a

GAO

United States Government Accountability Office

Report to the Chairman, Committee on 

Resources, House of Representatives

April 2006 INVASIVE FOREST 

PESTS

Lessons Learned from 

Three Recent 

Infestations May Aid 

in Managing Future 

Efforts

GAO-06-353
What GAO Found

United States Government Accountability Office

Why GAO Did This Study

Highlights

Accountability Integrity Reliability

April 2006

INVASIVE FOREST PESTS 

Lessons Learned from Three Recent 

Infestations May Aid in Managing Future 

Efforts 

Highlights of GAO-06-353, a report to the 

Chairman, Committee on Resources, 

House of Representatives

Invasive forest pests have seriously

harmed our environment and 

imposed significant costs upon our

economy. The U.S. Department of

Agriculture (USDA) is the lead

agency for responding to forest

pests. This report evaluates the

federal response to three invasive

forest pests—the Asian longhorned

beetle, the emerald ash borer, and 

the pathogen Phytophthora

ramorum (P. ramorum). 

Specifically, GAO describes (1) the

status of efforts to eradicate these

species, (2) the factors affecting 

the success of those efforts, (3) 

overall forest health monitoring 

programs, (4) coordination and 

communication of the three pest

response efforts, and (5) USDA’s 

use of panels of scientific experts 

to aid in the response efforts. 

What GAO Recommends

GAO recommends that the

Secretary of Agriculture (1) expand

efforts to monitor forest health 

conditions to include urban areas,

particularly those deemed high risk 

for potential infestations; (2) 

regularly update and publish 

management plans for pests that

include status information and

funding needs; and (3) implement 

written procedures that broadly 

define when and how to operate

science panels for specific pests. 

USDA did not directly disagree 

with GAO’s recommendations, but

took issue with GAO’s presentation 

of some of the findings that 

supported the recommendations. 

GAO continues to believe that its 

findings fully support the three 

recommendations. 

On the basis of the available evidence, it appears that the Asian longhorned 

beetle will be eradicated in the three states that have infestations, although 

funding reductions have extended the likely completion date. In contrast, 

the emerald ash borer and P. ramorum—the pathogen that causes Sudden 

Oak Death—are likely to continue to infest and damage forest ecosystems in

the Midwest and West Coast, respectively, despite efforts to control them. 

 

The success of the federal responses to these infestations has been affected 

by several factors. First, the unique biological characteristics of each 

species greatly influenced the ability to effectively control them. Second, 

several years elapsed between each pest’s arrival and its discovery, thereby 

giving it time to become established in the environment before control 

programs began. This situation cannot be fixed retroactively, but it could be 

avoided in the future with better monitoring. Third, quarantines have helped 

contain the spread of the pests, but implementation and enforcement have

been difficult. Fourth, the only available method for eradicating these pests 

is to destroy the infested trees and plants—a costly and sometimes 

impractical approach. Lastly, despite budgeting over $420 million on these 

pests, USDA program managers told GAO that funding has not been 

sufficient to fully implement their programs. 

USDA conducts a range of forest health monitoring programs, including a 

pilot project in some urban areas; however, these programs do not provide 

for comprehensive monitoring in urban forests or other locations considered 

at high risk from pest invasions. Monitoring in such areas is important 

because they are common destination points for internationally traded cargo 

that is a frequent pathway for pests. 

Federal and nonfederal stakeholders involved in these efforts told GAO that 

appropriate mechanisms to coordinate response efforts are generally in 

place, although many noted that better coordination among agriculture and 

natural resource agencies would have helped produce a more effective initial 

response. In addition, USDA’s P. ramorum control plan does not fully 

comply with a congressional requirement that it communicate future funding

needs. Furthermore, USDA has not updated plans for the Asian longhorned 

beetle or emerald ash borer to communicate to decision makers or the 

public how it will modify its response efforts in light of fiscal years 2005 and 

2006 funding reductions, and how those reductions have affected the longterm prospects for managing the pests. 

Panels of scientific experts have assisted USDA with each of the three pest 

responses, although GAO and stakeholders have some concerns about how 

they were formed or operated. For example, some stakeholders believed 

that the agency should have convened the panels more frequently and made 

the panel process more open to interested parties. GAO found that USDA 

does not have written procedures for forming and using science panels. 

www.gao.gov/cgi-bin/getrpt?GAO-06-353.

To view the full product, including the scope 

and methodology, click on the link above. 

For more information, contact Robin Nazzaro 

at (202) 512-3841, or nazzaror@gao.gov. 
Page i GAO-06-353 Invasive Forest Pests

Contents

Letter 1

Results in Brief 3

Background 8

Eradicating the Asian Longhorned Beetle Appears Likely, While 

Success on the Emerald Ash Borer and P. ramorum Is Less 

Promising 15

Efforts to Eradicate These Pests Have Been Affected by Several 

Factors 27

Forest Health Monitoring Does Not Adequately Address Urban 

Forests 51

Coordination Problems Caused Concerns among Stakeholders, and 

Communication on the Status of Pest Responses Is Not

Adequate 58

Science Advisory Panels Have Assisted with the Pest Response 

Efforts, but There Are Concerns about How They Were Formed 

and Operated 66

Conclusions 67

Recommendations 68

Agency Comments and Our Evaluation 69

Appendixes

Appendix I: Objectives, Scope, and Methodology 72

Appendix II: Questions from Structured Interview Guide Administered to 

Stakeholders Involved with the Three Pest Response 

Programs 77

Appendix III: Review of Efforts to Control and Eradicate the Asian 

Longhorned Beetle 81

Origin and Potential Impacts of Asian Longhorned Beetle 

Infestations 81

Federal, State, and Local Roles in Controlling and Eradicating the 

Asian Longhorned Beetle 82

Management Structures and Methods Used to Control and Eradicate 

the Asian Longhorned Beetle 83

Status of Asian Longhorned Beetle Infestation 87

Funding for Asian Longhorned Beetle Eradication Efforts 88

Appendix IV: Review of Efforts to Control and Eradicate the Emerald Ash 

Borer 90

Origin and Potential Impacts of Emerald Ash Borer Infestations 90
Contents

Page ii GAO-06-353 Invasive Forest Pests

Federal, State, and Local Roles in Controlling and Eradicating the 

Emerald Ash Borer 91

Management Structures and Methods Used to Control and Eradicate 

the Emerald Ash Borer 92

Status of Infestation 99

Funding for Emerald Ash Borer Control and Eradication

Efforts 100

Appendix V: Review of Efforts to Control and Eradicate

P. ramorum 102

Origin and Potential Impacts of P. ramorum 102

Federal, State, and Local Roles in Efforts to Control and Eradicate

P. ramorum 104

Status of the P. ramorum Infestation 108

Funding of Efforts to Control and Eradicate P. ramorum 108

Appendix VI: Risk Analysis as a Tool to Address Invasive Forest Pests 110

Pest Risk Assessment Is an Essential Element of Risk Analysis 111

Risk Assessment Is a Tool for Risk Management 113

APHIS Has Conducted Risk Assessments for P. ramorum and the 

Asian Longhorned Beetle 114

Appendix VII: Comments from the Department of Agriculture 116

Appendix VIII: GAO Contact and Staff Acknowledgments 118

Tables Table 1: Number of Stakeholders Who Were Administered the GAO 

Structured Interview, by Pest and Affiliation 74

Table 2: APHIS Budget Authority for the Asian Longhorned Beetle 

for Fiscal Years 1997 through 2006 89

Table 3: APHIS Budget Authority for the Emerald Ash Borer 

Program, by Funding Source and Fiscal Year 100

Table 4: Forest Service Budget Authority for Emerald Ash Borer 

Activities, by Funding Source and Fiscal Year 101

Table 5: Summary of USDA funding for P. ramorum, Fiscal Years 

2000 Through 2005 109

Figures Figure 1: Asian Longhorned Beetle (Anoplophora

glabripennis) 11

Figure 2: Emerald Ash Borer (Agrilus planipennis Fairmaire) 12

Figure 3: Cable Spools, an Example of Solid Wood Packing 

Material That Could Harbor Pests 14

Figure 4: Areas in New Jersey and New York Quarantined for the 

Asian Longhorned Beetle 16
Contents

Page iii GAO-06-353 Invasive Forest Pests

Figure 5: Areas in Metropolitan Chicago, Illinois, Quarantined for 

the Asian Longhorned Beetle 17

Figure 6: Areas with Emerald Ash Borer Infestations in Indiana; 

Michigan; Ohio; and Ontario, Canada, as of January 

2006 20

Figure 7: Approximate Range of North American Ash Tree 

Species 22

Figure 8: Map of Area Infested with P. ramorum in California and 

Oregon, as of December 12, 2005 24

Figure 9: Forest Service P. ramorum Risk Map 26

Figure 10: “Bleeding” on Tree Trunk Caused by P. ramorum 30

Figure 11: Citrus Longhorned Beetle (Anoplophora chinensis) 34

Figure 12: APHIS Funding for the Asian Longhorned Beetle 

Program, by Source, for Fiscal Years 1997-2006 45

Figure 13: APHIS Funding for the Emerald Ash Borer Program, by 

Source, for Fiscal Years 2002-2006 46

Figure 14: APHIS Funding for the P. ramorum Program, by Source, 

for Fiscal Years 2001-2006 47

Figure 15: Number of Asian Longhorned Beetle-Infested Trees 

Identified in New York, Illinois, and New Jersey 87
Contents

Page iv GAO-06-353 Invasive Forest Pests

Abbreviations

APHIS Animal and Plant Health Inspection Service

CCC Commodity Credit Corporation

CPHST Center for Plant Health Science and Technology

DHS Department of Homeland Security

FACA Federal Advisory Committee Act

IPPC International Plant Protection Convention

ISPM International Standards for Phytosanitary Measures

OMB Office of Management and Budget

PPD Policy and Program Development

PPQ Plant Protection and Quarantine

SPS Sanitary and Phytosanitary 

USDA U.S. Department of Agriculture

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Page 1 GAO-06-353 Invasive Forest Pests

United States Government Accountability Office

Washington, D.C. 20548

A

April 21, 2006 Letr

The Honorable Richard Pombo

Chairman, Committee on Resources

House of Representatives

Dear Mr. Chairman:

Hundreds of nonnative, invasive insect and pathogen species have infested 

our nation’s forests, causing damage to our environment and costing our 

economy billions of dollars in lost revenue and cleanup. For example, 

starting in the early 1800s, American chestnut trees were devastated by a 

succession of two nonnative pathogens—ink disease and chestnut blight. 

These trees were a major component of the nation’s deciduous forests, 

were valuable to wildlife, and had wide use as a source of lumber. Today, 

chestnut trees still survive in much of their former range, but only as 

sprouts from the old root systems; unfortunately, these sprouts are struck 

down by the blight before they reach maturity. Gypsy moth is another 

serious invasive forest species that is still harming our nation’s forests 

more than 130 years after its accidental release by an amateur entomologist 

studying silkworms. The caterpillar of the moth defoliates oak, birch, 

poplar, and other important tree species, sometimes leading to the death of 

the tree. Forest pests such as these are not limited to damaging trees in 

wildland forests but may also devastate trees in suburban and urban 

neighborhoods. When forest pests kill trees, they reduce the value of 

timberlands and residential property, harm businesses, increase the risk of 

wildfire, degrade ecosystems, and place upon homeowners and local 

governments the costly burden of removing dead trees before they become 

a safety hazard. While the pests previously described have been in the 

United States for over 100 years, they continue to have an impact on the 

environment and economy.

The U.S. Department of Agriculture (USDA) has federal responsibility for 

protecting agricultural commodities and the health of the nation’s public 

and private forests and grasslands and private forests from harmful pests 

and diseases. Within USDA, the Animal and Plant Health Inspection Service 

(APHIS) and the Forest Service have primary responsibility for managing 

forest pests. In doing so, these agencies often work with other federal, 

state, and local agencies to manage and eradicate invasive species 

infestations. The Secretary of Agriculture may also draw upon the 

expertise of people outside of the federal government when developing a
Page 2 GAO-06-353 Invasive Forest Pests

response plan for invasive species.1 Funding for pest management activities 

comes through annual appropriations and the Commodity Credit 

Corporation (CCC), which is a government-owned entity that finances farm 

commodity, conservation, and trade programs and provides funding for 

agricultural-related emergencies.2

 The Secretary may transfer funds from 

the CCC (or other available USDA appropriations) for the arrest, control, 

eradication, and prevention of the spread of a plant pest and related 

expenses.

This report evaluates the federal response to three invasive forest 

pests—the Asian longhorned beetle; the emerald ash borer; and 

Phytophthora ramorum (hereafter P. ramorum), the pathogen that causes 

Sudden Oak Death. Specifically, we reviewed (1) the status of efforts to 

eradicate these three species; (2) factors that have affected the success of 

the response programs; (3) overall forest health monitoring programs;

(4) coordination of the three pest response efforts among federal and state 

agencies and other stakeholders, and communication about the response 

efforts; and (5) USDA’s use of panels of scientific experts to aid the 

responses. We also discuss in appendix VI APHIS’s use of risk assessments 

to support decisions about forest pest programs. When we use the term 

“forest pest,” we are referring to species that negatively affect trees in 

forested and urbanized areas. When we use the term “natural 

environment,” we are referring to places other than a plant nursery 

operation that have trees and plants vulnerable to a particular invasive 

species. These places could include forested and urbanized areas.

To address these objectives, we conducted in-depth reviews of these three 

forest pests. These species were chosen because of their relatively recent 

discovery in the United States; their potential threat to the nation’s forests; 

and the existence of a federally funded research, control, and management 

program for each species, and because they comprise a significant portion 

of USDA’s efforts to address specific forest pests. To analyze the efforts to 

address each pest, we visited three of the areas currently infested by the 

1

When obtaining advice from a committee or similar group comprising, in part, nonfederal 

officials, it is possible that the committee may meet the Federal Advisory Committee Act’s 

(FACA) definition of a federal advisory committee and be subject to FACA’s requirements. 

For example, the act requires that advisory committees be fairly balanced in terms of points 

of view and the functions to be performed by the committee, and the act generally requires 

that committee meetings be open to the public.

2

The corporation has the authority to borrow up to $30 billion. The borrowed funds are 

repaid through periodic congressional appropriations.
Page 3 GAO-06-353 Invasive Forest Pests

species and observed program activities, such as detection, control, and 

inspections of regulated materials, and visited with regulated industries. To 

obtain opinions from key stakeholders, we also conducted structured 

interviews with 37 USDA, state, local, and nongovernmental officials. More 

specifically, we administered the interview to 9 Asian longhorned beetle 

stakeholders, 12 emerald ash borer stakeholders, and 16 P. ramorum

stakeholders. The government officials included federal, state, and local 

officials directly engaged in one of the pest management efforts. 

Nongovernmental officials included academic scientists with expertise in 

one of the pests and representatives from the nursery industry affected by 

one of the pests and by quarantine regulations. A more detailed description 

of our scope and methodology and questions from the structured interview 

guide are presented in appendixes I and II. We performed our work 

between May 2005 and February 2006 in accordance with generally 

accepted government auditing standards.

Results in Brief Evidence suggests that efforts to eradicate the Asian longhorned beetle 

appear likely to succeed, while the emerald ash borer and P. ramorum are 

likely to continue to infest and damage forest ecosystems indefinitely 

despite efforts to control them. The Asian longhorned beetle is a 

wood-boring insect from Asia that has caused separate infestations in parts 

of New York, New Jersey, and Illinois. Over 8,000 trees infested with the 

beetle have been removed, and over 600,000 trees have been chemically 

treated to protect against the beetle. As a result of these and other actions, 

federal and state agencies have been able to reduce the size of the infested 

areas. Program managers currently believe they could eradicate the beetle 

and end their program by 2014 if 2005 funding levels are maintained; 

however, fiscal year 2006 funding has dropped significantly below the 2005 

level. The emerald ash borer is also a wood-boring insect from Asia that has 

infested large areas in Michigan; Ohio; Indiana; and Ontario, Canada, killing 

an estimated 15 million trees. The pathogen P. ramorum is the causal agent 

of the disease known as Sudden Oak Death. It is of unknown origin and has 

infested large areas in central and northern coastal California and a small 

area in southern Oregon. Although federal and state agencies have taken 

steps to reduce the spread of these two species—including attempting to 

stop the spread caused by people inadvertently moving infested 

material—the infestations are growing and few managers with whom we 

spoke believed that these species can be removed from the natural 

environment because of the size of the areas that are already infested. 
Page 4 GAO-06-353 Invasive Forest Pests

Several factors have affected the success of the federal responses to these 

three forest pest species. Specifically: 

• The biology of each of the three forest pests greatly influences the 

potential successfulness of eradication efforts. The Asian longhorned 

beetle is a large, conspicuous bug that does not fly far from the core 

infestation. As a result, it is fairly noticeable and does not spread 

quickly. Conversely, the emerald ash borer and, in particular

P. ramorum are more insidious and can spread over greater distances 

and more rapidly.

• Delays in detection and identification allowed the three pests we 

reviewed to become established and spread before control efforts 

began. In each instance, several years elapsed between the arrival of the 

pest and its discovery, thereby giving the pest time to become firmly 

established in the environment. 

• Quarantines have been helpful in containing human-induced spread of 

these forest pests. Federal and state agencies have placed restrictions 

on the movement of potentially infested materials, such as nursery 

plants and firewood. They also have mounted large public education 

campaigns to inform the public about the need to refrain from activities 

that could spread the pests. While program managers with whom we 

spoke believed that the quarantines have limited the spread of each pest, 

managers of the emerald ash borer and P. ramorum programs also 

noted that the quarantines were difficult to establish and enforce, and 

that they have not completely stopped the movement of those pests. 

• Efforts to address the three forest pests are limited by the lack of 

cost-effective technologies for eradicating them. To date, the only 

method available to eradicate these pests in infested areas is to destroy 

the trees and plants that have been infested. Agencies have destroyed 

thousands of trees infested with the Asian longhorned beetle in New 

York, Illinois, and New Jersey and hundreds of thousands infested with 

the emerald ash borer in Michigan, Ohio, and Indiana. In the case of the 

ash borer, many more infested trees remain to be removed. On the West 

Coast, few trees infested with P. ramorum have been removed relative 

to the number infested because the pathogen is so widespread, but over 

1 million nursery plants have been destroyed. Chemical treatments that 

can eradicate infestations of the three pests on a broad scale are not 

available, although they can be helpful in preventing the pests’ spread. 

Such treatments have been used extensively for the Asian longhorned 
Page 5 GAO-06-353 Invasive Forest Pests

beetle; however, they are impractical in the cases of the emerald ash 

borer and P. ramorum because of the size of the infestations. Research 

on alternative control technologies is ongoing for all three pests. 

• While USDA has budgeted over $420 million on control programs for 

these pests, program managers told us that funding has not been 

sufficient to fully implement their programs. For example, according to 

managers of the Asian longhorned beetle program, reduced funding in 

fiscal years 2002, 2003, and 2006 delayed the estimated date of 

eradication from 2009 to as late as 2020 and increased the risk that the 

pest could spread to new locations during this time. In the case of the 

emerald ash borer, funding in fiscal year 2005 was about one-half of 

what the management team estimated was needed, while funding for 

fiscal year 2006 is less than one-third of the estimated need. As a result, 

state agencies have not been able to fully implement a tree removal plan 

recommended by the scientific advisory panel to contain the pest. 

USDA has monitored the health of the nation’s public and private forests 

for decades. Some programs are focused on broad issues, such as tree 

species composition and general health conditions, while others are 

focused on identifying specific problems. However, for the three forest 

pests we reviewed, as well as others, delays in detection and identification 

that allowed the pests to become established and spread before control 

efforts began illustrate that forest health monitoring has not been adequate. 

This is particularly the situation in urban areas that are common 

destination points for internationally traded cargo—a frequent pathway for 

pests. For example, the Asian longhorned beetle is thought to have begun 

infesting trees in New York City in the mid-1980s. It had been intercepted at 

warehouses around the country and was known to be a problem in its 

native range. However, there was no specific effort to determine whether it 

had made its way into the natural environment. It was not detected in the 

natural environment until 1996, when a New York City homeowner noticed 

suspicious holes in one of his trees. While a citizen report is an important 

component of an early warning system, a thorough government monitoring 

program—triggered by the detection of the beetle at U.S. ports—might 

have detected it sooner. The Forest Service and APHIS have taken steps in 

recent years to increase monitoring and otherwise improve their early 

warning system for forest pests, but these agencies could expand forest 

health monitoring in urban areas to further reduce the risk that new 

introductions will escape detection and result in substantial natural 

resource damage. Agency officials have estimated the cost of expanding 

existing programs to improve urban forest health monitoring to be about
Page 6 GAO-06-353 Invasive Forest Pests

$3 to 4 million per year, and they believe that doing so could help avoid 

more costly pest impacts and management costs. We are recommending 

that the Secretary of Agriculture expand current efforts to monitor forest 

health conditions, particularly in urban areas that are at high risk of 

receiving invasive insects and diseases.

For the three infestation response programs we reviewed, we found that 

coordination between federal and state agencies was initially lacking, and 

that USDA had not adequately kept management plans up to date to 

communicate with the public program accomplishments, strategies, and 

long-term funding needs, despite major changes in the programs. For each 

pest program we reviewed, a majority of the 37 stakeholders with whom 

we spoke told us that appropriate federal and state mechanisms are now in 

place to coordinate the work of multiple agencies and levels of government 

but highlighted weaknesses that had occurred and made suggestions for 

improvements. A common stakeholder complaint was that agriculture and 

natural resource agencies at either the federal or state level did not always 

work well together at the beginning of the response effort, thereby delaying 

management progress. Such problems could be averted in new pest 

response efforts if attention is paid to the lessons learned from the three 

pest management efforts we reviewed. Regarding communications about 

the response efforts, general principles of transparency and accountability, 

as well as the National Invasive Species Council’s guidelines for rapid 

response programs, stress the importance of informing the public about the 

status of management programs, planned strategies, and funding needs. 

Along these lines, Congress passed a law in 2004 requiring that USDA, 

subject to the availability of appropriated funds, prepare a national plan for 

the control and management of Sudden Oak Death, which is caused by

P. ramorum. The national plan is to include certain information. However, 

the agency published a plan in 2005 that did not include required cost 

estimates. Similarly, while the Asian longhorned beetle and emerald ash 

borer programs have publicly available management plans, the plans do not 

reflect the significant impacts that funding reductions have had on the 

prospects for controlling the infestations. We are recommending that the 

Secretary of Agriculture prepare, publish, and regularly update 

management plans for pests for which USDA has initiated a management 

program.

USDA has convened panels comprising federal and nonfederal scientific 

experts to assist the agency in responding to each of the three pests we 

reviewed. While program managers believe that these panels have been 

useful, we and some stakeholders have concerns about how they were 
Page 7 GAO-06-353 Invasive Forest Pests

formed and are being operated. For example, some stakeholders believed 

that USDA should have convened specific panels more frequently and 

made the panel process more open and transparent to interested parties. 

We found that USDA does not have written procedures for how science 

advisory panels are to be formed and operated and when such panels 

should be chartered as federal advisory committees under the Federal 

Advisory Committee Act (FACA). There are certain principles in FACA that, 

if included in operational procedures for pest advisory panels, could 

address or minimize some of the concerns raised about their use. We are 

recommending that the Secretary of Agriculture implement written 

procedures that broadly define when and how to operate panels of 

scientific experts for the purpose of assisting pest management teams, 

including a discussion on how to determine when such panels should be 

chartered as advisory committees under FACA.

USDA provided comments on a draft of this report and said that it was 

comprehensive and well written. However, USDA stated that it believed the 

report contained an overly critical tone regarding its response to the three 

infestations and expressed the view that the coalition of federal and 

nonfederal entities had done a reasonable job. We believe the report fairly 

captures the agency’s performance recognizing the daunting challenges 

that USDA and its collaborators have faced in responding to the 

infestations, while also accurately portraying the comments and opinions 

of the government officials we interviewed. Unfortunately, despite 

considerable effort, the fact remains that two of the three pests are 

spreading and are not likely to be eradicated. Our intention is to draw 

lessons from these pest infestations that can be used to reduce the effects 

of future infestations. 

USDA also wrote that while it did not have major concerns about our 

recommendations, it did not completely agree with them. With regard to 

our recommendation that USDA expand forest health monitoring, the 

department suggested that we also examine the role that nonfederal 

entities play, their responsibilities, and the outcomes of their efforts. We 

recognize that nonfederal entities make important contributions to forest 

health monitoring; in fact, the USDA monitoring programs we discuss in 

this report are collaborative programs with nonfederal entities, including 

state forestry and agriculture agencies and private landowners. As the lead 

federal agency, USDA has an important leadership role to play with these 

nonfederal agencies. We believe that adopting our recommendations would 

enhance USDA’s leadership position and help lead all responsible parties to 

more effective results. USDA commented that it supported our second 
Page 8 GAO-06-353 Invasive Forest Pests

recommendation to keep management plans up to date, but the agency also 

stated its belief that it had done a reasonable job on the plans for the three 

pests we reviewed, given competing demands for time and resources. 

USDA characterized our third recommendation as calling for putting “more 

rigor into how science panels are formed” and said that “seemed 

reasonable.” It appears, however, that the agency interpreted our 

recommendation to imply that science panels should always be chartered 

under FACA. The agency stated that chartering panels under FACA would 

hamper their ability to address invasive species issues. We recognize that 

the FACA process requires that certain steps be taken that could slow the 

establishment of a science panel at a time when one is quickly needed. 

However, our recommendation does not state that science panels always 

be chartered under FACA, but rather that USDA develop written 

procedures that clarify when a science panel needs to be chartered under 

FACA. The letter from USDA is reprinted in appendix VII.

Background Invasive species pose significant risks for the United States and can cause 

serious economic and environmental damage. The U.S. Department of 

Agriculture (USDA) is the lead federal agency for protecting the nation’s 

agriculture and public and private forests from harmful pests and diseases. 

USDA often collaborates with other federal, state, and local agencies in 

carrying out these duties. Three recent infestations—the Asian longhorned 

beetle; the emerald ash borer; and Phytophthora ramorum (hereafter

P. ramorum), the pathogen that causes Sudden Oak Death—offer valuable 

illustrations of how the federal government manages the threats posed by 

invasive species.

Potential Economic and 

Environmental Impacts of 

Invasive Species

As we have previously reported, the impact of invasive species in the 

United States is widespread, and their consequences for the economy and 

the environment are profound.3

 They affect people’s livelihoods and pose a 

significant risk to industries such as agriculture, ranching, and fisheries. 

The cost to control invasive species and the cost of damages they inflict, or 

could inflict, on property or natural resources are estimated to total billions 

of dollars annually. Among the broad universe of invasive species are 

3

GAO, Invasive Species: Cooperation and Coordination Are Important for Effective 

Management of Invasive Weeds, GAO-05-185 (Washington, D.C.: Feb. 25, 2005); and

Invasive Species: Clearer Focus and Greater Commitment Needed to Effectively Manage 

the Problem, GAO-03-1 (Washington, D.C.: Oct. 22, 2002).
Page 9 GAO-06-353 Invasive Forest Pests

insects and pathogens that can harm trees, including trees that are 

important to industry, homeowners and communities, wildlife, and the 

environment. 

Federal and State 

Responsibilities

In 1999, President Clinton signed Executive Order 13112 creating the 

National Invasive Species Council, which now comprises the heads of 13 

departments and agencies, in part to coordinate federal efforts on invasive 

species. In 2001, the council issued a national management plan that 

contains numerous recommendations for managing invasive species, 

including several on improving early detection and rapid response to 

infestations. For example, in response to the management plan, the council 

issued in 2003 general guidelines for establishing and evaluating invasive 

species early detection and rapid response systems.

Within USDA, the Animal and Plant Health Inspection Service (APHIS) is 

the lead agency for responding to forest pests and diseases that might harm 

U.S. agriculture. The Department of Homeland Security (DHS) also plays a 

critical role in protecting agricultural interests by inspecting ships, 

airplanes, vehicles, cargo, and passengers and their baggage for prohibited 

agricultural materials that may serve as carriers for pests and disease. 

