aggressive silvicultural scenarios when benefit and risk are difficult to quantify. The outcome has been a trend away from intensive forest management to more custodial approaches or outright disposal of the ownership. Where are we now?

In the 1960s it was typically required in the university senior year of forest management to work in teams in a classroom and field setting to develop a forest inventory, yield projections and alternative harvest schedules. They integrated these components into a final report which produced a recommended forest management plan for a school forest or large tract of land. The graduating seniors were expected to understand and implement these types of planning activities upon successful employment in a forestry organization. That expectation by the employer is not different in 2009, but the methods are no longer taught nor exercised in the university setting prior to graduation. As a result, the graduating foresters are not equipped to handle the range of tasks essential to developing an active forest management plan for the organizations who have hired them. This conclusion has been confirmed repeatedly in excess of 28 post-graduate workshops in the past fifteen years where the land management organization is paying the workshop fees.

6 Dr. Kim Iles & Associates, Professional Forestry Consultant. Formerly MacMillan Bloedel. 7 Dr. Larry Zuller, Professional Forestry Consultant, Formerly Georgia Pacific.


The forestry education is now happening after graduation with a B.S. degree in forestry, not before. In 2002 the National Research Council established a committee to look into the status of forestry research in the United States. The report, “National Capacity in Forestry Research”, has some very specific observations and conclusions (Cubbage et al, 2002). These include:

“Our national capacity in forestry research appears to have waned even as the

demands placed on our forests and the need for enhanced technical knowledge have

increased.”

“The reduction in capacity in the USDA Forest Service is cause for concern.”

“In the committee’s opinion forestry research capacity is at a crossroads, if not a

precipice.”

“In brief, this report suggests that our current forestry research capacity is neither

adequate now, nor poised for success in the coming years. This report identifies

significant declines in real research capacity, fragmented cooperation, and poor

communication among principal providers and users of forestry research, inadequate

support of both foundation and emerging disciplines, and little strategic planning to

address future forestry research needs.”

“Declines in fundamental disciplines have been observed in faculty and support staff

of universities and natural resource agencies.” “University programs should assume

a renewed commitment to the fundamental areas of scholarship and research in forest

sciences that have diminished in recent years.”

“Our review and our recommendations can be used to shape future forestry-research

efforts, enhance research capacity, and encourage public and private interests to help

to achieve a strong research foundation for sustainable forest management.”

Significant portions of the report referred to establishing “Centers of excellence in forestry”. The concept was to bring research, development, education and implementation into an integrated program which would provide a permanent foundation while maintaining a forward-looking structure of effective and financial performance. One significant recommendation that continues to be overlooked:

“Recommendation 5-2 Clear federal research facility mandates – such as long-

term ecological research sites, experimental forests and natural resource areas, and

watershed monitoring facilities – should receive priority for retention and

enhancement, and a system of periodic review of all facilities should be implemented

and maintained.”


What is missing – integration of technologies and how to use them. It is time to look past the individual components and to look at forest management as a whole. It does not matter what the intended forest management goal may be; the components are the same and the integration of forest dynamics, silvicultural options and administrative constraints must all be considered as an integrated composite. There is a core educational foundation that must be provided regardless of the mission or goal of the organization which employs these graduates. That core no longer exists in any forestry school in the West.

“Recommendation 4-2 Universities should develop joint programming in

geographic regions to ensure a ‘critical mass’ of faculty and mentoring expertise in

fields where expertise might be dispersed among the universities.”

