Ecological Restoration of Southwestern Ponderosa Pine Forests

By Peter Friederici and Gary Paul Nabhan

Ecological Restoration of Southwestern Ponderosa Pine Forests brings together practitioners and thinkers from a variety of fields—including forestry, biology, philosophy, ecology, political science, archaeology, botany, and geography—to synthesize what is known about ecological restoration in ponderosa pine forests and to consider the factors involved in developing and implementing a successful restoration effort. The book examines:

• the overall context for restoration—ecological, social, economic, political, and philosophical
• how ecosystem processes such as fire, hydrology, and nutrient cycling are affected by restoration activities
• treatment effects on specific ecosystem components such as trees, understory plants, animals, and rare or invasive species
• the details of implementing restoration projects, including smoke management, the protection of cultural resources, and monitoring

Each section is introduced with a case study that demonstrates some of the promise and pitfalls of restoration projects.

Ecological Restoration of Southwestern Ponderosa Pine Forests is the second book in the series The Science and Practice of Ecological Restoration from the Society for Ecological Restoration International and Island Press.

• Language: English
• Publisher: Island Press
• Release date: Apr 10, 2013
• ISBN: 9781597262965

Gary Paul Nabhan

Gary Paul Nabhan is an Ecumenical Franciscan Brother, MacArthur "genius" award winner, and ethnobotanist of Arab-American descent. His food and farming books include Food from the Radical Center, Where Our Food Comes From, and the forthcoming Jesus for Farmers and Fishers.

Book preview

e9781597262965_cover.jpg

ABOUT ISLAND PRESS

Island Press is the only nonprofit organization in the United States whose principal purpose is the publication of books on environmental issues and natural resource management. We provide solutions-oriented information to professionals, public officials, business and community leaders, and concerned citizens who are shaping responses to environmental problems.

In 2003, Island Press celebrates its nineteenth anniversary as the leading provider of timely and practical books that take a multidisciplinary approach to critical environmental concerns. Our growing list of titles reflects our commitment to bringing the best of an expanding body of literature to the environmental community throughout North America and the world.

Support for Island Press is provided by The Nathan Cummings Foundation, Geraldine R. Dodge Foundation, Doris Duke Charitable Foundation, Educational Foundation of America, The Charles Engelhard Foundation, The Ford Foundation, The George Gund Foundation, The Vira I. Heinz Endowment, The William and Flora Hewlett Foundation, Henry Luce Foundation, The John D. and Catherine T. MacArthur Foundation, The Andrew W. Mellon Foundation, The Moriah Fund, The Curtis and Edith Munson Foundation, National Fish and Wildlife Foundation, The New-Land Foundation, Oak Foundation, The Overbrook Foundation, The David and Lucile Packard Foundation, The Pew Charitable Trusts, The Rockefeller Foundation, The Winslow Foundation, and other generous donors.

The opinions expressed in this book are those of the author(s) and do not necessarily reflect the views of these foundations.

ABOUT THE SOCIETY FOR ECOLOGICAL RESTORATION INTERNATIONAL

The Society for Ecological Restoration International is an international nonprofit organization composed of members who are actively engaged in ecologically sensitive repair and management of ecosystems through an unusually broad array of experience, knowledge sets, and cultural perspectives.

The mission of SER International is to promote ecological restoration as a means of sustaining the diversity of life on Earth and reestablishing an ecologically healthy relationship between nature and culture.

SER International, 1955 W. Grant Road, Suite 150, Tucson, AZ 85745. Tel. [phone], Fax [phone], E-mail [e-mail], www.ser.org.

ABOUT THE ECOLOGICAL RESTORATION INSTITUTE AT NORTHERN ARIZONA UNIVERSITY

The Ecological Restoration Institute at Northern Arizona University works to restore degraded forests in dry, fire-adapted ecosystems of western North America. The goal of the ERI is to provide the best applied restoration knowledge in both ecological and socioeconomic disciplines to the public, nongovernmental organizations, state and federal agencies, academic researchers, and students. The ERI works closely with land management agencies, communities, and members of the public in assisting with the design, implementation, and monitoring of science-based treatments that restore forests while simultaneously reducing the threat of unnatural wildfire.

Ecological Restoration Institute, P.O. Box 15017, Flagstaff, AZ 86011. Tel. [phone], Fax [phone], www.eri.nau.edu.

Society for Ecological Restoration International

The Science and Practice of Ecological Restoration

James Aronson, editor

Donald A. Falk, associate editor

Wildlife Restoration: Techniques for Habitat Analysis and

Animal Monitoring

Michael L. Morrison

Ecological Restoration of Southwestern Ponderosa Pine Forests

edited by Peter Friederici, Ecological Restoration Institute

at Northern Arizona University

e9781597262965_i0001.jpg

Copyright © 2003 Arizona Board of Regents

All rights reserved under International and Pan-American Copyright Conventions. No part of this book may be reproduced in any form or by any means without permission in writing from the publisher: Island Press, 1718 Connecticut Ave., NW, Suite 300, Washington, DC 20009

Island Press is a trademark of The Center for Resource Economics.

Library of Congress Cataloging-in-Publication Data

Ecological restoration of southwestern Ponderosa pine forests / Edited

by Peter Friederici and Ecological Restoration Institute at Northern

Arizona University ; foreword by Gary Paul Nabhan.

p. cm.

Includes bibliographical references and index.

9781597262965

(pbk. : alk. paper)

1. Ponderosa pine—Southwestern States. 2. Forest

ecology—Southwestern States. 3. Restoration ecology—Southwestern

States. I. Friederici, Peter, 1963–II. Northern Arizona University.

Ecological Restoration Institute.

SD397.P6115E36 2003

577.3′0979—dc21

2003000628

British Cataloguing-in-Publication Data available

No copyright claim is made in the work of Malchus B. Baker Jr., Gretchen Barkmann, Phil Kemp, Laura P. Moser, José F. Negrón, Barbara G. Phillips, Carolyn Hull Sieg, and G. Thomas Zimmerman, employees of the federal government.

The financial support of the United States Bureau of Land Management under BLM Grant No. PAA-01-7002 is acknowledged in making this work possible.