USDA conducted some of these inspections in the past, but the Homeland 

Security Act of 2002 transferred this function, among others, to DHS.4

 This 

report does not address DHS pest inspection programs. However, we plan 

to issue a separate GAO report on inspection programs later this spring.5

This report focuses on USDA programs to address forest pests that have 

arrived in the United States despite preventive efforts. APHIS manages 

pests that have arrived by conducting detection surveys; issuing 

quarantines; directing eradication efforts, such as removing infested trees 

or applying pesticides; developing control technologies; and performing 

public outreach. The Forest Service—whose mission of forest protection 

extends to all public and private forest land—undertakes reforestation of 

areas affected by pests and plays an important role in surveys, research, 

and management. Other federal agencies may also be involved in some 

aspects of invasive species management, including managing federal lands 

4

Pub. L. No. 107-296, 116 Stat. 2135 (2002).

5

The report will be available on GAO’s Web site, identified as GAO-06-644. 
Page 10 GAO-06-353 Invasive Forest Pests

that may be impacted by invasive species and administering programs to 

address them. 

State agencies also play an important role in managing invasive species. 

For example, state agencies impose quarantines to prevent the movement 

of infested materials within their state and take actions to eradicate pests. 

APHIS and the Forest Service enter into cooperative agreements with 

states to jointly carry out eradication programs and provide funding 

assistance for these programs. APHIS and the states also monitor for 

specific plant pests, including some that have already arrived in the country 

and others that have not. 

The Asian Longhorned 

Beetle 

The Asian longhorned beetle was initially detected in the United States in 

Brooklyn, New York, in August 1996, and is suspected to have entered the 

country years before in solid wood packing material from Asia, where it is a 

pest of hardwood trees. Subsequent infestations were discovered in 

Chicago, Illinois, in July 1998, and in New Jersey in October 2002. The 

beetle was also discovered in Toronto, Canada, in September 2003. The 

beetle infestations have been limited to urban forests in New York; Illinois; 

New Jersey; and Ontario, Canada. 

While the natural spread of the Asian longhorned beetle has been very slow 

to nonexistent, the beetle represents a serious threat to forests and urban 

trees. The potential impact to forests is the loss of 71 billion trees valued at 

over $2 trillion dollars. In addition, urban areas could lose as much as 35 

percent of their tree canopy cover and 30 percent of their trees (1.2 billion 

trees), with an estimated loss of value of $669 billion.6

 Other potential 

adverse impacts could affect the forest products industry (lumber and 

furniture), maple syrup production, and fall foliage tourism, as well as 

decrease property values, cause aesthetic damage, and lessen the 

environmental benefits of trees. The potential also exists for the beetle to 

seriously alter the ecological diversity of the natural forests in North 

America, with additional impacts on wetlands. Figure 1 shows the beetle, 

and appendix III contains more detail on its infestation and the 

management program. 

6

David J. Nowak, Judith E. Pasek, Ronaldo A. Sequeira, Daniel E. Crane, and Victor C. 

Mastro. “Potential Effect of Anoplophora glabripennis (Coleoptera: Cerambycidae) on 

Urban Trees in the United States.” Journal of Economic Entomology, vol. 94, no. 1 (2001).
Page 11 GAO-06-353 Invasive Forest Pests

Figure 1: Asian Longhorned Beetle (Anoplophora glabripennis) 

The Emerald Ash Borer The emerald ash borer was initially detected in the United States in 2002 in 

southeastern Michigan, but the insect is estimated to have arrived in the 

country in the early 1990s, in solid wood packing material. Emerald ash 

borer infestations cover roughly 40,000 square miles in Indiana; Michigan; 

Ohio; and Ontario, Canada, and the natural spread of the species continues. 

Surveys also regularly find new areas in the three states infested with 

beetles that inadvertently were moved by people.

The emerald ash borer can kill all 16 species of North American ash trees 

and, as of November 2005, the pest had killed an estimated 15 million trees. 

The potential economic impacts of the infestation are significant because 

ash trees represent billions of dollars in ornamental, industrial, and 

environmental value. Figure 2 shows the ash borer, and appendix IV 

contains more detail on its infestation and the management program.

Source: Donald Duerr, USDA Forest Service, www.forestryimages.org.
Page 12 GAO-06-353 Invasive Forest Pests

Figure 2: Emerald Ash Borer (Agrilus planipennis Fairmaire)

P. ramorum P. ramorum (the pathogen that causes Sudden Oak Death) was initially 

detected in the United States in 2000. While it is believed to have appeared 

in the country as early as the mid-1990s, how it arrived here is unknown. 

Currently, P. ramorum infects natural areas in 14 counties of California and 

part of Curry County, Oregon. The pathogen has also been inadvertently 

shipped to, and in most cases eradicated from, nurseries in 22 states. The 

natural and artificial spread of P. ramorum continues. However, improved 

detection of the pathogen in nurseries has led to a decrease in the number 

of detected interstate shipments of infected plants. For example, in 2005, 

99 confirmed positive detections of P. ramorum were associated with 

nursery plants in 7 states, down from 176 positives in 22 states in 2004. 

P. ramorum affects oak trees and other host and associated host plants in 

natural areas and nurseries. P. ramorum can kill valuable oak trees in 

urban and natural environments and can infect and devalue, but not 

necessarily kill, ornamental plants such as rhododendron. Currently,

Source: David Cappaert, www.forestryimages.org.
Page 13 GAO-06-353 Invasive Forest Pests

P. ramorum is known to infect species in more than 50 plant genera.7

These plants are worth billions of dollars in ornamental, timber, wildlife, 

and environmental value. The pathogen has killed tens of thousands of 

trees and led to the destruction of hundreds of thousands of nursery plants. 

Appendix V contains more detail on the P. ramorum infestation and 

management program.

The Asian longhorned beetle, the emerald ash borer, and other invasive 

species arrived in the United States in solid wood packing material 

accompanying cargo from overseas. This review did not address 

government regulations or practices aimed at preventing this from 

occurring. Following is a brief description of actions USDA has taken to 

reduce the risks posed by solid wood packing material. 

7

The term “genera,” the plural form of genus, refers to a category of biological classification 

ranking between the family and the species, comprising related species.
Page 14 GAO-06-353 Invasive Forest Pests

Figure 3: Cable Spools, an Example of Solid Wood Packing Material That Could 

Harbor Pests

Source: Nick Humphreys, Natural Resources Canada.

Recent USDA Regulations for Solid Wood Packing Material Are Intended to Reduce Pest Introductions, but Some Have 

Questioned Their Future Effectiveness

A major pathway through which forest pests enter this country is solid wood packing material. This material includes pallets, crates, 

boxes, cable spools, and pieces of wood used to support or brace cargo. The Asian longhorned beetle and the emerald ash borer—as 

well as many other pests—are thought to have arrived in this country hidden in this type of material. We did not review the federal 

government’s efforts to prevent the introduction of pests. However, one major development in this area bears noting. In December 1998, 

an APHIS interim rule took effect requiring that solid wood packing material arriving in the United States from China be treated to 

reduce the likelihood that it harbored live pests. In September 2004, APHIS published a final rule that adopted an international standard 

for treating solid wood packing material. The new standard requires that wood packing material from all places be treated either with 

heat or a fumigant known as methyl bromide. APHIS will phase in enforcement of the rule, with full enforcement by July 2006. According 

to APHIS, there has been a decrease in pests associated with solid wood packing material from China since APHIS began requiring

that the material be treated prior to importation. The agency believes that the new and broader regulations will further reduce the 

introduction of new species. If the standard does add protections, the need for early detection and rapid response may decrease. 

Although, as a Forest Service entomologist noted to us, detection is still needed for pests that have arrived in recent years. 

However, solid wood packing material is not the only pathway by which new pests are introduced, and some interested parties 

commented during the rulemaking process that the new regulations are not protective enough to kill all pests. Comments included

concerns that the heat treatment and fumigation standards are not adequate, and that it will be too difficult to ensure that those 

treatments were conducted. (Methyl bromide is also controversial because it contributes to stratospheric ozone depletion.) Others 

commented that a more protective approach would be to phase out the use of solid wood packing materials and replace them with other 

materials, such as manufactured wood or plastic. In September 2005, California, Connecticut, Illinois, and New York sued USDA, 

claiming that the new regulations are not adequately protective and seeking a court order directing the agency to examine more 

effective and less environmentally harmful methods of preventing destructive insects from entering the country.
Page 15 GAO-06-353 Invasive Forest Pests

Eradicating the Asian 

Longhorned Beetle 

Appears Likely, While 

Success on the 

Emerald Ash Borer and 

P. ramorum Is Less 

Promising

Evidence suggests that the Asian longhorned beetle will be eradicated, 

while the emerald ash borer and P. ramorum are likely to continue to infest 

and damage forest ecosystems indefinitely, despite efforts to control them. 

When first discovered, the areas infested with the Asian longhorned beetle 

were tens of square miles. Although the known boundaries of the infested 

areas expanded as surveys were conducted, government efforts in Illinois, 

New Jersey, and New York have been able to reverse the trend and reduce 

the size of the infested areas. Program managers with whom we spoke 

believed they could eradicate the beetle and end their program by 2014 if 

funding remained at 2005 levels. However, recent funding reductions raise 

doubts about achieving their goal by that date. In contrast, the areas 

infested with the emerald ash borer and P. ramorum were already many 

hundreds, if not thousands, of square miles in size by the time the pests 

were identified. While government agencies have taken steps to reduce the 

human-induced spread of these two species, the infestations are still 

growing, and few officials we spoke with believed that the pests can be 

removed from the natural environment. 

Program Officials Believed 

That the Asian Longhorned 

Beetle Will Be Eradicated

Eight of the nine stakeholders we interviewed regarding the Asian 

longhorned beetle believed that it will be eradicated from Illinois, New 

Jersey, and New York.8

 APHIS’s current goals for Illinois and New Jersey 

are to confirm eradication and end the management programs in 2008 and 

2011, respectively. The current goal for completing the program in New 

York is 2014, although that estimate is dependent upon consistent and 

adequate funding. 

The stakeholders’ opinions on the likelihood of eradication are based on a 

number of factors, including the relatively small areas of infestation and 

the success to date in eradicating the beetle in nearly all of the Illinois 

locations and one of two locations in New Jersey. At their peak, 

quarantines covered 183 square miles in the three states (see figs. 4 and 5). 

8

One stakeholder, a member of academia, did not believe eradication is possible under the 

current management program.
Page 16 GAO-06-353 Invasive Forest Pests

Figure 4: Areas in New Jersey and New York Quarantined for the Asian Longhorned Beetle

First Central Long Island ALB detection

Date: 9/96

First Islip ALB detection

Date: 9/99

New Jersey

Carteret

Manhattan

Central Long Island

Islip (Long Island)

Queens

Asian longhorned beetle (ALB) quarantine boundaries

Sites infested with the Asian longhorned beetle

Sources: USDA, APHIS, and GAO.

First Carteret detection

Date: 8/04

First Jersey City detection

Date: 10/02 

Brooklyn

First New York State ALB detection

Date: 8/96
Page 17 GAO-06-353 Invasive Forest Pests

Figure 5: Areas in Metropolitan Chicago, Illinois, Quarantined for the Asian 

Longhorned Beetle

After 2 years of surveys in these locations have shown no evidence of the 

beetle, program officials can begin removing the quarantines, and they have 

done so in some areas. According to agency guidelines, after 4 years of 

negative surveys, program officials can declare that the beetle has been 

eradicated from these areas. 

Lake

Michigan

Addison

Summit

Kilbourn Park

Oz Park

Ravenswood

Park Ridge

O‘Hare

Airport

Chicago

Illinois

Asian longhorned beetle quarantine boundaries

Sites infested with the Asian longhorned beetle

Sources: APHIS and GAO.
Page 18 GAO-06-353 Invasive Forest Pests

Prior to the implementation of regulatory controls, the Asian longhorned 

beetle was spread artificially through the movement of wood products, 

such as firewood and wood debris. Program managers are confident that 

quarantines and other regulatory actions have stopped the artificial spread 

of the beetle. The natural spread of the Asian longhorned beetle has been 

very slow because it does not travel far from its original nesting site, unless 

forced to do so by a lack of food. In addition, adult beetles and the exit 

holes they create when they emerge from trees are relatively easy to see, 

and the public, having been educated about the beetle, has helped find new 

infestations.

The damage to trees caused by the Asian longhorned beetle has been 

relatively minor in comparison to the threat USDA estimated it could pose 

and in comparison to the damage caused by the emerald ash borer and 

P. ramorum. The beetle attacks hardwood tree species that grow primarily 

in the eastern United States, including many that are valued in both urban 

and forested areas.9

 While it appears that the beetle will be eradicated, 

according to USDA, if left unchecked the pest has the potential to do more 

damage to a wider range of hardwood tree species in North American 

forests than the Dutch elm disease, chestnut blight, and gypsy moth 

combined. Presently, the known beetle infestations have been confined to 

trees in large urban areas. For urban areas, USDA estimates that property 

owners and municipalities could lose 35 percent of their tree canopy cover 

and incur 30 percent tree mortality (1.2 billion trees), damage valued at 

$669 million.10 Losses that are difficult to quantify include property value 

depreciation and the loss of the aesthetic and environmental benefits to 

property owners. If the beetle were to escape its current urban 

environment and establish itself in natural forests, USDA estimates that 

about 30 percent, or 71 billion trees on timberland, valued at over $2 trillion 

could be lost.11 (These are worst-case scenarios, and we present them to 

indicate the potential magnitude of the problem.) The $2 trillion does not 

9

The various trees that serve as hosts for the Asian longhorned beetle include the following: 

very good hosts are maple, boxelder, horsechestnut, buckeye, willow, and elm trees; good 

hosts are birch and London plane trees; and occasional hosts are mimosa, hackberry, ash, 

poplar, and mountain ash trees. 

10David J. Nowak, Judith E. Pasek, Ronaldo A. Sequeira, Daniel E. Crane, and Victor C. 

Mastro. “Potential Effect of Anoplophora glabripennis (Coleoptera: Cerambycidae) on 

Urban Trees in the United States.” Journal of Economic Entomology, vol. 94, no. 1 (2001).

11The Forest Service Web address for this information is 

http://www.fs.fed.us/ne/syracuse/Data/Nation/data_list_alb.htm.
Page 19 GAO-06-353 Invasive Forest Pests

include the adverse impact to such industries as forest products, maple 

syrup, and fall foliage tourism in the Northeast. Additionally, the spread of 

the Asian longhorned beetle could alter the ecological diversity of the 

natural forests in North America and significantly alter the tree makeup of 

wetlands.

Other factors contributing to stakeholders’ optimism about eradication of 

the Asian longhorned beetle include the existence of a focused and 

cooperative management team in each location and an effective mix of 

control measures, including good cooperative working relationships and an 

aggressive public outreach and education program. 

Eradicating the Emerald 

Ash Borer Does Not Appear 

Likely

None of the 12 stakeholders we interviewed believed that the emerald ash 

borer could be eradicated in the United States, given our current 

knowledge and level of effort. The areas infested with the emerald ash 

borer have exceeded 40,000 square miles in Michigan; Indiana; Ohio; and 

Ontario, Canada, and continue to grow (see fig. 6). The pest has spread by 

both natural and artificial means. Research has shown that ash borers, 

particularly mated females, are capable of flying several miles. Government 

studies have used the estimate that ash borer populations can spread 5 to 

10 miles per year as they grow in number and search for new host trees. 

More dramatically, the artificial movement of the pest in infested logs, 

firewood, or nursery trees can start new infestations hundreds of miles 

away. 
Page 20 GAO-06-353 Invasive Forest Pests

Figure 6: Areas with Emerald Ash Borer Infestations in Indiana; Michigan; Ohio; and 

Ontario, Canada, as of January 2006

Sites under evaluation

(symptoms, found in

firewood, or eradicated)

Sites infested with

the emerald ash

borer

Emerald ash borer

quarantine

boundaries

National Forests

Michigan

Ontario

Ohio Indiana

Sources: APHIS and GAO.
Page 21 GAO-06-353 Invasive Forest Pests

According to the Michigan Department of Agriculture, the ash borer has 

killed an estimated 15 million trees and has caused “staggering costs for 

tree removal, disposal, and replanting [that] have overwhelmed local units 

of government.” There are16 species of ash trees in North America, and all 

are believed to be vulnerable to the ash borer (see fig. 7 for the geographic 

range of ash species).12 Several stakeholders with whom we spoke were 

concerned that all ash species in U.S. forest were at risk. USDA also 

estimated that the cost of removing and replacing dead ash trees in urban 

and suburban areas could reach $7 billion over a 25-year period.13

12USDA estimates that there are approximately 8 billion ash trees in U.S. forests.

13USDA is in the process of refining this estimate.
Page 22 GAO-06-353 Invasive Forest Pests

Figure 7: Approximate Range of North American Ash Tree Species

Sources: USDA Forest Service and MapArt.

Approximate range of ash tree species in North America
Page 23 GAO-06-353 Invasive Forest Pests

The current federal management approach calls for eradicating the ash 

borer in Indiana and Ohio and containing, but not eradicating, the ash borer 

in Michigan. This approach reflects the enormity of the task of trying to 

eradicate the pest in Michigan, given its widespread distribution and the 

lack of low-cost management tools. What it means, though, is that even if 

the program is able to contain the beetle within Michigan, the pest will 

continue to kill ash trees across the Michigan landscape and also continue 

to pose a threat to other states. While several stakeholders told us they 

believed that North American ash species are in danger of being eliminated 

as a component in forested areas, others suggested that it is possible to 

slow the spread of the ash borer as has been done with the European gypsy 

moth. A significant difference between those two pests, however, is that 

while the gypsy moth is a serious tree defoliator, it does not inevitably kill 

trees as the ash borer does.

Eradicating 

P. ramorum—the Pathogen 

That Causes Sudden Oak 

Death—Does Not Appear 

Likely

None of the 16 stakeholders we interviewed believed that P. ramorum

could be eradicated from California’s natural environment because of the 

current size of the infestation, its potential for spread, and the lack of 

effective management tools.14 The area currently infested by P. ramorum 

has exceeded 19,000 square miles in central California and continues to 

grow as the pathogen is spread by both natural and artificial means (see fig. 

8). 

14Fifteen of the 16 stakeholders did not believe eradication was possible; 1 stakeholder was 

uncertain.
Page 24 GAO-06-353 Invasive Forest Pests

Figure 8: Map of Area Infested with P. ramorum in California and Oregon, as of 

December 12, 2005

Counties with Phytophthora ramorum confirmed in wildland 

Host species for Phytophthora ramorum

Confirmed isolation of Phytophthora ramorum

Lake

Monterey

Santa Mateo

Santa Clara

Santa Cruz

Alameda

Humboldt

Sonoma

Marin

Solano

San Francisco

Napa

California

Oregon Curry

Sources: Karen Tuxen and Maggie Kelly, http//kellylab.berkeley.edu/SODmonitoring and GAO.

Contra Costa
Page 25 GAO-06-353 Invasive Forest Pests

One stakeholder who is familiar with forest pathogens stated that no 

invasive forest pathogen has ever been eradicated from North American 

forests. Consistent with this belief, the USDA management strategy in 

California calls for control of P. ramorum in the natural environment, 

rather than eradication.15 APHIS and state agencies are, however, striving 

to eradicate the pathogen from nursery environments to reduce the risk 

that infected ornamental plants will spread the pathogen throughout the 

country. Six stakeholders—federal, state, and nursery officials—told us 

they believed the pathogen could be eradicated from nurseries, a belief 

bolstered by evidence of the control of other Phytophthoras in nurseries. 

In the United States, the only known forest infested with P. ramorum

outside of California is a small area in Curry County, Oregon (see fig. 8). 

Oregon, with assistance from APHIS and the Forest Service, is working to 

eradicate this infestation. Five of the 16 stakeholders—federal, state, 

university, and nursery officials in Oregon—we interviewed told us that 

they believed small-scale eradication efforts such as this can succeed. 

Research has shown that the pathogen thrives in wet, moist weather, and 

spores from infected plants spread naturally in water, air, or soil. People 

and animals can also track spores into uninfected areas, and the movement 

of infected plants or soil could start new infestations across the country.

P. ramorum is known to threaten and could potentially kill numerous 

species of oak in North America and kill other trees, such as tanoak (not a 

true oak species). P. ramorum can also infect, but not necessarily kill, 

other trees, including California bay laurel, as well as ornamental plants, 

such as rhododendron and camellia. P. ramorum has already killed tens of 

thousands of tanoaks, coast live oaks, and black oaks with a mortality rate 

as high as 85 percent in some areas of California. A preliminary risk map 

created by the Forest Service, on the basis of potential pathways, 

susceptible plant species, and favorable weather conditions, shows that the 

natural areas at highest risk for P. ramorum are in the coastal areas of 

California, Oregon, and Washington and the Appalachian Mountains (see 

fig. 9). 

15In July 2001, APHIS designated P. ramorum as a domestic control program rather than an 

eradication program after determining that the infestation in California was too widespread 

to eradicate. A domestic program is one in which the agency expects to engage in 

suppression for an indefinite period of time.
Page 26 GAO-06-353 Invasive Forest Pests

Figure 9: Forest Service P. ramorum Risk Map

Many stakeholders believe that the tanoak—a valuable tree for wildlife, 

certain Indian tribes, and soil stability along steep inclines—is in danger of 

being eliminated as a component of the forest understory in California and 

Oregon because of P. ramorum. However, the same risk does not apply to 

true oak trees because they have shown greater resistance to the pathogen. 

Still, the potential threat to the commercial timber industry could exceed 

$30 billion dollars if P. ramorum were to become established in Eastern 

Low

Moderate

High

Relative risk

Sources: USDA Forest Service and GAO.
Page 27 GAO-06-353 Invasive Forest Pests

deciduous forests. California timberlands alone are valued at over $500 

million for forest products. In addition to the timber industry, the potential 

impact of the pathogen on the U.S. nursery industry is high. Since detection 

of the pathogen in a Santa Cruz nursery in 2001, damage to the nursery 

industry has been estimated to be between $3 and $17 million, not 

including lost sales. The California Association of Nurseries and Garden 

Centers estimated that California nurseries lost $25 million in sales in the 

spring of 2004 alone when other states prohibited nursery shipments from 

California. In addition, the economic impact on homeowners is potentially 

significant if trees that contribute to property value are lost to the disease. 

The cost of removing infected trees, such as large ornamental oaks, is also 

high, anywhere from $500 to $5,000 per tree. According to a Forest Service 

official, there are no government reimbursement programs to cover tree 

removal costs, except in Oregon where federal funds are used for 

eradication purposes, including tree removal on private lands in the Curry 

County quarantined area. 

Efforts to Eradicate 

These Pests Have Been 

Affected by Several 

Factors 

Several factors have affected the federal response to these three 

infestations. First, specific biological characteristics of each species affect 

the ease with which the pest is detected and its ability to move across the 

landscape. Second, in each instance, several years elapsed between the 

arrival of the pest and its discovery, thereby giving the pest time to become 

firmly established in the environment. Third, quarantines have helped to 

slow the spread of the pests, but they are difficult to implement and 

enforce. Fourth, in all three situations, program managers have noted that 

they lack cost-effective technologies for controlling the pests. Finally, 

insufficient funding has (1) restricted program managers’ ability to use the 

tools they do have to minimize the spread of the pests and (2) raised 

concerns among managers about being able to achieve future goals. 

Biological Characteristics of 

Each Species Greatly Affect 

the Success of Control 

Efforts 

The three invasive forest pests we reviewed are quite different organisms, 

and those differences have affected the success of management programs. 

The most basic characteristic is that two of these pests are insects while 

the third—P. ramorum—is a pathogen. More important, however, is how 

species-specific characteristics affect the relative ease of their detection; 

their ability to reproduce and move across the landscape; and their 

vulnerability to safe, available pesticides. The Asian longhorned beetle 

exhibits fewer of the characteristics that hinder control efforts than do the 
Page 28 GAO-06-353 Invasive Forest Pests

emerald ash borer and P. ramorum; hence control of the beetle has been 

more successful.

Asian longhorned beetle The Asian longhorned beetle has some biological characteristics that make 

its detection difficult, but others that make its management generally 

feasible. The beetle is a wood-boring insect that spends most of its life 

within the inner wood of its host tree, thereby hindering their detection 

during much of the year. During these months, the beetle can be easily and 

unknowingly moved in firewood, live trees, or fallen timber, thereby 

contributing to its spread; the beetle is also less vulnerable to insecticide 

applications during this time. In addition, government researchers have not 

been able to develop a lure that will attract the beetle to a trap.

On the other hand, when adult beetles emerge from the trunks of trees, 

they are relatively conspicuous because of their size (up to 11⁄2 inches long), 

their shiny black body with white spots, and their long antennae that are 

banded with black and white stripes. After emerging, the adult beetles also 

leave behind a conspicuous, perfectly round exit hole somewhat larger 

than the diameter of a pencil. In addition, females chew a small hole into 

which they deposit their eggs. Although less conspicuous than exit holes, 

these holes—known as oviposition pits—are nevertheless useful in 

intensive detection surveys and allow for the detection and removal of 

trees before the eggs hatch and beetles emerge and spread to other areas. 

Exit holes may ooze sap and deposits of frass (i.e., insect waste and 

sawdust) that may collect on the tree trunk and limbs. In fact, it was the 

beetle’s size and coloring that piqued people’s interest and led to private 

landowners’ detection of the beetle in Illinois, New Jersey, and New York. 

According to Asian longhorned beetle management officials, public reports 

of beetle sightings soar after public service announcements that discuss the 

beetle. While many sightings reported by the public turn out to be false 

leads because the beetle is similar to some noninvasive beetles, other 

sightings have been productive. For example, shortly after hearing about 

the beetle on a radio show about gardening, a New Jersey resident called 

with a report that led to the detection of one of two infestations in the state. 

The beetle’s dispersal habit is perhaps the most important biological factor 

contributing to management success. One program official noted that the 

beetle is “lazy” and tends to remain on the tree from which it emerged, 

unless, for example, the beetle is forced to move to another host due to a 

shortage of food. In short, the beetle does not naturally spread quickly over 

large areas. When taken together, these characteristics have made it easier 

for management teams to detect, contain, and eradicate infestations. On 

the other hand, according to one state Asian longhorned beetle program 
Page 29 GAO-06-353 Invasive Forest Pests

manager, less than 1 percent of potential host trees are infested, thereby 

making detection of the beetle more difficult.

Emerald ash borer A number of biological factors contributed to the lag time between the start 

of the emerald ash borer infestation and the positive identification of the 

pest. First, the ash borer spends most of its life hidden inside trees. Female 

beetles lay tiny eggs in bark crevices, thereby making them difficult to 

detect. Visible symptoms of infestation, such as branch dieback and 

epicormic shoots, do not appear until at least 1 year after attack and could 

be attributed to other causes.16 When adult beetles do emerge from a tree, 

they are relatively small and inconspicuous. 

Once the ash borer was identified, scientists in the United States had little 

information to use in developing a control program. Only two short 

scientific papers were available from Asia that described the beetle’s 

biology and habits. Similar to the Asian longhorned beetle, and in contrast 

to some other agricultural and forest pests, the ash borer is not known to 

respond to chemical lures. This appears to be typical of this family of beetle 

(Buprestidae) and has greatly hampered the management program’s ability 

to define the extent of infestation. 

P. ramorum Similar to the Asian longhorned beetle and the emerald ash borer,

P. ramorum has several biological characteristics that have contributed to 

the pathogen’s spread. First, unlike many forest pathogens, P. ramorum

affects a wide range of host plants—ranging from common forest tree 

species, such as tanoaks and oaks, to common nursery species, such as 

rhododendron and camellias. P. ramorum infects species in more than 55 

plant genera, and the known number continues to grow as more research 

and monitoring is done. On the other hand, not all host plant species are 

equally vulnerable to the pathogen; while some species die from infections, 

others only show symptoms of ill-health. Infected plants act as carriers and 

help spread the pathogen to other plants.

