### United States Department of Agriculture

Animal and Plant Health Inspection Service

Plant Protection and Quarantine

Agency Contact Plant Epidemiol ogy and Risk Analysis Laboratory Center for Plant Health Science and Technology
United States Depart ment of Agriculture Animal and Plant Heal th Inspection Service Plant Protection and Quarantine 1730 Varsity Drive, Suite 300 Raleigh, NC 27606 

# Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable CommoditiesThe U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, age, disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual ori entation, genetic information, political beliefs, reprisal, or because all or part of any individual’s income is derived from any public assistance program. (Not all prohibited bases apply to all programs). Persons with disabilities w ho require alternative means for communication of program information (Braille, large print, audiotape, etc. ) should contact USDA’s TARGET Center at (202) 720-2600 (voice and TDD). To file a complaint of discrimi nation, write to USDA, Director, Office of Civil Rights, 1400 Independence Avenue, SW., Washington, DC 20250-9410, or call (800) 795-3272 (voice) or (202) 720-6382 (TDD). USDA is an equal opportunity provider and employer.
The opinions expressed by individuals in this report do not necessarily represent the policies of the U.S. Department of Agriculture.

First Edition Issued 201208/2012-01 Guidelines for Plant Pest Risk Assessmentof Imported Fruit & Vegetable Commodities TOC-1 

# Contents

Section TOC: Conten ts ................

.................... .................... TOC-1

Section TOC: List of Proce dures .................

....................... TOC-3

Section 1: Introduction & Fr amework..............

....................... 1-1

Introduction ........................................................................................... 1-1 Pest Risk Analysis Framework ............................................................ 1-2 Stages of pest risk analysis ................................................................... 1-2 

### The Legal Framework for PRA ........................................................... 1-4 International guidelines fo r considering economic impacts in PRA .. 1-10 National legislative framework for PRA ............................................ 1-14 Climate change in PRA ............ .......................................................... 1-17 

### Overview of the PPQ Risk Assessm ent Model for Commodity Imports for Consumption ........................................................................... 1-18 Overview of the model ....................................................................... 1-18 Volume of consignments consideration .............................................. 1-20 Pathway consideratio ns ...................................................................... 1-20 The endangered area ........................................................................... 1-22 Likelihood of introduction ........ .......................................................... 1-22 Potential consequences of introduction .............................................. 1-22 Uncertainty analysis ............................................................................ 1-23 Overall risk rating ............................................................................... 1-24 Risk mitigation documentation . .......................................................... 1-25 Summary of processes

....................... ...................... ................... ........ 1-25


## Section 2: Conducting Pest Risk Assessment in PPQ ............. 2-1 Stage 1: Initia tion .................................................................................. 2-1 Process 1: Documenting the initiatin g event and scop e ............. .......... 2-2 Process 2: Determining if a weed risk assessment for the commodity is needed ............................................................................................ 2-4 Process 3: Defining the pathway

.................... ....................... ............... 2-6 Process 4: Creating the pest list and pest categorizatio n ...................... 2-9 

### Stage 2: Pest Risk Assessment ........................................................... 2-20 Processes in PPQ commodity import risk assessment

................ ........ 2-20Contents

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### Risk elements evaluated in PPQ commodity import risk assessment .2-20 Process 5: Collecting information and de fining the endangered area .2-22 Process 6: Assessing uncertainty for risk el ements ............. ................2-33 Process 7: Assessing the likelihood of introduction ............ ................2-35 Process 8: Assessing pote ntial consequences of introduction .............2-50 Process 9: Summarizing the final riskratings and uncertainty ...........2-63 

### Stage 3: Risk Man agement ................................................................. 2-64 Risk Management in pest risk analysis ...............................................2-64 Uncertainty in risk management .........................................................2-66 Process 10: Risk mitigation notes

..................... ...................... ............2-67


## Section 3: Supplements and References ....

................. .............. 3-1 Supplement 1: WTO Di sputes ............................................................. 3-1 Supplement 2: Plant Hardiness Zones Area and Population Analysis .. 3-8 Supplement 3: Host Status ................................................................. 3-10 Host status issues in PRAs ..................................................................3-10 Scope and purpose ...............................................................................3-10 Key issues ............................................................................................3-11 Terminology ........................................................................................3-12 Evidence and information sources ......................................................3-16 Interpreting evidence to determine host status ....................................3-19 Background .........................................................................................3-19 Relationship of host status to risk .......................................................3-23 Examples, exceptions, and uncertain ty ...............................................3-24 Appendix A: Recommendation for Prunus persica varieties to be considered non-hosts for Bactrocera cucurbitae ....................................3-27 

### Supplement 4: Evaluation of Evidence ............................................. 3-29
Literature Cited .................................................................................. 3-3308/2012-01 Guidelines for Plant Pest Risk Assessmentof Imported Fruit & Vegetable Commodities TOC-3 

# List of Procedures

Procedure 1-1. Determining if a new or revised risk assessment is needed 2-2
Procedure 1-2. Documenting the initiating event ........................................ 2-3
Procedure 2-1. Determining if a weed risk assessment for the commodity is needed ............................................................................................... 2-4
Procedure 3-1. Defining the path way .......................................................... 2-7
Procedure 4-1. Identifying potential pests for the pest list ........................ 2-11
Procedure 4-2. Optional: Determining whether a pest is actionable ......... 2-12
Procedure 4-3. Determining whether to include anactionable pest on the list . 2-13
Procedure 4-4. Completing the pest list table ........................................... 2-15
Procedure 4-5. Handling organisms identified only to genus level .......... 2-18
Procedure 5-1. Determining the order of analysis ..................................... 2-28
Procedure 5-2. Defining the endange red area ........................................... 2-29
Procedure 6-1. Assessing uncertainty for each risk element ..................... 2-34
Procedure 7-1. Assessing the likeli hood of entry (Risk Element A) ........ 2-36
Procedure 7-2. Determining the likelihood of es tablishment (Risk Element B) 2-42
Procedure 7-3. Determining the combined likel ihood of establishment ... 2-47
Procedure 7-4. Determining the overall li kelihood of introduction .......... 2-49
Procedure 8-1. Determining the potential directimpacts (Risk Element C) . 2- 52
Procedure 8-2. Determining if the pest is like ly to cause unacceptable direct economic impact s ........................................................................... 2-58
Procedure 8-3. Additional analysis for pests wi th undetermined trade impact . 2-59
Procedure 8-4. Determining potential trade impacts ................................. 2-60
Procedure 9-1. Summarizing the final risk ratings and uncertainty .......... 2-6308/2012-1 Guidelines for Plant Pest Risk Assessmentof Imported Fruit & Vegetable Commodities 1-1 

### Section



# 1 Introduction & Framework

Introduction In this document, we provide guidan ce for conducting commodity pest risk assessments in the United States Department of Agriculture (USDA), Animal and Plant Health Inspection Service (APH IS), Plant Protection and Quarantine (PPQ). The purpose of commodity pest risk assessment is to determine
1. the plant pest risk associated wi th fruit and vegetable commodities imported into the United States for consumption and 2. the phytosanitary measures that may be used to mitigate the risk. Risk assessments are conducted by PPQunder the regulatory authority provided in Title IV

