National Academies Press: OpenBook
Suggested Citation:"Front Matter." National Research Council. 2002. Predicting Invasions of Nonindigenous Plants and Plant Pests. Washington, DC: The National Academies Press. doi: 10.17226/10259.
×

PREDICTING INVASIONS OF NONINDIGENOUS PLANTS AND PLANT PESTS

Committee on the Scientific Basis for Predicting the Invasive Potential of Nonindigenous Plants and Plant Pests in the United States

Board on Agriculture and Natural Resources

Board on Life Sciences

Division on Earth and Life Studies

National Research Council

NATIONAL ACADEMY PRESS
Washington, D.C.

Suggested Citation:"Front Matter." National Research Council. 2002. Predicting Invasions of Nonindigenous Plants and Plant Pests. Washington, DC: The National Academies Press. doi: 10.17226/10259.
×

NATIONAL ACADEMY PRESS
2101 Constitution Avenue, NW Washington, D.C. 20418

NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competences and with regard for appropriate balance.

This study was supported by Grant No. 00-8100-0518-GR from the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service (APHIS), Plant Protection and Quarantine. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the views of the organizations or agencies that provided support for the project.

Library of Congress Cataloging-in-Publication Data

Predicting invasions of nonindigenous plants and plant pests.

p. cm.

“Committee on the Scientific Basis for Predicting the Invasive Potential of Nonindigenous Plants and Plant Pests in the United States.”

Includes bibliographical references and index.

ISBN 0-309-08264-1 (hardcover)

1. Nonindigenous pests—Control—United States. 2. Invasive plants—Control—United States. 3. Biological invasions—United States—Prevention. 4. Plant invasions—United States—Prevention. I. National Academy Press (U.S.) II. National Research Council. Committee on the Scientific Basis for Predicting the Invasive Potential of Nonindigenous Plants and Plant Pests in the United States.

SB990.5.U6 P74 2002

632'.5—dc21

2002003344

Additional copies of this report are available from
National Academy Press,
2101 Constitution Avenue, N.W., Lockbox 285, Washington, D.C. 20055; (800) 624-6242 or (202) 334-3313 (in the Washington metropolitan area); Internet, http://www.nap.edu

Cover: Clockwise, from top left: Larvae of Asian long-horned beetle (Anoplophora glabripennis) in wood, USDA Forest Service. Dead American chesnut (Castanea dentata), spores of fungus Cryphonectria parasitica in background, William MacDonald, West Virginia University. Hemlock woolly adelgid (Adelges tsugae Annand), Kathleen Shields, USDA Forest Service. Fountain grass (Pennisetum setaceum), Richard Mack, Washington State University.

Printed in the United States of America

Copyright 2002 by the National Academy of Sciences. All rights reserved.

Suggested Citation:"Front Matter." National Research Council. 2002. Predicting Invasions of Nonindigenous Plants and Plant Pests. Washington, DC: The National Academies Press. doi: 10.17226/10259.
×

THE NATIONAL ACADEMIES

National Academy of Sciences

National Academy of Engineering

Institute of Medicine

National Research Council

The National Academy of Sciences is a private, nonprofit, self-perpetuating society of distinguished scholars engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare. Upon the authority of the charter granted tit by the Congress in 1863, the Academy has a mandate that requires it to advise the federal government on scientific and technical matters. Dr. Bruce M. Alberts is president of the National Academy of Sciences.

The National Academy of Engineering was established in 1964, under the charter of the National Academy of Sciences, as a parallel organization of outstanding engineers. It is autonomous in its administration and in the selection of its members, sharing with the National Academy of Sciences the responsibility for advising the federal government. The National Academy of Engineering also sponsors engineering programs aimed at meeting national needs, encourages education and research, and recognizes the superior achievements of engineers. Dr. Wm. A. Wulf is president of the National Academy of Engineering.

The Institute of Medicine was established in 1970 by the National Academy of Sciences to secure the services of eminent members of appropriate professions in the examination of policy matters pertaining to the health of the public. The Institute acts under the responsibility given to the National Academy of Sciences by its congressional charter to be an adviser to the federal government and, upon its own initiative, to identify issues of medical care, research, and education. Dr. Kenneth I. Shine is president of the Institute of Medicine.

The National Research Council was organized by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy’s purposes of furthering knowledge and advising the federal government. Functioning in accordance with general policies determined by the Academy, the Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in providing services to the government, the public, and the scientific and engineering communities. The Council is administered jointly by both Academies and the Institute of Medicine. Dr. Bruce M. Alberts and Dr. Wm. A. Wulf are chairman and vice chairman, respectively, of the National Research Council.