Another characteristic that makes managing P. ramorum difficult is that its 

symptoms can differ widely among host species and often resemble other 

diseases, making visual detection difficult. Symptoms appear seasonally 

and generally are of two types, bark cankers and foliar blights. Bark 

cankers, typically associated with oaks and tanoaks, often appear to be 

16Epicormic shoots are sprouts that emerge from dormant buds along the trunk or branch of 

a tree. They can form in response to stress inflicted upon the tree.
Page 30 GAO-06-353 Invasive Forest Pests

“bleeding” on the trunks of infected trees (see fig. 10). The mortality caused 

by bark cankers can often resemble other conditions known as oak wilt 

and oak decline.

Figure 10: “Bleeding” on Tree Trunk Caused by P. ramorum

 The second type of symptom, foliar blight, appears on host plants—such as 

camellia and rhododendron—as spots or blotches on leaves, or shoot 

dieback. Foliar blight can serve as a reservoir of P. ramorum spores that 

may spread to other plants. Unlike bleeding cankers on oaks, hosts with 

foliar blight rarely die from the infection. Foliar blight can be confused with 

the symptoms caused by common fungi and other pathogens. Regardless of 

what host plant is suspected of having P. ramorum and regardless of what 

symptoms are seen, it is impossible to positively detect P. ramorum

on-site. Samples of potentially infected plants found in nurseries must be 

sent to an APHIS-approved laboratory for diagnostic tests to confirm the 

presence of P. ramorum, which can be expensive and time-consuming. 

Sources: Joseph O’Brien, USDA Forest Service, www.forestryimages.org (left); Cheryl Blomquist, California Department of Food

and Agriculture (right).
Page 31 GAO-06-353 Invasive Forest Pests

In addition to being difficult to detect, and therefore easily spread on 

nursery plants, P. ramorum is able to spread in water. Spores of the 

pathogen can travel in streams or even wind-driven rain or fog, making 

control of the spread very difficult, if not impossible, in the natural 

environment.

Delays in Detecting and 

Identifying the Asian 

Longhorned Beetle, the 

Emerald Ash Borer, and 

P. ramorum Allowed These 

Pests to Become 

Established and Spread

For each of the three forest pests we reviewed, several years elapsed 

between the arrival of the pest and its discovery, thereby giving the pest 

time to become firmly established in the environment. Specifically:

• Asian longhorned beetle: The Asian longhorned beetle is thought to 

have begun infesting trees in New York City in the mid-1980s. However, 

the beetle was not detected until 1996 by a homeowner who noticed 

suspicious holes in one of his trees. The homeowner thought the holes 

were the work of vandals, but upon investigation, government officials 

determined that the damage was caused by the Asian longhorned beetle. 

The beetle was known to APHIS port inspectors who had intercepted 

the beetle twice between 1985 and 1998 in solid wood packing material 

accompanying shipments from China. According to APHIS, inspectors 

probably intercepted Asian longhorned beetle larvae and the larvae of 

related species repeatedly before 1996, and would have taken mitigating 

actions to prevent their entry without needing to identify which species 

they were. However, despite its presence at U.S. ports and the potential 

for damage to natural resources, no systematic monitoring or surveys 

were performed to determine if the beetle had been introduced to the 

natural environment. Had such surveys been conducted, the pest might 

have been found years earlier.

• Emerald ash borer: Government agencies misdiagnosed early 

symptoms of ash mortality in Michigan, thereby giving the emerald ash 

borer a running start that has greatly diminished the likelihood that 

control efforts will succeed. Scientists believe that the ash borer arrived 

in southeastern Michigan by the early 1990s in solid wood packing 

material accompanying products shipped from Asia. For several years 

prior to the detection of the insect, ash trees displayed high rates of 

sickness and death throughout metropolitan Detroit in southeastern 

Michigan. However, observers from government and academia 

attributed the mortality to other causes, including a native borer and a 

disease known as “ash yellows.” A former forest health official with the 

Michigan Department of Natural Resources told us that the department 

did not focus its attention on monitoring the health of trees in developed 
Page 32 GAO-06-353 Invasive Forest Pests

areas within the state, such as suburban Detroit where the ash borer 

first appeared, but instead focused on state-owned forestland. The 

Michigan Department of Agriculture official leading the state’s 

management program told us that agricultural inspectors did not 

identify the pest, in part, because they inspected trees in the fall after 

the ash borers had stopped flying and they did not see the 

inconspicuous exit holes that ash borers had made in the trees. It was 

not until June 2002 that state and university officials actually discovered 

that a nonnative insect was the cause of the tree mortality, and they sent 

a sample of the insect to an expert in Slovakia for positive identification. 

By then, however, the ash borer had already infested thousands of 

square miles. Following the new identification in Michigan, Canadian 

officials confirmed in August 2002 that the ash borer was also in 

Windsor, Ontario. 

• P. ramorum: Nearly 6 years elapsed between the first signs of tree 

mortality and the discovery of P. ramorum as the cause, in part because 

it initially affected trees that are not an economically valued resource. 

Scientists have not determined P. ramorum’s source and do not know 

with precision when it arrived in central California. However, symptoms 

of declining health in tanoak trees were reported as early as 1994. 

Tanoak is one of the main tree species that make up the understory of 

coastal redwood forests, and its acorns support abundant wildlife. 

However, tanoaks are not true oaks, and forestry officials generally 

consider them to be a weed species with little economical value. In 1997, 

when coast live oaks, an abundant and valuable landscape tree, began to 

show similar symptoms, local officials and the public called for a 

concerted effort to identify the cause. The Forest Service and the 

University of California provided the first funds for research in 1999. 

Initially, researchers believed that the symptoms pointed to other 

known possible causes, including insects or a condition known as 

standard oak decline. These possibilities needed to be ruled out before 

progress in addressing the disease could be made. Three forest 

pathologists now working on P. ramorum told us the lack of 

laboratories and forest pathologists at any level of government or in 

California’s universities at the time contributed to the slow progress in 

ruling out these other potential causes and identifying the pathogen. 

Another delay came from resistance within the scientific community to 

accept the pathogen as a member of the genus Phytophthora, which 

typically affect a plant’s roots and do not normally cause the symptoms 

that P. ramorum does. University researchers definitively identified 
Page 33 GAO-06-353 Invasive Forest Pests

P. ramorum as the causal agent in June 2000, but by then the pathogen 

had infested a widespread area.

Although several years elapsed before government agencies identified 

these three pests, a recent case involving the citrus longhorned beetle in 

Washington State illustrates the value of early detection and rapid 

response. Following is a brief description of that situation.
Page 34 GAO-06-353 Invasive Forest Pests

Figure 11: Citrus Longhorned Beetle (Anoplophora chinensis)

Source: USDA Forest Service, www.forestryimages.org.

Early Detection and Rapid Response Contributed to the Likely Eradication of the Citrus Longhorned Beetle

The value of early detection and rapid response is clearly demonstrated in the case of the citrus longhorned beetle (Anoplophora

chinensis). In this instance, infested bonsai trees were inadvertently allowed into the country and shipped to a nursery. However, 

ongoing surveys appear to indicate that quick detection and response prevented the outbreak of a new invasive pest. This event also 

indicates the significant level of effort necessary to eradicate even a relatively small infestation.

In August 2001, the owner of a nursery in Tukwila, Washington, found a citrus longhorned beetle in an imported maple bonsai tree being 

held at the nursery as part of routine 2-year plant disease quarantine. The beetle is native to parts of Asia and is not known to occur in 

the United States. It is related to the Asian longhorned beetle and is known to be a major pest of alder, maple, oak, poplar, and willow 

trees. It is also a pest of fruit trees, including apple and citrus.

Washington State Department of Agriculture employees inspected the nursery and suspected that as many as five beetles, possibly

including pregnant females, had flown from the quarantined trees to trees surrounding the nursery. USDA and the state formed a 

science advisory panel to address the issue of the beetle. The panel included personnel from USDA’s Forest Service, Agricultural 

Research Service, and APHIS; Oregon’s Department of Agriculture; and the University of Washington. The panel made 

recommendations to APHIS and Washington State in October 2001. Citing the small area in which the beetle might be, the panel 

 (continued on the next page)
Page 35 GAO-06-353 Invasive Forest Pests

Stakeholders Believed That 

Quarantines Have Helped 

Slow the Spread of These 

Pests, but Implementation Is 

Difficult

Government quarantines have helped to slow the artificial spread of all 

three forest pests we reviewed by regulating activities that are possible 

conduits for transporting the pests. However, difficulties in quarantine 

implementation have minimized their effectiveness, particularly for the 

emerald ash borer and P. ramorum. Specific problems in implementation 

include a failure to quarantine the correct geographic area or all potentially 

infested materials in a timely fashion because of a lack of information 

about the pests or the extent of the infestations. In addition, because of the 

vast number of potential conduits for transporting the pests to new 

locations—namely, various seemingly benign actions of 

individuals—ensuring full compliance with quarantines is nearly 

impossible. Because of the nature of invasive species, even one quarantine 

violation may lead to a new infestation. As a result, enforcement efforts 

largely focus on public education and outreach as well as inspections. 

Quarantines Have Helped Limit 

the Artificial Spread of Pests

Officials involved with all three pests believed that quarantines have helped 

to reduce the spread of the pests. Quarantines help limit the spread of an 

invasive species by eliminating movement of potentially infested materials. 

However, few stakeholders involved with the emerald ash borer and 

P. ramorum programs (1 of the 11 and 2 of the 16 asked, respectively) 

believed that the quarantines had stopped all artificial movement of the 

pests. Stakeholders involved with the Asian longhorned beetle program 

were somewhat more optimistic about the effectiveness of the quarantines, 

with 4 of 9 stating that they have stopped the artificial spread, 2 saying that 

they have not, and 3 saying that they were uncertain.

Early Detection and Rapid Response Contributed to the Likely Eradication of the Citrus Longhorned Beetle (con’t)

recommended control actions that it said might be considered unacceptably harsh if implemented at a larger scale, including removing 

known and potential host trees and treating remaining trees with insecticides.

In November 2001, the Washington State Department of Agriculture quarantined all properties within a one-half mile radius of the 

nursery. On June 25, 2002, the Governor of Washington declared a state of emergency and authorized the state Department of 

Agriculture to use emergency measures to prevent or abate the infestation. In the summer of 2002, the state, in cooperation with APHIS, 

cut down and destroyed approximately 1,000 possible host trees within about one-eighth mile of the nursery. It also injected insecticide 

into about 1,500 potential host trees within one-quarter mile of the nursery. The state also implemented a revegetation program where 

the trees had been removed, which included giving vouchers to property owners. The state has done extensive surveying of the 

quarantined area in 2003, 2004, and 2005. For example, in 2005, state personnel surveyed more than 32,000 trees in and around the 

quarantined area and found no evidence of beetle activity. The state will continue to survey through 2006 and will end the program if it 

finds no evidence of the beetle. According to APHIS officials, the agency allocated about $2.2 million to Washington under a cooperative 

agreement in fiscal years 2002 through 2005, to carry out surveying, quarantine enforcement, and the eradication program.
Page 36 GAO-06-353 Invasive Forest Pests

Under the Plant Protection Act, if APHIS considers it necessary to prevent 

the dissemination of a plant pest that is new to the United States or not 

known to be widely prevalent or distributed within and throughout the 

United States, the Secretary of Agriculture may take certain remedial 

measures, including quarantine of the plant pest, plant product, article, or 

means of conveyance that

“(1) is moving into or through the United States or interstate, or has moved into or through 

the United States or interstate, and the Secretary has reason to believe is a plant pest or is 

infested with a plant pest at the time of the movement or is in violation or has violated the 

Plant Protection Act;

“(2) has not been maintained in compliance with a post-entry quarantine requirement; or

“(3) is the progeny of any plant, biological control organism, plant product, plant pest, or 

noxious weed that is moving into or through the United States or interstate, or has moved 

into the United States or interstate, in violation of the Plant Protection Act.”

In addition, APHIS may issue quarantines if it determines (1) that an 

extraordinary emergency exists because of the presence of a plant pest that 

is new to the United States or not known to be widely prevalent in or 

distributed within and throughout the United States and (2) that the 

presence of the pest or weed threatens U.S. plants or plant products. 

However, APHIS is only authorized to issue a quarantine under its 

extraordinary emergency authority upon finding, after review and 

consultation with the Governor or other appropriate official of the affected 

state, that measures being taken by the state are inadequate to eradicate 

the plant pest. Under state law, states might limit the movement of 

products within the state and, under certain circumstances, might regulate 

the importation of products from other states.17 

17The Plant Protection Act generally prohibits states from regulating the interstate 

movement of any article, means of conveyance, plant, biological control organism, plant 

pest, noxious weed, or plant product in order to control a plant pest or noxious weed, 

eradicate a plant pest or noxious weed, or prevent the introduction or dissemination of a 

biological control organism, plant pest, or noxious weed, if the Secretary has issued a 

regulation or order to prevent the dissemination of the biological control organism, plant 

pest, or noxious weed within the United States. However, a state may impose prohibitions 

or restrictions if (1) they are consistent with and do not exceed APHIS regulations or orders 

or (2) the state (or political subdivision of a state) demonstrates to APHIS that there is a 

special need for additional prohibitions or restrictions based on sound scientific data or a 

thorough risk assessment.
Page 37 GAO-06-353 Invasive Forest Pests

Quarantines have been used in each of the three forest pest infestations we 

reviewed. In each case, the quarantines identify specific geographic areas 

and plant materials to be regulated. For example, for the Asian longhorned 

beetle and the emerald ash borer, state and federal quarantines regulate or 

restrict the movement of regulated articles, such as firewood and wood 

debris, out of the quarantined areas. The areas include locations where the 

infestations have been found and a buffer area to account for potentially 

undetected spread of the pest. A key part of the federal and state 

quarantines for these pests has been education and outreach to the public 

and businesses that may unwittingly transport the pests. For example, 

firewood dealers, tree maintenance companies, and garden centers have 

been sent educational materials identifying particular pests and explaining 

the regulations and compliance issues. Much effort has also been put into 

educating the general public through displays at community fairs, 

homeowner association meetings, newspaper articles, and public service 

announcements. Program officials with whom we spoke believed that 

public education has helped to slow the spread of the pests and 

emphasized that it is critical to the success of the quarantines. 

Quarantines have played a vital role in containing the spread of

P. ramorum through the movement and sale of nursery plants. The state 

and federal quarantines in California restrict the movement of regulated 

articles, such as certain plants, woody material, and logs, from a 14-county 

area that is known to have natural areas infested with the pathogen. The 

state and federal quarantines in Oregon are similar to the California 

quarantines, but they cover a much smaller area—22-square miles as of 

March 2006. In addition, under a USDA emergency order, APHIS now 

regulates all California, Oregon, and Washington businesses that want to 

ship plants susceptible to P. ramorum interstate; those 

businesses—regardless of whether they are in a quarantined area—must 

demonstrate that their products are free of the pathogen before being 

allowed to ship them. 

Quarantine Boundaries May Not 

Have Been as Inclusive as 

Needed Due to Limited 

Information

While officials believed that quarantines have helped to reduce the spread 

of the three forest pests, quarantine effectiveness is limited by the 

prevailing knowledge about a pest and the extent of the infestation. 

Quarantines must be based on sound scientific information because, as 

regulatory tools, they can have significant impacts on businesses, 

individuals, and the economy. For example, the quarantines on plant 

material from potential hosts to P. ramorum have resulted in the 

destruction of over $4 million worth of products in from one nursery in 

California. However, as we have previously discussed, much was unknown 
Page 38 GAO-06-353 Invasive Forest Pests

about the three pests when they were first discovered. As a result, 

quarantines were, in hindsight, conservative in their inclusion of areas to be 

regulated and, in the case of P. ramorum, in the plant material that was 

initially regulated. 

Regarding the Asian longhorned beetle, as surveys found new infested 

trees, the management team of federal, state, and local officials discussed 

and agreed upon new quarantine boundaries using protocols that 

accounted for known biological characteristics of the beetle and data on its 

dispersal patterns. Fortunately, the Asian longhorned beetle does not move 

quickly; therefore, infestations did not grow very rapidly during the time it 

took to definitively identify the extent of the infestations. This was not the 

case, however, with the emerald ash borer. Michigan imposed its initial 

quarantine for five counties in July 2002, not realizing that the infested area 

was already much larger than that. Similarly, USDA did not quarantine the 

interstate movement of ash material until October 2003, even though Ohio 

had discovered the beetle in February 2003, and it was likely to have been 

in Ohio for several years. Not having the infested area fully quarantined 

increases the chances that infested material will be moved to uninfested 

areas, either within the state or to new states.

Although P. ramorum was detected from “bleeding” oaks and tanoaks in 

June 2000, Oregon issued an emergency quarantine for California in 

January 2001. California and APHIS imposed their first quarantines in May 

2001 and February 2002, respectively.18 Program officials attributed at least 

part of the time lag in establishing the quarantines to the lack of knowledge 

about the pathogen—specifically, knowledge on how the pathogen was 

spread. State and federal governments must continue to adjust their 

quarantine regulations as scientists identify additional host and associated 

host plants in the natural environment. Initially, P. ramorum infestations 

were seen primarily in the natural environment, and stakeholders believed 

that if nurseries were infected it was because of exposure to infested 

natural areas. As a result, the original state and federal quarantines placed 

regulations on nurseries only within the quarantined area. These 

regulations required nurseries to enter into compliance agreements 

whereby they would certify that host and associated host plants were free 

of P. ramorum before shipping them outside of the quarantined area. At 

18The California State Board of Forestry declared known areas of infestation to be “zones of 

infestation” in April 2001, thereby effectively regulating all timber harvesting plans in those 

zones. 
Page 39 GAO-06-353 Invasive Forest Pests

that time, nurseries outside of the quarantined area were not regulated and 

could freely ship host plants, because officials did not believe that they 

posed a high risk of artificially spreading P. ramorum. However, in May 

2003, an investigation of infested camellias found within the quarantined 

area determined that the infected plants had come from a nursery outside 

of the quarantined area. The origin of the infestation in that nursery was 

unknown, and no P. ramorum was detected in the surrounding natural 

environment. Subsequent P. ramorum detections were made in nurseries 

outside of the quarantined areas in California and Oregon as well as the 

first case of P. ramorum in Washington (and British Columbia). Because 

surveys did not find the pathogen outside of these nurseries, the state and 

federal agencies did not establish quarantines in these areas. However, the 

finds did start a process that has led to restrictions on the interstate 

movement of nursery stock from nurseries outside of the quarantined 

areas.

Enforcing Compliance with 

Quarantines Is Difficult

In each of the three forest pest species we reviewed, actions of 

individuals—such as moving firewood or even hiking—can result in 

transporting the pests to new locations. As a result, educating the public 

about activities that could spread the pests and then enforcing compliance 

with the quarantine are daunting tasks. For example, millions of ash trees 

in Michigan have died, creating a supply of firewood in a state where 

firewood is a large commodity. According to stakeholders with whom we 

spoke, the greatest risk of artificial movement of the emerald ash borer 

comes from the movement of firewood. The people likely to move 

firewood, including residents traveling to campgrounds or vacation homes 

and small firewood dealers, comprise a large and diverse population that is 

hard to define and reach with quarantine enforcement efforts. A similar 

situation exists in New Jersey and New York where movement of firewood 

or wood debris could easily spread the Asian longhorned beetle to new 

locations. 

Quarantines for P. ramorum are even more difficult to enforce because the 

pathogen can be spread in several ways. P. ramorum’s natural infestation is 

in an area known as the wildland-urban interface, which is an area where 

houses meet or intermingle with undeveloped wildland, including several 

state and national parks, and that is estimated to have over 7 million 

residents. In addition to transporting infested firewood or debris, 

P. ramorum can also be spread in soil that is inadvertently moved on 

shoes, bike or car tires, or other equipment. Although state and federal 

agencies and nongovernmental organizations have produced several 

pamphlets to teach the homeowner, arborist, fire fighter, recreational land 
Page 40 GAO-06-353 Invasive Forest Pests

user, forest product gatherers, and others about how to decrease the risk of 

spreading the pathogen outside of the infested area, it is impossible to 

reach each individual who might come in contact with it. 

While stakeholders believed that outreach efforts have helped educate the 

public about the dangers of individual actions, such as moving firewood, it 

is not possible to stop all illegal or uninformed behavior. Potentially, all it 

takes is one piece of infested firewood or contaminated soil to start a new 

infestation.

Agencies Lack Effective 

Technologies for Detecting 

and Eradicating These 

Forest Pests

Government agencies lack effective technologies to address the three 

forest pests we reviewed. Over three-fourths (29 of 37) of the pest 

managers we interviewed said that government agencies do not have the 

technological tools—such as detection, eradication, or prevention 

methods—to effectively manage these forest pests.19 Detection methods for 

these pests consist largely of visual observations and, in the case of

P. ramorum, costly laboratory diagnostics. Such methods are not always 

effective, are time-consuming, and may have resulted in slower than 

desired management responses because of the time it takes to delineate 

infested areas. Current eradication methods for these three pests are 

limited to destroying infested trees and plant material—a 

resource-intensive action that is not practical on large infestations, such as 

the emerald ash borer or P. ramorum in California; destruction has been 

effective with the Asian longhorned beetle because many fewer trees have 

been infested. Although some preventative chemical treatments have been 

shown to be effective on the Asian longhorned beetle and emerald ash 

borer, these treatments are only used on the beetle because they are cost 

prohibitive when used on a larger scale. Research is under way to address 

these gaps. 

Delineating Infested Areas Is 

Resource Intensive and Not 

Always Reliable

Relying on visual detection has hampered thorough and rapid delineation 

of the infestations for all three forest pest species. For all three species, 

visual observations are the first sign of a potential problem. With the Asian 

longhorned beetle and the emerald ash borer, telltale signs include exit 

holes on tree trunks and branches. In addition, holes in which female Asian 

longhorned beetles lay eggs—known as oviposition sites—can also be a 

19Four of the 9 Asian longhorned beetle stakeholders, all 12 of the emerald ash borer 

stakeholders, and 13 of the 16 P. ramorum stakeholders we interviewed noted the lack of 

control technologies.
Page 41 GAO-06-353 Invasive Forest Pests

sign of infestation. However, in some cases, these visual signs of infestation 

may be very high in trees and not visible from the ground or inconspicuous 

because of their small size. As a result, ground-based surveys can often 

miss signs of infestations. For example, program officials stated that the 

effectiveness of visual observations of the Asian longhorned beetle from 

ground surveys were only about 30 percent accurate. Because of this, 

managers for the Asian longhorned beetle used bucket trucks and sought 

assistance from “smoke jumpers,” (i.e., forest firefighters accustomed to 

climbing trees) and commercial tree climbers to improve surveying 

success. As a result, the effectiveness of visual inspections more than 

doubled. Surveys for the emerald ash borer also look for symptoms of 

infested trees, such as thinning crowns and dead branches. However, these 

symptoms appear gradually and may not provide rapid evidence of an 

infestation. In general, however, visual observations are still 

time-consuming and resource-intensive, particularly for widespread 

infestations, such as the emerald ash borer and P. ramorum. For 

P. ramorum, visual observations are just the first step in identifying 

potential infestations. To confirm the pathogen’s presence, plant material 

must be sent to a laboratory for analysis. This process adds considerably to 

the time and cost required to make positive infestation determinations. 

Another option for identifying where pests occur is through the use of 

chemical lures that would attract beetles, borers, or other target pests if 

they were nearby. However, neither the beetle nor the borer responds to 

any known chemical lures. The emerald ash borer program uses what are 

known as “trap trees” to detect the pest. Trap trees are ash trees that have 

had a large strip of bark removed from the trunk. The premise is that 

wounded trees give off chemical signals that might attract the ash borer. 

The trees are later cut and inspected for ash borer larvae. However, 

government agencies have not clearly shown that trap trees attract the 

beetles. 

Research into traps, lures, acoustic devices, and remote sensing is ongoing 

to help with detection of the Asian longhorned beetle. Research is also 

under way to develop traps for the emerald ash borer that use chemical 

attractants. In addition, research is under way to develop better methods 

for detecting P. ramorum in the field.

Methods for Eradicating Pests 

Are Limited to Destroying 

Infested Material

For each of the three forest pest species we reviewed, the only effective 

eradication method is to destroy the infested tree or plant material as well
Page 42 GAO-06-353 Invasive Forest Pests

 as nearby trees and plants suspected of being infested.20 There are no 

chemical or biological treatments available to effectively kill the pests on a 

broad scale. In total, hundreds of thousands of trees and over 1 million 

nursery plants have been destroyed because of the three pests. For the 

emerald ash borer and the Asian longhorned beetle, infested trees are cut 

down, chipped to a very small size to kill any insect life stages that may be 

inside the tree, and then burned. This method is obviously very expensive 

and only practical on a relatively small scale. Due to the relatively small 

size of the Asian longhorned beetle infestations, cutting and burning has 

been used wherever infested trees were found. (Over 8,000 trees have been 

removed.) Conversely, for the emerald ash borer, managers have used 

cutting and burning selectively—although still removing hundreds of 

thousands of trees—by focusing on small, outlying infestations and at the 

perimeter of infestations in an attempt to contain the pest to specific areas. 

This approach lost momentum in January 2006, however, when the Indiana 

Department of Natural Resources announced that it no longer would 

require or fund the removal of infested trees because it did not believe that 

removal was working. Similarly, in February 2006, the Governor of Ohio 

announced that the state would be able to focus its eradication efforts only 

on extreme outlier infestations because of a lack of federal funding.

In Oregon, trees infested with P. ramorum were first detected in 2001 in a 

relatively small forest setting. According to the Oregon Department of 

Forestry, the infested acreage was initially determined to be 40 acres but 

has grown to 88 acres. This area was clearcut, and host plants were burned 

to destroy the pathogen. However, cutting and burning is not practical in 

California because the infested areas are so large and are intermixed with 

residential areas and old-growth redwood forests. In California, most tree 

removal is performed to remove dead and dying trees that pose safety 

hazards. One exception to this occurred in Humboldt County, California, in 

2004 when a suppression project removed infected California bay laurel 

trees in an effort to limit the pathogen’s spread. 

Destroying infested plants is routinely used to control P. ramorum in the 

nursery or “artificial” environment. There are more than 55 plant genera, 

many of which are sold to contractors and the public, which may transport 

20By “eradication,” we mean the actual killing of pests that are infesting trees and plants. We 

recognize that there are other important components of a management program, including 

surveys, quarantines, preventive treatments, and public outreach, that may help reduce their 

spread.
Page 43 GAO-06-353 Invasive Forest Pests

the pathogen. If an infestation is found at a nursery or garden center, 

federal and state regulators inspect the facility to determine how much 

plant material needs to be destroyed to avoid spreading the pathogen to 

other locations. Such widespread destruction represents a huge loss to the 

nursery producer, particularly smaller operators. 

Research is ongoing in the area of chemical treatments to identify methods 

to kill these pests without requiring the removal and destruction of infested 

trees and plants. However, chemical treatments are problematic when used 

as a curative treatment for nursery plants against P. ramorum. For 

example, while fungicides are often used in nurseries to guard against 

pathogens and diseases, such treatments can retard the development of 

symptoms in already infected plants, thus effectively masking symptoms 

until such time that the effects of the treatments wear off. Consequently, 

such fungicides are not allowed on P. ramorum host plants that a nursery 

is holding to be destroyed because it may undermine detection of the 

pathogen.

Research is under way to identify possible biological controls for the 

emerald ash borer, the Asian longhorned beetle, and P. ramorum.

21 Some 

biological agents for the three pests show promise, but more research is 

needed. Biological controls have been a relatively effective treatment 

alternative to combat other invasive species, such as gypsy moth, on a large 

scale. However, it takes many years of testing before USDA will approve 

the use of biological controls with confidence that they will not prey on 

native species or create other problems. Research also is under way on all 

three species to better understand their biology and how they spread so 

that more effective management tools can be developed. 

Preventative Treatments Are 

Only Practical in Limited 

Applications

Chemical treatments are available that can be used on uninfested host trees 

surrounding an area that has been infested with any of the three forest 

pests we reviewed, in order to prevent or reduce subsequent infestation. 