In 1983, Arney wrote a two-page personal letter8 to every forestry dean in the West with a concern “about the strength of our biometrics research programs here in the Northwest”. The emphasis was on a fully integrated program in inventory, growth and planning technologies from research to education. Various responses resulted including the action by Dean Ben Stout at the University of Montana in hosting the newly formed Inland Northwest Growth & Yield Cooperative (INGY). It also facilitated the thrust into the Stand Management Cooperative (SMC) at the University of Washington. However, not one dean of a forestry school responded with an interest in taking on this leadership opportunity in forest mensuration. By 2002 this situation was apparent to the National Research Council committee resulting in Recommendation 4-2. It has now been seven years and no forestry school has taken on this challenge. An integrated forest management system is essential to each forest land manager. There is no assumption here that a fully integrated system provided from a research and development organization will meet all needs. However, it can set a standard or threshold as a reference for more customized or sophisticated approaches. This reference is essential for public acceptance of forest management as a profession grounded in fact and integrity. Too often the forest industry is presented as extracting the remnants of a “fixed natural resource” rather than managing a “renewable natural resource”. Since we provide no integrated view of forest management anywhere for public access, we are subject to all criticism, founded or un-founded, without defense. However, we could provide a standard. That standard should be a demonstration working forest with a sustainable forest management plan. Sustainability is undefined in much of the context which it is used in the current public dialogue about forest management. To determine if a crop is sustainable, it requires more than one harvest or rotation of that crop. The series of harvests make up the evidence of sustainability or the degree of sustainability. The degree of sustainability could imply a gradual decline, incline or variability over the time horizon of interest. For forest management the time horizon must be at least a full rotation of the crop or life span of the specific forest under consideration. Two rotations would provide good evidence of the degree of sustainability of the selected forest management plan. However, since a single

8 Personal correspondence. Dean John H. Ehrenreich, September 26, 1983. College of Forestry, Wildlife & Range Sciences, University of Idaho, Moscow, Idaho.


rotation encompasses decades of time, reasonable confidence in sustainability can be obtained in one and one-half rotations by close observation of the developing inventory relative to the scheduled (or anticipated) development. In a mensurational sense, this definition of sustainability provides wide latitudes of alternative management scenarios. For example, a four thousand acre tract is sustainable if eighty acres are harvested each year and replanted to be harvested again in fifty years. Every year has the same harvest and regeneration plan, forever. However, the same tract could be harvested completely (all acres) in one year and replanted. The plan would wait fifty years to then harvest the complete tract again and replant. Every fifty year cycle is the same, forever. This management plan is also sustainable, but the variability within the planning period is extreme. This second plan is likely to be not socially, politically or environmentally acceptable. Where then is the compromise for “sustainable” forest management? No existing forest ownership is completely balanced in all age classes and stages of development at this time. Therefore, how much variability is acceptable from year to year and decade to decade to achieve sustainability? Only an integrated forest management plan considering all soil, site, silviculture, wildlife and environmental factors can provide that answer. Where is that integrated planning system that everyone accepts as providing a defensible answer? It is not available from our federal experiment stations or universities. For forest management to be publically accepted, it must be demonstrated to be sustainable. The tools and techniques currently exist. There just has not been sufficient focus or commitment to integrate them into a reference point – a demonstration working forest. Where does all of this lead for forestry research and education? Here are the fundamentals that have been brought into focus:

1) Research and Development must be brought into an integrated forest management decision-making process to be useful and functional in an industry setting;

2) Expertise and facilities are scarce and too functionally dispersed to a degree that they have become ineffective for an ongoing dynamic research program;

3) Experimental forests and field research trials are ceasing to be accessible for ongoing research investigation and demonstration; and,

4) Education has lost much of its foundation in the basics of scientific forest management principles and practices.

Why has it been in our experience in the West that specific individuals have moved us forward in research, development and education primarily due to their own initiative rather than the institution with which they were associated? Examples are Dr. Kim Iles (2003 self-sponsored textbook on forest inventory), Dr. Mike Newton (retired professor with ongoing vegetation management research), Dr. John Bell (retired professor with ongoing continuing-education short-courses) and Dr. Jim Arney (ongoing growth model development and technical support). Perhaps our profession has not found the appropriate “center of excellence” organizational structure which could draw individuals of this quality and commitment to its core. Based on the recommendations of the National Research Council committee report on forestry research, now is the time to establish that core.