— 

### Plant Protection Act of 2000 (7 U.S.C. § 7701-7786, 2000) and in conformity with PPQ’s re sponsibilities as the national plant protection organization (NPPO) for the Un ited States under Article IV.2.f of the International Plant Protection Convention (IPPC).
Pest risk analysis (PRA) is the pr ocess used by NPPOs as the technical justification for phytosanitary measures. PRA is defined by the IPPC as “the process of evaluating biological or othe r scientific and economic evidence to determine whether a pest should be regulated and the strength of any phytosanitary measures to be taken agai nst it.” The process requires a risk assessment to characterize the risk and risk management to determine appropriate measures.
In this document, we provide guidelin es for PPQ risk analysts conducting commodity import pest risk assessments, as well as for stakeholders and trading partners interested in understanding our methodology and rationale. The process we describe here is used to inform risk management, but does not include the risk management analysis.
This document supersedes Guidelines for Pathway-Initiated Pest Risk Assessments, Version 5.02 (PPQ, 2000). Information covered here includes
 an overview of pest risk an alysis as outlined by the IPPC,  the legal framework for conducting pest risk analysis, and  specific guidelines for conducti ng commodity import pest risk assessments for APHIS-PPQ.Introduction & Framework Pest Risk Analysis Framework

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### These Guidelines are based on a qua litative methodology for assessing the likelihood and consequences of pest introduction and spread. Conclusions are expressed as relative rankings based on scientific, technical, and operational evidence and uncertainty. Basic info rmation required by the USDA for initiating the process is found in th e Prerequisite Rule (7 CFR § 319.5, Requirements for submitting requests to change the regulations ).

These Guidelines wi ll be updated as needed to incorporate corrections and improvements. All changes will be logged in Supplement No. 5.


# Pest Risk Analysis Framework Pest risk analysis (PRA) is “the process of evaluating biological or other scientific and economic evidence to dete rmine whether an organism is a pest, whether it should be regulated, and the strength of any phytosanitary measures to be taken against it” (IPPC, 2012).
PPQ’s risk assessment procedures ar e consistent with the International Standards for Phytosanitary Measures (ISPMs) adopted by IPPC as follows:  No. 1, Phytosanitary principles for the protection of plants and the application of phytosanitary me asures in international trade  No. 2, Framework for pest risk analysis  No. 11, Pest risk analysis for quarantine pests including analysis of environmental risks and living modified organisms , and supplements
The use of biological and phytosanitary te rms in these guidelines conforms to ISPM No. 5, Glossary of Phytosanitary Terms (IPPC, 2012). We discuss these standards in more detail in the IPPC St andards related to risk analysis section.


## Stages of pest risk analysis The IPPC describes three stages of pest risk analysis in ISPMs No. 2 and 11: initiation, risk assessment , and risk management.

Initiation 

### The first stage of pest risk analysis, initiation, involves de fining the hazards by identifying the pest(s) and conditions that are of concern and should be considered for risk analysis.
Initiation points include:  Identification of pathway(s). A pathway, often an imported commodity, is identified as a means for the introduction and/or spread of pests. A pathway other than commodity import co uld be identified (natural spread, packing material, mail, garbage, compost, passenger baggage, etc.).Introduction & Framework Pest Risk Analysis Framework

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###  Identification of pests. A specific pest require s evaluation. For example, this may be the result of a pest det ection or interception, because a pest is being imported (e.g., biocontrol organism), because the organism previously was not known to be a pest , or because there was a change in the status or incidence of a pest in the PRA area. The results of initiation are clearly identified hazards (pes ts, pathways, or conditions), which become the focus for risk assessment.  Review of policies. Regulatory policies or operations require evaluation, for example, to revise regulations or requirements; to prioritize risk management activities; if a new sy stem, process, or procedure is introduced; if new information is ma de available that could influence a previous decision; or if an in ternational dispute on phytosanitary measures arises.

Pest risk assessment 

### Stage 2 of pest risk analysis is pestrisk assessment: the evaluation of the probability of the introduction and spreadof a pest and the magnitude of the associated potential economic consequences (IPPC, 2012).
Risk assessment begins by first determining which pests to assess and then evaluating these pests for the likelihood and consequences of their introduction and/or spread. Risk assessment is composed of two distinct phases:
 Pest categorization. A preliminary screening of individual pests to determine whether or not the pest s meet the defining criteria for a quarantine pest or regul ated non-quarantine pest.  Risk assessment . The examination and analysis of biological and economic information toestimate the potential for introduction and spread and the potential eco nomic impact of the pests
Pest risk management 

### Stage 3, pest risk management, is the evaluation and selection of options to reduce the risk of the introduction and sp read of a pest (I PPC, 2012). It results in a summary of options, including re commendations for the selection of preferred options. Options are assesse d based on information about their efficacy, feasibility, and impacts.
The procedure in this stage is to identi fy and evaluate miti gation measures that may be used to reduce the risk. These may be existing measures or measures developed specificallyfor the conditions under consideration.Introduction & Framework The Legal Framework for PRA

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# The Legal Framework for PRA In this section of the gui delines, we provide an overview of the international and national legal framework for pest ri sk analysis. This framework provides the basis for why and how we conduct pest risk analysis, and creates a system of accountability for the c onduct of pest risk analys is. In this section, we address
 The World Trade Organization and the IPPC
,  Relationship of the IPPC to the SPS
,  IPPC Standards related to risk analysis
,  The appropriate level of protecti on and the acceptabl e level of risk
,  Provisional and em ergency measures ,  Precaution under the IPPC and SPS
,  Rational relationship
,  Probable versus possible
,  International guidelines for considering economic impacts in PRA  National legislative framework for PRA
,  Climate change in PRA , and  Relationship of the PPA to the WTO-IPPC framework

.Introduction & Framework The Legal Framework for PRA

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### The World Trade Organization and the IPPC 

### The World Trade Organization (WTO) is the international organization responsible for establishing rules of trad e. The rules are legally binding for its member nations. WTO agreements are th e result of negotiations between WTO Members. Agreements are implemented by Members toward the objective of a non-discriminatory trading system base d on agreed rights and obligations. Each Member can expect that its exports will be treated fairly and consistently in other Member countries and each Member country agrees to do the same for imports into its own country. The WTO Agreement on the Application of Sanitary and Phytosanitary Measures (the SPS Agreement; SPS WTO, 1995) covers requirements for food safety and the life and health of animals and plants. The SPS Agreement requires that re strictions be based on international standards or scientific prin ciples and evidence, that th ey be applied only to the extent necessary to protect health, and that they do not arbitrarily or unjustifiably discriminate between co untries where identical or similar conditions prevail. To achieve its obj ective, the SPS Agreement encourages Members to use international standards, guidelines, and recommendations where they exist, and identifies standard-setting bodies for food safety, animal health, and plant health. Members may adopt SPS measures that result in higher levels of health protection—or m easures for health concerns for which international standards do not exist—provided that they are technically justified. Technical justification is a ccomplished by an assessment of risk taking into account scientific principles and evidence (technically justified). Article 2 of the SPS Agreement (Basic Rights and Obligations ) and Article 5 ( Assessment of Risk and Determination of the Appr opriate Level of Sanitary or Phytosanitary Protection ) describe the central concepts. The IPPC is a multilateral treaty for international cooperation in plant protection, and is identified in the SPS Agreement as th e standard-setting body for plant health. The Convention makes provisions for the application of measures by governments to protect their plant resour ces from harmful pests (phytosanitary measures) that may be introduced through international trade. The IPPC complements the SPS Agreement by providing the international standards recognized by the WTO to ensu re that phytosan itary measures have a scientific basis for their placement and strength and are not used as unjustified barriers to international trade.
Article 5.1 of the SPS Agreement states that WTO Members “shall” ensure that phytosanitary measures are based on an assessment of risk. The agreement defines risk assessment as “The ev aluation of the likelihood of entry, establishment or spread of a pest or disease within th e territory of an importing Member according to the sanitary or phytosanitary m easures which might be applied, and of the associated potentialbiological and economic consequences; or the evaluation of the potential adverse effects on human or animal health arising from the presence of additives, contaminants, toxins, or disease-causing organisms in food, beverages or feedstuffs.”Introduction & Framework The Legal Framework for PRA

