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The Role of Silviculture in New Forestry

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The Role of Silviculture in New Forestry by 1 Dean S. DeBell and Robet 0. Curtis ABSTRACT Silviculturists have had less influence on the early development of "New Forestry" than other resource specialists. As management objectives become more clearly defined and desired stand conditions are identified, silviculture will play a major role in developing practices to attain them. Silviculturists can provide several contributions to on-going discussions: knowledge regarding the heritage of conventional practices, tecriques for developing new practices, and other information pertinent to esolution of many issues and problems. The latter may include information on stand dynamics, silvical traits and silvicultural systems, opportunities afforded with planting, and rotation age and mean annual increment. ,· Silviculturists and other resource specialists must work together and develop an array of sound practices and strategies, which in combination, can provide the commodities and amenities desired in our forests. About , This ilef This File: . w. as crea ted by se . M ssca ann . th l ns Identi f mg e nted ied by the f Pn pu-blicati . ho wev so twar on , er, some e h ave be . ' mistakes en corre \ may rem . cted·.! am. '· 1 ... The authors are research foresters on the silviculture team, Pacific Northwest Research Station, USDA Forest Service, Olympia, Washington. 34. INTRODUCTION. Our assigned task is to discuss the role of silviculture in the development of New Forestry--or New Perspectives in Forestry--in the Pacific Northwest. Actually, there has been relatively little influence ·CO .. date of either silvicultural science or silviculturists in these movements. And understandably so. Silviculturists traditionally have been assigned to timber staffs, and they are viewed by many (and perhaps some silviculturists view themselves) as advocates of timber programs. Because a major thrust of New Perspectives is to move away from management philosophies dominated by timber production toward greater·consideration of other values, it is fitting that other resource specialists--ecologists, hydrologists, and wildlife biologists--have been the major contributors in developmental stages of these movements (Franklin et al. 1984; Franklin 1989). But as specific objectives become more clearly defined and desired stand conditions are identified, silviculturists and silvicultural science can be expected to play a major role in developing technology needed to attain them. And silvicultural activities will be the prary mechanism by which forest habitats are manipulated. But even during this present, rather fuzzy stage in the evolution of forest management and land-use decisions, silviculturists can play a useful role--at least in a general sense. There are contributions that ' silviculturists can make and should be making in the current quest for an improved and sustainable:forestry--one that is more socially acceptable, more economically viable, and more ecologically sound than what we have today (cf. DeBell 1990). Silviculturists can contribute information and 35 perspectives which are to some degree unique and are lacking in much of the present discussion. These include: (1) the history or heritage associated with current forest management practices, (2) techniques and approaches for development of new management practices, and (3) information pertinent to the resolution of many current issues or problems. HERITAGE OF CURRENT FOREST MANAGEMENT PRACTICES Much if not most of the institutional memory with regard to the heritage of forest management in the West resides in the silvicultural community. Other resource specialists-- and even many young silviculturists--commonly lack such background understanding. This forest management heritage includes a knowledge of major obstacles and problems overcome (the hews and whys of both problems and solutions) and of the many and very real accomplishments of the past 75 years. It also includes a cautious attitude that comes from past embarrassments associated with widespread adoption of. untested practices, and from major changes over time in Hat is deemed_t? be good stewardship as well as marked changes in the . inferences drawn from well-designed, long-term experiments . , , . · The greatest obstacle to management of western forests in the early decades of his century was the threat of catastrophic fire. Suppression techniques and fire control organizations were prerequis ite to any form of rnanagement . Approaches also had to be developed for seedling production and planting. Early on, decisions were made to replant and suppress fir,e on burned-over and cutover lands on National Forests. The growth capacity of young Douglas-fir was not well-defined until McArdle published 9ulletin 201 on growth and yield of unmanaged stands in 1930. This publication led to similar decisions by private owners to replant, protect, and manage their timber lands after harvest. Such decisions to stay and invest--rather than cut and run as had been done elsewhere in the country--were milestones in forest conservation. Unfortunately, the current controversy over preservation of additional amounts of residual old-growth on federal lands--and the rhetoric associated with it--has all but obscured such significat accomplishments and investments by the forest industry, states, and other landowners. As an aside--any solutions to current forest management issues that do not provide a favorable environment for investments in non-federal timberlands are likely to c=eate more problems--ecological, social, and economic--than they resolve. For example, we have already seen accelerated. premature cutting of young timber on private holdings in some parts of the Northwest, presumably caused by the uncertainty of future harvest restrictions and very high stumpage prices· created in part by severely limited public timber sales. Another aspect of our forest management heritage is humility and skepticism·developed as a consequence of past mistakes. Some of the biggest blunders were associated with widespread adoption of untested and 37 sometimes highly touted practices. One of the most embarrassing was the selective cutting episode of the 1930's and 1940's (Smith 1970}. It was proposed as a remedy to economic problems of the 1930's, and it was launched with a persuasive publication touting its merits and prefaced with a glowing endorsement by the Chief of the Forest Se;ice (Kirkland and Brandstrom 1936}. Although selective cutting became Standard Policy in Region 6, it was found wanting on a number of accounts--ecological and economic (Isaac 1955}. Finally, it was buried with a minimum of ceremony--so much so that many young foresters are not even aware of it. In the 1960's, another blunder was committed: the attempted transfer of management technoloJ that had been very successful in low- and mid-elevation forest to upper-slope forests--namely clearcut, burn, and plant Douglas-fir. Many of the harvested areas in the high elevation tre fir-hemlock types are now occupied by well-stocked young stands, thanks to natural seedig from adjacent stands. The planted Douglas-fir in most areas, however, are few in number and undistinguished in growth rate. Of lesser importance, but equally pertinent was the containerized regeneration fad of the 1970's . Theoretically, plug seedlings had several advantages over bareroot stock, d advocates convinced many decision-makers that reforestation was best accomplished via such technology. Some forest landowners discontinued long-established arrangements for bareroot prodution, much to their later dismay. Time and research revealed the advantages and shortcomings of various stock types and also led to improved methods for producing both container and bare-root stock. Containerization ( may be desirable for some species and some sites, but it appears that bareroot stock will continue to occupy a dominant place in reforestation in the Pacific Northwest. 38 - Such past mistakes and embarrassments foster a bit of healthy skepticism when practices--tough theoretically useful and desiable--are highly touted and idely implemented prior to any preliminary testing. Some silviculturists have drawn parallels between certain aspects of New Forestry and these old embarrassments. Such remarks have not always been offered in the most diplomatic manner, nor have the rejoinders from advocates, but they do provide useful background to aid in evaluating current problems and proposed solutions. A closely-related matter is the perspective provided by long-term experiments. Silviculturists in the Pacific Northwest are fortunate to have a number of studies that provide 60-80 years of record. These experiments involve topics ranging from selection of species and seed sources to questions related to stocking and to the influence of associated vegetation such as red alder on forest and soil development. It is an odd study that does not include evidence of drastic changes in interpretation over the years--sometimes the take-home lesson has reversed. Early performances and/or appearances were not good indicators of conditions as stands approached maturity. The magnitude and importance of such changes argues for a system of well-designed and implemented studies to assess the merits and drawbacks of current and newly proposed practices. the knowledge of forestry heritage should help us to retain the gains already made in forest conservation and prevent problems already solved from reappearing. It should also help us avoid new problems as new approaches are devised to meet additional
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