These treatments have been used extensively by the Asian longhorned 

beetle program. To help ward off beetle infestation, a pesticide is injected 

into the ground or trunk of a tree near infested areas in the spring or fall; 

the process must be done on an annual basis for a minimum of 3 years to be 

effective. According to the national Asian longhorned beetle program 

21“Biological control” is the use of an animal, insect, or disease to reduce the population of 

an invasive species. Ideally, the controlling animal, insect, or disease affects only the 

targeted species.
Page 44 GAO-06-353 Invasive Forest Pests

manager, preventative chemical treatments provide effective control for 

the beetle when used as part of an integrated pest management approach. 

In contrast, preventative treatments have been used to just a limited extent 

on P. ramorum and the emerald ash borer, primarily by homeowners to 

protect valuable landscape trees, because the treatments are not practical 

or cost-effective on a larger scale. 

Insufficient Funding Has 

Delayed Eradication of the 

Asian Longhorned Beetle 

and Threatens Containment 

of the Emerald Ash Borer 

and P. ramorum

The federal government has provided the vast majority of the funds for 

controlling the three forest pests we reviewed, although funding limitations 

threaten the success of these programs. A large percentage of the federal 

funding for the pests has come from the Commodity Credit Corporation 

(CCC) to supplement congressional appropriations to APHIS’s emerging 

plant pest program. However, program managers have noted that 

reductions in funding levels in both of these funding sources have pushed 

the expected eradication date for the Asian longhorned beetle out 5 years 

and have raised concerns about their ability to contain the emerald ash 

borer and P. ramorum. Reducing investments in control and eradication 

activities means that these pests will persist in the environment and may 

potentially spread to new locations, perhaps resulting in larger 

expenditures in the long run than if these infestations had been addressed 

more aggressively in the short term. 

Federal Funding for These Three 

Pest Programs

For the three pests we reviewed, the federal government has provided the 

majority of funding for programs to address the infestations, primarily 

through the CCC and appropriations to APHIS’s emerging plant pest 

program. The Secretary of Agriculture, in connection with an emergency in 

which a plant pest threatens any segment of U.S. agricultural production, 

may transfer funds from CCC or other available USDA appropriations for 

the arrest, control, eradication, and prevention of the spread of the plant 

pest and related expenses. Use of CCC funds for pest management is 

significant. The Congressional Research Service reported that from 1998 

through June 30, 2004, CCC transfers for all pest and disease management 

were more than the amounts appropriated for those activities ($1.52 billion 

versus $1.32 billion). Over $420 million of federal funds have been budgeted 

for the three forest pests we reviewed (see figs. 12, 13, and 14). 
Page 45 GAO-06-353 Invasive Forest Pests

Figure 12: APHIS Funding for the Asian Longhorned Beetle Program, by Source, for 

Fiscal Years 1997-2006

Notes: 

For fiscal years 1997 and 1998, funding came from APHIS's contingency fund. 

The appropriation in fiscal year 2001 was from APHIS’s Miscellaneous Pest line item.

0

10

20

30

40

50

60

Total funding

Emerging plant pests appropriations

Commodity Credit Corporation funding

1997 1998 1999 2000 2001 2002 2003 2004 2005 2006

Source: APHIS.

Dollars in millions

Fiscal year
Page 46 GAO-06-353 Invasive Forest Pests

Figure 13: APHIS Funding for the Emerald Ash Borer Program, by Source, for Fiscal 

Years 2002-2006

Note: The Forest Service has also provided funding for emerald ash borer program activities, including 

tree planting, research, and projects intended to help businesses obtain economic value from ash 

trees before they become infested. From fiscal years 2002 through 2005, the Forest Service’s State 

and Private Forestry Program and Research and Development Program allocated approximately $15.5 

million for these activities. In fiscal year 2006, the Forest Service has about $3.1 million in budget 

authority for these programs. 

0

10

20

30

40

50

Total funding

Emerging plant pests appropriations

Commodity Credit Corporation funding

2002 2003 2004 2005 2006

Source: APHIS.

Dollars in millions

Fiscal year
Page 47 GAO-06-353 Invasive Forest Pests

Figure 14: APHIS Funding for the P. ramorum Program, by Source, for Fiscal Years 

2001-2006

Notes: 

Congress appropriates funds to an APHIS contingency fund that the APHIS administrator has 

discretion to use for emerging problems.

The Forest Service has provided funding for P. ramorum activities since fiscal year 2000. The focus at 

that time was on research to determine the causal agent of P. ramorum. From fiscal years 2000 

through 2005, the Forest Service’s State and Private Forestry Program and Research and 

Development Program have provided over $17 million for program activities, including research, risk 

analyses, and national monitoring and surveying efforts, and eradication efforts in Oregon. The Forest 

Service also has provided funding for the California Oak Mortality Task Force, a coalition of public and 

private stakeholders that provides public outreach and education efforts. For fiscal year 2006, the 

Forest Service has budgeted $2.7 million for continued P. ramorum program activities. In addition, 

other USDA agencies, such as the Agricultural Research Service and the Cooperative State 

Research, Education, and Extension Service, have provided over $3.5 million since fiscal year 2002 for 

research and public education and outreach efforts for the program. 

States also provide funding for forest pest management actions, although it 

is generally much smaller than the federal investment. For the emerald ash 

borer, Indiana, Michigan, and Ohio have provided matching funds totaling 

about 2 percent of the funds that APHIS has provided from 2003 through 

2005. For the Asian longhorned beetle, New York, New Jersey, and Illinois 

have contributed matching funds totaling about 17 percent of the funds that 

0

5

10

15

20

Total funding

Contingency fund

Emerging plant pests appropriations

Commodity Credit Corporation funding

2001 2002 2003 2004 2005 2006

Source: APHIS.

Dollars in millions

Fiscal year
Page 48 GAO-06-353 Invasive Forest Pests

APHIS has provided from 1997 through 2006. The P. ramorum program has 

obtained the largest nonfederal contribution as a percentage, with 

California contributing matching funds totaling about 34 percent of the 

funds that APHIS provided from 2002 through 2006.

All but 4 of the 37 stakeholders we interviewed believed that it is 

appropriate that the federal government bear the primary financial 

responsibility for dealing with these pests. A common comment from 

stakeholders was that APHIS is the nation’s first line of defense in 

preventing invasive pests from entering the country, and if a pest should 

enter the country and become established, states should not be expected to 

bear the primary burden of addressing the consequences. However, 

stakeholders also believed that the states should bear part of the financial 

responsibility. Most did not have specific suggestions for what they 

believed would be an appropriate split between federal and state funding, 

although those that did have an opinion said that the state share should be 

anywhere from 0 to 50 percent. Others said that cost share arrangements 

should be based on the circumstances of a particular pest. In July 2003, 

APHIS published a proposed rule that would have established criteria for 

determining the federal share of the financial responsibility relative to 

states and other cooperators in a plant pest or animal disease emergency. 

However, the agency did not finalize the rule in accordance with a 

prohibition on the use of appropriated funds to finalize the proposed rule.22

Federal Funding Constraints 

Raise Concerns about Achieving 

Program Goals

Program officials involved with management of the three pests told us that 

either funding has not been what is needed or that they are concerned 

about the prospects for maintaining adequate programs because of funding 

constraints. Without sustained funding, containing the spread of the 

emerald ash borer and P. ramorum will be difficult, and eradicating the 

Asian longhorned beetle will take longer. In addition, the longer these pests 

are allowed to persist in the environment, the greater the risk that they may 

spread to new locations and the more expensive management programs 

could become. 

The Asian longhorned beetle program illustrates the consequences of 

inadequate and inconsistent funding on the time frames for and total cost 

of eradication. Specifically, in fiscal year 2002, program funding was cut by 

about $20 million and remained at close to that level in fiscal year 2003 (as 

22See Consolidated Appropriations Act, 2004, Pub. L. No. 108-199, §761 (2004). This 

prohibition has also been included in subsequent appropriations legislation.
Page 49 GAO-06-353 Invasive Forest Pests

shown in fig. 12). This caused program officials to terminate tree climbing 

and bucket surveys in New York, severely reduce chemical treatments of 

trees in New York from a planned 143,000 trees to 17,570 actually treated 

(an 88 percent reduction), eliminate funding for restoration activities in 

Illinois and New York, and drastically reduce funds for research in fiscal 

year 2003. Program officials told us that this resulted in their target date for 

eradication being pushed out from 2009 to 2014. However, this assumes 

that they will receive about $48 million per year for each of these years. 

While funding was restored to nearly that level in fiscal year 2005, the fiscal 

year 2006 appropriation is just under $20 million. Program managers told 

us that in addition to the risk of additional spread of the beetle during a 

longer eradication program, they have estimated significant cost savings if 

the beetle is eradicated sooner. They said that, compared with a $30 million 

funding level, sustaining funding at the $48 million per year level would 

(1) allow eradication by 2014 instead of 2020 and (2) save APHIS over $63 

million; New York City about $36 million; and the state of New York about 

$12 million in avoided future costs, such as the disposal of wood debris 

from infested trees and the enforcement of quarantine restrictions.

It appears that a similar situation is occurring with the emerald ash borer. 

Stakeholders we interviewed raised concerns that funding for the emerald 

ash borer program is not adequate to achieve the goal of limiting the 

infestation to Michigan. In fiscal year 2005, the program received just over 

one-half of what was estimated to be needed, and the outlook for fiscal 

year 2006 looks similar; Congress appropriated $10 million to APHIS for the 

program, but it is unknown whether the Secretary of Agriculture will also 

transfer CCC funds. The $10 million appropriation is about one-third the 

amount that the program had estimated it would need. The APHIS national 

program manager for the emerald ash borer told us that funding shortfalls 

such as this limit tree cutting in infested sites, which would likely 

contribute to the artificial and natural spread of the pest. Program officials 

from Michigan and Ohio confirmed that their states will not be able to 

remove trees in key infested areas unless funding is increased. 

Nearly all stakeholders we interviewed also raised concerns that funding 

for the P. ramorum program has not been adequate to achieve the goal of 

limiting the infestation in either the natural or nursery environments. 

Funding for this program has varied significantly over the past several 

years in response to the resources needed to conduct intensive nursery 

surveys. For example, funding increased dramatically in fiscal year 2004 in 

response to the discovery that California nurseries had shipped infected 

plants to other states. Part of the reason for subsequent funding declines 
Page 50 GAO-06-353 Invasive Forest Pests

could be because fewer infested nursery shipments had been detected. The 

overall funding available from APHIS for fiscal year 2006 has dropped to 

about $3.1 million, and no CCC funding has yet been made available. This is 

the lowest level of funding since the nationwide shipment of infested plant 

materials in 2004. However, program managers have not developed an 

estimate for funding needed to battle the pathogen. Therefore, it is unclear 

what impact this funding reduction will have on the program. 

In addition to the level of funding, some officials with whom we 

spoke—who were primarily involved with the emerald ash borer 

program—discussed problems with the timeliness of when they actually 

received the funds. CCC funds can be transferred any time during the year, 

but program officials told us that they frequently received them after the 

optimal season to carry out certain preventive and control actions, such as 

tree removal or chemical treatments. For example, the national program 

manager for the emerald ash borer commented that if funding does not 

reach the program within the first few months of the fiscal year, it makes it 

very difficult to plan activities, contract for these activities, and hire and 

train personnel not knowing if the program will have sufficient funding 

received in a timely fashion. Another complaint about funding was the 

impact of the inconsistent amounts the programs receive from year to year. 

This reduces the ability of the managers to plan in advance for announcing 

contracts and securing labor.

Finally, the extensive use of CCC funds for ongoing pest management 

programs has been debated within the federal government. In particular, 

the Office of Management and Budget (OMB) has expressed concerns with 

congressional appropriations committees for their not fully funding pest 

eradication programs, thereby necessitating the transfer of CCC funds.23

OMB has called the use of CCC funds for anything but unforeseen 

emergencies, and especially for ongoing eradication programs beyond the 

1st or 2nd year, “backdoor financing” that avoids the discipline of the budget 

process. In contrast, congressional appropriations committees have 

consistently reiterated that the Secretary should use the authority to 

transfer CCC funds for animal and plant health emergencies. One reason 

cited by Congress for continued use of the CCC fund is that the money is 

available for use until expended—so-called “no-year money”—whereas 

appropriated funds must be obligated within the fiscal year for which they 

are appropriated. This makes use of CCC funds more flexible in responding 

23OMB Statement of Administrative Policy on S. 1427 (Nov. 5, 2003).
Page 51 GAO-06-353 Invasive Forest Pests

to the often dynamic situations in dealing with invasive species.24 Notably, 

as of February 2006, USDA had not announced any plans to transfer CCC 

funds to any of the three pest programs we reviewed for fiscal year 2006. 

Forest Health 

Monitoring Does Not 

Adequately Address 

Urban Forests

USDA conducts a number of monitoring programs that are intended to 

identify forest health issues, including the presence of invasive species. 

However, because these programs do not adequately address urban forests, 

they did not detect the three forest pests we reviewed or other pests. 

Monitoring in urban areas is important because they are common 

destination points for internationally traded cargo that is a frequent 

pathway for pests. Delays in detection and identification allowed the three 

forest pests we reviewed to become established and spread before control 

efforts could begin. 

USDA Forest Health 

Monitoring Programs Cover 

a Variety of Geographic 

Areas and Forest Conditions 

USDA has monitored the health of the nation’s public and private forests 

for decades. Some programs are focused on broad issues, such as tree 

species composition and general health conditions, while other programs 

are focused on identifying specific problems. Key monitoring programs are 

described below:

• Forest Health Monitoring Program: The Forest Service’s Forest Health 

Monitoring Program is designed to determine the status, changes, and 

trends in indicators of forest condition on an annual basis; it has been 

conducted since 1990. The program uses data from ground plots and 

surveys, aerial surveys, and other resources to analyze forest health. In 

cooperation with state foresters, the agency conducts aerial surveys of 

more than 700 million acres per year to map tree mortality and 

defoliation. These surveys provide vital information for use in 

identifying, evaluating, and responding to the causes of forest health 

problems. According to the Forest Service, since 2001 the program has 

expanded its efforts in developing and implementing monitoring 

systems for undersampled populations (such as urban and riparian 

forests) and risk-based detection surveys for invasive forest pests such 

as P. ramorum.

24For more on the issue of CCC funding, see Congressional Research Service, Funding 

Plant and Animal Health Emergencies: Transfers from the Commodity Credit 

Corporation (July 30, 2004).
Page 52 GAO-06-353 Invasive Forest Pests

• Forest Inventory and Analysis Program: The Forest Service’s Forest 

Inventory and Analysis Program—begun in 1930—now conducts a 

census of conditions on nearly all public and private forest lands in the 

United States. The program reports on status and trends in forest area 

and location; in the species, size, and health of trees; in total tree 

growth, mortality, and removals by harvest; in wood production and 

utilization rates; and in forest land ownership. Similar to the Forest 

Health Monitoring Program, the Forest Inventory and Analysis Program 

is implemented in cooperation with state agencies and private 

landowners. Traditionally, the Forest Inventory and Analysis Program 

was intended to provide information relevant to the forest products 

industry. In 1999, the Forest Service merged the plot components of 

these two programs into a comprehensive monitoring framework that 

addresses a broad suite of forest health indicators. 

• Nonnative Bark Beetle Survey: In 2001, the Forest Service began a pilot 

of the Nonnative Bark Beetle Survey.25 The program targets 10 nonnative 

bark beetle species, although all bark beetles captured are identified. 

The former national coordinator for the program told us that the agency 

chose to focus on bark beetles for several reasons, including the fact 

that they are often intercepted at ports of entry. Risk assessments have 

shown that bark beetles cause problems in both their native range and 

in new locations, and that, in general, there are effective lures and traps 

for them. According to the Forest Service, funding for the program has 

increased from a starting point of $60,000 in fiscal year 2001 to $350,000 

in each of fiscal years 2005 and 2006.

Working with APHIS and state cooperators, the Forest Service has 

placed traps at more than 300 sites over the course of the program. 

Traps are typically kept at each site for 1 year. The sites have been in 

urban forests and forests around ports and wood-handling facilities and 

were chosen because of their relatively high risk for receiving insects 

from overseas. According to the Forest Service official who served as 

the national program coordinator from 2003 through 2005, the agency 

has shifted the placement of traps away from ports because it realized 

that cargo containers arriving from overseas are often shipped 

unopened further inland. Now, the program concentrates its traps near 

warehouses, landfills or recycling yards (where wooden pallets are 

handled), nurseries, and urban forests where pests that might be hidden 

25The Nonnative Bark Beetle Survey also addresses nun moths.
Page 53 GAO-06-353 Invasive Forest Pests

in solid wood packing material are more likely to be released. He also 

said that APHIS is surveying near ports, so there was no need to 

duplicate its efforts.

Since 2001, the project has detected six nonnative forest insects for the 

first time in the United States. According to the former national program 

coordinator, USDA has not taken management steps for the new finds, 

with the exception of additional surveying to define the extent of their 

infestations. He said that while the program has shown that new 

species can be detected using this method, it has not led directly to any 

successful management actions. On the contrary, the following two 

examples drawn from the six new species discoveries provide further 

evidence of the need for earlier detection and more rapid response. 

• In 2002, the bark beetle survey found a new wood-boring species in 

Georgia, known as Xyleborus glabratus. More traps were set out to 

delimit the extent of the infestation, but few of these beetles were 

found. According to the former national program coordinator, this 

species appears to be different from other bark beetles in that it does 

not respond well to known lures. That fact was not known at the 

time, however, and, according to the former coordinator, the beetle 

became a low priority for the Forest Service. However, in 2003, 

observers noted high mortality in Georgia and South Carolina for a 

common understory shrub known as red bay (Persea borbonia). This 

mortality was later attributed to a fungus associated with the beetle. 

Red bay is related to avocado, leading to concern that the beetle and 

fungus could affect that crop. According to the former coordinator, it 

is not possible to say whether the beetle could have been eradicated 

if a rapid response had been implemented after its discovery in 2002. 

He believed the beetle may have been in the country since the 1990s 

and was already widespread by the time it was detected. At any rate, 

he believed that it is now too late for eradication.

• In 2003, the survey detected a beetle in Colorado and Utah known as 

the banded elm bark beetle (Scolytus schevyrewi). APHIS convened 

a New Pest Advisory Group in July 2003, which recommended 

conducting additional surveys for the beetle. By the fall of 2003, 

surveys had found the beetle in 13 states, and an examination of the 

state insect collection in New Mexico indicated that the pest had 

been in that state since at least 1998. This pest is known to infest 

many tree species in Asia, although it has been found only on elm in 

the United States. Significantly, the beetle could be a carrier of the 
Page 54 GAO-06-353 Invasive Forest Pests

pathogen that causes Dutch elm disease. APHIS has not implemented 

a management program for this species because it is so widespread. 

According to the Forest Service’s director for forest health protection, 

the agency is considering expanding the Nonnative Bark Beetle Survey 

program so that one-third of all states would be participating in any 

given year. The former national coordinator for the program explained 

that some high-risk states would participate more often than once every 

3 years, while low-risk states might participate once every 5 to 10 years. 

He estimated that a national program covering one-third of the states 

and averaging about 16 or 17 sites per state, would cost about $850,000 

per year. This amount would cover the cost of supplies for traps, the 

salaries for surveying crews, the taxonomic expertise needed to identify 

the insects, and data management. He said that, in his opinion, a 

national program of that size would still be only “a drop in the bucket” 

compared with the need. Specifically, he said that there are far more 

high-risk sites that should be surveyed than would be covered by this 

program. He also noted that this program would survey for only bark 

beetles, and that additional funds would be needed to expand to include 

other insect groups.

• The Cooperative Agricultural Pest Survey’s National Exotic 

Woodborer/Bark Beetle Survey. APHIS manages a survey program 

known as the Cooperative Agricultural Pest Survey. The agency 

cooperates with state departments of agriculture to survey for a specific 

list of plant pests, including insects, diseases, and weeds. The focus of 

the survey is on both agricultural and nonagricultural plant pest species. 

The list of species that APHIS and the states have agreed to survey for 

include at least 19 woodborers and bark beetles, including the emerald 

ash borer, the Asian longhorned beetle, and nine of the species targeted 

by the Forest Service program previously described. APHIS also 

encourages survey personnel to record and report detections of other 

forest pests made while conducting the prescribed woodborer and bark 

beetle survey. APHIS state plant health directors coordinate with state 

agencies to select high-risk sites to survey. These sites could include 

facilities that handle solid wood packing material, nurseries and dealers 

receiving shipments of foreign bonsai or other living woody plants, 

urban forests, parks, arboretums, and other high-risk locations. APHIS’s 

survey procedures (1) call for routine reporting of survey data to the 

National Agricultural Pest Information System and (2) lay out specific 

steps for reporting new detections.
Page 55 GAO-06-353 Invasive Forest Pests

• P. ramorum National Nursery Survey and National P. ramorum 

Survey of Forest Environments. In addition to inspections in regulated 

states, the P. ramorum National Nursery Survey and the National

P. ramorum Survey of Forest Environments have contributed to the 

increased detection of infested nursery plant shipments. Started as pilot 

projects in fiscal year 2002, the P. ramorum National Nursery Survey 

and the National P. ramorum Survey of Forest Environments inspect 

high-risk nurseries that received plants from an infested West Coast 

nursery and forests adjacent to those nurseries as well as forests where 

host species are present.26 In fiscal year 2004, the Forest Service funded 

the forest surveys in 37 states and in 39 states for fiscal year 2005. 

Funding for the surveys increased dramatically in fiscal year 2004, 

following the shipment of thousands of infested plants from a nursery in 

Southern California. APHIS coordinates the P. ramorum National 

Nursery Survey with state agriculture departments, while the Forest 

Service works primarily with state forestry or natural resource agencies 

to conduct the National P. ramorum Survey of Forest Environments. 

Positive detections of the pathogen in nurseries trigger what are known 

as “trace backs” and “trace forwards,” where inspectors attempt to 

locate either the origin of the infested plant or its destination if it was 

sold to a customer. In fiscal year 2005, the nursery survey identified 26 

positive detections in 6 states, while the forest survey found no positive 

detections.27 According to the Forest Service director of forest health 

monitoring, the forest survey will be fully funded in fiscal year 2006. 

However, according to APHIS officials, the nursery survey may be 

limited in fiscal year 2006, due to a lack of funding. 

In addition to monitoring forest health issues, the Forest Service developed 

an early warning system in 2004 that can be used to quickly disseminate 

information in the event of a major forest pest occurrence.28 This warning 

system was established pursuant to a requirement in the Healthy Forest 

Restoration Act of 2003 to provide a comprehensive early warning system 

for potential catastrophic environmental threats to forests to (1) increase 

26The focus of the 2002 pilot, the P. ramorum National Nursery Survey, was on nurseries 

that had received known host plant material from Europe, California, or Oregon within the 

past few years; nurseries located in areas where native vegetation included host plants; and 

nurseries that carried listed host plant material. 

27In 2004, the forest survey did find two infected coast live oaks in Golden Gate Park.

28U.S. Department of Agriculture, Forest Service, The Early Warning System for Forest 

Health Threats in the United States.
Page 56 GAO-06-353 Invasive Forest Pests

the likelihood that forest managers will be able to isolate and treat the 

threat before it gets out of control and (2) prevent epidemics that could be 

environmentally and economically devastating to forests.29 This system 

aims to integrate the various resources, programs, and jurisdictions with 

relevant authorities and expertise, including several agencies within USDA, 

the Department of Homeland Security, the Department of the Interior, the 

National Oceanic and Atmospheric Administration, state agencies, 

arborists, and others. The warning system does not create any new 

monitoring or management program; rather, it simply coordinates existing 

efforts. The Forest Service’s Forest Health Protection Program runs the 

early warning system with assistance from a steering committee 

comprising representatives from key organizations and agencies. One 

purpose of the steering committee is to identify steps that are needed to 

improve the early warning system. 

The first step of the early warning system is to identify potential threats 

before they invade new ecosystems. In its early warning system document, 

the Forest Service noted several ways in which a variety of agencies’ 

programs identify these threats, including maintaining databases on 

potential pests that have not arrived; conducting risk assessments to 

evaluate the likelihood that a specific organism may be introduced and 

become established; studying potential pests in their native environments 

so that if they do arrive in this country, more is known about how to 

manage them; and identifying pathways by which invaders may spread, 

such as solid wood packing material and live plants. The program steering 

committee concluded that one way to identify potential threats before they 

invade is to learn more about how potential invasive species will behave or 

react when they encounter probable host trees in the United States. The 

steering committee suggested that one method to do this would be to find 

or even plant trees native to the United States in other countries and then 

survey them to find any pests that attack them.

The second step of the early warning system is detection of actual threats. 

We discussed several detection programs in previous text. The program 

steering committee identified the need to provide managers responsible for 

responding to pest outbreaks with improved communication regarding 

potential pest-caused damages found during regular surveys. The steering 

committee suggested that the early warning network could link 

surveillance efforts to the risks of introduction and establishment to 

29Pub. L. No. 108-148, § 601(c)(2003).
Page 57 GAO-06-353 Invasive Forest Pests

address this need. The steering committee also noted that additional 

taxonomic expertise is needed to ensure that pests are being adequately 

identified. These observations are directly relevant to situations such as 

those created by the three pests we reviewed.

Surveys for Potentially 

Harmful Forest Pests Do 

Not Adequately Cover 

Urban Areas

Many forest pests, including at least two of the three we reviewed, were 

first introduced in urbanized environments. However, while some of 

USDA’s monitoring programs may cover these areas, they do not provide 

adequate coverage. Forest experts with whom we spoke said that, 

historically, urban forests have not been adequately monitored. In addition, 

in 1997 and 2004, the National Association of State Foresters passed 

resolutions stating that there is no systematic inventory and assessment of 

the nation’s urban forest resource. In 1997, the association resolved that 

criteria and standards be established for a nationwide initiative to 

periodically gather comprehensive information relating to the inventory 

and assessment of our urban and community forests. In 2005, the 

association joined with the Forest Service in convening a task force of 

forestry stakeholders to (1) evaluate current urban forest inventory efforts, 

(2) investigate a national continuous urban forest inventory and 

assessment protocol, and (3) propose an implementing strategy. The task 

force has not yet produced a report or proposed strategy.

Following the 1997 resolution by the state foresters, the Forest Service 

initiated a pilot project in 1999 in several states designed to improve urban 

forest health monitoring. The purpose of the project is to acquire 

information about the urban forest, while at the same time establishing a 

nationwide system of urban forest pest detection and forest monitoring and 

assessment. The project has two components. The first component seeks 

to extend the sampling grid of the Forest Inventory and Analysis, which has 

traditionally not sufficiently sampled urban forests. The second component 

seeks to implement a roadside tree assessment using plots established 

within public rights-of-way in urban areas.30 To date, the Forest Service has 

implemented pilot projects for one or more of these stages in Colorado, 

Indiana, Maryland, Massachusetts, New Jersey, Tennessee, and Wisconsin. 

According to the Forest Service’s national program manager for forest 

30The project had a third component that sought to combine the protocols and methods of 

the first two components into a technology transfer effort for the benefit of local 

communities. According to the national program manager, the Forest Service is no longer 

funding that component.
Page 58 GAO-06-353 Invasive Forest Pests

health monitoring, the agency budgeted $850,000 from fiscal years 2001 

through 2005, and received a one-to-one match from the states for the pilot. 

The program manager told us the Forest Service projects a $175,000 budget 

for fiscal year 2006. Funding has come from both the Urban and 

Community Forestry Program and the Forest Health Monitoring Program. 

Since only seven states were covered by this pilot, systematic monitoring in 

urban areas is still not adequate. The director of the Urban and Community 

Forestry Program told us that one way to improve urban monitoring would 

be to survey Forest Inventory and Analysis plots that are in urban areas but 

that are not now surveyed because the Forest Service classifies them as 

“nonforest,” even though they may have trees. The Forest Service estimates 

that extending the Forest Inventory and Analysis to urban sites on a 

rotating basis would cost about $2.5 million per year. The Urban and 

Community Forestry Program director said that there are no guarantees 

that new pests would be found by expanding the inventory, but that there is 

a strong case to be made for doing so because the potential costs of dealing 

with pests, such as the emerald ash borer, once they are established are 

staggering. Another, and perhaps a more likely, benefit of expanded urban 

monitoring is gathering better information on what trees comprise urban 

forests. Knowing what tree species are where will help prepare risk 

assessments related to specific pests. For example, knowing the extent of 

ash trees in urban settings is necessary to be able to calculate the potential 

for losses caused by the emerald ash borer.