Suggested Citation:"Front Matter." National Research Council. 2002. Predicting Invasions of Nonindigenous Plants and Plant Pests. Washington, DC: The National Academies Press. doi: 10.17226/10259.
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Suggested Citation:"Front Matter." National Research Council. 2002. Predicting Invasions of Nonindigenous Plants and Plant Pests. Washington, DC: The National Academies Press. doi: 10.17226/10259.
×

COMMITTEE ON THE SCIENTIFIC BASIS FOR PREDICTING THE INVASIVE POTENTIAL OF NONINDIGENOUS PLANTS AND PLANT PESTS IN THE UNITED STATES

RICHARD N. MACK, Chair,

Washington State University

SPENCER C. H. BARRETT,

University of Toronto

PETER L. DEFUR,

Virginia Commonwealth University

WILLIAM L. MACDONALD,

West Virginia University

LAURENCE VINCENT MADDEN,

The Ohio State University

DAVID S. MARSHALL,

Texas A&M University

DEBORAH G. MCCULLOUGH,

Michigan State University

PETER B. MCEVOY,

Oregon State University

JAN P. NYROP,

Cornell University

SARAH ELIZABETH HAYDEN REICHARD,

University of Washington

KEVIN J. RICE,

University of California, Davis

SUE A. TOLIN,

Virginia Polytechnic Institute and State University

Staff

ROBIN SCHOEN, Project Director

LUCYNA K. KURTYKA, Project Officer

KAREN L. IMHOF, Project Assistant

NORMAN GROSSBLATT, Editor

Suggested Citation:"Front Matter." National Research Council. 2002. Predicting Invasions of Nonindigenous Plants and Plant Pests. Washington, DC: The National Academies Press. doi: 10.17226/10259.
×

BOARD ON AGRICULTURE AND NATURAL RESOURCES NATIONAL RESEARCH COUNCIL

HARLEY W. MOON, Chair,

Iowa State University

CORNELIA B. FLORA,

Iowa State University

ROBERT B. FRIDLEY,

University of California, Davis

BARBARA P. GLENN,

Federation of Animal Science Societies, Bethesda, Maryland

W.R. (REG) GOMES,

University of California, Oakland

LINDA F. GOLODNER,

National Consumers League, Washington, D.C.

PERRY R. HAGENSTEIN,

Institute for Forest Analysis, Planning, and Policy, Wayland, Massachusetts

GEORGE R. HALLBERG,

The Cadmus Group, Inc., Waltham, Massachusetts

CALESTOUS JUMA,

Harvard University

GILBERT A. LEVEILLE,

McNeil Consumer Healthcare, Denville, New Jersey

WHITNEY MACMILLAN,

Cargill, Inc., Minneapolis, Minnesota (retired)

TERRY L. MEDLEY,

DuPont Biosolutions Enterprise, Wilmington, Delaware

WILLIAM L. OGREN,

U.S. Department of Agriculture (retired)

ALICE N. PELL,

Cornell University

NANCY J. RACHMAN,

Novigen Sciences, Inc., Washington, D.C.

G. EDWARD SCHUH,

University of Minnesota

BRIAN J. STASKAWICZ,

University of California, Berkeley

JOHN W. SUTTIE,

University of Wisconsin, Madison

JAMES H. TUMLINSON, III,

U.S. Department of Agriculture, Agricultural Research Service

JAMES J. ZUICHES,

Washington State University

Staff

CHARLOTTE KIRK BAER, Director

JULIE ANDREWS, Senior Project Assistant

Suggested Citation:"Front Matter." National Research Council. 2002. Predicting Invasions of Nonindigenous Plants and Plant Pests. Washington, DC: The National Academies Press. doi: 10.17226/10259.
×

BOARD ON LIFE SCIENCES

COREY S. GOODMAN, (Chair)

University of California, Berkeley, California

MICHAEL T. CLEGG,

University of California, Riverside, California

DAVID S. EISENBERG,

University of California, Los Angeles, California

DAVID J. GALAS,

Keck Graduate Institute of Applied Life Science, Claremont, California

BARBARA GASTEL,

Texas A&M University, College Station, Texas

JAMES M. GENTILE,

Hope College, Holland, Michigan

DAVID V. GOEDDEL,

Tularik, Inc., South San Francisco, California

ELLIOT M. MEYEROWITZ,

California Institute of Technology, Pasadena, California

ROBERT T. PAINE,

University of Washington, Seattle, Washington

STUART L. PIMM,

Columbia University, New York, New York

JOAN B. ROSE,

University of South Florida, St. Petersburg, Florida

GERALD M. RUBIN,

Howard Hughes Biomedical Research, Chevy Chase, Maryland

RONALD R. SEDEROFF,

North Carolina State University, Raleigh

ROBERT R. SOKAL,

State University of New York, Stony Brook, New York

SHIRLEY M. TILGHMAN,

Princeton University, Princeton, New Jersey

RAYMOND L. WHITE,

DNA Sciences, Inc., Fremont, California

Senior Staff

FRANCES SHARPLES, Director

BRIDGET K.B. AVILA, Senior Project Assistant

Page viii Cite
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Suggested Citation:"Front Matter." National Research Council. 2002. Predicting Invasions of Nonindigenous Plants and Plant Pests. Washington, DC: The National Academies Press. doi: 10.17226/10259.
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Acknowledgments