The views and conclusions contained in this document are those of the authors and should not be interpreted as representing the opinions or policies of the U.S. Government. Mention of trade names or commercial products does not constitute their endorsement by the U.S. Government.

Printed on recycled, acid-free paper e9781597262965_i0002.jpg

09 08 07 06 05 04 03

10 9 8 7 6 5 4 3 2 1

Table of Contents

ABOUT ISLAND PRESS

ABOUT THE SOCIETY FOR ECOLOGICAL RESTORATION INTERNATIONAL

ABOUT THE ECOLOGICAL RESTORATION INSTITUTE AT NORTHERN ARIZONA UNIVERSITY

Title Page

Copyright Page

FOREWORD

ACKNOWLEDGMENTS

INTRODUCTION

PART I - The Context for Restoration

Chapter 1 - The Flagstaff Model

Chapter 2 - The Evolutionary and Historical Context

Chapter 3 - First Peoples in the Pines: Historical Ecology of Humans and Ponderosas

Chapter 4 - Ecological and Market Economics

Chapter 5 - The Governance Environment: Linking Science, Citizens, and Politics

Chapter 6 - Ecological Restoration as Thinking Like a Forest

PART II - Restoring Ecosystem Functions and Processes

Chapter 7 - The Ponderosa Pine Forest Partnership: Ecology, Economics, and Community Involvement in Forest Restoration

Chapter 8 - Fuels and Fire Behavior

Chapter 9 - Soils and Nutrients

Chapter 10 - Hydrology

Chapter 11 - Assessing Landscape-Level Influences of Forest Restoration on Animal Populations

PART III - Restoring and Protecting Biological Diversity

Chapter 12 - Healing the Region of Pines: Forest Restoration in Arizona’s Uinkaret Mountains

Chapter 13 - Tree Health and Forest Structure

Chapter 14 - Understory Vegetation

Chapter 15 - Exotic Invasive Plants

Chapter 16 - Vertebrates

Chapter 17 - Arthropod Responses: A Functional Approach

Chapter 18 - Threatened, Endangered, and Sensitive Species

PART IV - Conducting Restoration: Practical Concerns

Chapter 19 - Community-Based Forest Restoration

Chapter 20 - Ecological Restoration in the Urban–Wildland Interface

Chapter 21 - Air Quality and Smoke Management

Chapter 22 - Restoration and Cultural Resources

Chapter 23 - Monitoring

Chapter 24 - Adaptive Management and Ecological Restoration

Conclusion - Key Concepts and Questions in Adaptive Ecosystem Restoration of Ponderosa Pine Forest Ecosystems

APPENDIX 1 - Species Mentioned in Text

APPENDIX 2 - Threatened, Endangered, and Sensitive Vertebrate Species in Arizona, New Mexico, Southern Utah, and Colorado

APPENDIX 3 - Arizona Threatened, Endangered and Sensitive Plants Potentially Affected by Ponderosa Pine Forest Restoration

APPENDIX 4 - Colorado Threatened, Endangered and Sensitive Plants Potentially Affected by Ponderosa Pine Forest Restoration

APPENDIX 5 - Nevada Threatened, Endangered and Sensitive Plants Potentially Affected by Ponderosa Pine Forest Restoration

APPENDIX 6 - New Mexico Threatened, Endangered, and Sensitive Plants Potentially Affected by Ponderosa Pine Forest Restoration

APPENDIX 7 - Utah threatened, Endangered, and Sensitive Plants Potentially Affected by Ponderosa Pine Forest Restoration

REFERENCES

ABOUT THE CONTRIBUTORS

Index

Island Press Board of Directors

FOREWORD

Gary Paul Nabhan

The southwestern ponderosa pine forests explored and studied by pioneering ecologists John Wesley Powell, C. Hart Merriam, and Aldo Leopold are not the same as what we see, walk through, and manage today. Although still eagerly visited for their grandeur and wildness from the rims of the Grand Canyon to the heights of Mesa Verde and the remote valleys of the Gila Wilderness, these habitats have changed, sometimes subtly and sometimes dramatically, under the influence of skewed human perception, action, and inaction.

Fortunately, a talented team of scholars and restoration practitioners—many of whom are contributors to this volume—are broadening our views of ponderosa-dominated landscapes. Central to their work is the elaboration of a functional, evolutionary theory of ecosystem health that can guide pine habitat restoration much as Darwinian biomedical theory is freshly guiding the practices of preventing and treating diseases among humans. Unless we understand the conditions our species evolved under and adapted to, our interventions to prevent or control human disease are likely to miss the mark. By the same token, we need to understand the evolutionary ecology of ponderosa pine communities if we are to effectively prevent or control massive wildfires, devastating plagues or tree diseases, and infestations by invasive species. The authors of this volume are among a new cadre of ecosystem physicians and forest shamans practicing preventative and restorative medicine on a scale of unprecedented magnitude.

Our deeper understanding of forest history is key to this endeavor. The authors of this volume are looking at that history through many different lenses, thereby seeing the ecological and social processes affecting pine habitats with a degree of precision that scientists a few decades ago could only have dreamed of. This precision comes from using a variety of micro- and macro-lenses, rather than a single view. Native American land-use history, Anglo and Hispanic settlement history, dendrochronology, soil phytolith analyses, and ethical perspectives all give us distinctive views into the forest—and though these views may appear contradictory at first glance, they do largely complement one another. The wonderful legacy of the Ecological Restoration Institute’s efforts to understand the ponderosa forest’s reference conditions through such diverse lenses lies in how much true integration and synthesis of these varied disciplines and data sets it has been able to achieve, backed by experimental confirmation of hypothesized trends. It has carefully moved from the descriptive to the prescriptive while keeping a feedback loop between the two phases.