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### Slightly different terminology is usedin the IPPC (1997) and associated standards (e.g., ISPMs No. 2, 5, 11, and 21) to reflect the same concepts and obligations. Two terms that are particul arly important are found in Article II ( Use of terms ):
 Technically justified. Justified on the basis of conclusions reached by using an appropriate pest risk anal ysis or, where applicable, another comparable examination and eval uation of available scientific information.  Pest risk analysis. The process of evaluating bi ological or other scientific and economic evidence to determine whether an organism is a pest, whether it should be regulated, and the strength of any phytosanitary measures to be taken against it (IPPC, 2012).

Despite the subtle differences in terminology, the SPS Agreement and the IPPC are clear that a systematic process for gathering, evaluating, and documenting scientific and other information is required to provide the basis for phytosanitary measures affecting tr ade. This involves consideration of economic as well as biological aspects of pest risk for plant health and life.
Relationship of the IPPC to the SPS 

### These requirements of the SPS Agreement create a direct relationship between risk assessment and international st andards, which are established by the relevant international organizations. Th e SPS Agreement states that a risk assessment is not required where me asures are based on international standards. This is because the risk basis for the standard is already internationally agreed upon. Where st andards do not exist or are deemed inappropriate, risk assessment is need ed to provide the justification for measures. Another part of the relations hip involves the standards developed for performing risk assessment. In both cases , the standard setting organizations play a significant role inproviding governments with th e means to justify their SPS measures.
At this time, only a few sp ecific phytosanitary standards can be used to directly support national measures in lieu of risk assessment. Therefore, where phytosanitary measures are concerned, WTO Member governments are largely forced to base their decisions on risk a ssessments. This means that the process used for phytosanitary risk assessment becomes extremely important to all countries.Introduction & Framework The Legal Framework for PRA

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### IPPC Standards related to risk analysis 

### ISPM No. 2, Framework for Pest Risk Analysis(IPPC, 2007), was originally adopted by the IPPC in 1995 as Guidelines for Pest Risk Analysis and was revised in 2007. This standard has serv ed for more than a decade as the primary conceptual and pr ocedural reference for phyt osanitary risk analyses. This standard provides basic backgr ound regarding risk analysis for phytosanitary purposes and outlines a three-stage process for conducting risk analysis. ISPM No. 2 has been widely used by NPPOs throu ghout the world as a reference outline for developing their phytosanitary risk analysis systems and processes.
ISPM No. 11, Pest Risk Analysis for Quarantine Pests , was adopted in 2001. In 2003, the Interim Commission on Phyt osanitary Measur es (now the Commission on Phytosanitary Measures ), the governing body of the IPPC, adopted a supplement on environmental risks, and in 2004, a supplement on genetically modified organi sms was added (IPPC, 2004a).

In 2004, ISPM No. 21, Pest Risk Analysis for Re gulated Non-Quarantine Pests (IPPC, 2004b), became part of the familyof standards devoted to pest risk analysis. All of these standards provi de significant detail regarding the concepts and practice of risk analysis.
The appropriate level of protection and the acceptable level of risk 

### The SPS Agreement discusses the acceptable level of risk in terms of the appropriate level of protection. In phytosanitary termi nology, the terms “negligible pest risk” and “quarantine security” are also commonly used. Other terms, such as insignificant risk, no significant risk, de minimus risk, and safety are also encountered occasionally in do cuments and discussi ons related to the same or similar concepts.
It is the sovereign right of an importi ng country to establish its appropriate level of phytosanitary protection. The appropriate level of protection (or acceptable level of risk) is not determin ed by the individual risk analyst but is instead determined by broader policy.

In general terms the degree of risk 1 

### accepted is commensurate with the benefits and costs of an alternative. This mean s that although the absolute risk of a particular pest might be significant, it may still fall within an acceptable level of risk (or alternatively, there may be anappropriate level of protection) if, for example, one of the following applies:
 The benefits associatedwith accepting the risk are greater than any associated costs.

1 Risk in this context refers to the likeli hood of pest introduction wi th unacceptable consequences.Introduction & Framework The Legal Framework for PRA

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###  The risk mitigation costs are affordable.  The risk is below what is considered normal or allowable compared to existing risks that are being accepted.  The risk is unchangeable and therefore must be accepted.

The acceptable level of risk is not ne cessarily a “bright-line concept” and should not be expected to be static. The strength of the measures applied in response to the risk should be linke d to sound and open criteria and the measures should be consistent, to the extent possible, with the strength of measures for similar situations.
Provisional and emergency measures 

### The SPS Agreement (SPS WTO, 1995) and th e IPPC (1997) include concepts and terms for provisional and emergenc y measures that may not be well understood or aligned. Other instruments and organizations also refer to socalled “precautionary meas ures” that are variously understood and generally linked to the application of the “pre cautionary approach” (also sometimes known as the “precautionary principle”).
Emergency measures are not explicit inthe SPS Agreement but extend from Annex B paragraph 6 (urgent problem s) and the resulting Emergency Notification format adopted by the SPS Committee (G/SPS/7 Rev 1). Article VII.6 of the IPPC is explicit about “emergency action” based only on the detection of a pest, indicating that suchaction will be evaluated (implying a PRA) as soon as possible to ensure that it is justified. The IPPC’s Principle 14 (ISPM No. 1; IPPC, 2006) refers to em ergency actions for new or unexpected phytosanitary situations based on a pre liminary PRA and indicating that such measures “shall” be temporary and the subject of a detailed PRA as soon as possible.