First, the client for this integrated forestry research, development, education and support structure must be identified in order to provide current prospective relative to past history. The operating forest land management organization includes those clients which actively manage private, industrial, native reservation, county, state and federal forest ownerships. In 2009 the typical organization is 50,000 to 500,000 acres in size employing one professional inventory/planning forester with 5 to 15 years experience and a B.S. degree in forest management. It is this professional forester who must provide the organization with all inventory updating, reporting, silvicultural regimes, growth projections, spatially-specific environmental restrictions, harvest levels and cash flow capacities to the senior management decision-making team. There is no room for error and no backup in staff. That single professional forester is easy to identify in each forest management organization. The forest land management organizational structure must also be considered when identifying the client for forestry research and development. The larger ownerships in acreage have been transitioning to Real Estate Investment Trusts (REITs) and similar corporate structures. As such the corporate forester is providing forest management options (long-term silvicultural plans) to financial investment professionals who have great difficulty looking beyond twenty years for any financial commitment. Therefore, investment in plantation management, nursery practices, vegetation control, genetic selection and longer rotation horizons get little consideration. At the opposite end of the forest management spectrum are the conservation organizations, federal, state and native reservations which are evolving toward simple custodial management regimes creating little wood or cash flow outputs. Attempts by a number of conservation organizations to convert even-aged management regimes of intolerant species (Douglas-fir and Ponderosa Pine) to all-aged regimes are resulting in substantially reduced wood flow capacities. This result will continue until those hosting organizations cease to financially support this management approach or transition the forest ownership to the public sector to be funded through pubic taxation. As a result of these changes in management structure from traditional corporate working tree farms there will be:

1) a greater demand for imported forest products due to the continuing desire for wood products;

2) a decline in forest health with an increase in fire severity; and 3) a departure from intensive forest management practices and benefits.

The most troubling aspect of these developments is the fact that no integrated forest management display of impacts from these different management styles is publically provided from any professional forestry research facility. Forest policy and decisions are being developed in a fog with no clear scientific foundation.


Where to from here? Given the declining status of our federal research programs and university staffing, the 2002 National Science Council recommendation to develop regional “centers of excellence” in foundation forestry sciences is compelling. Drs. Jim Arney and Kelsey Milner established the Forest Biometrics Research Institute (FBRI) in 2002 just as the National Science Council report was being published. They obtained IRS 501 (c) 3 non-profit research corporation status for the Institute effective August 14, 2003. Through cooperative database sharing agreements and past research by Arney, the Institute has gathered the single largest and most complete permanent plot research database in the West. Growth projections for natural stands, plantations, vegetation control, fertilization and thinning in over two dozen species throughout the West have been developed and verified from these databases. The FBRI maintains, enhances and supports a fully integrated inventory, growth projection and harvest scheduling software system for use by all forest management organizations. It provides a textbook, “Biometrics of Forest Inventory, Forest Growth and Forest Planning” (Arney, Milner and Kleinhenz, 2007) and an annual series of continuing educational workshops in forest management methods, practices and tools. Over fifty forest land management organizations support the research, development, education and service functions of FBRI. This organizational structure is unique in forestry but common in many other disciplines. A non-profit corporation exists to serve a mission. That mission for FBRI is enhancement and application of forest biometric methods and principles. It cannot deviate from that mission. Over the past forty years foresters have observed this mission to change within other structures including USDA Forest Service Experiment Stations, Universities, research cooperatives and consulting organizations. The rates of these changes have depended on the personalities in management positions in various years. Perhaps the FBRI non-profit mission is the structure which the National Science Council committee was attempting to discover? On this basis it is fair to draw current comparisons of the alternative “sources” of integrated forest management tools available to the forest industry. Availability used here includes: a) ongoing research; b) development; and, c) support.


Functionality USFS - FVS USFS – DFSIM OSU -

ORGANON

FBRI - FPS

Inventory management x Live database update x Cruise compilation x Live GIS updates x Cruise expansion x Re- Merchandiser x Harvest depletion x Stand projections x x x x Tree list input/output x x x Natural Regeneration x Vegetation Silviculture x Volume/Weight/Carbon x Soil/Site models x Multiple Regions x x Periodic Refinements x Discounted Cash Flow x Harvest scheduling x Spatial constraints x Alternative Regimes x Binary Stand Selection x Volume/Carbon/Value x Technical support x Supporting Staff x Ongoing development x Annual short courses x Field Research Trials x SQL Server databases x ODBC databases x Customizable database x Windows GUI x x USFS – FVS reference: Wykoff, Crookston and Stage, 1982. USFS – DFSIM reference: Curtis, Clendenen and DeMars, 1981. OSU – ORGANON reference: Hann, 2007. FBRI – FPS reference: Arney, Milner and Kleinhenz, 2007. These “functionality” titles are cryptic, but the message is compelling. It appears time to leave behind the one scientist / one model format for growth and yield research. Basic structures and functional designs have been developed and established in most forest land management organizations. These organizations rely on stand-based inventories linked to dynamic GIS database systems, growth models and spatially-sensitive harvest