Coordination Problems 

Caused Concerns 

among Stakeholders, 

and Communication on 

the Status of Pest 

Responses Is Not 

Adequate 

For each of the three pests, while a majority of the 37 stakeholders with 

whom we spoke told us that appropriate coordination mechanisms are now 

in place, many raised concerns about appropriate affected parties not being 

involved in or informed about key decisions early in the response effort. A 

common theme among the comments was that better early coordination 

would have strengthened the response efforts. New pest response efforts 

could avoid such concerns if attention is paid to the lessons learned from 

the three pest management efforts we reviewed. In addition, we note that 

USDA’s management plans for the three pests do not adequately 

communicate current information to decision makers and the public about 

how recent developments, including funding reductions and the extent of 

the infestations, will affect the prospects for success. 
Page 59 GAO-06-353 Invasive Forest Pests

Stakeholders Generally 

Believed Appropriate 

Coordinating Mechanisms 

Exist, but Suggested 

Improvements That Could 

Aid Future Management 

Efforts

While the majority of the stakeholders we interviewed about each of the 

three pests believed that appropriate coordinating mechanisms were now 

in place, a majority also believed that improvements could be made to 

address problems that were encountered during the pest management 

efforts.31 (By coordinating mechanisms, we mean such things as 

interagency and intergovernmental management teams and panels of 

federal and nonfederal scientists.) Of the 37 stakeholders we interviewed, 

30 stated that the federal and state governments had created appropriate 

coordinating mechanisms to respond to the three pest infestations. Of the 7 

who stated that appropriate federal coordinating mechanisms were not in 

place, 5 were commenting on the P. ramorum program and included 

stakeholders from federal, state, and nursery organizations. While 

generally satisfied, the majority of stakeholders also believed that 

improvements could be made to federal coordinating mechanisms (29 of 

37) and state coordinating mechanisms (22 of 37) to address concerns that 

they identified.32 Implementing actions to address these concerns could 

benefit the management of future pest response efforts. 

The most commonly suggested area for improvement concerned 

coordination among state agencies. Three of the Asian longhorned beetle 

stakeholders, 7 of the emerald ash borer stakeholders, and 8 of the 

P. ramorum stakeholders made comments about state agency 

coordination. While state agriculture agencies typically have primary 

responsibility at the state level for addressing invasive pest infestations, the 

management of those infestations may involve other state agencies, 

including departments of natural resources, forestry, and the environment. 

Several stakeholders commented on the need for state departments of 

agriculture and natural resources to work more closely together. For 

example, one state department of natural resources official commented 

that his department could not convince the state department of agriculture 

31We administered a structured interview to 37 stakeholders—9 involved with the Asian 

longhorned beetle, 12 with the emerald ash borer, and 16 with P. ramorum. The government 

officials included federal, state, and local officials directly engaged in one of the pest 

management efforts; nongovernmental officials included academic scientists with expertise 

in one of the pests and representatives from the nursery industry affected by one of the 

pests and by quarantine regulations.

32Stakeholders who believed that improvements could be made included some who did not 

believe appropriate mechanisms had been created and some who did. All 16 P. ramorum

stakeholders, 7 of 12 emerald ash borer stakeholders, and 6 of 9 Asian longhorned beetle 

stakeholders believed improvements could be made to federal coordinating mechanisms.
Page 60 GAO-06-353 Invasive Forest Pests

to survey for infestations in outlying areas. The result was a delay in the 

discovery of what turned out to be a large number of well-established 

outlying infestations. An APHIS state program manager commented that 

the departments of agriculture and natural resources in his state could have 

worked together better on a program designed to harvest trees for 

productive purposes before they fell victim to the pest. Doing so could have 

helped reduce the spread of the pest. One state official commented that he 

would like to see more work done by state agencies in addition to the 

department of agriculture, and that it would be helpful to have one person 

directing the work of all the state agencies. An APHIS official echoed this 

by observing that it was not clear which state agency has been in charge in 

dealing with one of the pests. Two state officials, 2 Forest Service officials, 

and 2 university research scientists suggested that states need to have a 

systematic response plan in place before an emergency occurs. Some of 

these officials said that such plans should identify who would be involved, 

what their roles and responsibilities would be, and how they would be 

funded. Having such a plan would facilitate a more rapid response to new 

infestations. 

Eleven of the 37 stakeholders commented that coordination among federal 

agencies—primarily, coordination between APHIS and the Forest 

Service—could have been improved during the initial phases of the pest 

responses. Most of these comments—8 of 11—came from P. ramorum

stakeholders. Across the three pests, stakeholders attributed coordination 

concerns in part to the differing missions of the two agencies. For example, 

1 state official said that, in the case of the Asian longhorned beetle 

program, the Forest Service “tends to sit back and watch when the agency 

should be proactive in working with APHIS in addressing invasive pests.” 

Somewhat in contrast, an APHIS official working on the emerald ash borer 

commented that the management team had not made good use of the 

possible contributions of the Forest Service regarding a program intended 

to harvest and use trees before they became infested. This official also said 

that the management team could have made better use of the USDA’s 

cooperative extension agents to educate the public about the pest and its 

potential impact.33 An academic research scientist commented that APHIS 

did not become involved with P. ramorum until the pathogen showed up in 

nurseries, but then did not seek input from the Forest Service in the 

regulatory process. 

33Cooperative extension agents are part of the Cooperative State Research, Education, and 

Extension Service.
Page 61 GAO-06-353 Invasive Forest Pests

Two local government stakeholders also raised a concern about the 

organization of the Asian longhorned beetle program in New York. They 

commented that APHIS had established three work units in New York City, 

with one each in Manhattan, Queens, and Brooklyn. According to these 

stakeholders, the three offices do not consistently record or report data on 

the surveying operations or tree infestations. The local officials said that 

they had difficulty obtaining data from these work units for their own 

analysis. In response to this comment, the APHIS national program 

manager for the Asian longhorned beetle said that, because of its size and 

complexity, there are three work units in New York City managed by state 

and federal supervisors acting as a unified command. The geographic areas 

those work units cover represent unique challenges that at times require 

different approaches. The local officials also expressed the opinion that 

APHIS should have one regional management board for New York and New 

Jersey. Considering the close proximity of these infestations, the 

stakeholders suggested that a single regional management team could have 

sufficed and provided more transparency and consistency in managing the 

beetle. They noted that multiple management teams sometimes took 

inconsistent actions that were noticed and questioned by citizens. The 

APHIS national program manager noted that there are separate 

management boards consisting of federal, state, and local cooperators 

overseeing the programs in New York, New Jersey, and Illinois, and that 

APHIS program managers are represented on all of the boards to ensure 

coordination and consistency. Within each state, strategic actions are 

impacted by state and local authorities that may lead to differences in the 

approach used to execute the eradication protocols in each state. 

Ten of the 37 stakeholders commented that improvements are needed in 

coordination between federal and state agencies. The 10 stakeholders were 

evenly split between the emerald ash borer and P. ramorum programs. 

Some of their comments reflect the challenge of obtaining a consensus 

among different levels of government on how to carry out the management 

program. For example, APHIS officials commented on variations in which 

state agencies regulate the use of pesticides. Specifically, they noted that 

they had more success coordinating pesticide use with state departments 

of agriculture than with a state environmental protection agency. Delays in 

pesticide application could hamper efforts to slow the spread of the pest. 

Those same APHIS officials observed that state officials were at times 

reluctant to use what authority they might have to inspect trees on private 

property because of concerns over “political fallout.” Again, such delays 

could hamper the program’s ability to detect and treat infestations. Another 

APHIS official complained of not getting strong state support for “routine” 
Page 62 GAO-06-353 Invasive Forest Pests

regulatory matters. Two APHIS officials commented that the agency should 

make better use of its cooperative agreements with states to direct those 

states’ activities. Developing more specific cooperative agreements would 

require better coordination between the parties and would increase 

accountability for how federal funds are spent. A state department of 

agriculture manager told us that closer coordination with his APHIS 

counterpart could have reduced differences in interpretation of quarantine 

provisions and, therefore, could have improved enforcement.

Eight of the 37 stakeholders also said that they believed coordination 

would be improved if a wider range of stakeholders were involved in the 

management response to the infestation. Of the 8 stakeholders, 4 were 

speaking about P. ramorum coordination, 2 about the emerald ash borer, 

and 2 about the Asian longhorned beetle. An opinion expressed by some of 

these stakeholders was that responses to pest infestations are more 

effective when all affected or potentially affected parties participate in the 

decision-making process regarding their management. The primary 

mechanism APHIS uses to bring affected parties together and coordinate 

an appropriate pest response is to establish a management team 

comprising federal, state, and local officials as appropriate. Stakeholders 

for each of the pests in our review noted that key affected parties were not 

adequately included in this management process. Some of the affected 

parties that stakeholders believed should be more involved include the 

following:

• other states that are at risk of receiving pests from the infested states;

• industries that are at risk if the pests are not contained, such as 

nurseries and maple syrup;

• local officials who can educate their citizens about the pests and the 

harm that they can cause if left unmanaged, thereby gaining citizen 

cooperation in addressing the pests; and

• nonprofit groups that are involved in forestry activities and can assist in 

pest surveys and public education and outreach.

In response to these comments, the national program manager for the 

emerald ash borer program noted that other states were included in the 

management team as soon as it became clear that the infestation was not 

confined to Michigan, and that adjacent states and affected industries were 

notified of the potential threat. 
Page 63 GAO-06-353 Invasive Forest Pests

The Status, Direction, and 

Resource Needs of Pest 

Response Efforts Are Not 

Clear from Publicly 

Available Management 

Plans 

Because the success of efforts to control invasive species depends, in some 

part, on public participation, the National Invasive Species Council’s 

guidelines on early detection and rapid response systems stress the 

importance of providing timely information to decision makers and the 

public.34 The council identified access to the most recently updated 

scientific and management information as some of the fundamental 

elements of a rapid response system. While much of this information 

remains static once a certain level of knowledge on the pest has been 

reached, specific program information—such as strategic plans, program 

goals and objectives, status of activities, planned future activities, 

estimated eradication date, and identified funding needs—are dynamic and 

should be updated regularly in order to reach decision makers and the 

public in a timely manner. 

The P. ramorum, Asian longhorned beetle, and emerald ash borer 

programs have all issued management plans that are described in the 

bulleted text below; however, timely updates to plans, including estimated 

funding needs, and the status of program efforts have not always been 

available for the three species. For example, plans outlining suppression or 

eradication goals are outdated or incomplete for the three pests. In 

addition, the P. ramorum management plan does not contain required cost 

estimates for the implementation of future efforts necessary to control and 

manage Sudden Oak Death caused by P. ramorum. 

• In December 2004, Congress required APHIS—subject to the availability 

of appropriated funds—to develop a national plan for the control and 

management of Sudden Oak Death caused by P. ramorum.

35 USDA was 

required to address the following three issues in the plan: (1) 

information on ongoing efforts to identify P. ramorum hosts and survey 

the extent to which Sudden Oak Death exists in the United States;

(2) past and current efforts to understand the risk P. ramorum poses 

and the results of control and management efforts regarding Sudden 

Oak Death; and (3) future efforts considered necessary to control and 

manage Sudden Oak Death, including cost estimates for the 

implementation of such efforts. In September 2005, USDA released its 

34National Invasive Species Council, General Guidelines for the Establishment and 

Evaluation of Invasive Species Early Detection and Rapid Response Systems, Version 1

(2003).

35Pub. L. No. 108-488, 118 Stat. 3964 (2004).
Page 64 GAO-06-353 Invasive Forest Pests

strategic plan for P. ramorum that sets a goal of controlling the 

pathogen by prohibiting its introduction into noninfested regions of the 

country, not by eradication. The plan outlines a risk management option 

that identifies preventing the artificial spread of the pathogen through 

commerce, with regulations and quarantines as the most effective 

technique to combat P. ramorum. The plan also identifies the agencies 

responsible for identifying hosts, conducting national surveys, and 

assessing risks—elements of the first two requirements of the law.36

However, although the plan includes a summary of prior federal and 

state funding for P. ramorum, it does not include an estimate of the cost 

of anticipated activities. USDA stated in the plan that future resource 

needs were difficult to project due to the “interaction of complex 

circumstances” but did not identify in the plan what future scenarios 

could take place, the activities associated with those scenarios, or their 

estimated costs. 

• The Asian longhorned beetle management plan for Illinois and New 

York, released in 2000 and available on APHIS’s Web site, estimated 

eventual eradication of the beetle in 2008 for Illinois and 2009 for New 

York. These program goals were based on a series of multiyear 

strategies to contain, control, deregulate, and eventually eradicate the 

beetle, beginning in fiscal year 2001. However, a significant decrease in 

funding in fiscal year 2002, combined with a similar level of funding in 

fiscal year 2003, delayed the multiyear strategies for several years in 

New York, leading APHIS to revise the estimated eradication date for 

New York to 2014 or 2020, depending on funding levels. As we have 

previously discussed, the fiscal year 2006 appropriation for the Asian 

longhorned beetle is significantly lower than the agency believes is 

necessary to meet either the 2014 or 2020 date. However, APHIS has not 

updated the plan for the Asian longhorned beetle to reflect this change 

or to incorporate recently identified infestations in New York City, nor 

does it contain information on the agency’s revised estimate of funding 

needs. According to the national program manager for the Asian 

longhorned beetle, APHIS is in the process of updating the strategic plan 

and anticipates a final version will be available by mid-2006. However, 

the plan is not likely to include information on projected funding needs. 

36APHIS has drafted protocols outlining the response to positive P. ramorum finds in the 

forest and wildland environments. Under the draft protocols, it would be at the states’ 

discretion whether or not to undertake eradication efforts. 
Page 65 GAO-06-353 Invasive Forest Pests

In 2002, following the identification that year of new infestations in 

Jersey City, New Jersey, APHIS developed a separate plan calling for 

eradication in this location by 2008. This APHIS plan—which is not 

available on the agency’s Web site—does not include an estimate of 

funding needs for the work in New Jersey. Because APHIS has not 

updated the 2002 plan, it does not reflect the detection in 2004 of an 

additional large infestation in Middlesex and Union Counties, New 

Jersey. (APHIS has told us that it has established 2011 as the target 

eradication date for these two counties.) The passage of time and the 

changes in the extent of the infestations and actual funding levels have 

caused the latest agency plans for New Jersey and New York to be 

significantly out of date. Without a unified plan that reflects those 

changes, decision makers and the public do not have an accurate 

picture of the status and future of the Asian longhorned beetle 

management program. 

• APHIS’s emerald ash borer program posted on its Web site in May 2005 a 

management plan that spelled out the goal of removing trees infested 

with the pest in three strategically placed gateways: one on Michigan’s 

eastern border with Canada, one along Michigan’s southern border with 

Indiana and northern Ohio, and one south of the Mackinac Bridge 

leading to the Upper Peninsula of Michigan. The immediate objective of 

this strategy is to eradicate the pest in Indiana and Ohio and keep it 

contained within the Lower Peninsula of Michigan. The APHIS plan 

contained an estimate that a long-term eradication program could be 

completed in Indiana and Ohio by 2016, and in Michigan by 2018, 

assuming certain levels of funding. The plan included estimates that 

over $384 million would be needed to achieve the objective, including 

$43 million in fiscal year 2005 and $34 million in fiscal year 2006. 

However, two developments have raised doubts about the agency’s 

estimates. One development is that actual funding in fiscal years 2005 

and 2006 has not reached the levels APHIS believed were needed, and 

the states were not able to complete planned eradication projects. The 

other development is that the program has found additional infestations, 

including some beyond the gateway areas. Given these circumstances, 

in addition to the lack of adequate control technologies, none of the 

emerald ash borer stakeholders we interviewed—including members of 

the management team—believed that eradication is possible. Despite 

these conditions, the management team has not issued an updated plan 

with revised objectives, timetables, or funding needs. One change that 

the team did make was to remove the timetable and cost estimates from 
Page 66 GAO-06-353 Invasive Forest Pests

the publicly available strategic plan, although this does little to convey 

the government’s approach and expectations for the program. 

Science Advisory 

Panels Have Assisted 

with the Pest Response 

Efforts, but There Are 

Concerns about How 

They Were Formed and 

Operated 

Program managers believed that the panels comprising federal and 

nonfederal scientific experts to help the agency respond to each of the 

three pests we reviewed have been useful. USDA does not have specific 

procedures for how the panels should operate, and the agency operated the 

panels for the three pests quite differently. The USDA management 

programs for the emerald ash borer and the Asian longhorned beetle 

created science panels that were tasked with giving advice on management 

approaches. The emerald ash borer team has met at least annually for 4 

years, while the Asian longhorned beetle team met once in 1996 but has not 

met since then. The director of APHIS’s emergency pest program told us 

that the Asian longhorned beetle advisory panel met the objectives of the 

management team when it operated in 1996, and that the management team 

did not need it in subsequent years. He also said that the management team 

has consulted directly with appropriate scientific experts when needed and 

could call the advisory team back together if necessary. In contrast, the 

APHIS P. ramorum program created a science panel that had the charge of 

providing information but not recommendations. In June 2004 in Raleigh, 

North Carolina, APHIS convened a panel of approximately 75 federal and 

nonfederal scientists and regulators from North America and Europe with 

expertise in Phytophthora species. The APHIS national program manager 

for P. ramorum told us that he believed that the panel was helpful, but that 

a panel charged with providing advice and recommendations, perhaps 

under the requirements of FACA, was also needed because of the evolving 

science concerning the pathogen.37 

While the panels have generally been helpful, some stakeholders raised 

concerns about their operation and use. Specifically, 10 of the 37 

37Pub. L. No. 92-463, 86 Stat. 770 (1972) (classified at 5 U.S.C. app. 2). Under FACA, an 

“advisory committee” is defined as any committee, board, commission, council, conference, 

panel, task force, or similar group, or any subcommittee or other subgroup thereof, which is 

established by statute or reorganization plan, or established or utilized by the President or 

by one or more agencies, in the interest of obtaining advice or recommendations for the 

President or one of more federal agencies. The term “advisory committee” does not include 

(1) any committee composed wholly of full-time federal employees or (2) any committee 

created by the National Academy of Sciences or the National Academy of Public 

Administration. Federal advisory committees play an important role in the development of 

public policy and government regulations by providing advice to policymakers on a wide 

array of issues.
Page 67 GAO-06-353 Invasive Forest Pests

stakeholders commented that the use of the panels could have been 

improved. Five stakeholders, collectively addressing all three of the panels, 

stated they thought improvements were needed in how the science panels 

communicated with management teams and with others. For example, 1 

stakeholder criticized USDA for not explaining why the Asian longhorned 

beetle advisory panel was used only at the very beginning of the 

management program. Four stakeholders (including 1 of the 5 just 

mentioned), also collectively addressing all three panels, thought that more 

frequent meetings were needed. One panel member, a federal research 

scientist, told us that a lesson he has learned is that for pests about which 

little is known, there needs to be significant input and consultation from 

scientific experts. He believed that in the case of the emerald ash borer, the 

panel has needed to meet more often than in other pest situations because 

so little is known about this pest.

USDA did not choose to charter the emerald ash borer and Asian 

longhorned beetle advisory panels under FACA, and the scope of our work 

did not include making a legal judgment on whether they should have. 

However, there are certain principles in FACA that, if included in 

operational procedures for pest advisory panels, could help to minimize 

criticism of the sort that we heard. Specifically, the act requires that all 

committees have a charter, and that each charter contain specific 

information, including the committee’s scope and objectives, a description 

of duties, the estimated annual operating costs, and the estimated number 

and frequency of meetings. FACA advisory committee charters generally 

expire at the end of 2 years, unless renewed by the agency or by Congress. 

This encourages the agencies to reexamine whether the committees are 

still needed. FACA also contains general requirements that committees be 

fairly balanced in terms of points of view represented and the functions to 

be performed by the committee, and FACA generally requires that 

committee meetings be open to the public.

Conclusions Forest pests have caused substantial damage in the past and continue to 

pose a serious threat to the nation’s environment and economy. We 

recognize that forest pest managers face a host of challenges—some of 

which are daunting—that constrain their ability to successfully eradicate 

new pests. These challenges include the unique biological characteristics 

of particular species and the lack of existing eradication technologies. 

However, information derived from past infestations and the three forest 

pests we reviewed makes it clear that early detection and rapid response to 

new infestations are critical to improving the likely success of effectively 
Page 68 GAO-06-353 Invasive Forest Pests

controlling invasive forest pests. More specifically, it is likely that without 

broader early detection systems, especially in urban areas because they are 

at high risk of receiving invasive insects and diseases, future infestations 

that are costly and difficult to eradicate will occur. We also found that the 

status of the three pest response efforts was not clearly communicated to 

the public and other key stakeholders, particularly information regarding 

the setbacks that the programs will face due to recent funding reductions. 

Additionally, it was also not clear to us and stakeholders how science 

advisory panels were used and operated in the pest response efforts. Clear 

and current communication on these efforts is important since infestations 

affect many agencies, businesses, and individuals, and the control efforts 

rely on the actions of many entities beyond just the federal players. 

Recommendations To improve federal efforts to detect, manage, and eradicate infestations of 

invasive forest pests, we are recommending that the Secretary of 

Agriculture take the following three actions:

• Expand current efforts to monitor forest health conditions, particularly 

in urban and suburban areas that are at high risk of receiving invasive 

insects and diseases. USDA’s monitoring program should incorporate 

guidance on early detection issued by the National Invasive Species 

Council in 2003.

• Prepare, publish, and regularly update management plans for pests for 

which the department has initiated a management program. The plans 

and their updates should incorporate and describe changes in the extent 

of infestation; progress to date in control and eradication efforts; 

schedules for future control and eradication efforts, given known levels 

of funding; and future long-term funding needs. For the P. ramorum

program in particular, an updated management plan should include the 

elements called for by law that were not included in USDA’s 2005 plan, 

such as an estimate of the cost of anticipated activities. 

• Implement written procedures that broadly define when and how to 

operate panels of scientific experts for the purpose of assisting pest 

management teams, including a discussion on how to determine when 

such panels should be chartered as advisory committees under FACA. 
Page 69 GAO-06-353 Invasive Forest Pests

Agency Comments and 

Our Evaluation

We provided a copy of our draft report to USDA. The department provided 

written comments (see app. VII). Overall, USDA said that the report was 

comprehensive and well written. However, the department expressed the 

viewpoint that the tone of the report was overly critical and gave an 

unfavorable impression of the work done by the agencies to respond to the 

three forest pests. USDA also offered comments on our recommendations. 

With respect to the tone of the report, the department emphasized that little 

was known about these pests before their arrival in the United States, and 

that federal and state agencies did a reasonable job under those 

circumstances. We agree with USDA’s comments that P. ramorum was 

unknown to science before its arrival and that little was known about the 

emerald ash borer, and we made those points in the report. We disagree 

that the Asian longhorned beetle was unknown as a potential threat before 

its arrival. As we describe in the report, larvae of the beetle or closely 

related species had been intercepted many times at U.S. ports of entry prior 

to its detection in 1996. In relation to this point, the APHIS national 

program manager for the Asian longhorned beetle told us that all larvae 

similar in appearance to Asian longhorned beetle larvae are invasive and 

require mitigating action. In general, we agree that the agencies have 

worked hard to control the three pests and believe that our report 

describes the difficult tasks that the agencies face in attempting to 

eradicate them from the environment and accurately portrays the status of 

those efforts. Nonetheless, the fact of the matter is that 2 of the 3 pests will 

likely not be eradicated. In summary, we believe the report fairly presents 

the overall challenges as well as the results of USDA’s efforts.

USDA commented that it did not have major concerns about the three 

recommendations but did not completely agree with them. With regard to 

the recommendation to increase monitoring of forest health conditions, 

particularly in urban and suburban areas, USDA noted that the draft report 

focused only on federal government agencies. The department pointed out 

that state, university, tribal, business, and nongovernmental organizations 

have a role to play in combating invasive species. We agree that these 

entities have a role, and the report does indicate that federal agencies 

collaborate with nonfederal entities on forest health monitoring. Given that 

existing Forest Service and APHIS monitoring programs entail 

collaboration with nonfederal entities, it would not be unexpected that any 

expansion of these monitoring programs would also involve those partners. 

As the lead federal agency, USDA has an important leadership role to play 

in developing and supporting the forest health monitoring capabilities of 

nonfederal entities to achieve more effective results. 
Page 70 GAO-06-353 Invasive Forest Pests

USDA commented that the second recommendation that addresses 

keeping management plans up to date is “a sound business practice which 

we support.” The department stated its belief that a reasonable job was 

done in these instances, given the pressures to accomplish work “on the 

ground.” We agree that the program management teams carried a large 

workload, but continue to believe that more should have been done to keep 

the public informed about the programs’ status and direction. We also 

continue to believe that these and other pest management programs should 

regularly update management plans, and that those plans should contain 

specific information listed in our recommendation. In light of the heavy 

workload that pest management teams are likely to face when responding 

to an infestation, the department may wish to consider developing a 

standardized reporting instrument that would ease the burden on program 

managers, while still providing essential information to the public and 

decision makers about such variables as the overall spread of the pest, the 

location of infestations, the schedule for eradicating those infestations, and 

funding needs.

USDA commented that the third recommendation regarding the need for 

written procedures that broadly define when and how to operate panels of 

scientific experts seemed reasonable. However, the department said that 

the draft report incorrectly implied that, in the three situations we 

reviewed, important people with information to share were not heard. We 

did not independently assess whether the three science panels included the 

correct expertise. However, some stakeholders we interviewed believed 

that the process was not as inclusive or open as it should have been, and 

we concluded that written procedures for the panels could help avoid that 

problem in the future. USDA also commented that chartering a committee 

under FACA would hamper its flexibility in dealing with invasive species 

issues, and, therefore, it disagreed that panels should be chartered under 

FACA. In fact, we did not specifically recommend that committees be 

chartered under FACA, and we agree with USDA that the FACA process 

may hamper an expeditious scientific response to a new infestation. 

Nevertheless, panels of nonfederal experts called on to provide advice to 

USDA may fall under the obligations of FACA, and we continue to believe 

that the department should develop procedures that clarify when and how 

scientific panels can be used in pest response efforts and identify under 

what circumstances a panel should be chartered under FACA. 

As agreed with your office, unless you publicly announce the contents of 

this report earlier, we will plan no further distribution until 30 days from 
Page 71 GAO-06-353 Invasive Forest Pests

the report date. At that time, we will send copies of this report to other 

interested congressional committees and the Secretary of Agriculture. We 

will also make copies available to others upon request. In addition, the 

report will be available at no charge on GAO’s Web sites at 

http://www.gao.gov.

If you or your staff have any questions, please call me at (202) 512-3841 or 

nazzaror@gao.gov. Contact points for our Offices of Congressional 

Relations and Public Affairs may be found on the last page of this report. 

Key contributors to this report are listed in appendix VIII.

Sincerely yours,

Robin M. Nazzaro

Director, Natural Resources 

 and Environment 
Page 72 GAO-06-353 Invasive Forest Pests

Appendix I

Objectives, Scope, and Methodology AAppenednxidexiIs

This report evaluates the federal response to three invasive forest pests—

the Asian longhorned beetle; the emerald ash borer; and Phytophthora 

ramorum (hereafter P. ramorum), the pathogen that causes Sudden Oak 

Death. Specifically, we reviewed (1) the status of efforts to eradicate these 

three species; (2) factors that have affected the success of the response 

programs; (3) overall forest health monitoring programs; (4) the 

coordination of the three pest response efforts among federal and state 

agencies and other stakeholders, and communication about the response 

efforts; and (5) the Department of Agriculture’s (USDA) use of panels of 

scientific experts to aid the responses. We also discuss in appendix VI 

APHIS’s use of risk assessments to support decisions for forest pest 

programs.