This report is the product of many individuals. This report has been reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise, in accordance with procedures approved by the NRC’s Report Review Committee. The purpose of this independent review is to provide candid and critical comments that will assist the institution in making its published report as sound as possible and to ensure that the report meets institutional standards for objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process. We wish to thank the following individuals for their review of this report:

MAY R. BERENBAUM, University of Illinois

CHARLOTTE R. BRONSON, Iowa State University

DONALD DAHLSTEN, University of California, Berkeley

JEFF DANGL, University of North Carolina

STUART H. GAGE, Michigan State University

ROBERT P. KAHN, Rockville, Maryland

ANDREW M. LIEBHOLD, US Department of Agriculture, Forest Service, West Virginia

SVATA M. LOUDA, University of Nebraska

KIRK A. MOLONEY, Iowa State University

MARCEL REJMÁNEK, University of California, Davis

DANIEL SIMBERLOFF, University of Tennessee

DONALD L. WYSE, University of Minnesota

Suggested Citation:"Front Matter." National Research Council. 2002. Predicting Invasions of Nonindigenous Plants and Plant Pests. Washington, DC: The National Academies Press. doi: 10.17226/10259.
×

Although the reviewers listed above have provided many constructive comments and suggestions, they were not asked to endorse the conclusions or recommendations nor did they see the final draft of the report before its release. Dr. W.R. Gomes of the University of California oversaw the review of this report. Appointed by the National Research Council, Dr. Gomes was responsible for making certain that an independent examination of this report was carried out in accordance with institutional procedures and that all review comments were carefully considered. Responsibility for the final content of this report rests entirely with the authoring committee and the institution.

Finally, we would like to thank the staff for this project, including Robin Schoen, Study Director, Lucyna Kurtyka, Staff Officer, Karen Imhof, Project Assistant, and Norman Grossblatt, Editor.

Suggested Citation:"Front Matter." National Research Council. 2002. Predicting Invasions of Nonindigenous Plants and Plant Pests. Washington, DC: The National Academies Press. doi: 10.17226/10259.
×

Preface

As the United States faces biological warfare for the first time and ponders the consequences of growing genetically modified crops, a largely unnoticed biological attack is underway; actually, it has been under way for centuries and shows no signs of slowing. Nonindigenous species—animals, plants, and microorganisms occurring beyond their original geographic ranges—are flowing into this country at a remarkable rate. Often unchecked by natural enemies or forces that modulate their numbers, many of these will become invasive pests that threaten human, animal, and plant health. America’s plant resources have been most affected, as foreign plants, arthropods, and plant pathogens attack our crops, gardens, urban treescapes, pastures, rangelands, natural forests, wetlands, prairies, and deserts. From coast to coast, there is hardly a place in the country untouched by invasive nonindigenous species.

In 1999, President Clinton established the National Invasive Species Council, which is composed of the heads of eight federal agencies, to develop a coordinated plan for managing nonindigenous invasive species. By one estimate, the toll of these species in lost crops and the cost of containment measures such as mechanical destruction, and the use of pesticides and biological control—is $137 billion per year. The indirect and ecological costs of losing native species because of attacks by or competition with invasive species may be incalculable. Moreover, while farmers, as caretakers of agricultural lands, have taken action to control pests in their fields, invasions into natural ecosystems have received far less attention; in many cases, there is little attempt to stop what some environmentalists describe as the “biological pollution” devastating our natural areas.

Suggested Citation:"Front Matter." National Research Council. 2002. Predicting Invasions of Nonindigenous Plants and Plant Pests. Washington, DC: The National Academies Press. doi: 10.17226/10259.
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As a result, current estimates of the present and future costs of invasive species are almost certainly low.