Writing this during a year in which more than half a million acres of ponderosa forest has burned in the region due to a tragic legacy of misperception—and in some places, mismanagement—I must underscore how much this work ultimately matters. It is critical to saving human lives and protecting cultural resources, from historic buildings to prehistoric heritage sites of irreplaceable value, but it is also critical to maintaining viable wildlife populations; to the furtherance of ecosystem services such as flood control, pollination, and air pollution abatement; and to the rational harvesting of timber and nontimber forest products. If this vision of ponderosa forest restoration proceeds—with modification, as new research refines our understanding of natural processes—it will lead to more habitat heterogeneity and to healthier habitats for a wide array of forest plants and animals. I cannot imagine that the health and well-being of human forest residents won’t tangibly improve as well. That the public will see the obvious, tangible links between healthy forests and healthy communities—and not a political facade that merely uses these words—is indeed our ultimate goal.

ACKNOWLEDGMENTS

This book owes its existence to the Ecological Restoration Institute at Northern Arizona University, where federally funded projects to develop and test ponderosa pine forest restoration techniques have been under way since 1995. Like this book, the ERI’s work in research, application of research results, and outreach has been a collaboration among numerous people, especially the university’s faculty, staff, and students. NAU president John Haeger and former president Clara Lovett deserve particular recognition for their work in establishing and strengthening the ERI. Without their support this book and much of the research and scholarship that undergird it would not have been possible.

This volume had its genesis in a research workshop conducted at NAU in February 2001, which was ably facilitated by David Bernard, Carol Murray, and Lorne Greig. The faculty, staff, and students of the Ecological Restoration Institute provided indispensable assistance throughout the process of writing and editing, especially Wally Covington, Pete Fulé, Diane Vosick, Doc Smith, Charlie Denton, Nikki Cooley, Roberta Tohannie, Lisa Machina, Dave Huffman, Jonathan Bakker, Mark Daniels, Linsey Baker, Chuck Bullington, Mary Hines, Gina Vance, and Judith Springer. Carl Fox, Claudette Piper, and Winnie Ennenga provided important logistical help and advice, as did Alan Poskanzer of Arizona State University.

The peer reviewers who read and commented on chapters contributed a great deal to this book’s comprehensiveness and clarity. Along with those acknowledged in individual chapters, they included Brian Cottam, Brad Ack, Tammy Randall-Parker, Christina Flynn, Michele James, Kieran Suckling, Scott Anderson, Julio Betancourt, Patrick Pynes, Andrea Hunter, Phyllis Hogan, Taylor McKinnon, Hal Rothman, Debra Larson, Tom Brown, Roger Blair, William R. Jordan III, Steven Davis, R. Bruce Hull, Brett KenCairn, Alan Farnsworth, Craig Allen, Steve Overby, Abe Springer, Leonard DeBano, Tom Heinlein, Gregory Aplet, Greg Taylor, Ken Moore, Tim Duck, Melissa Savage, Jonathan Bakker, Peter Ffolliott, Becky Kerns, John Randall, Scott Gillihan, Shaula Hedwall, Michael Rabe, Amy Waltz, Diana Six, R. William Mannan, Tad Theimer, Deborah Ulinski Potter, Janice Peterson, John Hanson, Linda Farnsworth, David Wilcox, Brian Nyberg, Barry Gold, and three anonymous reviewers. Janice Busco, Laura DeWald, and Norris Dodd also commented on and improved chapter drafts.

Others who contributed through provocative questions, discussion, and advice included Gary Paul Nabhan, Michele James, Stephen Germaine, John Gerritsma, David Taylor, Sharon Galbreath, and Michael Soulé. Michelle Volk, Dan Boone, Joel Viers, and Scott Curran assisted with illustrations. Sullivan/Santamaria Design created the maps. Don Falk and James Aronson of the Society for Ecological Restoration International helped shape both the book’s content and form. The book’s production would not have been possible at all without the tireless help of Barbara Dean and the staff at Island Press. Finally, though much of the research presented in this book has been made possible through federal funding, especially through the help of the Bureau of Land Management, the views and conclusions contained in this document are those of the authors and should not be interpreted as representing the opinions or policies of the U.S. government. Mention of trade names or commercial products does not constitute their endorsement by the U.S. government.

INTRODUCTION

Peter Friederici

It is the largest ponderosa pine (Pinus ponderosa) forest in the world—a swath of trees that extends from west-central New Mexico into northern Arizona, cloaking plateaus, canyons, and ridges with dark green foliage that provides a welcome respite from the arid, lower lands that surround it. And on June 18, 2002, it caught fire.

Driven by drought and high winds, what became known as the Rodeo-Chediski Fire exploded to 125,000 acres (50,000 hectares) within two days. Flames leaped hundreds of feet into the air. The smoke plume was visible from space. By the time the smoke cleared, two weeks later, the Rodeo-Chediski fire had burned more than 460,000 acres (186,000 hectares) of ponderosa pine forest, piñon-juniper woodland, and mixed conifer forest. It was the largest fire recorded in Arizona state history. Over 400 buildings had been destroyed, more than 30,000 people had been evacuated from their homes.

The fire was erratic; some areas within its perimeter retained living trees. But others—perhaps half the entire acreage—were devastated, shorn of all living vegetation. When the summer rains arrived in July, they eroded away ash and soil and washed this sediment into creeks and rivers. The areas most severely burned would not again support large, old-growth pine trees for centuries. For people living in or near the burned area, or downstream, it was a bitter reminder that human beings could not fully manage the forest to their liking.

Long needles in clumps of three, a sweet smell of vanilla and pine resin on the wind, the soughing of wind in limber branches, orange-yellow bark that flakes off in puzzle-piece shapes: ponderosa pine trees are a hallmark of the American West. Ponderosa and closely related pines grow on millions of acres from the cordillera of central Mexico to southern British Columbia, from the Sierra Nevada and the Cascade Range to the Black Hills. Nowhere do ponderosa pines more typify a region than in the southwestern states, where they grow sometimes in monotypic stands, sometimes mixed with other trees, across wide plateaus, in sheltered canyons, on steep slopes, isolated in sandstone pockets. They tower over grasses, wildflowers, and shrubs, or persevere in gnarled and stunted form on lava flows or cinder fields. Much of the material here will be of relevance to readers elsewhere in the species’ broad range—or to readers seeking to restore other ecosystems—but this book focuses on the ponderosa pine forests of the Southwest.