Provisional measures are referenced in Article 5.7 of the SPS Agreement. Based on the text of the SPS Agreement and relevant jurisprudence to date, such measures have the following characteristics:
 They are taken in the absence of sufficient scientific evidence.  They are based on the avai lable pertinent information (i.e., Members must search for and consider availabl e evidence), including information provided by relevant international organizations (e.g., the IPPC), and information about measures applied by others.  They require that the Member imposing the measure actively pursue the information required for a more objec tive assessment of the risk and review of the measure withina reasonable period of time.Introduction & Framework The Legal Framework for PRA

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### Precaution under the IPPC and SPS 

### The term “precautionary meas ures” is not explicitly usedor described in either the IPPC or the SPS Agreement, although SPS jurisprudence indicates that provisional measures may “r eflect precaution.” It may be argued, however, that phytosanitary measures are by their nature more or less precautionary depending on the influence of uncertainty in the judgment regarding acceptable risk. The concept of precau tion based on uncertainty is therefore implicit in the applicati on of proper risk analysis.
Uncertainty and precaution have a di rect relationship: the higher the uncertainty, the greater the need for a dditional precaution. A properly done risk analysis provides decisi on makers and stakeholders with a clear understanding of the information that ma y be lacking, the variability and possible error in the information used, and the significance of this uncertainty to the conclusions drawn.
Two key points in understanding that the precautionary provisions for agricultural and environmental protecti on are in harmony must be made here. First, the precautionary approach, as described in the Rio Declaration, the Convention on Biological Diversity, and the Cartagena Protocol, is not necessarily incompatible with the I PPC or the SPS Agreement. The second important point is that these envir onmental agreements do not explicitly associate the application of the precauti onary approach with the “failure” of risk analysis. Indeed, they are rather expl icit about risk analys is as the basis for evaluating the available information.
The question is whether a determination regarding the adequacy of information is made before risk analysis is undert aken or completed, or whether the risk analysis is completed and becomes the basis for identifying the uncertainty. This question also points to risk analys is as the starting point for dialogue on the issue and also the starting point fo r harmonization based on the realization of mutual goals for the protection of plant and environmental health from harmful pest invasion.Introduction & Framework The Legal Framework for PRA

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### Rational relationship 

### A key principle of risk analysis (although not described as such in either the IPPC or the SPS Agreement) is the c oncept of rational relationship. This concept has been a central issue in manySPS disputes and is rooted in the linkages between evidence and conclusi ons that are made implicitly or explicitly in both risk as sessment and risk management. The concept has two components: (1) demonstrating an actual cause and effect relationship and (2) demonstrating that the magnitude of th e response is reasonable. For example, there is no basis for assuming that root pests will be associated with fruit; therefore, any risk assigned to fruit for root pests or any measures that may be required would have no rational relationship from a cause and effect standpoint. The second elemen t of rational re lationship follows the idea that the strength of measures is proportional to the risk. The concept here is that the magnitude of the risk and the strength of measures applied to mitigate risk are on sliding scales. Higher risks corres pond with stronger measures and vice versa. Measures do not havea rational relationship withthe risk when they are misaligned based on other ef fective options that may be available. A simple example: a treatment designed for intern ally feeding arthropods may be overly rigorous for external feeders and contaminating pests.
Probable versus possible 

### SPS jurisprudence has made an important distinction between the concepts of probable and possible. Numerous possible scenarios have been put forward in PRAs as the basis for events that repres ent risks without cred ible evidence that such events occur other than expert opinion and assumptions that they are possible. The results of disputes on this point clearly and c onsistently support the position that events that are rele vant to risk analysis under the SPS Agreement must have a demonstrated probability and cannot only be possible. 

## International guidelines for cons idering economic impacts in PRA Guidance found in international agreements and standards is somewhat ambiguous regarding how consequences of introduction should be evaluated, which can result in different inte rpretations by different countries.Introduction & Framework The Legal Framework for PRA

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### Economic analysis guidance in the SPS Agreement 

### The SPS Agreement explicitly endorses co nsideration of risk-related costs (e.g., potential production or sales losses orcontrol and eradication costs) in both assessing risks and managing risks through the choice of an SPS measure to protect animal or plant health. The language in the Agreement suggests that consideration of producer impacts alone would be suffic ient to comply with the letter of the SPS Agreement, and that c hoice of an SPS measure is not required to be justified by an analysis of the effects on producers, c onsumers, taxpayers, and industries that use the re gulated product as an input.
Article 5.3 of the Agreement states:
“In assessing the risk to animal or plant life or health and determining the measure to be applied for achieving the appropriate level of sanitary or phytosanitary protection from such risk , Members shall take into account as relevant economic factors: the potential damage in terms of loss of production or salesin the event of the entry, establishm ent or spread of a pest or disease; the costs of control or eradication in the territory of the importing Member; and the relative cost-effectiveness of alternat ive approaches to limiting risks .”

In addition, Article 5.6 states that Member s must ensure that their measures are not more trade restrictive than necessary to achieve their appropriate level of protection; however, what is meant by “not more trade restrictive than necessary” and whether this term has implications for economic consequence analysis in PRA is a matter of interpretation.
IPPC guidance to economic consequence analysis in PRA 

### Several ISPMs (e.g., ISPMs No. 2, 5, and 11) either reference economic considerations or provide gu idance that is applicable to economic analysis in a pest risk assessment. The overall importance of economic considerations in phytosanitary decision-making is suggested by the number of key phytosanitary concepts that referen ce economic terms. In ISPM No. 5, Glossary of phytosanitary terms (IPPC, 2012), the phrases “economic impacts” and “economic cons equences” are explicitly mentioned in definitions of several important phytos anitary terms such as “pest risk,” “pest risk assessment,” “phytosanita ry measure,” and “phyt osanitary regulation.” “Economic importance” and “economically important losses” are explicitly mentioned in the definitions of other terms, including the definition for the key phytosanitary concept of “quarantine pest .” The glossary does not include a definition for any of the terms related to economic impacts or economic importance but does cont ain a supplement that provides guidelines for understanding them (IPP C, 2012, Supplement 2).Introduction & Framework The Legal Framework for PRA

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 1-12 Supplement No. 2 to I SPM No. 5 (IPPC, 2012). 

### The scope and purpose of the supplement is to provide cl arification to ensure that economic terms are clearly understood and consistently applied and to illustrate certain economic principles as they relate to the IPPC’s objectives, in particular but not limited to environmental considerations. The supplem ent clearly states that the IPPC can account for environmental concerns ineconomic terms using monetary or nonmonetary estimates and that market impacts are not the sole indicator of pest consequences.
Section 4 of the supplem ent to the glossary, Economic Considerations in PRA
, discusses types of economic effects and costs and benefits. It describes a relatively inclusive approach to economic considerations in PRA, indicating that all economic effects (not just market related), both costs and benefits, and both direct and indirect effects, should be considered in PRA. It affirms the cost-benefit criteria for decision making, whereby policies should be pursued if benefits are at least as la rge as costs, and indicate s that judgments about the preferred distribution of costs and bene fits are a policy choice to be made outside the context of the economic analysis.

ISPM No. 2, Framework for pest risk analysis (2007a). 

### ISPM No. 2 does not give specific guidance on how economic impacts should be conceptualized or measured, but describes the stages in a pest risk assess ment and indicates where it is appropriate toconsider economic factors:  Pest categorization: to determine whether a pest is “of potential economic importance.”  Pest risk assessment: to a ssess potential economic impacts  Pest risk management: to determine whether or not appropriate phytosanitary measures to reduce pest risk to an acceptable level are available, cost-effective, and feasible . In addition, the ISPM indicates that PRA documentation should include evidence of economic impact [emphasis supplied], and evaluati on of risk management options.

ISPM No. 11, Pest risk analysis for quarantine pests, including analysis of environmental risks and living modified organisms (2004a). 