We selected a nonprobability sample of these three species because they 

were discovered in the United States relatively recently; they pose a large 

potential threat to the nation’s forests; and the federal government has 

established a program to research, control, and manage them.1

 We also 

deliberately chose both insect and disease pests to learn whether they pose 

different management challenges. Finally, we took into consideration the 

fact that the three pests are in different parts of the country. We considered 

this criterion to be potentially important because states play a major role in 

responding to pest outbreaks.

To determine what federal entities implement projects to address invasive 

forest pests and what sources of funding these entities have, we 

interviewed relevant officials from USDA and the National Invasive Species 

Council and reviewed forest pest literature and Web sites. Within USDA, we 

focused our review on the Animal and Plant Health Inspection Service 

(APHIS) and the Forest Service, the agencies that primarily contribute to 

the prevention and control of invasive forest pests. We also obtained 

relevant information on research activities conducted by USDA’s 

Agricultural Research Service and Cooperative State Research, Education, 

and Extension Service. We recognize that invasive forest pests may affect 

other federal agencies, such as the Department of the Interior. However, we 

focused on APHIS and the Forest Service because these two agencies play 

a larger role in the management of these forest pests. 

1

Results from nonprobability samples cannot be used to make inferences about a population 

because, in a nonprobability sample, some elements of the population being studied have no 

chance or an unknown chance of being selected as part of the sample. 
Appendix I

Objectives, Scope, and Methodology

Page 73 GAO-06-353 Invasive Forest Pests

To analyze the federal responses to the three pests, we reviewed applicable 

laws and regulations pertaining to plant protection and quarantines. We 

also reviewed agency documents pertaining to scientific research, 

regulations and quarantines, program expenditures, cooperative 

agreements, strategic plans, and risk assessments, which included 

estimates of past and potential economic and environmental damage. We 

interviewed national, regional, and state program managers at APHIS; state 

agriculture department officials responsible for implementing the response 

program; Forest Service and state forestry officials; science advisory panel 

members; and researchers from academia. 

We gathered information about invasive forest pest expenditures by federal 

and nonfederal entities from a variety of sources. These included the 

structured interviews and documents provided by agency officials in 

response to our request for funding information. In the instances where 

officials provided us with information through the interview guide, we 

asked if their answers were based on a documented estimate. We 

independently corroborated the data the officials provided in answer to our 

questions, to the extent possible, using other documentation, such as 

cooperative agreements with states and appropriations language. We 

determined that these data were sufficiently reliable for the purposes of 

this report. 

For each of the three pest programs, we contacted officials at federal, state, 

and local government agencies, as well as at nongovernmental 

organizations. We did not attempt to identify or contact all federal, state, 

and local agencies engaged in invasive forest pest management in each 

example. For the three invasive pests we reviewed, we sought to contact 

officials representing APHIS and the Forest Service, state agriculture and 

forestry or natural resources agencies, and local governments as well as 

scientists and other researchers involved with program efforts. In addition, 

for the P. ramorum program, we also interviewed representatives from the 

nursery industry; for the emerald ash borer program, we met with 

individuals in the forest products and firewood industries to gain their 

opinions on federal quarantine regulations. 

We used a structured interview guide to obtain information from federal, 

state, local, and nongovernmental officials, including 9 stakeholders 

involved with the Asian longhorned beetle, 12 with the emerald ash borer, 

and 16 with P. ramorum. The federal officials included APHIS and Forest 

Service employees directly involved in the management programs. The 

state officials included department of agriculture and department of 
Appendix I

Objectives, Scope, and Methodology

Page 74 GAO-06-353 Invasive Forest Pests

forestry or natural resources employees directly involved in the 

management programs. We administered the structured interview to New 

York City and Chicago government officials involved in the Asian 

longhorned beetle program, because of the major role those city 

governments have had in that program. Nongovernmental officials 

included representatives from the nursery industry affected by P. ramorum

and the Asian longhorned beetle, and university scientists with expertise 

related to one of the forest pests. Table 1 lists the three pests that we 

reviewed and the number and affiliations of the stakeholders we 

interviewed with the structured interview guide. 

Table 1: Number of Stakeholders Who Were Administered the GAO Structured Interview, by Pest and Affiliation

Source: GAO.

The structured interview guide asked the officials for their opinions on a 

variety of topics, including state and federal coordinating mechanisms, 

quarantines, public education and outreach, management tools and 

research, funding responsibility, funding needs, risk assessment, potential 

for eradication, impact to the environment, and recommended contacts. 

The structured interview guide consisted of 21 questions asking for a “yes,” 

“no,” or “uncertain” answer and 29 questions asking for open-ended 

answers. For some of the “yes” or “no” questions, respondents gave two 

answers based on their opinion of the overall program as well as their 

opinion on a more specific issue within the program. For example, in 

response to a question about the potential for eradication for P. ramorum, 

several officials responded that eradication was not possible for the entire 

infested area but was possible for a smaller area, such as a less-infested 

state. At times, in answering one question, a respondent would also provide 

an answer to a subsequent question. In our analysis, we assigned their 

answers to the appropriate question. In some instances, respondents did 

Number of stakeholders, by affiliation

Federal agency State agency

Forest pests reviewed APHIS

Forest 

Service

Agriculture 

agency

Forestry or 

natural 

resources

Local 

government 

agency University

Nursery 

industry Total

Asian longhorned beetle 1 1 3 0 2 1 1 9

Emerald ash borer 4 2 3 2 0 1 0 12

P. ramorum 3 3 4 2 0 2 2 16

Total 8 6 10 4 2 4 3 37
Appendix I

Objectives, Scope, and Methodology

Page 75 GAO-06-353 Invasive Forest Pests

not give clear answers to specific questions, and we asked additional 

follow-up questions that were not part of the guide in order to clarify. We 

also asked the stakeholders to recommend other people to interview. 

Appendix II contains the questions from the structured interview guide.

We developed our structured interview guide with the assistance of a GAO 

methodologist. The practical difficulties of asking questions may introduce 

other types of errors (e.g., differences in how a particular question is 

interpreted or the sources of information available to respondents can 

introduce unwanted variability into the responses). We included steps in 

the development of our interview guides to minimize such errors, including 

pretesting the content and format of the interview guides with two 

individuals and making minor changes as appropriate. 

In addition to using the structured interview guide, we also interviewed 

other federal and nonfederal officials in a less formal way. We conducted 

some of these interviews prior to preparing the interview guides. In other 

instances, we used an informal interview method because we did not 

believe that the guides were appropriate for the interviewee. In our report, 

we present information obtained from the informal interviews, but do so 

separately from our presentation of information we obtained through the 

interview guides. 

We made site visits to New Jersey, New York, Michigan, and California to 

observe program activities, such as detection and control efforts and 

inspections of regulated materials. For example, in Michigan we observed 

emerald ash borer trap trees and tree removal operations on both public 

and private land in the gateway between the United States and Canada. We 

also accompanied state and federal officials as they inspected a sawmill 

operation for compliance with emerald ash borer quarantine regulations. In 

California, we observed in a wholesale nursery the use of best management 

practices to reduce the threat of spreading P. ramorum among plants being 

readied for shipment. 

We also discussed APHIS’s use of risk assessments to support decisions for 

invasive species programs. To develop appendix VI on risk analysis, we 

conducted a computerized literature search and identified and reviewed 

articles, as well as domestic and international guidelines, relevant to risk 

analysis for invasive forest pests. To learn about the complex network of 

roles and responsibilities regarding the risk analysis process and risk-based 

management within USDA, we studied information on organizational 

structure provided on APHIS Web sites; conducted interviews with officials 
Appendix I

Objectives, Scope, and Methodology

Page 76 GAO-06-353 Invasive Forest Pests

in APHIS’s Plant Protection and Quarantine office, USDA’s Office of Budget 

and Program Analysis, and USDA’s Economic Research Service; and 

followed up on the interviews with additional questions through e-mails. In 

addition, we reviewed published reports evaluating APHIS’s roles and 

responsibilities in this regard. Finally, we used all sources previously 

mentioned to identify specific risk analysis studies by APHIS for the three 

pests we reviewed in our report. As reported in appendix VI, we found only 

two such studies by APHIS that were related to pests of interest.
Page 77 GAO-06-353 Invasive Forest Pests

Appendix II

Questions from Structured Interview Guide 

Administered to Stakeholders Involved with 

the Three Pest Response Programs ApendxiI

The structured interview guide that we administered to stakeholders 

consisted of the following questions:

Federal and State 

Coordination

1. Do you believe that the federal government has created the appropriate 

coordinating mechanisms to respond to the infestation? (By 

coordinating mechanisms, we mean such things as interagency and 

intergovernmental management teams and science advisory panels.)

2. Do you believe that there are improvements that could be made with 

respect to those federal coordinating mechanisms?

3. If so, what are they?

4. Do you believe that the state government(s) has/have created the 

appropriate coordinating mechanisms to respond to the infestation? 

(By coordinating mechanisms, we again mean interagency management 

teams and advisory panels.)

5. Do you believe that there are improvements that could be made with 

respect to those state coordinating mechanisms?

6. If so, what are they?

7. Please describe any lessons, either positive or negative, that you have 

learned from your experiences with these coordinating mechanisms.

Imposition and 

Enforcement of Quarantines 

8. Do you believe that the state(s) have imposed quarantines for the 

correct geographic areas to achieve the goal of stopping the artificial 

spread of the pest?

9. What do you believe should have been done?

10. Do you believe that the state(s) imposed the quarantines in a timely 

fashion to achieve the goal of stopping the artificial spread of the pest?

11. What do you believe should have been done?

12. Do you believe that the federal government has imposed quarantines 

for the correct geographic areas to achieve the goal of stopping the 

artificial spread of the pest?
Appendix II

Questions from Structured Interview Guide 

Administered to Stakeholders Involved with 

the Three Pest Response Programs

Page 78 GAO-06-353 Invasive Forest Pests

13. What do you believe should have been done?

14. Do you believe that the federal government imposed the quarantines in 

a timely fashion to achieve the goal of stopping the artificial spread of 

the pest?

15. What do you believe should have been done?

16. Do you believe that the quarantines have stopped the artificial spread 

of the pest?

17. If not, what is most needed to improve the quarantines?

18. Do you have any suggestions for legal or procedural changes that could 

improve the quarantine process? 

19. Please describe your suggestions.

20. Please describe any lessons, either positive or negative, that you have 

learned from your experiences with the quarantines for the pest.

Education and Outreach 21. Do you believe that the state and federal efforts to educate the public 

about this pest have helped stop its spread?

22. If not, why not? 

23. What do you believe should have been done?

24. Please describe any lessons, either positive or negative, that you have 

learned from your experiences with education and outreach for this 

pest.

Management Tools and 

Research

25. Do government agencies have the tools they need to manage the pest? 

(When we speak of tools, we include understanding the biology of the 

organism, detection techniques, eradication methods, and other such 

knowledge or technology.)

26. What additional tools are needed?

27. Is research underway to develop those tools?
Appendix II

Questions from Structured Interview Guide 

Administered to Stakeholders Involved with 

the Three Pest Response Programs

Page 79 GAO-06-353 Invasive Forest Pests

28. Please describe any lessons, either positive or negative, that you have 

learned from your experiences with the technological research for 

managing the pest.

Funding Responsibility 29. Do you believe that the federal government should bear the primary 

financial responsibility for addressing an invasive species problem such 

as this?

30. Please explain your answer.

31. Do you believe that the states should bear any of the financial 

responsibility?

32. If so, what do you believe would be a fair cost-sharing arrangement 

between the federal government and the states to address a situation 

such as this pest?

33. Do you believe that the resources devoted to controlling this pest have 

achieved the goal of stopping its spread?

34. What level of funding do you believe is needed per year, regardless of 

the source, to eradicate the pest?

35. What level of funding do you believe is needed in total, regardless of the 

source, to eradicate the pest?

36. What is the basis of your answers for Questions 34 and 35?

37. If your answers to Questions 34 and 35 are based on documented 

estimates, please provide copies or citations.

Funding Mechanisms 38. Do you believe that any improvements are needed in the mechanisms 

or processes through which funding is delivered to the states? 

39. If so, please provide any suggestions you have for improvements.
Appendix II

Questions from Structured Interview Guide 

Administered to Stakeholders Involved with 

the Three Pest Response Programs

Page 80 GAO-06-353 Invasive Forest Pests

Risk Assessment and 

Funding Needs

40. Have the federal or state governments conducted risk assessments to 

estimate the likely costs and benefits associated with managing the 

pest?

41. If yes, please provide sources or citations.

42. Please describe how the risk assessments have been used in making 

resource allocation decisions.

43. Please provide any observations you have on how to improve the 

preparation and use of risk assessments.

Prospects for Success 44. Do you believe it is possible to eradicate the pest?

45. Do you believe that the federal government should strive to eradicate 

this pest?

46. Do you believe that the pest can be eradicated from the entire infested 

area given our current knowledge and level of effort?

47. If not, what do you believe is most necessary to achieve eradication?

48. If you do not believe that eradication is possible, what do you think is 

the likely outcome?

49. Please offer any other comments you might have regarding the 

management of this pest.

50. Who do you recommend we should contact to ask these questions? 

(Additional contacts could, for example, be from your state, from your 

agency, or from stakeholder groups.)
Page 81 GAO-06-353 Invasive Forest Pests

Appendix III

Review of Efforts to Control and Eradicate the 

Asian Longhorned Beetle ApendxiI

Our review of the efforts to control and eradicate the Asian longhorned 

beetle includes a discussion of the origin and spread of the infestation in 

the United States and its potential impacts. We also review the roles of 

federal, state, and local government agencies in addressing infestations and 

describe the management structures and methods they have used to 

control and eradicate this forest pest. Finally, we discuss the current status 

of the Asian longhorned beetle infestation and outline the funds spent to 

date on controlling and eradicating the pest.

Origin and Potential 

Impacts of Asian 

Longhorned Beetle 

Infestations

The Asian longhorned beetle is a large, eye-catching, wood-boring beetle 

that is black with small white spots and long, spotted antennae.1

 It is native 

to countries in Asia, such as Japan, Korea, and China. The beetle spends 

most of its life within the inner wood of a variety of hardwood trees 

tunneling and feeding on the cambium layer, eventually killing the tree. 

APHIS officials believe that the beetle arrived in the United States 

sometime in the mid-1980s in solid wood packing material accompanying 

cargo shipments originating in China and destined for warehouses located 

throughout the country. While inspections have discovered adult beetles at 

about 30 warehouses across the country, the only established infestations 

have been found in a few urban locations. The beetle was first detected in 

Brooklyn, New York, in August 1996. However, APHIS officials believe that 

the beetle had been established in Brooklyn for about 10 years prior to its 

detection. Subsequent infestations were detected in other parts of New 

York; in Illinois (July 1998) and New Jersey (October 2002); and in Toronto, 

Canada (September 2003). Many of the sightings leading to the detection of 

infestations have been by citizens who had been exposed to public 

outreach efforts regarding the beetle. 

Researchers note that the Asian longhorned beetle is a serious threat to 

hardwood trees in both urban and natural forests, and that it has no known 

natural predator in the United States.2

 In a 2000 study of the urban forests 

of nine large U.S. cities, researchers estimated that the beetle could destroy 

as much as 35 percent of U.S. cities’ tree canopy cover and 30 percent of 

1

The Asian longhorned beetle is also known by its scientific name, Anoplophora 

glabripennis.

2

The various trees that serve as hosts for the Asian longhorned beetle include the following: 

maple, boxelder, horsechestnut, buckeye, willow, elm, birch, London plane, hackberry, ash, 

mimosa, poplar, and mountain ash.
Appendix III

Review of Efforts to Control and Eradicate 

the Asian Longhorned Beetle

Page 82 GAO-06-353 Invasive Forest Pests

their trees (1.2 billion trees), with an estimated loss of value of $669 

billion.3

 These estimates do not include the potential adverse impacts on 

the forest products industry (lumber and furniture), maple syrup 

production, fall foliage tourism, as well as the impacts from decreased 

property values; aesthetic damage; and lessened environmental benefits, 

such as cleaning air and water and providing energy-conserving shade. If 

the beetle spreads out of its current urban environment, researchers note 

that it also has the potential to seriously alter the ecological diversity of the 

natural forests in North America, with additional impacts on wetlands. 

Researchers estimate that if the beetle enters natural forests, the potential 

loss could be 71 billion trees, with a value greater than $2 trillion. One 

researcher noted that the beetle has the potential to cause more damage 

than Dutch elm disease, chestnut blight, and gypsy moth infestations 

combined.

Federal, State, and 

Local Roles in 

Controlling and 

Eradicating the Asian 

Longhorned Beetle 

A number of federal, state, and local agencies are involved in managing and 

eradicating the Asian longhorned beetle in the United States, with USDA’s 

APHIS Plant Protection and Quarantine (PPQ) group taking the lead. 

APHIS works with other federal agencies through the use of interagency 

agreements and with state and local governments through the use of 

cooperative agreements. Both the interagency and cooperative agreements 

lay out in detail the roles and responsibilities of each government party as 

well as other matters. The basic roles of the federal, state, and local 

governments are described as follows:

• Federal government: APHIS’s PPQ group works to protect the country 

from the entry of invasive pests and to manage and eradicate invasive 

pests once they are established. PPQ is the lead federal agency 

responsible for surveys, regulatory quarantines, control actions, public 

awareness efforts, and technology development. USDA’s Forest Service 

undertakes forest restoration, research, and public awareness and has 

tree climbers who assist in surveys. USDA’s Agriculture Research 

Service engages in research on management tools. Other USDA agencies 

have also provided personnel to the Asian longhorned beetle program to 

assist in survey and control activities.

3

David J. Nowak, Judith E. Pasek, Ronaldo A. Sequeira, Daniel E. Crane, and Victor C. 

Mastro. “Potential Effect of Anoplophora glabripennis (Coleoptera: Cerambycidae) on 

Urban Trees in the United States.” Journal of Economic Entomology, vol. 94, no. 1 (2001).
Appendix III

Review of Efforts to Control and Eradicate 

the Asian Longhorned Beetle

Page 83 GAO-06-353 Invasive Forest Pests

• State governments: The Department of Agriculture and Markets in New 

York and the Departments of Agriculture in Illinois and New Jersey 

survey, regulate, control, and increase public awareness about the Asian 

longhorned beetle. The New York Department of Environmental 

Conservation regulates pesticides and restores forests. The Illinois 

Department of Agriculture also regulates pesticides. The New Jersey 

Division of Parks and Forestry restores forests.

• Local governments: New York City Department of Parks and 

Recreation, Forestry and Horticulture conducts data management, 

debris disposal, and restoration, facilitating the program within the city. 

The Department of Streets and Sanitation, Bureau of Forestry, conducts 

data management, tree removal, surveying, and restoration, facilitating 

the program within Chicago. Municipal and city governments located in 

Long Island, the suburbs of Chicago, and New Jersey dispose of wood 

debris and conduct public awareness activities. Some local community 

organizations also contribute to public awareness activities.

Management 

Structures and 

Methods Used to 

Control and Eradicate 

the Asian Longhorned 

Beetle

Following the August 1996 detection of the Asian longhorned beetle in 

Brooklyn, an APHIS New Pest Advisory Group met in September 1996 to 

discuss management options and make recommendations regarding 

actions that should be taken to address the infestation. The advisory group 

recommended that APHIS continue to survey for infested trees in 

Brooklyn, impose a quarantine to prevent the spread of the beetle, convene 

a science advisory panel, establish a joint federal/state/local operational 

team, and begin a public outreach campaign in addition to other actions. 

The following month, APHIS convened a science advisory panel to discuss 

the beetle infestations and recommend actions that should be taken to 

control its spread. While recommending actions similar to those set out by 

the New Pest Advisory Group, the science panel also recommended that 

APHIS expand its surveys for the Asian longhorned beetle to a national 

level, pursue research on the beetle’s behavior and management tools to 

control it, and seek complete eradication of the beetle. Following the 

detection of beetle infestations in each of the three states, APHIS/PPQ 

established management teams comprising APHIS, state, and local officials 

to discuss, plan, and carry out an eradication plan.

In April 2000, APHIS officials published APHIS’s revised Asian longhorned 

beetle New Pest Response Guidelines, providing guidance and action steps 

for eradicating infestations. In September of that same year, following 

consultation with state and local officials, APHIS released a plan for 
Appendix III

Review of Efforts to Control and Eradicate 

the Asian Longhorned Beetle

Page 84 GAO-06-353 Invasive Forest Pests

eradicating the beetle in New York and Illinois. After detecting infestations 

in New Jersey in 2002, APHIS released a separate plan for New Jersey that 

same year. On the basis of various guidelines and plans for addressing the 

beetle, the management teams’ efforts to eradicate it have focused on the 

following: 

• Overarching strategy: The strategy of the federal Asian longhorned 

beetle program is to contain and eventually eradicate the pest from its 

current urban and suburban locations through a combination of 

inspections, quarantines, harvesting of infested trees, treating 

uninfested trees with insecticides, and public education. 

• Surveys: Surveys serve the following three purposes: (1) detect 

infestations, (2) determine or delimit the extent of infestations, and

(3) evaluate the effectiveness of control strategies employed to achieve 

eradication. For the Asian longhorned beetle, surveys have consisted of 

visual inspections of public and private property done from the ground 

or by tree climbers and with bucket trucks. 

• Quarantines: State and APHIS officials established what they term 

“parallel quarantines” where state and APHIS officials met to determine 

the quarantine boundaries and items to be regulated. The state 

established a quarantine allowing state officials to use their authority to 

regulate items that contribute to the spread of the beetle. The federal 

government followed with a federal quarantine to prevent the interstate 

spread of the beetle through the movement of infested wood and wood 

debris. Initial state and federal quarantine boundaries were set, based 

on current research, as small as possible to lessen their impact on 

affected parties but large enough to prevent the spread of the beetle. As 

government officials gained more knowledge about the beetle, a 

protocol was established for establishing and expanding quarantine 

boundaries. Because the initial quarantine boundaries were small, 

government officials expanded the quarantine boundaries to account for 

infestations that were larger than initially identified, in accordance with 

the new protocols. Beginning in 2004, APHIS and state officials have 

been removing quarantines in Illinois and New Jersey as survey results 

of the infested areas over 3 years have shown no signs of the beetle’s 

presence. 

• New York: New York imposed an initial quarantine in December 1996, 

which was followed by a federal quarantine in March 1997, for areas 

in the boroughs in Brooklyn and Queens and a small area in 
Appendix III

Review of Efforts to Control and Eradicate 

the Asian Longhorned Beetle

Page 85 GAO-06-353 Invasive Forest Pests

Amityville on Long Island. APHIS expanded the New York 

quarantines on six other occasions as additional infestations were 

detected. In total, officials quarantined approximately 132 square 

miles of infested area, covering portions of the boroughs of Brooklyn 

and Queens, small areas in Manhattan, and two areas on Long Island.

• Illinois: Illinois established an initial quarantine in July 1998 and 

declared the beetle a nuisance in August 1998.4

 APHIS followed with 

a federal quarantine in November 1998. Illinois expanded the 

quarantine 8 times over the next 6 years to account for additional 

detections of the beetle. Beginning in 2004, APHIS and state officials 

began reducing some quarantine boundaries in light of 3 consecutive 

years of negative surveys in those quarantined areas. In total, officials 

quarantined approximately 35 square miles of infested area.

• New Jersey: New Jersey imposed two quarantines, one in October 

2002 for an area in Jersey City, and one in August 2004 for portions of 

Middlesex and Union Counties. APHIS followed with federal 

quarantines in May 2003 for Hudson County (including Jersey City) 

and in January 2005 for Middlesex and Union Counties. APHIS 

removed the quarantine for Hudson County in October 2005. In total, 

state officials quarantined approximately 20.5 square miles covering 

a small area of Jersey City and Hoboken in Hudson County and parts 

of four smaller cities adjacent to one another in Middlesex and Union 

Counties.

• Public education and outreach: According to APHIS, state, and local 

officials, one of the critical components in detecting and eradicating the 

Asian longhorned beetle was an aggressive program of public education 

and outreach directed at parties directly affected by the quarantines, 

local officials, local plant organizations, and citizens. Several detections 

of the beetle infestations were a result of citizens seeing and reporting 

the pest following a public outreach effort or event. For example, within 

2 hours of a radio show about the beetle, a New Jersey resident called in 

a sighting of the pest, which led to the detection of an infestation.

• Removal of infested trees: Since the beetle has no known natural 

predators in the United States and state and local laws restrict the use of 

4

The date of the declaration is the final date following a public hearing as required by state 

law.
Appendix III

Review of Efforts to Control and Eradicate 

the Asian Longhorned Beetle

Page 86 GAO-06-353 Invasive Forest Pests

insecticides in urban areas, the only way to prevent the spread of the 

beetle has been to cut down, chip, and burn infested trees. Government 

agencies have contracted with private companies to remove and dispose 

of the trees. As of the end of 2004, government officials had removed 

and destroyed over 8,000 infested trees. New York City established a 

free curbside pick-up program to remove residential wood debris within 

the quarantined zones to prevent the spread of the beetle. In Illinois and 

New Jersey, government agencies established disposal sites and wood 

grinders to handle wood debris gathered by both commercial entities 

and residents within the quarantined areas.

• Chemical treatment of noninfested host trees: For trees that are 

susceptible, but not yet infested, APHIS and state agencies have 

contracted with tree companies to treat the trees with an insecticide 

that will kill the beetle in the early stages of its life cycle while it is still 

inside the tree or as an adult feeding on the leaves and twigs. Over 

600,000 noninfested host trees have been chemically treated to kill the 

beetle during its larvae life stage to prevent the beetle from spreading. 

• Replantings: The Forest Service, in cooperation with state and city 

forestry agencies, has provided residents with the option of replacing 

infested trees removed from their properties with a tree species that is 

not a host for the beetle.

• Research: Research to date by government and university scientists has 

focused on the biology and dispersal of the beetle (used to establish 

survey and quarantine boundaries), quality assurance studies of survey 

methods that led to the use of bucket trucks and tree climbers, and the 

development of a trunk injection chemical treatment to augment tree 

removal. Research on lures and traps for the beetle has not yet proven 

successful. Ongoing research into controlling and eradicating methods 

include the following: rearing large numbers of beetles for research 

purposes; effective exclusion technologies to detect and eliminate the 

beetle from foreign cargo entering the country; testing an acoustical 

detection device; a uniform data management system; a system for 

injecting insecticide into the soil to supplement tree trunk injection; and 

alternatives to chemical treatments, such as biological control agents.
Appendix III

Review of Efforts to Control and Eradicate 

the Asian Longhorned Beetle

Page 87 GAO-06-353 Invasive Forest Pests

Status of Asian 

Longhorned Beetle 

Infestation

Starting in 2000, the data indicated a downward trend in the number of 

infested trees identified each year, except for New Jersey where a large 

infestation was detected in 2004. Figure 15 shows the distribution over time 

of the infested trees identified among New York, Illinois, and New Jersey.

Figure 15: Number of Asian Longhorned Beetle-Infested Trees Identified in New 

York, Illinois, and New Jersey

The quarantines in combination with solid management teams and 

aggressive public outreach and education have resulted in the beetle slowly 

being eradicated in the infested states. APHIS and Illinois have removed all 

but one of the Illinois quarantines and plan to remove the last in the spring 

of 2006. APHIS and Illinois state officials expect to complete the 

management program in 2008. APHIS and New Jersey state officials have 

removed the quarantined area in Hudson County and expect to remove the 

other quarantines in the next several years. APHIS and New Jersey officials 

expect to complete the management program in 2011. Although 

0

500

1,000

1,500

2,000

2,500

3,000

Total

New Jersey

Illinois

New York

1996 1997 1998 1999 2000 2001 2002 2003 2004

Source: APHIS.

Number of infested trees

Fiscal year
Appendix III

Review of Efforts to Control and Eradicate 

the Asian Longhorned Beetle

Page 88 GAO-06-353 Invasive Forest Pests

government officials expected complete eradication in New York by 2009, 

that date has been moved to perhaps as late as 2020 due to the detection of 

new, but small infestations; the sheer size of the infestations; the difficulty 

of working in the New York urban environment; and inadequate funding. 