Fire has always shaped these forests—but not fires like the Rodeo-Chediski Fire. Detailed scientific evidence in the form of tree-ring records, studies of relict sites, and reconstructions of past forest conditions shows that fires in southwestern ponderosa pine forests were very common in the centuries and millennia before European-American settlers arrived, but generally not intense. They could be large, especially during years of drought, but they burned primarily on the ground and left large trees standing. What, then, has gone wrong?

Large fires that leap from crown to crown and consume entire stands of trees certainly are a natural phenomenon in parts of the American West—in lodgepole pine forests, for example, and in many montane mixed conifer and spruce-fir forests, and perhaps in some piñon-juniper woodlands. In ponderosa pine forests, though, they are an artifact of the modern era and of human intervention. Prior to the 1960s a 50-acre (20-hectare) crown fire in a southwestern ponderosa pine forest was considered large; in the 1970s, fires of hundreds of acres grew more common; by the 1990s, some fires killed ponderosa pine stands across tens of thousands of acres. The Rodeo-Chediski Fire was a degree of magnitude larger still. It could only have become as large and as severe as it did when it did. It could only become so damaging because thousands of people had built houses in forested terrain that previously had been undeveloped. It could only become so intense because decades of human-caused changes in forest conditions had disrupted the natural recycling and population control functions of low-intensity fire by filling the forest with a heavy load of dry woody fuels.

The fire underlined the increasingly stark choice faced by those who live and work in southwestern ponderosa pine forests: we can experience numerous small fires, or few but very damaging large ones. The fire-management strategy chosen by most forest managers during most of the twentieth century—attempting to effectively eradicate fire from the forest—is untenable. There is simply too much fuel in the forests, too much dry weather, and too many ignition sources in the form of lightning or careless or malicious people, to get rid of fire. These forests will burn whether we want them to or not. In 2002 extensive restrictions on forest access, sophisticated firefighting technology, and armies of firefighters were not enough to control the Rodeo-Chediski Fire.

We must choose, then, what sort of fire we want to have, and what sort of ecological role we want it to play. It is clear that frequent low-level fires are preferable according to virtually every indicator: they are less dangerous, preserve and maintain wildlife habitat and aesthetic values better, produce less smoke in the aggregate, result in far less erosion, and maintain ecological functioning and forest structure in ways that are less harmful to the forest as a whole. Even where they have not burned in high-intensity fires, most contemporary forests that have not experienced low-intensity fires for many decades are severely stressed. Their old trees are dying due to insect attack or competition with large numbers of young pines; their understory plant communities are impoverished due to lack of light, nutrients, and water; their faunal communities are altered.

Restoration of these forests, then, revolves around reintroducing such fires and reestablishing natural ecosystem patterns and processes. If we allow them, these fires can once again play the role they historically played in these forests, thinning out underbrush and trees, cycling nutrients, and stimulating the growth of grasses, wildflowers, and shrubs. In most circumstances, the goal of restoration is not, and cannot be, to return forests to precisely the condition they were in prior to Euro-American settlement, since some of the ecological changes that have taken place—such as species extinctions, climate change, and the introduction of noxious or invasive species—are essentially irreversible. It is, rather, to nudge their ecological trajectory so that they can return to a condition that is self-sustaining and compatible with the conditions under which their constituent organisms evolved.

Restoration acknowledges that these forests are dynamic, ever-changing places. It does not seek to turn them into museum pieces, but it does have a value system: namely, restoration is the putting into practice of the belief that most contemporary southwestern ponderosa pine forests are not healthy because they have departed too far from natural conditions, and that this lack of health has serious negative consequences for ecological functioning, for biodiversity, and for human values. Restoration lies at the heart of both good forest management and a healthy human role in the region’s forests. Though it focuses on much more than prevention of severe wildfires, it aligns well with the interest southwestern residents and decision-makers have shown in reducing fire danger in and around forest communities—as well as in the backcountry.

Restoration of these forests has extraordinary potential. Unlike many other ecosystems in need of restoration, southwestern ponderosa pine forests still cover vast acreage. Most have not undergone a type conversion to some other form of vegetation: they still are ponderosa pine forests, however altered. Most of their acreage is in public hands and is prized for recreation, aesthetics, wildlife habitat, and other values. Restoration of these forests matters deeply, and not just to ecologists.

The management of these public lands is also shaped by public desires and funded largely by public monies—and profoundly affected by a long history of contention between competing desires for resources. For these reasons, restoration can also be extraordinarily controversial. Reintroducing fire is difficult. At some level, many people still cling to Smokey Bear’s blanket condemnation of all fire. Residents regularly complain about smoke when management agencies conduct prescribed burns. The forests are so full of fuel that, during dry periods, almost any fire can become a conflagration. Research has also shown that simply reintroducing fire can have effects exactly opposite those desired by restorationists, as it can kill large, old pines while leaving young ones unscathed. As a result, it is often necessary to thin forests of woody fuels by cutting younger trees that have become overly dense before fire can be safely returned—that is, to mechanically alter stand structure so that fire can play its natural role in maintaining ecosystem patterns and processes.

Mechanical treatments can be controversial. Cutting trees leaves scars that many people do not like to see; alters wildlife habitat; can cause soil compaction and erosion; and can provide an entrée for invasive species. It is labor-intensive and often expensive, and has the potential to confound ecological with economic incentives. It is the proposed cutting of trees, above all, that has made restoration extremely controversial in many places. Forest restoration, then, is not simply a matter of understanding ecology. The authors of this volume explore both the ecological reasons for and effects of restoration and the controversies attending it. Managers should be aware of both.

Restoration seeks to treat the causes of declining ecosystem health, rather than the symptoms. But it is no panacea. It cannot fix all the problems of our forests, and restoration in its strictest sense may not be compatible with desired resource conditions and uses in many circumstances. It is not a one-time solution. Initial thinning and prescribed fire treatments will need to be followed by other prescribed fires, perhaps further thinning, and perhaps seeding or replanting of native vegetation or eradication of nonnative plants.