### ISPM No. 11 Section 2.3, Assessment of potential economic consequences , contains the most fully elaborated description of the process for assessing economic consequences in the pest categorization st age of a risk assess ment, but contains such broad guidance that it leaves many questions unanswered about what should be measured and how it should be measured.
The guidelines discuss situations in wh ich a detailed analysis of economic consequences may or may not be necessary . If it is widely agreed that pest introduction will have unacceptable cons equences, detailed analysis may notIntroduction & Framework The Legal Framework for PRA

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### be necessary. On the other hand, it may be necessary to examine economic factors in greater detail when the level of consequences is in question, or when consequences are needed to evaluate th e strength of measures, or to assess the relative benefits of ex clusion versus control.
The guidelines indicate that both direct and indirect effects of the pest should be identified and analyzed. In evaluati ng direct effects, which include effects of the pest on the potential host or the environment, the guidelines specify that the total crop area and/or potentially e ndangered area should be identified. Examples of direct effects on cultiv ated hosts could include crop losses, control measures, and effect s on production practices. Dir ect effects of the pest on the environment could include reducti on of keystone species or endangered native plants. Examples of indirect effe cts of the pest in the PRA area include effects that are not host- specific, such as effect s on domestic and export markets (i.e., loss of export markets), changes to demand because of quality changes in the commodity, and social or other effects.
Summary SPS Agreement and ISPM guidance on economic consequences 

### The SPS Agreement describes a more limited set of factor s to be considered in economic assessments than do the ISP Ms. This distinction is important because different approaches describe d in the SPS agreement and the ISPMs (i.e., estimating negative impacts to producers as opposed to estimating both costs and benefits) will af fect what is measured, how results are interpreted, and could support different conclusi ons regarding risk management by decision makers.
The SPS Agreement explicitly endorses co nsideration of risk-related impacts to producers in the importing country. Th e ISPMs describe a very broad range of approaches to economic consequence analysis in PRA, with ISPM No. 11 emphasizing the inclusion of envi ronmental impacts and endorsing a continuum of approaches ranging from “n o detailed analysis” if consequences are widely viewed to be unacceptable, to qualitative analysis, to various approaches of quantitative analysis, which include consideration of relevant impacts on consumers, producers, and domestic and foreign markets. Based on available guidance in the SPS Agreement and the ISPMs, and in the absence of any clarifying WT O jurisprudence or case la w, it may be concluded that risk assessment practitioners have considerable latitude in determining how to approach economic consequence an alysis in PRA. This latitude would be subject to the conditions that any phytosanitary measures based on a risk assessment and economic consequenc e analysis should not violate the consistency provisions of the SPS Agr eement by arbitrarily or unjustifiably discriminating between Members and should not be applied in such a way as to constitute a disguised restriction to trade.Introduction & Framework The Legal Framework for PRA

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## National legislative framework for PRA The Plant Protection Act (PPA; 7 U.S.C. § 7701-7786, 2000) became law in June 2000 as part of the Agricultur al Risk Protection Act. The PPA consolidates all or part of 10 USDA pl ant health laws into one comprehensive law, including the authority to regu late plants, plant products, certain biological control organisms, noxious weeds, and plant pests. The Plant Quarantine Act, the Federal Pest Act, and the Federal Noxious Weed Act are among the 10 statutes the new Act replaces . The PPA is necessary because of the major impact plant pests currently have and could have on the agriculture, environment, economy, and commerce of the United States.
The following provisions of the PPA are important in relation to pest risk analysis associated with importati ons of plants and plant products:
“...the Secretary shall publish for publ ic comment a notice describing the procedures and standards th at govern the considerati on of import requests. The notice shall—
1. specify how public input will be sought in advance of and during the process of promulgating regulations necessitating a risk assessment in order to ensure a fully transparent and publicly accessible process; and 2. include consideration of the following:  Public announcement of import reques ts that will necessitate a risk assessment.  A process for assigning major/non-r outine or minor/routine status to such requests based on current state of supporting scientific information.  A process for assigning priority to requests.  Guidelines for seeking relevant scie ntific and economic information in advance of initiating informal rulemaking.  Guidelines for ensuring availability and transparency of assumptions and uncertainties in the risk asse ssment process including applicable risk mitigation measures relied upon individually or as components of a system of mitigative measures proposed consis tent with the purposes of this title.”Introduction & Framework The Legal Framework for PRA

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### Relationship of the PPA to the WTO-IPPC framework 

### From a legal standpoint, there is animportant distinction to understand regarding differences between the Pl ant Protection Act (PPA)–our national authority for the implementation of pl ant protection programs and actions–and the WTO-IPPC framework, including all of the obligations, responsibilities, and guidance relevant to N PPOs such as PPQ. The le gal ramifications for PRA are not the same and the terminology and concepts are not entirely consistent on many important points.
One key difference regards the lack of consistency between the PPA concept of regulated pests and the WTO-IPPC conc ept of the same. The PPA provides the Secretary of Agriculture (APHIS by dele gation) the authority to regulate any pest deemed to be harmful whether or not it meets the defining criteria of the IPPC. This authority is necessary fo r the USDA to implement programs for domestic pests (whether exotic, naturali zed, or native). For example, the PPA does not link noxious w eeds to quarantine pests in order to provide USDA with the flexibility to implement program s for domestic weeds. As a result, referring to “noxious weeds” in a PRA fo r imported articles represents a shift from the IPPC concept of a regulated pe st (a quarantine pest or regulated nonquarantine pest) to the PPA concept, wh ich may include the IPPC concept but is not limited to it.

Another area where the WTO-IPPC fram ework must be interpreted against national policies is in the determination of pest status for purposes of pest listing in the PRA. The list of pest s requiring analysis in the PRA should include all organisms for which the cu rrent national policy is to require phytosanitary measures (acti onable pests). This includes organisms that meet the IPPC definition of a quarantine pest, but it also extends to other types of pests, including those that are establis hed in the United States but are under consideration for official c ontrol and other pest taxa that for policy reasons are considered to require quarantine acti on. For example, taxonomic groups that are commonly intercepted in immature form and cannot be identified to species level may require action for the entire taxa (usually genus) because one or more species in that genus are quarantine pests.
The reverse may also be true. Pests th at meet the defining criteria for a regulated pest may not require action inall circumstances. For example, the current policy for armored scales that meet the internationally agreed criteria for a quarantine pest is to require action if associated with propagative material but not on fruit for consumption, because fruit is consid ered to be a negligible risk for introduction whereas plan ts are an excellent pathway.

Other such differences exist that make it important for analysts to pay close attention to concepts and terminology in the PRA process. One way to do this is to think about the analysis from the standpoint of potential legal challenges.Introduction & Framework The Legal Framework for PRA

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### A point that might be challenged in a U.S. court will be reviewed, argued, and ultimately judged against the authority of the PPA. A U. S. judge willhave little interest in arguments based on the IPPC/WTO framework. Likewise, a challenge raised by a trading partner w ill be judged against the IPPC and the WTO, especially the SPS Agreement, wh ere our domestic legal situation may have some bearing on the background but the central issue wi ll ultimately be decided against the relevant international authority.Introduction & Framework The Legal Framework for PRA

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## Climate change in PRA Climate change affects the ab ility of a plant pest to en ter, establish, and spread in new environments. There are so me challenges in making specific predictions about the effect of climate change on pest behavior. Members of the North American Plant Protection Organization’s (NAPPO’s) Pest Risk Analysis and Invasive Species Pane ls developed a discussion paper, C limate Change and Pest Risk Analysis(NAPPO, 2012), in which they considered issues related to climate change in PRA and identified several challenges.
The biggest challenge to effectively ad dressing climate change in PRA relates to the time horizon for climate change and the length of time for which a PRA is considered valid. Climate change mo dels are generally based on projections of at least 20 year s (Hellman et al., 2008), while PRAs often focus on a shorter time frame and may be updated when new information becomes available. Pest risk analyses represent the knowledge available at the time they were conducted—they are a “snapshot in time.” Consideration of future events and impacts is also limited to relatively short projections in time; however, the specific length of time that a given PRA is valid is not precisely defined. The time horizon for routine commodity PRAs is understood to be less than 20 years, which is the time horizon fo r seeing effects of climate change. Therefore, it is beyond the scope of thes e Guidelines to attempt assessing the effect of climate change on pest behavior.