All but one of the government officials involved in the Asian longhorned 

beetle program that we interviewed believed that it will be completely 

eradicated if adequate and consistent funding is provided to complete the 

program.

Funding for Asian 

Longhorned Beetle 

Eradication Efforts

In its initial response to the Asian longhorned beetle detections, APHIS 

drew money from its contingency funds to pay for research and surveys to 

determine the extent of the infestations. Several years into the program, 

APHIS began including part of its funding needs in its appropriations 

requests. APHIS has received $229 million in fiscal years 1996 through 2005 

on the beetle eradication program, using a mix of APHIS contingency 

funds, Commodity Credit Corporation (CCC) transfers, and other 

appropriations. APHIS has estimated that, in total, $578 million will be 

needed to eradicate the beetle. As previously noted, a federal funding 

shortfall in fiscal year 2002 resulted in the cancellation of tree removal and 

insecticide treatment contracts. Because insecticide treatments need to be 

performed for 3 years to be effective, the shortage of funding had a 

significant effect on the treatment schedule. Specifically, it caused APHIS 

and New York state officials to extend the eradication goal in New York 

from 2009 to 2014 or 2020, depending on future funding levels. However, for 

fiscal year 2006, Congress appropriated $20 million for the beetle program, 

an amount that raises doubts about the program’s ability to meet even the 

2020 date, unless USDA uses its emergency authority to transfer funds from 

CCC or other available USDA appropriations. 

As of fiscal year 2006, over $249 million has been provided for the 

eradication of the beetle since it was first detected. Table 2 provides detail 

on federal funding toward eradication of the Asian longhorned beetle.
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Table 2: APHIS Budget Authority for the Asian Longhorned Beetle for Fiscal Years 

1997 through 2006 

Source: APHIS.

a

APHIS funded fiscal years 1997 and 1998 from its contingency fund.

b

APHIS funded fiscal year 2001 from its Miscellaneous Pest fund.

The state of New York has provided over $12 million toward personnel 

costs for state employees devoted to the Asian longhorned beetle 

eradication program, management of tree removal contracts, tree 

replanting, and implementation of state quarantines. New York City 

provided $18 million toward tree replanting, public outreach, and a woody 

debris disposal program for private residents within the quarantined area. 

Additionally, a few municipalities within infested areas have paid for 

services such as traffic control during tree removal.

Dollars in millions

Funding source

Fiscal year

Commodity Credit 

Corporation funds

Emerging plant pests 

appropriations Total

1997a $0.0 $0.8 $0.8

1998a 0.0 1.3 1.3

1999 6.9 0.0 6.9

2000 14.1 2.1 16.2

2001b 49.6 2.1 51.7

2002 14.6 16.9 31.5

2003 7.0 26.2 33.2

2004 12.9 30.0 42.9

2005 14.6 30.0 44.6

2006 0.0 20.0 20.0

Total $119.7 $129.5 $249.2 
Page 90 GAO-06-353 Invasive Forest Pests

Appendix IV

Review of Efforts to Control and Eradicate the 

Emerald Ash Borer ApendxiIV

Our review of the efforts to control and eradicate the emerald ash borer 

includes a discussion of the origin and spread of the infestation in the 

United States and its potential impacts. We also review the roles of federal, 

state, and local government agencies in addressing infestations and 

describe the management structures and methods they have used to 

control and eradicate this forest pest. Finally, we discuss the current status 

of the emerald ash borer infestation and outline the funds spent to date on 

controlling and eradicating the pest.

Origin and Potential 

Impacts of Emerald 

Ash Borer Infestations

Emerald ash borers are metallic green beetles small enough to fit on a 

penny.1

 They are native to China and other countries in eastern Asia. The 

beetle spends most of its life in tunnels it creates in the outer layer—known 

as the cambium—of ash trees. The tunnels cut off the flow of water and 

nutrients through the cambium and eventually kill the tree, usually within 2 

to 4 years. Scientists believe that ash borers arrived in the Detroit 

metropolitan area of southeastern Michigan by the early 1990s in solid 

wood packing material accompanying products shipped from Asia. Ash 

trees had displayed severe decline for several years in Michigan. However, 

observers attributed the mortality to other causes, including a native borer 

and a disease known as “ash yellows.” It was not until June 2002 that 

government and university officials realized that a nonnative insect was the 

cause. 

Armed with information about a new identification in Michigan, Canadian 

officials confirmed in August 2002, that the ash borer was also in Windsor, 

Ontario. The insect was found in Ohio in February 2003, and in Indiana in 

April 2004, but may have been in those states for several years. In 2003, 

small infestations caused by the illegal movement of nursery stock from 

Michigan were also found in Maryland and Virginia. Many of the 

infestations in states other than Michigan were caused by people 

accidentally moving the beetle in infested firewood, logs, or nursery trees. 

In addition, because ash borer populations are able to spread an estimated 

5 to10 miles per year on their own, they are naturally moving into Ohio and 

Canada from southeastern Michigan.

The emerald ash borer is thought to have caused the death of 

approximately 15 million ash trees, primarily in Michigan. There are 16 

1

The emerald ash borer is also known by the scientific name Agrilus planipennis Fairmaire.
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species of ash trees in North America, and all are believed to be vulnerable 

to the borer. According to Forest Service data, there are approximately 850 

million ash trees in Michigan, 279 million in Ohio, and 147 million in 

Indiana, not counting those planted in communities, residential yards, or 

along public rights-of-way. The Forest Service estimates that there are 

approximately 8 billion ash trees in forests across the country.

Ash trees have been widely planted by homeowners and city governments, 

often to replace elm trees lost to Dutch elm disease. APHIS estimated that 

the total value of urban ash trees in the United States was between $20 and 

$60 billion. The Forest Service estimated that if not contained and 

eradicated, the borer could cause approximately $7 billion in additional 

costs to state and local governments, as well as landowners, for removing 

and replacing dead and dying ash trees in urban and suburban areas over 

the next 25 years.2

 In addition to being a popular ornamental tree, ash 

lumber is used to make furniture, tool handles, flooring, and sports 

equipment. USDA estimated that the value of ash timber grown in the 

eastern United States is $25.1 billion. Ash trees also (1) serve an ecological 

role by providing habitat and food for wildlife and (2) provide other 

environmental functions, such as producing oxygen and providing energyconserving shade.

Federal, State, and 

Local Roles in 

Controlling and 

Eradicating the 

Emerald Ash Borer 

• Federal government: As with the Asian longhorned beetle program, 

USDA’s APHIS/PPQ group has the lead for managing the emerald ash 

borer. APHIS surveys for the pest; regulates its movement; and conducts 

control, public awareness, and technology development activities. The 

Forest Service conducts restoration and research, and has assisted with 

surveying. USDA’s Agricultural Research Service has also conducted 

research on the ash borer. 

• State governments: The departments of agriculture in Michigan and 

Ohio and the department of natural resources in Indiana are the state 

agencies managing the emerald ash borer control program at the state 

level. APHIS has entered into cooperative agreements with these 

agencies through which it funds survey, regulatory, control, and public 

awareness activities. 

2

The Forest Service is in the process of refining this estimate.
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• Local governments: Municipal agencies, such as departments of public 

works or forestry, remove dead and dying ash trees from public land. 

This has been a large task primarily in the core-infested area of 

Michigan, where APHIS and the state have not carried out large tree 

removal projects. The Forest Service has funded local governments’ 

replanting efforts to replace ash trees.

Management 

Structures and 

Methods Used to 

Control and Eradicate 

the Emerald Ash Borer

USDA and Michigan, Ohio, and Indiana have formed several organizational 

bodies to address the emerald ash borer problem. In July and August 2002, 

APHIS convened two New Pest Advisory Group teleconferences for the 

emerald ash borer.3

 The advisory group noted that eradicating the beetle 

was not a viable option because it was too widespread. The group also 

noted that a decision to eradicate would only make sense if Canada also 

decided to eradicate. Instead, it recommended taking steps to slow the ash 

borer’s spread while conducting research on management techniques.

In 2002, APHIS formed an emerald ash borer management team to 

implement the control program. The team consists of representatives from 

APHIS; the Forest Service; the departments of agriculture from Michigan, 

Indiana, and Ohio; and universities in the three states. APHIS and the 

Forest Service also developed and cochair a tristate committee made up of 

the state plant pest regulatory officials and state foresters. The primary 

purpose of the committee is to help ensure that state foresters have a “seat 

at the table” and to identify where the state forests can play an active role 

to contain and eradicate the pest.

APHIS also formed a science advisory panel to examine the ash borer’s 

threat in more detail, and to make recommendations to the management 

team.4

 The panel met in October 2002, October 2003, January 2004, 

December 2004, January 2005, and December 2005 and provided 

recommendations to the federal management team after each meeting. 

Throughout this period, the panel has stressed the need for aggressive 

3

The group included representatives from APHIS, the Forest Service, USDA’s Agricultural 

Research Service, the Michigan Department of Agriculture, Michigan State University, the 

National Plant Board, and the Oregon Department of Agriculture. (Oregon was represented 

by an expert on similar beetles.)

4

As of December 2005, the panel consisted of two APHIS employees, one Forest Service 

employee, two university professors, one state employee, three Canadian government 

employees, and one retired Forest Service employee.
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measures to control the pest. For example, in October 2002, the panel 

stated its belief that urgent action was critical if the insect populations 

were to be contained, reduced, and ultimately eradicated with cooperation 

from Canada. The panel also recognized that the effort would be long and 

complicated, requiring substantial commitment for success. The alternative 

would be the potential loss of North American ash as landscape and forest 

trees. 

Additionally, each of the three affected states has formed a task force to 

support state emerald ash borer management programs. The teams 

typically comprise representatives from the state department of 

agriculture, the state department of natural resources, universities, and 

relevant USDA agencies. The state management programs design and carry 

out regulatory and control activities in consultation with USDA. While the 

states have their own authorities to take steps to address the ash borer, 

USDA provides funding for those activities through cooperative 

agreements. These agreements spell out the financial support that USDA is 

to provide and the activities that the states have agreed to conduct. 

Finally, the following methods have been or are being used in efforts to 

control and eradicate the emerald ash borer.

• Overarching strategy: The current goal of the APHIS emerald ash borer 

program is to eradicate the pest in Ohio and Indiana and keep it 

contained within the Lower Peninsula of Michigan. As APHIS and the 

Science Advisory Board learned more about the extent of infestation, 

the government response has evolved to what is known as the “gateway 

approach.” Drawing upon the geography of Michigan, APHIS identified 

three gateways to defend: (1) the boundary between southern Michigan 

and northern Ohio and Indiana; (2) the Straits of Mackinac between the 

Lower and Upper Peninsulas of Michigan; and (3) the St. Clair River 

separating the eastern portion of Michigan and the southwestern 

portion of Ontario, Canada. However, the emerald ash borer has spread 

outside of the Lower Peninsula of Michigan and into each of the three 

gateways, and in some cases beyond. The strategy calls for focused 

attention on the gateways to keep more ash borers from spreading 

beyond them and to push current infestations back toward them. This 

approach is being implemented in a variety of ways, including surveying, 

regulatory enforcement, eradication, and public education. In the 

meantime, the strategy calls for little work—such as surveying or 

eradication—in the core-infested area of southeastern Michigan.
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• Surveys: Following the ash borer’s identification in 2002, the federal and 

state governments have conducted a wide range of detection and 

surveying activities to determine the extent of infestation. The Science 

Advisory Panel recommended that Indiana and Ohio survey in a band 

running 50 miles south of Michigan, while Michigan needed to survey 

throughout the state except for in the 20 southeastern counties already 

known to be infested. APHIS, the Forest Service, and the states use two 

basic techniques to survey for ash borers. Visual surveys consist of 

looking for symptoms of infested trees, including thinning crowns, dead 

branches, cracked bark, new sprouts from the base of the tree, and exit 

holes. Visual surveys were also enhanced by the use of tree climbers or 

bucket trucks to examine tree crowns. Agencies are also visually 

inspecting sites considered to be at high risk of infestation, including 

nurseries, campgrounds, firewood dealers, and sawmills. For example, 

Michigan reported that in 2004, it conducted 1,032 “high-risk” 

inspections of businesses and other entities and surveyed 1,068 public 

and private campgrounds in the Upper Peninsula alone. 

The second method of surveying is to use “trap trees.” Healthy trees are 

girdled, meaning that bark is stripped from a section of the tree trunk. 

The girdling is thought to stress the tree and cause it to emit chemical 

signals that might attract the insect. After a period of time, the tree is cut 

down and debarked to determine whether borers have infested it. The 

Ash Borer Science Advisory Panel recommended varying the density of 

trap trees from 4 per township to as many as 36 per township, with the 

larger number placed in the gateways. Townships vary in size, but 36 

square miles is the norm. Therefore, even the most densely surveyed 

townships may have only 1 trap tree per square mile. In 2005, Michigan 

set 10,500 trap trees, while Indiana and Ohio set 1,500 and 1,400, 

respectively. Other states have also added the emerald ash borer to the 

list of pests that they survey for as part of their APHIS-funded 

Cooperative Agricultural Pest Survey. The Canadian government also 

conducts surveys in Ontario. 

Federal and state officials with whom we spoke do not consider either 

surveying technique to be very effective. For most of the year, the ash 

borer is hidden inside the tree, and exit holes are inconspicuous. 

Furthermore, government agencies are not certain that trap trees 

actually attract ash borers any more than ungirdled ash trees do. A 

major shortcoming of the ash borer program is that scientists have not 

developed a lure for the insect that would help find the leading edge of 

infestation and new outliers.
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• Quarantines: Michigan, Ohio, Indiana, and USDA have imposed a series 

of quarantines over an expanding area in an attempt to stop or reduce 

the artificial movement of the emerald ash borer into new locations. In 

general, the quarantines have regulated ash trees, ash lumber, ash logs, 

and hardwood firewood. Under state quarantines, a person or business 

may move regulated items, such as firewood or trees, inside a 

quarantine area but not outside that area unless the material is certified 

to be uninfested. Federal quarantines regulate the movement of the 

same types of materials across state lines. USDA and state regulatory 

officials are in charge of enforcing the quarantines. This enforcement 

includes identifying businesses, such as nurseries, sawmills, and 

firewood dealers, that handle regulated products. Businesses that want 

to ship regulated products outside of the quarantined area generally 

must first obtain approval, via a certificate or limited permit, from the 

state or federal government. These businesses are subject to regular 

inspections. A major objective of the quarantines is to stop people from 

moving firewood, because residents commonly take firewood to 

summer homes or campsites in uninfested parts of the states. State and 

federal regulatory officials have set up so-called “firewood blitzes” 

during which they check motorists at highway rest stops to make sure 

that they are not carrying firewood in violation of the quarantine. 

Michigan has also assigned inspectors to watch for firewood being 

moved across the Mackinac Bridge to the Upper Peninsula. A major 

element of the quarantines is public education. Stakeholders from all 

three states emphasized the importance of educating the public about 

the dangers of moving firewood, a message that the states have 

publicized using highway billboards, press releases, radio public service 

announcements, and mass mailings. While program officials with whom 

we spoke believed that their efforts have reduced the movement of 

potentially infested material, they concede that it is not possible to 

prevent all such movement, particularly of firewood. They believed that 

firewood is the most likely means by which ash borers will be moved to 

new locations. Quarantines imposed in Michigan, Ohio, and Indiana and 

by USDA are discussed in the following text: 

• Michigan: Michigan issued its first quarantine regulations in July 

2002, regulating the movement of ash-related items in 5 counties in 

the Detroit area. Michigan added a 6th county in October 2002. As 

surveys found that the infestation was more widespread than 

originally believed, Michigan quarantined 7 more counties in August 

2003, and another 7 in December 2004. As it added entire counties to 

the quarantine, the state also added so-called “outlier” locations to 
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the quarantine. These are portions of counties where surveyors have 

found small infestations. As of January 2006, there were 21 entire 

counties and 31 outlier locations under quarantine, with quarantines 

pending in other outlying locations. Additionally, in July 2004, 

Michigan revised its internal quarantine to prohibit the sale and/or 

transportation of ash nursery stock into, within, or out of the state’s 

Lower Peninsula. On May 20, 2005, Michigan issued a regulation 

banning the movement of untreated nonconiferous (hardwood) 

firewood5

 out of the state’s Lower Peninsula—regardless of whether 

the wood came from a quarantined area—and allowing the 

movement of ash logs and ash lumber with bark out of the Lower 

Peninsula only under a compliance agreement with the state 

department of agriculture. 

• Ohio: In September 2003, Ohio issued the first of a series of 

quarantines for ash and related products. As of November 2005, Ohio 

had quarantines in place in portions of 11 counties. Ohio also 

prohibits the movement of regulated materials into the state from 

Michigan. 

• Indiana: In April 2004, Indiana issued the first of a series of 

quarantines for ash and related products. The state began by 

regulating one township in Steuben County. Subsequent amendments 

throughout 2004 and 2005 have added new townships to the list of 

quarantined areas. As of January 2006, Indiana had quarantined 9 

townships in 4 counties.

• USDA: The federal government’s first emerald ash borer quarantine 

took effect on October 8, 2003, and covered 13 Michigan counties. 

USDA stated that federal regulations were necessary to prevent the 

spread of the ash borer to other states. On January 5, 2005, USDA 

amended its federal quarantine, effective December 28, 2004, to add 

areas in Michigan, Indiana, and Ohio, noting that recent surveys had 

revealed infestations outside the 13-county quarantined area in 

Michigan. USDA added more areas in Michigan, Ohio, and Indiana to 

the list of quarantined areas, effective February 25, 2005, and even 

more areas effective October 25, 2005. 

5

Ash is a hardwood. All hardwoods are regulated as a precaution because of the difficulty of 

distinguishing ash firewood from some other species of hardwood, such as oak or maple.
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• Removal of infested or potentially infested trees: The primary method 

for controlling emerald ash borer is to cut, chip, and burn infested or 

potentially infested trees. To date, government agencies have cut 

hundreds of thousands of trees in the three states.6

 However, the 

management team and Science Advisory Panel have agreed that the 

priority for tree removal is in the gateway areas and outlying areas, 

rather than in the core-infested area of southeastern Michigan. 

The Science Advisory Panel currently recommends tree removal 

projects that strive to cut all ash trees within a 0.5 mile radius of a tree 

known to be infested in an outlying area. The highest priorities are 

those outlying areas in or near one of the gateways.7

 However, the 

management program has not been able to complete eradication 

projects in all of the gateway infestations because of inadequate 

funding. As a result, these infestations are likely to continue to pose a 

risk to those gateways. 

Michigan has recently completed or begun removing trees at 3 of the 15 

infested sites in the northern and southern gateway areas. According to 

the state’s program manager, the state will complete the work at these 

sites by May 1, 2006. He also said that the state could have completed 

work at the other 12 sites in the two gateways by May 1, 2006, if 

adequate funds were available. May is a significant target date because 

that is about the time adult ash borers emerge from the trees. To prevent 

their emergence and possible flight to new locations, trees should be 

removed by then. Michigan completed a 0.5-mile eradication in 2005 at 1 

site outside of the gateways; this was a site in the Upper Peninsula 

beyond the northern gateway. As of December 2005, Ohio had 

delineated 11 infested sites but had been able to complete the 0.5-mile 

eradication at only 6 of them. Because of funding shortages, the state 

only planned eradication cuts in 2 counties (Delaware and Auglaize). 

Those infestations were the furthest south from the leading edge of 

6

This is a huge number of trees. However, to put the number in perspective, note that the 

trees include saplings that can be less than 1 inch in diameter.

7

Infested sites slated for eradication are not all equal. To define a site, surveyors map a 1⁄2 

mile radius around a single infested tree. If that is the only infested tree found in the area, 

the eradication zone will be about 8/10 of a square mile. If multiple trees in the area are 

infested, the size of the eradication zone becomes larger. For example, one eradication zone 

in Indiana is about 10 square miles in size. The number of ash trees that need to be cut in 

each area may vary greatly, thereby affecting the time and expense of the eradication 

project. 
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infestation, and the state hoped to complete them by the end of March 

2006. If additional funds are available, the state will focus on the 

furthest east infestations in Erie and Lorain Counties. This would still 

leave numerous infestations in Defiance, Fulton, Hancock, Lucas, 

Ottawa, and Wood counties. As of December 2005, Indiana had been 

able to complete 0.5 mile eradication projects at 2 of the 8 infested sites 

within the southern gateway, according to the State Entomologist. At 

that time, he told us that additional eradication activities were planned 

for 2006.8

 However, on January 25, 2006, the Indiana Department of 

Natural Resources announced that the state will no longer require nor 

fund the removal of trees in an infested area. A department press 

release quoted the State Entomologist as saying “the removal of ash 

trees surrounding an infested area has not proved to be an effective 

approach to controlling the emerald ash borer because of the near 

impossibility in detecting a new infestation.”

While APHIS and Michigan have worked to harvest trees in outlying 

areas, they also created locations where homeowners and local 

governments in the core-infested counties could bring dead ash trees 

for disposal. To help handle the volume of woody debris, by 2004 

Michigan had operations at 8 sites in quarantine areas to grind and 

dispose of ash material. The Michigan Department of Agriculture 

reported that the facilities have disposed of over 300,000 tons of ash. 

The facilities were supported with federal funding, which originally 

enabled the state to offer the service to municipalities and property 

owners at no charge. However, due to funding constraints in 2005, the 7 

sites still in operation began to charge fees that varied depending upon 

the type of material. 

• Research: All of the officials with whom we spoke regarding the emerald 

ash borer noted that government agencies do not have adequate tools 

with which to manage the pest. Over the years since the program began, 

APHIS, the Forest Service, the Agricultural Research Service, and 

universities have conducted approximately 50 research projects to 

support emerald ash borer management. In December 2004, the Science 

Advisory Panel identified several research areas needing continued or 

additional attention, including: (1) survey and detection tools; 

(2) control techniques, including insecticidal control; (3) emerald ash 

8

On January 20, 2006, the department reported the detection of an infestation in Hamilton 

County. The department estimated it had been there for 7 years. 
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borer behavior and biology; (4) host range and host resistance; and

(5) treatment techniques for ash logs and firewood. 

Research on the use of insecticides indicates that there are treatments 

that can be effective at protecting healthy ash trees from being attacked 

by the ash borer. However, these treatments are expensive to apply. 

While it may be feasible for individual landowners to use the treatments 

to protect individual trees, these insecticides cannot be practicably used 

on a large scale in a forest environment and do not appear to have a 

significant benefit for trees already infested. Research on biological 

controls indicates that there may be Asian parasites that could be 

introduced to prey upon emerald ash borer. Stakeholders we spoke with 

believe that successful management of the ash borer will depend upon 

discovery of a biological control that can be used widely and 

inexpensively across the landscape. Typically, it takes many years for 

such technologies to be developed and approved for use.

• Restoration efforts: While little can be done directly to restore forested 

areas affected by the ash borer, the Forest Service has allocated funds to 

help local communities replace trees killed by the pest. For example, in 

2004, Michigan used Forest Service funds to provide more than $855,000 

in grants to communities within the quarantined counties to plant about 

10,700 trees to replace ash trees that had been removed. The state also 

provided 10 grants totaling more than $200,000 to communities located 

in outlier areas to plant more than 3,500 trees. In 2005, the state awarded 

another 80 grants to communities—primarily in the quarantined areas—

to pay for the planting of approximately 13,000 trees. These trees are 

small in size and number in comparison to the dead trees removed. 

Status of Infestation The emerald ash borer now infests an estimated 40,000 square miles in 

three states plus Ontario, Canada. Government surveyors continue to find 

new infestations, including some that scientists estimate began several 

years ago. While program managers believe that quarantines have helped to 

slow the artificial spread of the pest, most do not believe that quarantines 

have completely stopped the public from moving the pest. Movement in 

firewood is a particular concern. In addition, populations of the pest are 

able to naturally spread on their own. Considering these circumstances and 

the lack of cost-effective management tools, program officials with whom 

we spoke were not optimistic that the infestation can be eradicated. In 

December 2005, the ash borer Science Advisory Panel concluded that 
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current resources available to the program are inadequate to achieve the 

long- or short-term goals of the program. 

Funding for Emerald 

Ash Borer Control and 

Eradication Efforts

From fiscal years 2002 through 2006, the federal government has allocated 

about $107 million for the emerald ash borer program. The primary source 

of funding for the emerald ash borer program has been USDA APHIS, 

which has had budget authority of over $93 million from fiscal years 2002 

through 2006 (see table 3). The Forest Service has been the other major 

source of federal funding, with budget authority of close to $19 million 

during that time period (see table 4). The Secretary of Agriculture has 

allocated funds to the program from the emergency CCC and 

congressionally appropriated pest management and forest management 

programs. Funds support work done by the states as well as by federal 

employees assigned to work on the program.

Table 3: APHIS Budget Authority for the Emerald Ash Borer Program, by Funding 

Source and Fiscal Year

Source: APHIS.

Dollars in millions

Fiscal year

Funding source

Commodity Credit 

Corporation funds

Other 

appropriated 

funds Total

2002 $0.0 $0.2 $0.2

2003 14.6 0.0 14.6

2004 43.4 1.5 44.9

2005 18.8 5.0 23.8

2006 0.0 10.0 10.0

Total $76.8 $16.7 $93.5
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Table 4: Forest Service Budget Authority for Emerald Ash Borer Activities, by Funding Source and Fiscal Year 

Source: Forest Service.

APHIS issued a strategic plan in 2005 that projected $383,750,000 would be 

needed from fiscal years 2005 through 2018 to eradicate emerald ash borer. 

Of that total, $162,900,000 would be needed in Michigan, $87,250,000 in 

Ohio, and $31,050,000 in Indiana. However, actual funding levels in fiscal 

years 2005 and 2006 have been considerably lower than what APHIS 

believed was needed—$23.8 and $10.0 million versus $43 and $34 million, 

respectively—raising doubts about those long-term estimates. 

Dollars in millions

Funding source

Fiscal year

Commodity Credit 

Corporation 

appropriations

State and private forestry 

appropriations

Research and 

development 

appropriations Total

2002 $0.00 $0.04 $0.00 $0.04

2003 2.80 0.95 0.70 4.45

2004 0.00 4.59 0.80 5.39

2005 0.00 4.49 1.13 5.62

2006 (anticipated) 0.00 1.90 1.25 3.15

Total $2.80 $11.97 $3.88 $18.65
Page 102 GAO-06-353 Invasive Forest Pests

Appendix V

Review of Efforts to Control and Eradicate

P. ramorum ApendxiV

Our review of the efforts to control and eradicate Phytophthora ramorum

(P. ramorum) includes a discussion of the origin and spread of the 

infestation in the United States and its potential impacts. We also review 

the roles of federal, state, and local government agencies in addressing 

infestations and describe the management structures and methods they 

have used to control and eradicate this plant pathogen. Finally, we discuss 

the current status of the P. ramorum infestation and outline the funds 

spent to date on controlling and eradicating the pathogen.

Origin and Potential 

Impacts of P. ramorum

P. ramorum is a recently introduced plant pathogen of unknown origin 

currently found in natural and nursery environments in North America and 

Europe. It is unclear how the pathogen arrived in the United States. The 

pathogen is the causal agent of the plant disease known as Sudden Oak 

Death and has caused the death of tens of thousands of tanoak and true 

oak trees throughout central coastal California.1 P. ramorum has also 

infected thousands of shrubs and herbaceous plants in natural and nursery 

environments. The pathogen can spread via spores that move through 

water, moist soil, wind-blown rain, and the movement of infected plant 

materials. Moisture seems to be an important factor for the pathogen’s 

survival and spread, and the natural infestation appears along the path of 

the coastal fog belt in California. In addition, detecting infected plants can 

be difficult due to the variability of symptoms by species. The large range 

of hosts and the varying symptoms have added to the difficulty in managing 

P. ramorum.

In the mid-1990s, hikers noticed the apparent sudden death of tanoaks in 

the populated, wildland-urban interface environments of Marin, Santa 

Cruz, and Monterey counties in California. Despite the public reporting of 

observed tree mortalities, no action was taken to determine the cause until 

coast live oaks began to show signs of decline in 1997. By the end of 2001, 

the infestation had spread to 9 California counties and was found on 40 

acres in Curry County, Oregon.2

 Since that time, the pathogen has 

continued to spread in California’s natural environment and now infests 14 

central counties. 