In the backcountry it may be possible to restore something like a natural fire regime, in which lightning-caused fires will be free to burn where they will at low intensities. Fragmentation and heavy development will make that impossible in many places, though. Near developed areas restoration cannot result in a hands-off management strategy, as it will likely be necessary to conduct ongoing forest maintenance through prescribed burning. Perhaps we may be able to gauge the growing maturity of our land management techniques by the extent to which we are able to align restoration practice with our other requirements of the land, keeping in mind that cultural practices and ecological processes can be mutually reinforcing (SER 2002).

We should also be careful about terminology. Fueled by intensive political interest and high levels of funding for fire protection and prevention, the rhetoric of forest management is rife today with jingoistic talk of restoration that is not ecological restoration. The revegetation of severely burned areas, for example, is not restoration; it is more akin to reclamation —an attempt to avert severe erosion of soil and ensuing degradation of the land. Such treatments do not seek to rapidly restore the structure and function of the original forest. Thinning treatments that seek only to remove some small-diameter trees in order to reduce fire danger are not restoration, for they fail to give sufficient attention to the restoration of grass and wildflower understories, the foundation of most of the biological diversity in these ecosystems. Treatments that are not linked with frequent, low-intensity burning will fail to restore what is certainly a keystone process in these ecosystems. Further, the lack of frequent fire may result in a renewed need for thinning in the future, without any of the benefits of restoration of understory vegetation. The removal of old-growth pines is emphatically not restoration, for numbers of old trees have declined throughout ponderosa pine forests. These old-growth trees are the very trees that restoration seeks to protect and reinvigorate.

Forest restoration focuses on returning low-level fire to its core role, and on protecting the oldest trees and promoting the growth and development of new generations of old trees. It also must consider other native plant species besides pine trees; it must consider restoration of native wildlife composition and densities; it must consider nutrient cycling and hydrology; it must address concerns about invasive species. For it to succeed at meaningful landscape scales it must also be linked to work such as the removal of roads and the restoration of springs, wet meadows, and open, grassy parklands, most of which are severely degraded throughout the Southwest. Finally, if it is to become a lasting part of the social landscape, restoration must benefit and sustain human communities.

Given this complexity, it is no wonder that there has been and will continue to be a tension between those who focus on the dangers from large-scale fire and hence advocate for large-scale restoration, implemented swiftly, and those who would take a slower approach. The brakes on restoration are many. If restoration presents all the promise of a broad, interdisciplinary endeavor that uses a wide range of human capabilities, it is also—for many of the same reasons—fraught with difficulty. Residents often oppose prescribed burns. Some environmentalists, concerned about potential profiteering by a reestablished wood products industry, oppose commercial thinning treatments. Land managers face bureaucratic inertia, red tape, and litigation that can delay projects for years—sometimes for so long that conditions change sufficiently so that the entire inventory, project planning, and environmental review process becomes outdated and must be begun again, causing a lack of follow-through to implementation that stifles the creativity and flexibility needed to conduct restoration. Congress continues to appropriate far more funding for fire suppression than for restoration treatments that will ultimately (but often not immediately) reduce suppression costs. Many rural communities and workers lack the capital, equipment, and skills needed to carry out the needed work. Markets for the small-diameter timber removed from thinned forests often do not exist, necessitating public funding for thinning. This volume, by synthesizing much of what is known about key aspects of ecological restoration in ponderosa pine, may begin to address some of these problems.

How might we measure the success of restoration treatments? In addition to general guidelines given elsewhere (SER 2002) we might consider some specific criteria. In the short term, success will be measured largely by a reduced risk of large-scale high-intensity fires. In the long term, it will be measured by answers to more complex questions such as these:

Do restoration treatments restore natural patterns and processes?

Do they create a self-sustaining matrix?

Do they facilitate sustainable regeneration of ponderosa pine and other plants?

Does the resulting habitat matrix support diverse plants and wildlife within the natural range of variability?

Do they accommodate climate shifts and changes, whether cyclical or not?

In the end, the success of forest restoration will depend on the degree to which human beings over many decades agree to work with, rather than against, the natural processes that have created these forests.

Restoration entails difficult choices, but working toward it should itself not be a difficult choice. Not implementing restoration is an option, but not a good one. As a recent book puts it, Simply leaving today’s forests alone after a century of fire suppression and forestry focused on extraction of big trees is not caring for them; it is abandonment (Arno and Allison-Bunnell 2002). To abandon our forests in this way will result in burned-out and depauperate landscapes that will support a less diverse array of plants and animals, and a more limited range of human uses, than today’s. To carefully conduct restoration treatments on a large scale, on the other hand, and to do so not just around human settlements but across the broader landscape, will protect ecologically important areas and help ensure that our forests provide a broad range of habitats and ecological values for generations to come. Only that management choice will be equitable to future human generations and to our forest surroundings themselves.

A few notes about this book’s scope, organization, and terminology. The region this book focuses on includes Arizona, New Mexico, and the southern portions of Utah and Colorado. The majority of the scientific research profiled here has been conducted in northern Arizona, but managers working elsewhere are also likely to find much of interest here. Indeed, restorationists working in entirely different ecosystems have faced many of the same difficulties arising from social contexts that are profiled in this book. The book is intended to become part of an evolving conversation about ecological restoration as a whole as it is carried on throughout the world.

Ecologically, though, this book is only about ponderosa pine forests. All too often discussions of western forest health suffer from the unwarranted lumping-together of forest types that are ecologically very different. Restoration of, say, southwestern mixed-conifer forests or piñon-juniper woodlands may well be warranted, but the scientific basis for such activities is not the same as that in this volume. Some of the general principles described may be widely applicable, but this book does not summarize information in such a way that it may be applied uncritically to other forest types.

Nor does it present a single approach at all. The book does not call for any single restoration prescription, especially not any one thinning prescription. Decisions about how to conduct restoration must always be made on a local basis. They must be based both on a scientific understanding of local ecological conditions and on consideration of other factors. Those planning and implementing restoration projects typically must consider ecological, social, and economic perspectives as they do their work. Still, this book is mainly based on ecological and natural resource science, and for that reason the limitations of science are given more consideration in the book than, say, the limitations of politics, economics, or previous forest management paradigms. Such critiques are readily available elsewhere.

