ABOUT ISLAND PRESS Island Press, a nonprofit organization, publishes, markets, and dis tributes the most advanced thinking on the conservation of our natural resources-books about soil, land, water, forests, wildlife, and hazardous and toxic wastes. These books are practical tools used by public officials, business and industry leaders, natural re source managers, and concerned citizens working to solve both local and global resource problems. Founded in 1978, Island Press reorganized in 1984 to meet the increasing demand for substantive books on all resource-related issues. Island Press publishes and distributes under its own imprint and offers these services to other nonprofit organizations. Support for Island Press is provided by The Geraldine R. Dodge Foundation, The Energy Foundation, The Charles Engelhard Foun dation, The Ford Foundation, Glen Eagles Foundation, The George Gund Foundation, William and Flora Hewlett Foundation, The James Irvine Foundation, The John D. and Catherine T. MacArthur Foundation, The Andrew W. Mellon Foundation, The Joyce Mertz Gilmore Foundation, The New-Land Foundation, The Pew Charit able Trusts, The Rockefeller Brothers Fund, The Tides Foundation, and individual donors. FIRE ECOLOGY OF PACIFIC NORTHWEST FORESTS FIRE ECOLOGY OF PACIFIC NORTHWEST FORESTS James Agee J(. WASHINGTON, D.C. 0 COVELO, CALIFORNIA Copyright © 1993 by James K. Agee 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, Suite 300, 1718 Connecticut Avenue, NW, Washington, DC 20009. ISLAND PRESS is a trademark of The Center for Resource Economics. The author is grateful for permission to include the following previously copyrighted materials in redrafted form, except where noted: Figures 4. 5 and 11.11 are from Forest Ecology and Management, Elsevier Science Publishers BV. Figure 5.5 is courtesy of Yale University. Figures 4.19, 7. 7, and 10.12 are from Ecology, and Figure 11.4 is from Ecological Monographs, published by the Ecological Society of America. Figures 10.5 and 10.11 are from Northwest Science, published by Washington State University Press. Figure 11.2 is from the Journal of Forestry, published by the Society of American Foresters. Figure 11.5 is original artwork from Scientific American, published by Scientific American, Inc. Figure 12.11 is from the Journal of Range Management, published by the Society for Range Management. Library of Congress Cataloging-in-Publication Data Agee. James K. Fire ecology of Pacific Northwest forests I James K. Agee. p. em. Includes bibliographical references (p. ) and index. ISBN 1-55963-230-5 l. Forest management-Northwest, Pacific. 2. Fire ecology-Northwest, Pacific. 3. Forest fires-Environmental aspects-Northwest Pacific. I. Title. SD144.Al3A55 1993 574.5'264-dc20 93-2071 CIP Printed on recycled, acid-free paper. Manufactured in the United States of America 10 9 8 This book is dedicated to my parents, Carroll and Lee Agee, who supported a young boy's dream to learn about forests, and to Professor Harold BiswelL pioneer fire ecologist, who helped the dream come true. CONTENTS PREFACE xi ACKNOWLEDGMENTS xiii 1. THE NATURAL FIRE REGIME 3 2. THE NATURAL FIRE ENVIRONMENT 25 3. THE CULTURAL FIRE ENVIRONMENT 53 4. METHODS FOR FIRE HISTORY 75 5. FIRE EFFECTS ON VEGETATION 113 6. ENVIRONMENTAL EFFECTS OF FIRE 151 7. SITKA SPRUCE, CoAST REDWOOD, AND WESTERN HEMLOCK FORESTS 187 8. PACIFIC SILVER FIR AND RED FIR FORESTS 226 9. SuBALPINE EcosYSTEMS 250 10. MIXED-CONIFER/MixED-EVERGREEN FORESTS 280 11. PONDEROSA PINE AND LODGEPOLE PINE FORESTS 320 12. NORTHWEST WOODLANDS 351 13. FIRE IN OuR FuTURE 386 APPENDIX A. COMMON CONVERSION FACTORS 409 APPENDIX B. NAMES OF PLANTS MENTIONED IN TEXT 411 GLOSSARY 417 REFERENCES 421 477 INDEX ix