1

The tanoak, Lithocarpus densiflorus, is not a member of the oak genus.

2

According to the Oregon Department of Forestry, there is no evidence of the pathogen 

spreading from California to Oregon.
Appendix V

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Page 103 GAO-06-353 Invasive Forest Pests

The Forest Service constructed a preliminary risk map of the United States 

in 2002, to determine the highest risk natural areas for potential 

P. ramorum infestations on the basis of potential pathways, susceptible 

plant species, and weather conditions favorable to the spread and survival 

of the pathogen. (See fig. 9 in the letter of this report.) The map indicates 

that the Appalachian Mountains and the coastal areas of California, 

Oregon, and Washington are at the greatest risk of possible infestation. The 

map suggests areas of lower risk, based on moisture and temperature, 

among other factors, that may serve as a barrier to P. ramorum’s natural 

spread between the western and eastern United States. The risk map also 

demonstrates the threat posed by the artificial spread of the pathogen to 

the oak forests of the eastern United States. The first detection of the 

pathogen on a nursery plant—a rhododendron—occurred in January 2001, 

in a California nursery surrounded by a heavily P. ramorum-infested forest. 

However, the discovery did not raise much concern within the nursery 

industry or the scientific community in California since the pathogen was 

still perceived to be primarily a threat to the natural landscape. This was 

despite the presence of a different population and mating type of 

P. ramorum infesting European nurseries and garden centers. In March 

2004, the APHIS P. ramorum National Nursery Survey discovered the 

pathogen on camellias in a large nursery in Los Angeles County, California, 

an area considered to be low risk for the spread of P. ramorum. Agency 

officials determined that the nursery had shipped potentially infected 

plants to over 1,200 establishments in 39 states. By the end of 2004, APHIS 

confirmed P. ramorum at 176 sites in 22 states, and over 1 million nursery 

plants were destroyed as a result of the detections. 

The long-term environmental impacts of P. ramorum are not well 

quantified. Government agencies estimate that P. ramorum has killed tens 

of thousands of trees in California and hundreds in Oregon, although the 

true number of mortalities is unknown. The extent of P. ramorum

infestation in the natural environment is oftentimes difficult to determine 

since the distribution of mortality within the landscape is patchy. Also, 

secondary pests often infect P. ramorum-infected trees, making diagnosis 

difficult. However, in some areas, mortality can be as high as 85 percent. 

The Forest Service is conducting an analysis to determine the number of 

tree mortalities, but the results are still pending. Oak species are important 

for forest and woodland biodiversity, and tree mortality resulting from

P. ramorum can lead to the loss of food and habitat for wildlife, increase 

the risk of fire, and cause soil erosion. 
Appendix V

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ramorum 

Page 104 GAO-06-353 Invasive Forest Pests

The economic impacts associated with P. ramorum affect several 

stakeholder groups, including the forest and horticultural industries. The 

oak hardwood forest is the largest forest type in the United States and is an 

important commodity in the timber products industry. The Forest Service 

has estimated the potential threat to commercial timber production could 

potentially exceed $30 billion dollars if P. ramorum were to become 

established in the eastern deciduous forests. California’s timberlands alone 

are valued at over $500 million for forest products. Furthermore, live oaks 

play a more important role in the local ecology as one of the key drought 

tolerant species and are widely prevalent as a landscape tree, adding to 

property values in upscale communities. In addition to the timber industry, 

the potential impact of the pathogen to the U.S. nursery industry is high. 

Since the pathogen was detected in nurseries in 2002, damage to the 

nursery industry has been estimated to be between $3 and $17 million, 

including costs associated with inventory management, green waste 

disposal, and insurance. This estimate does not, however, include lost 

sales. 

Despite affecting an area with a population of more than 7 million people, 

the true social impact of P. ramorum has yet to be determined. Affected 

stakeholders include homeowners, Native American tribe members, 

arborists, and firefighters. For example, the Kashia tribe, currently the only 

Native American tribe with P. ramorum on their lands, has historically 

used the tanoak acorn as one of the main staples in their diet. Tanoak 

acorns and other host plants are also used in ceremonial dress and baskets. 

The sociocultural impact of the loss of tanoak trees on this community is 

difficult to quantify. Likewise, it is equally difficult to quantify the impact of 

the loss of coast live oaks to neighborhoods in which they are a primary 

ornamental species. 

Federal, State, and 

Local Roles in Efforts 

to Control and 

Eradicate P. ramorum

At the federal level, APHIS regulates the interstate movement of host and 

associated host plants and other regulated articles from quarantined areas 

in California and Oregon. In addition to funding inspections in regulated 

states, APHIS has also coordinated inspections at nurseries in states across 

the country. To date, the Forest Service’s primary activities have included 

sponsoring extramural research projects and coordinating surveys of 

forested areas. 

State agriculture departments in California and Oregon regulate the 

intrastate movement of regulated articles, monitor quarantines, and 

undertake eradication efforts that take place within their own state. 
Appendix V

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Page 105 GAO-06-353 Invasive Forest Pests

Through cooperative agreements with APHIS, regulated states also inspect 

nurseries that ship hosts and associated host plants interstate. In 

California, the state agriculture department contracts with the county 

agriculture inspectors to inspect interstate shipments and conduct annual 

nursery inspections. Other state agriculture departments participate in the 

P. ramorum National Nursery Survey by sampling high-risk nurseries in 

their state. In addition, state forestry and natural resource departments 

inspect forests for the National P. ramorum Survey of Forest 

Environments in partnership with the Forest Service. 

In contrast to California’s control program, Oregon is attempting to 

eradicate the pathogen from a small portion of Curry County with 

assistance from the Forest Service. Aerial surveys first detected symptoms 

of the pathogen in July 2001, and subsequent extensive ground surveys of 

the area determined the infestation to be limited to 40 acres within a

9-square mile area. Oregon and the Forest Service established an 

eradication program that clearcut and burned host trees and plants in the 

infested area. As of December 2005, the program had identified 51 infested 

sites in Oregon covering a total of 88 acres and increased the quarantine 

area to 22 square miles in early 2006. 

Efforts to Control and 

Eradicate P. ramorum

• Overarching strategy: Because there is no cure, minimizing the artificial 

spread of P. ramorum is the primary management action in California. 

Based on the widespread natural area currently infested by P. ramorum

along the central California coast, containment of the pathogen through 

quarantine regulation is the only feasible alternative since the current 

level of infestation is too widespread to attempt large eradication 

efforts. However, in areas where the infestation is not considered to be 

widespread, more aggressive, slow-the-spread or eradication efforts can 

be implemented. For example, in addition to the eradication effort in 

Curry County, Oregon, the Forest Service is coordinating a 

slow-the-spread project in Humboldt County, California, where the 

infestation is relatively small. These efforts include early detection and 

monitoring of the area, selectively removing host plants to limit 

pathogen spread, eradicating hot spots, and using various fungicides to 

inhibit sporulation of P. ramorum on tanoaks. For nurseries with 

confirmed positive detections, APHIS’s regulatory protocol is to destroy 

all host and associated plats and plant parts within a specific block area. 

However, this destruction does not ensure eradication and several 

nurseries have had subsequent outbreaks. APHIS is revising the 

protocol in an effort to prevent these reoccurrences. 
Appendix V

Review of Efforts to Control and Eradicate P. 

ramorum 

Page 106 GAO-06-353 Invasive Forest Pests

• Surveys: APHIS and the Forest Service have joined with state agencies 

across the country to survey for P. ramorum in nurseries and forest 

environments. APHIS coordinates the P. ramorum National Nursery 

Surveys with state agriculture departments. The agency’s goal is to 

survey high-risk nurseries in all 50 states to determine whether the 

pathogen has been spread artificially through infected nursery stock. 

Any positive detection of the pathogen in nurseries would trigger further 

investigations to determine the movement of potentially infected plants 

between nurseries and customers. The Forest Service has conducted 

aerial and ground surveys in California and Oregon to identify 

infestations, and is coordinating the National P. ramorum Survey of 

Forest Environments with state forestry agencies to inspect forests near 

nurseries that have received plants from areas that are considered highrisk. 

• Quarantines: Although Oregon and California took action to prevent 

the pathogen’s artificial spread through intra- and interstate quarantines 

and regulations beginning in 2001, the federal government was slower to 

enact regulations. In February 2002, APHIS issued an interim rule 

quarantining 10 counties in California and part of Curry County, Oregon, 

and regulating nurseries that operated within the quarantined counties 

that shipped host or associated host plants or other regulated articles 

outside of the area. At that time, knowledge of the pathogen’s life cycle 

was limited, and it was believed that areas in Southern California would 

be inhospitable due to the dryness and heat. In March 2004, it came as a 

surprise when the P. ramorum National Nursery Survey confirmed 

detections of the pathogen in a Southern California nursery well over 

400 miles from the nearest known infested forest. Shipments from this 

nursery were traced to over 1,200 establishments in 39 states. Within 1 

month, 15 states imposed their own quarantines on nursery products 

and some states banned outright all California nursery stock shipments. 

California nurseries were estimated to have suffered $4.3 million in lost 

sales for March 2004. 

APHIS responded to the positive nursery detections by issuing an 

emergency order extending the quarantine to 2 additional California 

counties on April 9, 2004, requiring all California nurseries shipping host 

and associated articles interstate from nonquarantined counties to be 

visually inspected and tested before shipping occurred. However, after 

meetings with the National Plant Board and the National Association of 

State Departments of Agriculture, APHIS amended the emergency order 

on April 22, 2004, to require California nurseries in the nonquarantined 
Appendix V

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ramorum 

Page 107 GAO-06-353 Invasive Forest Pests

counties that shipped P. ramorum hosts and associated articles 

interstate to be inspected by a regulatory official, sampled, and tested 

for the disease before shipping. 

Despite the federal quarantines and order, some states continued to 

quarantine nursery products from California. Five states requested a 

Special Needs Exemption from the federal regulations in July 2004, but 

APHIS denied those requests.3

 In addition, California and the nursery 

industry requested that APHIS take measures against the states that 

were imposing quarantines more stringent than the federal 

government’s. APHIS, however, did not take action against these states. 

In July 2004, the California Association of Nurseries and Garden Centers 

filed a suit against the Commissioner of the Kentucky Department of 

Agriculture and others claiming the state violated the Supremacy Clause 

of the United States Constitution and the federal Plant Protection Act by 

regulating California nursery stock for P. ramorum in a manner that is 

inconsistent with and exceeds federal regulation. The lawsuit was 

settled the same month and the court entered a consent order under 

which the Kentucky defendants agreed to a permanent injunction 

prohibiting implementation or enforcement of any regulations, orders, 

policies, or quarantines for P. ramorum that are inconsistent with or in 

excess of USDA’s regulation of the pathogen.

Also in July 2004, APHIS conducted a review of its P. ramorum

management program to analyze current USDA policy, the regulatory 

responses, and the status of P. ramorum in the United States. In a 

memorandum to the APHIS Administrator, the PPQ Deputy 

Administrator wrote that while eradication in the natural environment is 

likely not viable because that pathogen is too widespread, quarantine 

regulations should continue. Another outcome was the decision to 

expand the federal order when needed on the basis of each situation’s 

specific risk of spreading P. ramorum in interstate trade. 

After much deliberation with stakeholders, APHIS issued an emergency 

federal order on December 21, 2004, that went into effect on January 10, 

2005, replacing the earlier emergency order. The order—which expires 

in January 2008—requires all nurseries in California, as well as Oregon 

3

Under the Plant Protection Act, a state may not regulate pests more stringently than USDA, 

unless the state has requested and the Secretary of Agriculture has made a finding of 

“special need” based on sound scientific data or a thorough risk assessment.
Appendix V

Review of Efforts to Control and Eradicate P. 

ramorum 

Page 108 GAO-06-353 Invasive Forest Pests

and Washington, that ship host and associated plant nursery stock 

interstate to have their nursery stock inspected, sampled, tested, and 

certified free of P. ramorum. In addition, nurseries in a quarantined area 

that ship nonhost plants interstate must undergo an annual visual 

inspection. APHIS will decide what further actions need to be taken to 

control P. ramorum when the emergency order expires in 2008. 

Status of the 

P. ramorum

Infestation

At this time, there is no known cure for plants infected with P. ramorum. 

Although a number of fungicides are being tested, there is no chemical 

treatment available to eliminate P. ramorum when the pathogen is wellestablished in the natural environment or on nursery stock. Without a cure, 

minimizing the artificial spread of P. ramorum is the primary management 

action. Currently, P. ramorum is known to infect species in more than 55 

plant genera. The complete list of hosts is unknown and continues to grow 

as additional infected species are identified. As of October 2005, the

P. ramorum National Nursery Survey had identified 25 positive detections 

in nurseries in 2005. Changes in the federal order, effective January 2005, 

have increased nursery inspections and by the end of 2005, APHIS found 99 

confirmed positive detections of P. ramorum associated with nursery 

plants in 7 states, a decline from 2004. Key stakeholders with whom we 

spoke do not believe the pathogen can be eradicated from the natural 

environment in California. However, the infestation in Oregon has been 

contained to a small portion of Curry County, and many of the stakeholders 

with whom we spoke are optimistic about controlling and eventually 

eradicating its spread in Oregon and the nursery environment.

Funding of Efforts to 

Control and Eradicate 

P. ramorum

Several federal and state agencies contribute funding and resources to the 

P. ramorum program. APHIS provides funding in the form of annual 

cooperative agreements to regulated states for management activities, such 

as inspecting, sampling, and testing nursery plants. The Forest Service has 

provided infrastructure support and funding to the California Oak Mortality 

Task Force4

 for public outreach since 2000. The agency has also provided 

funds to Oregon for eradication activities in Curry County. Additional 

contributions to P. ramorum management by other USDA agencies, such 

4

The California Oak Mortality Task Force is a coalition of research and educational 

institutions, public agencies, nonprofit organizations, and private interests. Its stated 

objectives include assisting communities affected and threatened by P. ramorum and 

providing information and education to interested parties. 
Appendix V

Review of Efforts to Control and Eradicate P. 

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Page 109 GAO-06-353 Invasive Forest Pests

as the Agricultural Research Service and the Cooperative State Research, 

Education, and Extension Service, include providing training and 

educational materials to diagnose infected plants in the landscape 

environment, improving diagnostics, and developing fungicides. Table 5 

outlines the funds spent by various USDA agencies to control P. ramorum

between fiscal years 2000 and 2005.

Table 5: Summary of USDA funding for P. ramorum, Fiscal Years 2000 Through 2005

Source: USDA. 

Dollars in millions

Fiscal year

Funding, by USDA agency

Forest Service

Animal and Plant Health 

Inspection Service

Agricultural 

Research Service

Cooperative State 

Research, Education, 

and Extension Service Total

2000 $0.12 $0.00 $0.00 $0.00 $0.12

2001 4.20 0.00 0.00 0.00 4.20

2002 0.97 0.90 0.00 0.00 1.87

2003 3.70 2.00 0.62 0.30 6.62

2004 3.70 19.50 1.30 0.30 24.80

2005 4.40 12.40 1.00 0.12 17.92

Total $17.09 $34.8 $2.92 $0.72 $55.53
Page 110 GAO-06-353 Invasive Forest Pests

Appendix VI

Risk Analysis as a Tool to Address Invasive 

Forest Pests ApendxiVI

The PPQ organization within APHIS is the primary federal agency 

responsible for protection of the nation’s public and private forests from 

invasive forest pests, while providing for movement of agriculture and 

other commodities across the United States and its borders. In 1999, 

President Clinton signed Executive Order 13112 on invasive species. The 

order established the National Invasive Species Council, in part, to 

coordinate the federal government’s efforts to manage risks associated 

with invasive pests. The order also called for a scientific process to 

evaluate risks associated with the introduction and spread of invasive pests 

and to develop a risk-based process for control and management of 

invasive pests. Furthermore, under the World Trade Organization’s 

Agreement on the Application of Sanitary and Phytosanitary Measures 

(SPS), the United States must be able to justify protection measures against 

invasive pests on the basis of scientific principles and a risk assessment 

and protection measures must not be applied in a manner that would 

constitute a disguised restriction on international trade. Consequently, risk 

analysis is important as it constitutes key evidence for member countries 

demonstrating that the measures they have adopted are to ensure human, 

animal, or plant protection, rather than to create arbitrary barriers to trade. 

To this end, APHIS develops and employs risk analysis as an essential tool 

in meeting its responsibilities for detection, control, as well as development 

of appropriate programs aimed at management of invasive pests.

Although PPQ is the primary agency that assesses the risks that invasive 

plant pests pose to the United States’ economy and environment, a large 

number of offices within USDA and APHIS are engaged in activities related 

to risk analysis. The Center for Plant Health Science and Technology 

(CPHST), in particular the Plant Epidemiology and Risk Analysis 

Laboratory group in the CPHST division of PPQ, is the scientific support 

organization that assesses the risks that invasive plant pests pose to the 

United States’ economy. Risk Analysis Systems, a component of the Policy 

and Program Development (PPD) office within APHIS is devoted to basic 

investigations associated with risk analysis, data collection, quantitative 

methods, and other analytical support activities required for APHIS 

programs. The office of Policy Analysis and Development, also in PPD, 

provides economic analysis for rulemaking and cost-benefit analysis 

required for a USDA “major proposed regulation,” the primary purpose of 

which is to regulate issues of human health, human safety, or the
Appendix VI

Risk Analysis as a Tool to Address Invasive 

Forest Pests

Page 111 GAO-06-353 Invasive Forest Pests

environment.1 Finally, the Office of Risk Assessment and Cost-Benefit 

Analysis, under the office of USDA’s Chief Economist, is to ensure that 

regulatory analyses include a risk assessment and cost-benefit analysis that 

are performed consistently and use reasonably obtained and sound 

scientific, economic, technical, and other data. 

In this appendix, we briefly give an overview of APHIS’s responsibility for 

conducting risk analysis for detection, control, and regulation of invasive 

forest pests. We also define the essential component of risk analysis—risk 

assessment and risk management. Finally, we discuss what risk assessment 

was done by APHIS for the three pests investigated in this report.

Pest Risk Assessment 

Is an Essential Element 

of Risk Analysis

Pest risk assessment is the essential first component of risk analysis; risk 

management and communication are the other components. In general, 

pest risk assessment involves estimating the likelihood of the introduction, 

establishment, and spread of invasive pests. Risk assessment also involves 

estimation of economic and environmental consequences associated with 

the spread and establishment of invasive pests. Risk management, 

however, involves identification and selection of appropriate risk 

management options; risk communication involves documentation and 

conveyance of this information to interested parties. 

In general, the protocol and terminology used by APHIS in conducting its 

risk assessments are developed pursuant to the international standards as 

established by the SPS and the International Plant Protection Convention 

(IPPC). Although SPS establishes the baseline requirement for the use of 

risk assessments, IPPC is the key organization for providing the detailed 

guidelines to be followed by member countries when conducting these 

assessments. IPPC guidelines are published by the Secretariat under a 

number of International Standards for Phytosanitary Measures (ISPM)—

such as ISPM No. 11, which provides detailed guidance for risk analysis for 

quarantine pests.2

 Under this standard, the process for risk assessment for 

quarantine pests involves a number of specific steps that could include,

1

A “major regulation” is any regulation that the Secretary of Agriculture estimates is likely to 

have an annual economic impact on the U.S. economy of $100 million in 1994 dollars.

2

IPPC defines a “quarantine pest” as a pest of potential economic importance to the area the 

pest endangers but not yet present there, or present but not widely distributed and being 

officially controlled.
Appendix VI

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Forest Pests

Page 112 GAO-06-353 Invasive Forest Pests

(1) identification of the pest or pathway risk for introduction of the pest, 

(2) estimation of the likelihood of pest entry, (3) estimation of the 

likelihood for establishment and spread, (4) estimation of economic and 

environmental consequences, and (5) integrating this and other 

information about risks into an overall conclusion about risk that will be 

useful to decision makers. 

Resources and data permitting, pest risk assessments can be conducted 

quantitatively where various likelihoods are quantified and integrated. 

Individual risk factors are combined, resulting in an overall conclusion 

about the pest risk. That is, the threat of establishment of the invasive pest 

and the economic and environmental impacts of the pest invasion. 

However, when data for quantitative evaluation are lacking, risk 

assessments are based on a more subjective assignment of the risk values 

and on qualitative scales, such as high, medium, or low risks. Such 

qualitative presentations usually omit the details that are included in the 

more rigorous quantitative risk assessments.3

 

In general, in the absence of reliable data, APHIS relies, to a great extent, 

on qualitative analysis to assess the threat of invasive pests.4

 For example, 

APHIS used a qualitative assessment to assess the risk for entry, 

establishment, and consequence of establishment of the Asian longhorned 

beetle associated with solid wood packing material imported from China. 

Three risk factors—entry, establishment, and consequences—were all 

rated “high.” APHIS then combined these individual risk factors to arrive at 

one overall high-risk rating for the pest. 

3

A more rigorous analysis could, for example, assign ranges and probability distributions to 

introduction, rate of spread, or effectiveness of controls being applied to invasive pests and 

using probability models make projections as to what might happen.

4

The study, Economic and Policy Implications of Wind-Borne Entry of Asian Soybean 

Rust into the United States, is one example of a more rigorous analysis of invasive pests. It 

was conducted by the Economic Research Service in collaboration with other USDA offices. 

The study which was completed in 2004, explicitly introduces probabilities to quantify the 

likelihood of various occurrences and specifies various geographic scenarios of rust 

outbreak extent and yield loss to estimate a range of economic impacts on agriculture 

producers and consumers. 
Appendix VI

Risk Analysis as a Tool to Address Invasive 

Forest Pests

Page 113 GAO-06-353 Invasive Forest Pests

Risk Assessment Is a 

Tool for Risk 

Management

The ultimate value of risk assessment is the extent to which it is used by 

risk managers to target activities, allocate resources, justify regulations, 

and improve the quality of their management decisions. In particular, risk 

assessment can be used to prioritize pest threats, targeting limited 

resources commensurate with the risk of pest threats, and to mitigation 

and control programs that most effectively address the most significant 

threats and produce the most impact for the resources invested. APHIS 

conducts risk assessments to be used for import and export and for 

emergency and regulatory programs. It also could integrate risk-based 

information in several aspects of its invasive pest management decision 

making. 

APHIS conducts risk assessments to assess the potential threat of 

introducing new and of exotic plant pests into the United States when 

permits are requested for importation of plants or plant products.5

 Such 

risk assessment begins by determining the likelihood of a harmful pest 

becoming established in the United States and the magnitude of potential 

adverse consequences. When this risk is deemed unacceptable, the 

assessment could lead to identifying risk mitigation options and eventually 

to decisions to authorize, prohibit, or allow importation under specific 

conditions, depending on the risk and potential adverse effects of the pest. 

Furthermore, for invasive pests that have previously entered the United 

States, risk assessments can be conducted to estimate the likelihood and 

potential damage of further spread across the country and to support 

decision makers’ allocation of resources to different control and 

eradication measures. 

Risk assessment can also become a component of economic analysis 

required for rulemaking to regulate invasive pests. The Policy Analysis and 

Development office provides economic impact and cost-benefit analysis. 

When available, risk assessment can be used as an additional input for 

conducting regulatory impact analysis and is a component of information 

forwarded to decision makers, along with economic analysis.

5

More specifically, risk assessment associated with trade includes commodity risk 

assessment for plants and plant products proposed for import; pathway risk assessment 

associated with baggage, packing materials, and mail; and export risk assessment to support 

market access for the United States exports. 
Appendix VI

Risk Analysis as a Tool to Address Invasive 

Forest Pests

Page 114 GAO-06-353 Invasive Forest Pests

Finally, risk assessment can be a valuable tool used by decision makers in 

budget development, resource allocation, and prioritization programs and 

strategies to control the threat of invasive pests. 

APHIS Has Conducted 

Risk Assessments for 

P. ramorum and the 

Asian Longhorned 

Beetle

The risk assessments for the pests we reviewed were focused on showing 

that the pest problem is potentially significant and warrants a management 

response. We did not see analysis of the costs and benefits of taking 

specific management actions within specific time frames. 

The risk analysis for the pathogen P. ramorum was conducted and 

published in May 2005 by APHIS’s Plant Epidemiology and Risk Analysis 

Laboratory. The analysis was aimed at assessing the risk associated with 

the importation and domestic spread of the pathogen. Such risk 

assessment would make possible the promulgation of regulations and 

present mitigation measures to prevent the movement and spread of the 

pest to noninfested areas of the United States. The assessment was 

conducted pursuant to relevant international standards published by IPPC 

and APHIS guidelines for pest risk assessments.6

In this risk analysis, a qualitative scale was used to rate all individual risk 

factors for P. ramorum. This led to an overall pest risk potential for this 

pest—to spread, infect, and cause potential economic and environmental 

consequences—of a “high” rating. In particular, as there are many areas in 

the United States with potential hosts and climates favorable to the pest, 

the rating for the Host-Climate Interaction Factor was judged to be “high.” 

Similarly, given that many host plants are susceptible to infection by this 

pest, and that a number of other factors, both natural and human-assisted, 

can aid the dispersal of the pest to areas with suitable hosts and climate 

conditions, the risk rating for Host Range and Dispersal Potential factors 

were judged to be “high.” As a result of a “high-” risk rating in these and 

other risk elements, the overall risk potential for the pest was assessed as 

“high.” 

APHIS has not published similar detailed risk assessment studies for the 

emerald ash borer or the Asian longhorned beetle. However, in 1998, 

APHIS published a risk assessment report for the Asian longhorned beetle, 

as a part of a study examining the risks associated with solid wood packing 

6

USDA, APHIS, PPQ, Permits and Risk Assessment Commodity Risk Analysis Branch, 

Guidelines for Pathway-Initiated Pest Risk Assessments, Version 5.02 (October 2000).
Appendix VI

Risk Analysis as a Tool to Address Invasive 

Forest Pests

Page 115 GAO-06-353 Invasive Forest Pests

material imported from China into the United States. According to this 

study, because of widespread detection of the pest in the United States, 

favorable climate, and a wide variety of hardwood tree hosts, both the risk 

of entry through this pathway and establishment of the Asian longhorned 

beetle in the United States were rated as “high.” Furthermore, because 

many studies had suggested that the beetle could severely affect the forest 

resources and forest-related industries in the United States, the risk for 

potential consequences was also rated “high,” leading to a “high” overall 

risk potential for infection from the Asian longhorned beetle in the United 

States. 

Finally, APHIS has not conducted an economic risk assessment for the 

emerald ash borer. The Forest Service generated some preliminary 

estimates of the damages that the ash borer could cause across the country, 

including the impacts on the ash timber industry and ash trees in 

residential areas. APHIS cited these estimates in support of its decision to 

impose quarantine regulations. The Forest Service is in the process of 

revising its analysis of the potential impact of ash mortality in urban areas; 

it expects to complete this analysis in early 2006. 
Page 116 GAO-06-353 Invasive Forest Pests

Appendix VII

Comments from the Department of 

Agriculture ApendxiVI
Appendix VII

Comments from the Department of 

Agriculture

Page 117 GAO-06-353 Invasive Forest Pests
Page 118 GAO-06-353 Invasive Forest Pests

Appendix VIII

GAO Contact and Staff Acknowledgments ApendxiVI

GAO Contact Robin Nazzaro, (202) 512-3841

Staff 

Acknowledgments

In addition to the individual named above, Trish McClure, Assistant 

Director; Ross Campbell; John Delicath; Dewi Djunaidy; Les Mahagan; 

Mehrzad Nadji; Jena Sinkfield; and Amy Webbink made major 

contributions to this report. Important contributions were also made by 

Laura Gatz; Gerry Laudermilk; Charlotte Moore; Judy Pagano; and Jay 

Scott.

(360583)
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