The book is organized into four sections that sequentially narrow the field of restoration from the general to the specific. The first lays out the overall context—ecological, social, economic, political, and philosophical—for restoration. The contributors to this section hail from a variety of disciplines and speak with diverse voices that epitomize the diversity of views about restoration. The second section focuses on how important ecosystem processes such as fire, hydrology, and nutrient cycling are affected by restoration activities. The third section goes into detail in assessing treatment effects on such specific ecosystem components as trees, understory plants, animals, and rare or invasive species. The fourth section looks at the details of implementing restoration projects by examining such topics as smoke management, the protection of cultural resources, monitoring, and other issues. Each section is introduced with a case study that demonstrates some of the promise and pitfalls of ongoing restoration projects.

Finally, some points on terminology. The contributors generally refer to forest tracts that have been the subject of recent restoration work as treated, as opposed to untreated. Restoration is a long-term process, and a tract that has been thinned and subsequently burned once cannot yet be considered restored—rather, it is perhaps more appropriate to state that it has been set on a restoration trajectory. Authors also use the term presettlement to refer to forests as they were before the onset of Euro-American settlement—not out of any desire to deny the effects indigenous peoples had on forest structure over many years, but simply because it is less awkward than the term pre-Euro-American settlement. Collectively, our vision is that restoration will draw on the region’s long human history in returning forests and people to a working relationship that enriches both.

PART I

The Context for Restoration

Ecological restoration has as its goals the preservation of biodiversity, the health and maintenance of sustainable ecosystems, and the development of mutually beneficial relationships between humans and nature. In some instances, though, it is perceived as a specialized endeavor that remains primarily of interest to its practitioners—something yet to be fully understood by society’s mainstream. In southwestern ponderosa pine forests, restoration is more than this. Ecological restoration of these forests is intimately tied to human well-being, and is of concern to wide segments of society. Many southwestern forests that are ecologically unhealthy are also uncommonly prone to dangerous, high-intensity fires. Restoration has the potential to simultaneously return ecological integrity and reduce the risk of such fires. As described in Chapter 1, a large-scale restoration project in Flagstaff, Arizona, was designed precisely with those goals in mind.

But Chapter 1 also shows that these efforts can be controversial and difficult to implement. Why should this be so? It is not, for the most part, any failing of science. Wally Covington, in Chapter 2, demonstrates that the ecological functioning of these forests (Figure I.1) is fairly well understood. An arid climate and long-lived trees have allowed researchers, through the study of tree rings and other physical evidence, to reconstruct forest history in great detail. In many cases we know what their structure once was; we know how often they burned; we know to what extent such disturbances were correlated with climate cycles or aspects of human history; we know how long their trees lived. We also know how they have changed since the advent of modern, Western civilization. To a remarkable extent we know what these forests were like, in other words, in the period immediately preceding Euro-American settlement, the last period during which processes that shaped these ecosystems over evolutionary time remained intact. Soon after Euro-American settlement, novel cultural practices such as heavy livestock grazing and fire suppression were introduced, with severe impacts on forest structures and ecological processes.

Of course, any study of physical reference materials is inevitably limited. As Thom Alcoze shows in Chapter 3, the dendrochronological record does not clearly reveal to what extent indigenous peoples altered fire regimes in southwestern ponderosa pine forests, but native peoples and nonhuman forces do appear to have worked in ecological concert; fires caused by people and by lightning, in other words, had similar ecological effects. It is beyond the scope of this book to argue whether this was due to low population numbers, limited technologies, or particular worldviews; the important point is that prior to the arrival of Euro-Americans, human influences on the ecology of southwestern ponderosa pine forests appear to have remained well within what has been labeled their historic range of variation.

e9781597262965_i0003.jpg

Figure I.1. Powell Plateau, Grand Canyon National Park, northern Arizona. Widely spaced pines and a well-developed herbaceous understory constitute conditions that were once widespread but are now rare in southwestern ponderosa pine forests. Photograph by Doc Smith/Ecological Restoration Institute.

Chapter 2 discusses the evolutionary context of southwestern pine forests and reviews the enormous changes that have taken place since the arrival of Euro-Americans. Though logging has had the most visible short-term effect on forest structure, it can be argued that livestock grazing and fire suppression have had more insidious long-term effects, since they have fundamentally altered forest processes . Today, though primary resource exploitation plays a relatively minor role in the economy of the Southwest, the pressures of human uses on these forests have grown and will likely continue to grow in manifold ways, complicating the planning and implementation of restoration treatments or of any other management strategy.

Restoration has the potential to solve some, though certainly not all, of the problems current forest managers face. And science certainly has a primary role to play in informing restoration decisions. But it is important to note that many past decisions that helped create today’s forest conditions—such as the suppression of wildfires—were also informed by scientific understanding. How is restoration ecology different from past science? Why should we trust it?

A partial answer is this: Unlike many past uses of science, restoration ecology is not driven by economics. As P. J. Daugherty and Gary Snider write in Chapter 4, it may dovetail both with the wish to protect human habitations from wildfire and in some cases with commercial activities, but it does not exist for those reasons. It may eventually produce economic payoffs in the form of reduced fire-fighting expenditures, but in the short term society will have to pay to implement it. Restoration does not, unlike many traditional management practices, seek profits by extracting resources more quickly than the ecosystem can sustainably produce them. It seeks to work with natural processes, rather than against them.

The science of restoration ecology also cannot be divorced from its social context. Restoration is not and cannot be just about ecology. It is intimately tied to the sorts of economic decisions that have played a role in bringing the forests to their current degraded condition (Chapter 4); it is an artifact of the decision-making processes that shape a democratic society (Chapter 5); and it is linked to the ways in which human beings see the world and define their social roles (Chapter 6). Restoration, then, is not just a matter of refining our ecological knowledge and using it to inform management decisions. It is a matter of redefining relationships both among human beings and between humans and nature. It will succeed only if, as Daugherty and Snider argue, economic relationships are forged that value sustainable, multigenerational human links to our natural surroundings; if decisions are reached, as Hanna Cortner argues, through truly democratic and inclusive processes; and if all participants in these forests, as Max Oelschlaeger argues, see themselves as part—but only as a part—of what he terms the larger forest story.