The processes that facilitate the damage caused by invasive plants and plant pests once they are here are not well understood, but there is consensus that the increased rate at which these species are being introduced into the United States is the result of growth in trade with other countries and growth in worldwide tourism and travel. The sheer magnitude of those activities makes it virtually impossible to implement adequate systems for detecting known, unwanted plant pests as they arrive in cargo or with passengers at U.S. ports and move across borders. For example, the desire of gardeners and plant-lovers for “exotic” plants has fueled an influx, via mail and other import routes, of the seeds and cuttings of nonindigenous plants whose potential for invasiveness is unmonitored.

As the first line of defense against the entry of harmful nonindigenous species, the Department of Agriculture’s Animal and Plant Health Inspection Service (APHIS) faces an onerous task. The service is “to facilitate exports, imports, and interstate commerce in agricultural products and other commodities that pose a risk of harboring plant pests or noxious weeds in ways that will reduce, to the extent practicable, as determined by the Secretary, the risk of dissemination of plant pests or noxious weeds.” APHIS must operate, therefore, in an environment of competing priorities—one to facilitate trade and the other to protect plant life from the adverse byproducts of trade. Supporters of each of those priorities—for example, importers of foreign produce versus domestic growers or the landscape industry versus the stewards of national parks—place APHIS practices and decisions under close scrutiny.

With resources to conduct spot checks of less than 2% of all incoming shipments at borders, air, and seaports, APHIS cannot reasonably rely on detection to screen out known nonindigenous species that are “hitchhiking” on imports. It must therefore estimate the economic and environmental risks associated with allowing the entry of a foreign commodity or crop. On the basis of such estimates, APHIS has the authority to prohibit imports, but not without yet another hurdle. Its decisions are bound by international trade law to be supported by scientific evidence. Thus, erecting a science-based system to identify potentially harmful nonindigenous plants, pathogens and arthropods has arisen from both national and international mandates. But that requirement places a heavy burden on our current knowledge of organisms and their potential behavior in a novel environment. Of all the factors considered when estimating risk, behavior in a new environment is the one for which the least information is available.

The National Research Council established the Committee on the Scientific Basis for Predicting the Invasive Potential of Nonindigenous Plants and Plant Pests in the United States in response to a request from APHIS to evaluate the state of scientific knowledge about biological invasions and the state of our ability to reliably predict the outcome of an accidental or intentional introduction of a nonindigenous species. Such information is important to APHIS as it makes

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Suggested Citation:"Front Matter." National Research Council. 2002. Predicting Invasions of Nonindigenous Plants and Plant Pests. Washington, DC: The National Academies Press. doi: 10.17226/10259.
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regulatory decisions, and it is critical for our understanding of the behavior of harmful invasive species and of how we might curb their expansion and impact.

The committee was given the charge to

  • Consider the historical record of weed, pathogen, and arthropod invaders, including pathways of their introduction

  • Identify and analyze circumstances that could allow nonindigenous species to become invaders, considering the biotic and abiotic characteristics of potentially affected ecosystems, including agricultural systems, and the characteristics of nonindigenous plants and pests of plants that contribute to their potential invasiveness

  • Determine the extent to which scientific principles and procedures can characterize the invasive potential of nonindigenous pests of plants and the degree of uncertainty intrinsic in such characterizations

  • Identify research that could improve the prediction of invasiveness

This report summarizes the results of the committee’s investigations. Our study was driven by the need to clarify the boundaries of current scientific knowledge and to guide the direction of our national effort to address the future introduction of harmful nonindigenous species.

Richard N. Mack, Chair,

Committee on the Scientific Basis for Predicting the Invasive Potential of Nonindigenous Plants and Plant Pests in the United States

Suggested Citation:"Front Matter." National Research Council. 2002. Predicting Invasions of Nonindigenous Plants and Plant Pests. Washington, DC: The National Academies Press. doi: 10.17226/10259.
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PREDICTING INVASIONS OF NONINDIGENOUS PLANTS AND PLANT PESTS

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Nonindigenous plants and plant pests that find their way to the United States and become invasive can often cause problems. They cost more than $100 billion per year in crop and timber losses plus the expense of herbicides and pesticides. And this figure does not include the costs of invasions in less intensively managed ecosystems such as wetlands.

Nonindigenous Plants and Plant Pests examines this growing problem and offers recommendations for enhancing the science base in this field, improving our detection of potential invaders, and refining our ability to predict their impact.

The book analyzes the factors that shape an invader’s progress through four stages: arriving through one of many possible ports of entry, reaching a threshold of survival, thriving through proliferation and geographic spread, and ultimate impact on the organism’s new environment. The book also reviews approaches to predicting whether a species will become an invader as well as the more complex challenge of predicting and measuring its impact on the environment, a process involving value judgments and risk assessment.

This detailed analysis will be of interest to policymakers, plant scientists, agricultural producers, environmentalists, and public agencies concerned with invasive plant and plant pest species.

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