Furthermore, models used in PRA for predicting climate change and simulating the impact of climate changeon species distributions may increase uncertainty to the point of compromisi ng their utility. Climate change models usually address information at a global scale and may not be fine-tuned for predictions at the local or regional levels needed for most PRAs.
In addition to the scientific challenges involved in considering climate change in PRAs, the SPS Agreement requires thatmeasures be based on evidence and least trade restrictive. A risk assessm ent is intended to provide sufficient evidence that a chosen measure(s) is not arbitrary, unjustifi ed, or a disguised barrier to trade. Therefore, climate ch ange projections within a PRA must be sufficiently robust to meet these requireme nts. Specifically, sufficient scientific evidence is required to show a causal link between climate change and the risk being assessed.
The interaction of climate change with ch anges in trade patterns will increase the need for new PRAs and for revision of existing ones to take into account changes in pest distribution and the likelihood of their associations with pathways (EFSA, 2007). However, the decision about whether or not to consider climate change scenarios or incorporate complex models into a PRA will depend on feasibility, goals, and th e rigor of the available scientific support. Climate modeling can be co mplex, time-consuming, and resource-Introduction & Framework Overview of the PPQ Risk Assessment Mode l for Commodity Imports for Consumption

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### intense, and it may not be necessary to answer the question at hand.



# Overview of the PPQ Risk A ssessment Model for Commodity Imports for Consumption
Overview of the model Risk is a product of the likelihood of anadverse event—in this case, a pest introduction—and the magnitude of the c onsequences. We separately rate the uncertainty during each process in the ri sk assessment and provide a summary of the uncertainties associated wi th the overall risk rating. In Figure 1-1 , we depict the conceptual model for the process.Introduction & Framework Overview of the PPQ Risk Assessment Mode l for Commodity Imports for Consumption

1-19 Guidelines for Plant Pest Risk Assessment ofImported Fruit & Vegetable Commodities 08/2012-1 Figure 1-1. Processes overview. Procedures are in parentheses.Introduction & Framework Overview of the PPQ Risk Assessment Mode l for Commodity Imports for Consumption

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## Volume of consignments consideration In these Guidelines, we do not includevolume as an element to be rated. Although we recognize that volume can affe ct the level of risk (e.g., increased volume has the potential to increase risk), it is difficult, if not impossible, to accurately predict or control the volume of importations or the effect on risk. Following are some of th e factors related to volum e that can affect risk:
 Seasonal timing of c onsignments (e.g., winter vs. summer).  Frequency and volume over time (e .g., a few large consignments vs. multiple small consignments).  Changes to the proposed frequency and volume of exports (both increases and decreases).  Proposed destinations for export markets.

Therefore, for the purposes of these Guidelines, we will use the volume proposed in the prerequisite information and assume that any proposal to export a commodity for commercial purposes will represent a significant enough volume of trade to affect risk. If the analyst judges, based on evidence, that changes in the initially proposed vol ume of trade will significantly affect risk, this will be noted in relation to risk management. This is particularly important if inspections are key to risk management. 

## Pathway considerations Agricultural commodities move through di fferent steps in international trade, from the field and packinghouses at the farm, through export-import brokers, to retailers and, finally, to consumers, and perhaps into the environment. While most pests may first become associatedwith the commodity (pathway) at the farm, pests may also enter or exit the pathway at any stage until arrival in the importing country or area ( Figure 1-2 ). The risk of escape into a new environment does not begin until the co mmodity has arrived in the PRA area. This may be problematic when the pest treatment facility is located in the PRA area (as can be the case, for instance, w ith irradiation), before the risk is adequately mitigated. Most pests associated with commodities for consumption have a low likelihood for establishment.
Pest populations on agricultural commodi ties will generally decrease as commodities move through the process, particularly with effective postharvest processing measures ( Figure 1-3 ). Increases in pest population size are rare and most likely would be associ ated with re-infestation or conditions conducive to the organisms’ growthand development during storage and shipping (e.g., pathogens, arthropods reproducing parthenogenetically).Introduction & Framework Overview of the PPQ Risk Assessment Mode l for Commodity Imports for Consumption

1-21 Guidelines for Plant Pest Risk Assessment ofImported Fruit & Vegetable Commodities 08/2012-1 Figure 1-2. Pest presence on agricultural commo dities can change as a result of harvest and post-harvest processing measures from harvest through shipping. This figure represents general harvest and post-harvest processes and is not intended to be comprehensive.

Figure 1-3. An example of anticipated decrease in pest populations on commodities for export as they move through harvesting and post-harvest processing.Introduction & Framework Overview of the PPQ Risk Assessment Mode l for Commodity Imports for Consumption

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## The endangered area The area within the PRA area that ha s the identified biotic and abiotic conditions favorable for a pest’s establis hment is identified as the “endangered area.” We define the area endangered by each pest by determining the portion of the PRA area where suitable hosts fo r that pest occur overlaid with portion of the PRA area where suitable envir onmental conditions also occur. Once a pest has entered the PRA area, it must beable to establish and subsequently spread in order for there to be conse quences. The likelihood that a pest will establish (i.e., be able to survive, repr oduce and/or perpetuateitself into the foreseeable future) is dependent on the pest overcoming biotic and abiotic resistance in a new area. A nother way of stating that is that the pest must find suitable conditions in the PRA area to establish. Those conditions include biotic factors (availability of host material, presence or absence of natural enemies, etc.) and abiotic factors (e.g., temperature, season, humidity, rainfall or other environmental conditions that affe ct the ability of the pest to survive and reproduce).



## Likelihood of introduction We qualitatively assess the likelihood of introducti on as Negligible, Low, Medium, or High. The like lihood of introduction is ba sed on the likelihoods of entry and establishment. The likelihood of entry depends on the pest being associated with the commodity and surviving or remaining with the commodity throughout the entire post- harvest and shipping processes. The likelihood of establishment depends oncharacteristics of the pest and suitability of the PRA area. The ri sk factors comprising the model for likelihood of introduction are interdepende nt and the relationship is therefore multiplicative. Thus, if any risk factor is rated as Negligible, then the overall likelihood will be Negligible. 

## Potential consequen ces of introduction We determine if the pest is likely to cause unacceptable impacts in the PRA area upon introduction by considering the potential direct and indirect impacts in relation to a hypothetical situation wher e the pest is supposed to have been introduced and to be fully expressi ng its potential economic consequences throughout the endangered area. This evaluation is made by obtaining information on the types of impacts curr ently being caused by the pest in areas where the pest occurs naturally or ha s been introduced. Spread potential is evaluated as a component of potential consequences because the expression of potential economic conseque nces depends on the rate and manner of spread in the PRA area. Our analysis of spread potential focuses on determining whether the pest is likely to be able to sp read throughout the e ndangered area quickly enough to result in economically important losses.Introduction & Framework Overview of the PPQ Risk Assessment Mode l for Commodity Imports for Consumption

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### Pests that are unlikely to cause unacceptable impacts are call ed “non-threshold pests” because their total impacts are not expected to reach the threshold of damage that would warrant additional phytosanitary measures within a reasonable period of time. 