Compromise on all sides would seem to be in order. If restoration is to succeed on a large scale, across the landscape, loggers will have to accept the reality that any sustainable forest industry in the Southwest must be based on the harvest of small, rather than large, trees; environmentalists will have to accept that, whatever the sorry story of human intervention in the last century, there is a role for people in the ecology of the region’s forests; agency officials will have to accept that their decisions must be made with a full range of truly meaningful public input; scientists will have to accept that their findings alone are not sufficient for informed decision-making. It will be the better part of wisdom if we all can accept that such compromises, which might at first appear to be limitations, are really strengths: they argue for an intimate, thoughtful, and mutualistic relationship between people, other members of the community of organisms, and their natural surroundings. These are not matters for ecologists or for professional land managers alone; they are matters for us all.

Chapter 1

The Flagstaff Model

PETER FRIEDERICI

Flagstaff, Arizona, a rapidly growing city of more than 50,000, is nestled in the largest ponderosa pine forest in the world, a swath of trees that extends from western New Mexico to north-central Arizona. The sharp-edged San Francisco Peaks, thickly cloaked with pine, fir, spruce, and aspen, rise high on the northern skyline. It’s a beautiful setting, but also a flammable one. Several times in recent years large wildfires have cast palls of smoke over the city and made residents cognizant of the danger inherent in living in a fire-prone forest.

It is because the residents of Flagstaff both love their trees and fear wildfires that they have launched an ambitious campaign to restore the surrounding forest. This effort is being closely watched in other communities because of the controversy it has engendered, and because federal officials have pointed to the Flagstaff Model as a template for cooperative restoration efforts elsewhere (Jehl 2000). The primary focus of restoration activities in the Flagstaff area is the Greater Flagstaff Forests Partnership (GFFP), a collaborative effort that has as its goal the restoration of 100,000 acres (40,000 hectares) of forest ringing the city. It is an ambitious plan that illustrates both the potential for forest restoration and its pitfalls, and that raises questions highly applicable to restorationists elsewhere, especially: if this is such a good idea, why is it so hard to implement?

The Finest Timber in the World

Flagstaff is an appropriate hub of forest restoration, since the extractive excesses that have altered southwestern forests were unbridled here. As Euro-American settlement of northern Arizona began in the 1870s, the area’s resources were rich and accessible. Ponderosa pine trees towered over bunchgrasses in open, sunny forests. Old trees developed conspicuous yellow bark and grew to a meter and more in diameter. In 1876 one visitor, George Brewer, wrote that these so-called yellow pines constituted a very extensive belt of the finest timber in the world contiguous to the city’s site (Cline 1976).

In 1882 Flagstaff’s first sawmill opened, with the primary purpose of producing supplies for the new transcontinental Atlantic & Pacific Railroad. The rails allowed easy shipping, and in 1883 alone the mill produced 20 million board feet (47,200 square meters) of what was described as magnificent clear lumber (Hamilton 1884) and shipped as far east as New York (Ashworth 1991). Other sawmills followed, and logging of old-growth pines (Figure 1.1) continued as a significant industry into the late twentieth century.

Logging was conducted through clearcutting in the early days, and entire mile-square sections were laid bare (Ashworth 1991; Menzel and Covington 1997). Even after the San Francisco Mountain Forest Reserve, a forerunner of northern Arizona’s national forests, was established in 1898, with regulations requiring the retention of seed trees, few old trees were left. On Woody Mountain, southwest of Flagstaff, loggers cut an estimated 3,000 to 4,000 pines with an average diameter at breast height (dbh) of 20 inches (51 centimeters) in 1904, and on more than 450 acres (180 hectares) left only 64 seed trees (Ashworth 1991). In 1904 a United States Geological Survey report predicted that the area’s [c]losely logged lands will not again bear a forest equal to the one cut off during the next 220 to 250 years (Leiburg et al. 1904).

e9781597262965_i0004.jpg

Figure 1.1. Getting out the yellow pines: logging near Flagstaff, circa 1926. Photograph courtesy of Arizona Historical Society/Northern Arizona Division, AHS.0688.00004.

Newcomers also quickly took advantage of what one explorer called the region’s luxuriant and abundant bunchgrasses (Beale 1858). By 1887 an estimated 200,000 sheep grazed the San Francisco Peaks area (Cline 1976). Ranchers imported huge herds of cattle, and by 1888 a Prescott newspaper reported that many portions of the [Arizona] Territory are now overstocked to an alarming extent (Cline 1976). Severe drought in 1891 and 1892 killed livestock in droves. Ranchers went broke, and long-term damage was done to rangelands around Flagstaff, across northern Arizona, and throughout the Southwest (Leiburg et al. 1904; Baker et al. 1988; Abruzzi 1995). Cattle and to a lesser extent sheep grazing continue at a much smaller scale today.

Wildlife populations also changed dramatically. Grizzly bears (Ursus arctos horribilis) and gray wolves (Canis lupus) were extirpated in the first half of the twentieth century. Merriam’s elk (Cervus elaphus merriami), which were scarce or absent during the nineteenth century, were driven to extinction early on (Davis 1982); Rocky Mountain elk (C. e. nelsoni), a different subspecies, were introduced in the first half of the twentieth century and have proliferated; pronghorn (Antilocapra americana), meanwhile, have grown much scarcer (Davis 1982). Heavy grazing and browsing by elk and mule deer (Odocoileus hemionus) have almost certainly helped alter the forest’s herbaceous understory.

The area’s forests changed quickly. Tree-ring analysis has shown that pines in Fort Valley, 10 miles northwest of Flagstaff, burned at average intervals of between 4.4 and 17 years (Dieterich 1980), consistent with the 2- to 8-year fire interval found at many sites in northern Arizona (Moore et al. 1999). These fires raced through the flammable grasses and killed some small trees but rarely burned the crowns of large pines (Woolsey 1911; Cooper 1960). The last significant fire in Fort Valley, as in Walnut Canyon just east of Flagstaff, was recorded in 1876 (Dieterich 1980; Swetnam et al. 1990); the last at Camp Navajo west of Flagstaff occurred in 1883 (Fulé et al. 1997). Logging slash fueled fires even in logged areas, though, and as early as 1885 loggers and sawmill crews were sent to fight forest fires near Flagstaff (Ashworth 1991), while Forest Service firefighters were organized in the early twentieth century.