scheduling systems. The principal investigators of all USFS growth models have retired and their programs terminated. University faculty incentive structures do not encourage ongoing technical support or development of industry-desired methods or tools. This one scientist/model template from past research in site capacity, taper and volume determination, growth model architecture and forest planning models has become out-of-date. All of these technologies are now required components of fully integrated forest management strategies, tools and educational structures. Further expansion of scientific exploration and knowledge building in these technologies will only be successful if approached through inter-disciplinary teams rather than the one scientist, one model format. Previously Jim King could build a site curve, Jim Girard could build a taper table, Al Stage could build a growth model and John Sessions could build a spatial allocation model. Each of these technologies was developed with little interaction from the others. However, now these technologies must become components in fully integrated forest management systems. Further research and development success will benefit from a team approach of soils (type, water, nutrient), computer (software, databases, GIS), silviculture (species, vigor, tolerance, regeneration, nutrients, life forms), climate (growing seasons, precipitation, seasonal – decadal – century), wildlife (animal, insect, microbial) and topographic (three dimensional units in time – tree, stand, forest, region) specialists. It is not in the best interest of the forestry profession to continue in previous formats of fragmented research projects which gain or decline based on one individual. It is time to review the foundation of forestry research structure from the past and how to best structure forestry research in future. Everything a forest manager uses is now part of larger, integrated systems. To further the strength of these systems requires integrated research programs. Technical progress in the 1970s and 1980s was driven from individual insight. Witness the technological insights derived from the rich series of Ph.D. dissertations about 1970, such as Monty Newnham (1964 – UBC); Jim Lee (1967 – UBC); Rolfe Leary (1968 – Purdue); Jim Lin (1969 – Duke); Ken Mitchell (1969 – Yale); Imre Bella (1970 – UBC); Paille (1970 – UBC); Jim Arney (1972 – OSU). Each of these contributed to a rapid transition from printed yield tables to computerized growth models in the West. The task in 2009 – 2010 is to find and support the R&D organizational structure which fosters continued research and development in core forest measurements (inventory, growth projection, silviculture, harvest planning). Our profession cannot rely on the chance that another series of individuals will find the skills, interest and insight to move us forward as we have benefitted from in past decades. The last decade (1998 – 2008) has provided little new useful technologies over those developed in the previous two decades (1978 – 1988 and 1988 – 1998). As well documented in the National Science Council report (Cubbage et al, 2002), forestry research is clearly in decline. It is also time to look beyond the one State / one (or more) forestry school format for undergraduate and graduate education in foundation forestry sciences. Although there remain questions about existing tenured faculty positions; those are university


administrative problems, not forestry education problems. Programs at all western universities should be compressed into a single geographic center to provide a robust critical mass of expertise essential to future graduate research and education in the forestry sciences. Leaders from the following universities should determine the role, if any, which their university may play in the future of forestry education. No existing university forestry program currently meets our needs.

State University

Washington University of Washington Washington State University

Idaho University of Idaho Montana University of Montana Oregon Oregon State University

California University of California – Berkeley Humboldt State University California Polytechnical Institute

Colorado Colorado State University Arizona Arizona State University

One Northwest geographic center could provide the critical mass if it includes:

1) A University undergraduate and graduate educational program and staff in the foundation sciences of forest management using current inventories from a working research experimental forest;

a. Sophomore program

i. Forest sampling (stands), Stand sampling (Plots), Sub-sampling (Trees, shrubs, snags)

ii. Inventory maintenance (MS-Access), PC-based GIS, Acreage adjustments for roads and buffers, depletion updates

iii. Annual forest sampling frequency and intensity iv. Site distribution and means to classify and validate v. Habitat classification and update methods

b. Junior program

i. Inventory growth projection methods 1. Applications, Constraints, Validation

ii. Silvicultural systems and yield differences 1. Clearcut regimes, preferred species & densities 2. Seed Tree regimes, regeneration systems 3. Shelterwood regimes, habitat implications 4. Selection regimes, single-tree versus group

iii. Forest health, vigor, regeneration, tolerance 1. Species selection, vigor, plantation culture

c. Senior program

i. Harvest scheduling methods linked to GIS 1. Hydro, Wildlife, Watershed & Neighbors

ii. Planning horizons for 100 years versus 5 or 50 years iii. Impact and silviculture of 2nd & 3rd rotations


iv. Standards of merchandising and valuation v. Regulation by Area, Volume, Value or NPV

vi. Harvest unit polygons versus Stand polygons d. Graduate program

i. Solid foundation in forest measurements and sample statistics ii. Review and research major biometric principals

iii. Develop foundation in GIS and computer skills iv. Exercise scientific method through independent research.

2) One Research Institute as a center of research and development maintaining and

enhancing: a. standard forest inventory methods, tools and documentation b. standard forest growth and decline models and documentation c. standard forest planning models, spatial reporting and methods d. standard libraries by region and species of growth capacities, genetics,

structure (form, bark, crown) and vigor (tolerance, resistance) e. permanent databases of all regional research trials both historical and

current programs including vegetation, soils and climate parameters; 3) One Research Experimental Forest containing a self-sustaining, active forest

management plan of harvest and renewal (approximately 4,000 acres) interspersed with research trials on species regeneration and silviculture (1,000 acres). This working forest will provide direct public demonstration of sustainable forest management (forest, wildlife, ecosystem, financial), maintenance of long-term research, and university student firsthand experience; and,

4) A Continuing Educational Program for operational forestry organizations which facilitates technology transfer from research to education to practice. A series of short courses should be established at each experimental forest including field and laboratory exercises incorporating all ongoing and new technologies from all forest management-related sources. These include species selection, nursery practices, silviculture, wildlife, edaphic, climatic, regulatory and society influences on forest practices. This suggests a full-time program in continuing education at each experimental forest including facilities and staff. If society expects to encourage successful industries; then these industries will require the best technologies and training to remain successful. It is the successful industries of our communities which provide long-term employment, stability and basis of public funding (taxation) for schools, roads and community services. Personal health and wellbeing is based on community health; and community health is based on the source of support which maintains that community. It is critical to protect and enhance those sources of community support. University education is a foundation, but continuing education provides maintenance of health and vigor within our profession.

The Forest Biometrics Research Institute has identified itself as a focal point for forest biometrics research, development, education and service. It is structured and functioning to fulfill Item (2) in the previous series of recommendations. FBRI is attempting to locate and incorporate existing regional field research trials and experimental forests


(Item 3). The FBRI has also been conducting annual continuing education professional workshops in inventory, growth projection and harvest planning (Item 4). The Western Forestry & Conservation Association (WFCA) has evolved to a status in 2009 where its sole purpose appears to be to provide ongoing short-courses for professional foresters. Apparently no research or educational organization (beyond FBRI and WFCA) has taken up this banner and that is a concern. This review and forecast is not about any individual person or organization. It is simply what has transpired in our recent past and the view of the future as shared by this author and thoroughly presented in the National Science Council report (Cubbage et al, 2002). Undergraduate education programs are incomplete and ill-designed to equip the graduating forester for the current requirements of the practicing forestry profession. Existing slates of coursework are redundant and incomplete. They have fallen below an acceptable level to provide fully-enabled forestry professionals as outlined in the previous sophomore to senior depth of understanding. It appears that practicing professional foresters must speak up publically to help change the current lack of focus and direction in forestry education. Forest “research, development and education” is indeed at a crossroads, it is time to make critical decisions for the future.


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Mitchell, Kenneth J. 1969. Simulation of the growth of even-aged stands of White Spruce. School of Forestry, Yale University. New Haven, Connecticut. Bulletin No. 75. 48 pages.

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