## Uncertainty analysis Estimating pest risk involves many unc ertainties, in large part because assessors have to extrapolate from the current situation of the pest to a novel situation in the PRA area. Two major types of uncertainty in analyzing risk are (according to Merrick and van Dorp, 2006)
 the randomness of the system itself, in cluding natural variability (aleatory uncertainty) and  the lack of knowledge about the system (epistemic uncertainty).
Uncertainty due to variability among i ndividuals is inherent in biological systems and should be measured or de scribed. New or additional information will not usually reduce uncertainty arising from variab ility. Uncertainty due to lack of knowledge may be reduced by further study and data collection. In reality, the clear distinction between variability and uncertainty from lack of knowledge is not always possible to make and may be dependent on the context. Furthermore, most risk as sessments deal with both types of uncertainty concurrently. The distinctio n between two types of uncertainty is, however, important when explaining mode l results to decision makers or the public and when expending re sources for data collection.
Common sources of uncertainty include  old/dated information,  conflicting information,  absence of information,  extrapolation of information av ailable for congeneric organisms,  reliance on expert judgment and c onflicting or vague opinions from experts, and  incorrect assumptions or models.
Documenting the degrees and types of uncertainty in the assessment and indicating where expert judgment has beenused is important. This increases transparency and may help identify and prioritize research needs.
Separating the uncertainty th at arises due to lack of knowledge from the ratings of risk elements is important; ratings should be based only on the available evidence, not the uncertainty associated with the evidence. For instance, aIntroduction & Framework Overview of the PPQ Risk Assessment Mode l for Commodity Imports for Consumption

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### given risk element should not be rated higher if there is a lot of uncertainty; rather, the rating should be assigned ba sed on available evidence and the high level of uncertainty should be noted. At the same time, werecognize that a given risk element may be assigned a rating that may more or less accurately reflect the actual probability associatedwith that risk element, depending on the level of uncertainty. Higher levels of uncertainty could mean a given rating may be over- or under-esti mating probability by one or more levels (e.g., a low rating with high uncertainty would truly be medium or high if we had more evidence on which to base our judgment). In cases with a high degree of variability, the analyst will typically make a conservati ve judgment resulting in a higher risk rating. This undersco res the importance of describing uncertainty—including sources and ma gnitude—while at the same time maintaining judgments that are based on available evidence.
The feasibility of reducing uncertainty sources depends on the type of uncertainty, the possibility of gaining fu rther data, and applying more reliable assessment methods. The application of quantitative uncertainty assessment (tiers 2 and 3 in EFSA, 2006) is generally recommended after the qualitative uncertainty assessment has been perf ormed in order to point out the uncertainty sources for addressing later in the quantitative evaluation and for considering those uncertainties thatcannot be quantified (Colyvan, 2008; EFSA, 2006). 

## Overall risk rating The concerns of the public and most deci sion makers focus on events with dire consequences, even if these events have low probabilities of occurring. Yet, models have been helping to mask th e criticality of cat astrophic events by adhering to the expected value of ris k, which intrinsically can equate a low probability of high-consequence even ts with a high probability of lowconsequence events. The reliance on this commonly used metric, when it is used as the sole measure of risk, can confuse the decision makers, leading to bad choices. The problem is that the expe cted value of risk is an operation that essentially multiplies the consequences of each event by it s probability of occurrence and adds all these products over the entire probability range (Haimes, 2009). Transparency resulting from separating es timates of overall risk due to impact and due to likeli hood allows implemen tation of mitigation measures that are most approp riate for each of the risks.
The overall pest risk is pr esented as a table depicting, for each individual pest, the specific risk rating for the likeli hood of introduction, the determination of whether or not the pest is likely to cause unacceptable impacts, and the uncertainties associated with the ratings (see Process 9: Summarizing the final risk ratings and uncertaintyfor more detail).Introduction & Framework Overview of the PPQ Risk Assessment Mode l for Commodity Imports for Consumption

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## Risk mitigation documentation Throughout the analysis, the analyst will collect information on both the pathway (e.g., the commodity being exported) and the pests. Much of the information gathered during risk assessmen t is also useful to risk management. Moreover, the risk assessment should inform and guide risk management (rather than simply act as a trigger), an d the risk analyst is in the best position to provide information relevant to the development of risk management options. In Process 10: Risk mitigation notes , we provide more detailed guidance on the types of information gath ered during risk as sessment that are particularly relevant to risk manageme nt. We also provide a template and an example for communicating that in formation to risk managers. 

## Summary of processes In Table 1-1 , we summarize the main processes in the PPQ pest risk assessment model for comm odity imports. Each proce ss will be discussed in more detail in Conducting Pest Risk Assessment in PPQ

. Process 7: Assessing the likelihood of introductionand Process 8: Assessing potential consequences of introduction can be performed in either order, as appropriate. Pests that have a Negligib le likelihood of being introduced do not usually need to be assessed for conseque nces; similarly, pest s that are unlikely to cause unacceptable economic consequenc es do not need to be analyzed for likelihood of introduction. Desc ribing uncertainty is an important part of every process, but is explicitly assessed in terms of the risk ratings determined in Processes 7 and 8.

Table 1-1. Summary of the processes that comprise PPQ’s risk assessment model for commodity imports for consumption. Stage 1. Initiation Process 1: Documenting the initiating event and scope

. Describe the reason(s) for conducting the risk assessment and some of the background information regarding the proposed importation. Process 2: Determining if a weed risk assessment for the commodity is needed

. Process 3: Defining the pathway

. Describe the pathway based on information about the commodity, information provided by the exporting country regarding production practices, and processing of the commod ity; state any assumptions. Process 4: Creating the pest list and pest categorization

. Compile a comprehensive list of all potential pests known to occur in the exporting country or region that are known to be associated with the host plant from anywhere in the world. Identify pests meeting criteria for further analysis. Stage 2. Pest Risk Assessment Process 5: Collecting information and defining the endangered area

. Gather the information necessary to complete the risk assessment (Processes 7 and 8). Based on available in formation, determine whether Process 7 or 8 should be completed first. Process 6: Assessing uncertainty for risk elements

. Process 7: Assessing the likelihood of introduction

. Estimate the likelihood of introduction (entry and establishment). Entry and establishment are evaluated as Risk Elements A and B, respectively. Pests that are rated Negligible at any stage do not need to be evaluated further.Introduction & Framework Overview of the PPQ Risk Assessment Mode l for Commodity Imports for Consumption

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Process 8: Assessing potential consequences of introduction

. Determine if the pest is likely to cause unacceptable economic consequences. Direct impacts are evaluated as Risk Element C, and trade impacts are evaluated in Risk Element D. Process 9: Summarizing the final risk ratings and uncertainty

. Stage 3. Risk Management Process 10: Risk mitigation notes

. Provide important information on pest biol ogy, pathway, and uncertainty relevant to risk management. Table 1-1. Summary of the processes that comprise PPQ’s risk assessment model for commodity imports for consumption. Stage 1. Initiation08/2012-1 Guidelines for Plant Pest Risk Assessmentof Imported Fruit & Vegetable Commodities 2-1 

