OSU Libraries | OSU Home

Leaving our legacy

April 30, 2015

 

The history and legacy of the western United States involve more than just cowboys and covered wagons. Tangible pieces of our past lay within mixed-conifer forests that dot the region. Trees not only form a vital part of the contemporary western U.S. ecological system, but that of the future, as well. Unfortunately, deforestation and poor management have threatened the benefits and beauty of these natural resources.

 

Author and OSU Professor Emeritus of Forestry John C. Tappeiner II joins us today to demonstrate the importance of analyzing and understanding silviculture, the study of forest growth and management. Tappeiner, along with three colleagues, is co-author of the recently released second edition of Silviculture and Ecology of Western U.S. Forests. Read on for a sneak peek at the text, introduced by Tappeiner’s commentary.

 

--------------------- 

 

This book focuses on the silviculture of western U.S. forests for two reasons. First, the authors’ careers were spent mainly in the forests of California, Oregon, Washington, and SilvicultureSecondEditionArizona, with some brief forays into southeastern Alaska, Montana, the Lake states, New England, and the Southeast. Most of our research and practical forest management work was done in Douglas-fir, ponderosa pine, lodgepole pine, true fir, and Sierra Nevada and southern Oregon mixed-conifer forests. Therefore, many of the examples we use are derived from either firsthand experience or the experience of colleagues in these forests. However, many of the species and forest types that we discuss occur throughout the western U.S., so the principles that we develop are valuable to the silviculture of western forests. With the help of excellent reviews and by consulting the literature, we have included considerable information from the interior west. Therefore our work is of value throughout the West. 

 

The authors believe that silviculture can help resolve many of today’s forest management controversies. Frequently we hear debates about forest management that reach an impasse. We think that these impasses are least partially the result of an incomplete understanding of silviculture and forest growth and development. We hope that the ideas and information in our book will reduce the “sharp edges” and controversies in the forest management debate and lead to more informed, fruitful discussions.

 

 

EXCERPT

Uncertainty and the Long-Term Nature of Silviculture

Taken from Chapter 1: Silviculture, p. 13-14

 

"Silvicultural systems are by their nature long-term. It is sobering to remember the length of time required for a forest stand to develop and mature. This process may span the careers of several forest managers and, in contemporary society, several changes in forest policy as well. A 50-yr-old stand is comparatively young by western forest standards. Thus foresters—and society at large—have only modest “control” over silvicultural systems and stand and forest development. It is wise to view silvicultural systems as “working hypotheses” of stand development, as Smith et al. (1997) suggest. Silvicultural systems will often have to be modified for several reasons. Natural events such as windthrow, insect and pathogen outbreaks, fire, and unexpected regeneration of trees or shrubs occur frequently and may alter stand density and species composition. Shifts in policy, markets for forest products, landowners’ need for income, and public attitudes often require reevaluation of, and changes to, systems. Furthermore, new information on silvicultural practices, plant biology, or forest ecology may provide new insights and reasons for modifying systems.

 

"Given the inherent uncertainty in the enterprise of tending forests, we believe that one important principle is that a silvicultural system should preserve future options. An example is the shift in silvicultural theory and practice in response to an outbreak of Swiss needle cast disease (Phaeocryptopus gaeumannii) on thousands of acres of Douglas-fir in northwestern Oregon. Stands with mixtures of western hemlock and other species may come through the episode better than pure stands of Douglas-fir; these other species probably do not retard the spread of the disease, but if they are present they can replace Douglas-fir killed or damaged by it. Silviculturists who worked to produce pure Douglas-fir stands for economic efficiency and high yield are consequently reevaluating that practice on sites where needle cast is common As a result, in disease-prone stands where western redcedar, red alder, and western hemlock can grow, managers may either plant these species along with Douglas-fir or favor them where they regenerate naturally. The outcome in terms of species composition, wildlife habitat, and forest yield is not yet known, but a mixture of species will minimize the risk of losing an entire stand. Even though some species in the mix are of less commercial value, this silvicultural strategy will maintain future options better than continuing to plant only commercially valuable trees susceptible to the disease.

 

"Given the present rate of change in public sentiment toward forestry, and resulting changes in regulations constraining silvicultural practices, one may start to question whether the concept of a silvicultural system is even viable (Shindler et al. 2002). The context of the discussion often changes too rapidly for systems to be fully implemented, tested, and understood. Environmental issues change rapidly, and new regulations proliferate must faster than the typical cycle of thinning or harvest of an even-aged stand. From an even broader perspective, potential climate change and human population growth almost guarantee that the objectives guiding the design of current silvicultural systems will be modified.

 

"Numerous creative solutions have been proposed for meeting concurrent commodity and amenity objectives, but many of these are silvicultural treatments designed to produce certain stand structures over a relatively short term. These innovative treatments are often not well integrated into comprehensive silvicultural systems. A given treatment may be designed to produce a certain type of stand or vegetation structure, but the longevity of that structure and the future dynamics of the stand may be only superficially considered and understood. For example, it has been proposed that groups of trees or single trees be left after harvesting of even-aged stands. These trees are intended to provide structural diversity in the next stand and help certain organisms survive from one stand to the next. However, it is not clear how the trees around these groups and individuals should be managed. For example, should they be thinned or underburned? The practice raises other questions. Is it necessary to carry over young trees in stands being managed on short rotations? If so, what species and how many trees should be left? Finally, it is an open question whether those trees will actually function as intended for conserving biodiversity."

 

Tappeiner et al., 2015

 

REVIEW

“This is a great basic overview of silviculture theory… It is nice to know there are efforts to infuse the next generation of silviculturists with a basic knowledge of ecology.”

 

Goodreads user Gabrielle on May 24, 2008

 

---------------------

 

John C. Tapeiner II is Professor Emeritus in the Department of Forest Engineering, Resources, and Management at Oregon State University.

 

Douglas A. Maguire is the N.B. and Jacqueline Giustina Professor of Forest Management in the Department of Forest Engineering, Resources, and Management at Oregon State University.

 

Timothy B. Harrington is a Research Forester for the Pacific Northwest Research Station, USDA Forest Service in Olympia, Washington.

 

John D. Bailey is an Associate Professor in the Department of Forest Engineering, Resources, and Management at Oregon State University.

Post new comment

The content of this field is kept private and will not be shown publicly.
Member of AAUP