By the beginning of the twentieth century, concerns about deforestation and overgrazing had grown. The establishment of forest reserves and the U.S. Forest Service was one result; so was the beginning of a more rigorous forest science. In 1908 forester Gus Pearson helped found the first forest experiment station on federal land in Fort Valley. With Theodore Woolsey, he also established permanent forest plots in northern Arizona and New Mexico, to be remeasured at five-year intervals (Woolsey 1911).

Pearson’s first assignment was to ascertain why ponderosa pine was not reproducing in cutover areas: partly, he found, because loggers had left few seed trees, and partly because in the Southwest few years are wet enough to allow widespread survival of ponderosa seedlings. He and other foresters were relieved when one such year came in 1919 (Pearson 1923). Growing conditions that year were further enhanced by a grazing-induced lack of competition from grasses, and by a lack of low-level fires that might have killed seedlings.

The cumulative result of these changes was profound. Within a century the forest around Flagstaff was first open and composed largely of big pines and bunchgrasses; then denuded of large trees and severely overgrazed; and finally composed primarily of dense thickets of young pines, many of them established in 1919. A typical example is close at hand to the experimental station Pearson established. In the Gus Pearson Natural Area, an unlogged stand whose trees have been measured at five-year intervals since 1920, a reconstruction of 1876 forest conditions conducted in the 1990s resulted in striking comparisons (Covington et al. 1997). Where an average of 22.8 pines per acre (56 per hectare) had grown in small clumps in 1876, more than 1,250 per acre (3,000 per hectare) grew in continuous stands in the 1990s. More than 98 percent were smaller than 16 inches (40 centimeters) in diameter, and many formed dense doghair thickets of small trees. Buried in accumulated dead needles, the forest floor supported scant understory vegetation.

Throughout the region large, old yellow pines have become rare, and some that remain are dying at increased rates due to competition with abundant younger trees (Mast et al. 1999). By the 1970s foresters were concerned enough about these forest changes to conduct experimental treatments aimed at thinning dense forests. Some used fire alone. In Fort Valley Jack Dieterich and Stephen Sackett of the Forest Service and Wally Covington of Northern Arizona University (NAU) implemented a series of low-level prescribed fires that inadvertently killed many old-growth pines whose roots were baked when thick blankets of duff around their trunks burned; younger trees, lacking that duff, tended to survive (Covington and Sackett 1984; Sackett et al. 1996). Simply returning fire to the forests around Flagstaff, it appeared, would not thin them sufficiently of small trees, and might kill big trees—and it was dangerous, since any fire in the fuel-rich forests could become a conflagration.

A Pioneering Partnership

To area residents, the most significant ecological change has been the increased fire danger resulting from increased fuel loads. According to figures compiled by the Coconino National Forest, all ten of the largest wildfires in the forest’s history have occurred since 1970 (GFFP 2001; Figure 2.5). Both the number and the acreage of large wildfires have increased, and so has the percentage of area burned in which fires burned so hot that they destroyed entire stands. The year 1996 was a particularly devastating year, as more than 25,000 acres (10,000 hectares) burned just northwest of Flagstaff. Over $6.2 million was spent battling those blazes.

Such wildfires have caused extensive ecological damage. Soils on steep slopes have eroded; invasive plants have spread widely into burned areas; territories occupied by such species as Mexican spotted owls and northern goshawks have been burned so severely that they have become uninhabitable by those species. But the driving concern remained fire danger to human lives and property.

The result of these concerns was the establishment of the Grand Canyon Forests Partnership in 1996 (the name was changed to Greater Flagstaff Forests Partnership in 2002). By then most logging in the area had been discontinued due to a lack of large trees, environmental concerns, and unfavorable market conditions (Nijhuis 1999). The Coconino National Forest and city of Flagstaff had already conducted limited thinning in and near the city to reduce fuel loads and fire danger. Researchers from NAU had conducted a restoration experiment at the Gus Pearson Natural Area that had shown how trees, understory, and soil responded when a dense stand was thinned and then burned (Covington et al. 1997); many of the results from that experiment are summarized in this book. The partnership aimed to do this on a much larger scale, setting as its goal the treatment of 100,000 acres (40,000 hectares) of national forest land around the city in ten years (Figure 1.2). It hoped to accomplish this in a way that was economically sustainable and socially equitable.

The partnership was set up as a formal collaboration between the newly formed, nonprofit Greater Flagstaff Forests Foundation (GFFF) and the Forest Service. The foundation, under the guidance of an advisory board, would recommend restoration activities to the Forest Service, and would implement much of the work itself by contracting with loggers. It would raise some of the money for its work by selling wood from thinned forests. The Forest Service retained decision-making power and would prepare environmental assessments. Because the GFFP was formally recognized by the federal government as a reinvention laboratory, the Forest Service was permitted to waive certain policies and regulations, but not laws, in preparing treatments.

The advisory board included representatives from land management agencies, the U.S. Fish and Wildlife Service, the Arizona Game and Fish Department, the Grand Canyon Trust (a regional environmental group), the Flagstaff Fire Department, The Nature Conservancy, various departments of NAU, and others. The partnership hoped to restore natural ecosystem functions, especially fire, in a sustainable manner. In doing so, it would reduce the risk of large fires. It would also test a variety of restoration approaches—ecological, operational, economic, and social. In some places it would implement full-scale forest restoration; in others, driven by aesthetic, social, wildlife, or other concerns, it would limit its work to fuel reduction. In restoration areas it would try to control noxious weeds, close and revegetate unnecessary roads, and restore native grasses and other herbaceous plants. Its goal was not to return the forest to its precise condition before Euro-American settlement, but to restore ecological processes that would allow the forest to sustain itself. The partnership delineated its purpose in a detailed mission statement that outlined the ideals of ecology, community collaboration, and economy it hoped would be realized by 2020 (Boxes 1.1–1.3).

Realizing that mission, though, was fraught with difficulty. The trouble began in 1998, when the partnership designated Fort