### Section 

# 2 Conducting Pest Risk Assessment in PPQ

Stage 1: Initiation Initiation is the first stage of pest risk analysis and consists of defining the specific scope of the analysis and identi fying the pests of concern that will be analyzed in the risk assessment. In PPQ commodity import risk assessment, the Initiation stage is completed using th e following four processes (as outlined in the previous section in Table 1-1 on page 1-25 ):
 Process 1: Documenting the initiating event and scope  Process 2: Determining if a weed ri sk assessment for the commodity is needed  Process 3: Defining the pathway  Process 4: Creating the pest list and pest categorization

NOTE As outlined in ISPMs No. 2 and 11, pest cate gorization is actually a part of pest riskassessment (Stage 2); however, for practical purposes the first part of pest categorization, determining whether pests are acti onable, occurs as the pest list is developed (see Process 4: Creating the pest list and pest categorization on page 2-9 ).Conducting Risk Assessment in PPQ Process 1: Documenting the initiating event and scope

08/2012-1 Guidelines for Plant Pest Risk Assessmentof Imported Fruit & Vegetable Commodities 2-2 

## Process 1: Documenting the initiating event and scope In Process 1, we document why the risk assessment was initiated and describe its scope. In most cases, a risk assessment is initiated to evaluate the pest risk associated with a new importation request. Additi onal possible initiating events are listed in ISPMs No. 2 (IPPC, 2007) and 11 (IPPC, 2004a). The initiating event of the risk assessment must be documented, but before we initiate a risk assessment, we need to determine if the risk assessment is actually needed. If a previ ous risk assessment exists and adequately addresses the risks posed by the proposed commodi ty importation into the PRA area from the export area in question, the cu rrent risk assessmen t process may stop at this point.
Scoping is the process step during which the risk analysts and PPQ headquarters staff, usually during a conf erence call, determine the scope of the risk assessment. The scope of a risk as sessment includes th e commodity(ies) to be imported, export area(s), PRA area, field and/or harvest procedures to be considered when assessing pest risk, and other details that pr ovide the basis for the risk assessment and all other subsequent decisions.


## Procedure 1-1. Determining if a new or revised risk assessment is needed

Follow steps 1-3 to determine if a new or revi sed risk assessment is needed for the commodity. Step 1 Determine whether any previous risk assessments have been completed for the requested or a sufficiently similar (neighboring country; close relati ve of plant species) commodity/country combination. If an assessment already exists, go to Step 2 . If a new assessment is needed, go to Step 3

. Step 2 If a risk assessment already exists, determine w hether it adequately addresse s the current risks in question. Consider the following:  Is the pest list complete?  Have pest distributions or information on biol ogy changed since that original risk assessment was completed?  Have phytosanitary policies and/or regulation s changed since that risk assessment was completed? If the existing risk assessment adequately addresses the risks posed by the proposed importation of the commodity, no new risk assessment needs to be initiated. If a revised assessment is needed, go to Step 3

. Step 3 In the “Initiating Event” section of the risk assessm ent, briefly state the reason why a new or revised risk assessment is needed. If a new or revised risk assessment is needed, continue to Procedure 1-2: Documenting the initiating event

.Conducting Risk Assessment in PPQ Process 1: Documenting the initiating event and scope

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## Procedure 1-2. Documenting the initiating event

State the following in the “Initiating Event” section of the risk assessment. Name and affiliation of the requestor Of the plant species to be imported:  the valid scientific name and common synonyms  common name(s)  cultivar/variety/race/etc. (if applicable)  plant part(s) to be imported (e.g., root, fruit, leaf)  condition of the plant parts to be impo rted (fresh, dried, processed, etc.)  seasonality of imports (if applicable) The export and PRA areas The reason why the risk assessment is needed (see Procedure 1-1: Determining if a new or revised risk assessment is needed ). For example:  The requested commodity importat ion into the requested PRA area is currently not authorized.  The commodity is currently permitted into a portion of the United States, but requestor wishes to expand the market (importing area).  The commodity is currently permitted from a portion of th e exporting country, but requestor wishes to expand the exporting area.  Importation of the commodity with add itional plant parts is requested.  The pest risk associated with the commodity has changed or is expected to change. For example:

 New mitigation measures for the commodity ar e proposed or implemented (e.g., irradiation)  There is reason to believe (based on scientific studies or port-of-entry interceptions ) that a new pest associated with the commodity has become est ablished in the exporting area.  New information indicates that a pest is likely to be more damaging in the PRA ar ea than originally determined.
Continue to Process 2: Determining if a weed risk assessment for the commodity is needed on page 2-4

.Conducting Pest Risk Assesment in PPQ Process 2: Determining if a weed risk assessment for the commodity is needed

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## Process 2: Determining if a weed risk assessment for the co mmodity is needed In some cases, the imported commodity may have the potential to propagate and become invasive in the PRA area. The likelihood that this may happen is evaluated in a weed risk assessment, conducted separately from the commodity pathway risk assessment. A weed risk assessment need only be conducted under certain conditions. The project l ead of the commodity pathway risk assessment is responsible for determining whether or not a weed risk assessment may be required and referring the plant for further analysis.


## Procedure 2-1. Determining if a weed risk as sessment for the commodity is needed

Follow steps 1-4 to determine whether a weed risk assessment is necessary. Because not all plant parts of every commodity are capable of propagation, consider not only the species proposed for import, but also the form in which the commodity will be imported.

IF THEN Step 1 The commodity is already enterable into the PRA area from other countries. A weed risk assessment is not needed. In the “Determination of the necessity of a weed risk asse ssment for the commodity” section of the risk assessment, state that an assessment of weed risk potential is not required because the commodity is already enterable from other countries. Provide references. Continue to Process 3: Defining the pathwayon page 2-6

. The commodity is not enterable i nto the PRA area from other countries. Go to Step 2

.

Step 2 The plant species is widely established (native or naturalized) in the PRA area. (If questionable, consult the weed team.) A weed risk assessment is not needed. In the “Determination of the necessity of a weed risk asse ssment for the commodity” section of the risk assessment, state that an assessment of weed risk potential is not required because the commodity is already widely established in the PRA area. Provide references. Continue to Process 3: Defining the pathwayon page 2-6

. The plant species is not widely established (native or naturalized) in the PRAarea. (If questionable, consult the weed team.) Go to Step 3

.

Step 3 Any part of the imported commodity can easily propagate or be propagated. Go to Step 4

.

The imported commodity cannot easily propagate or be propagated. A weed risk assessment is not needed. In the “Determination of the necessity of a weed risk asse ssment for the commodity” section of the risk assessment, state that an assessment of weed risk potential is not required because the pl ant parts to be imported cannot be propagated. Provide references. Continue to Process 3: Defining the pathwayon page 2-6

.Conducting Pest Risk Assesment in PPQ Process 2: Determining if a weed risk assessment for the commodity is needed

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Step 4 A weed risk assessmenthas already been completed for this species. A weed risk assessment is not needed. In the “Determination of the necessity of a weed risk asse ssment for the commodity” section of the risk assessment, state that an assessment of weed risk potential has already been completed. State the conclusions of the assessment and provide references. Continue to Process 3: Defining the pathwayon page 2-6

. A weed risk assessment has not already been completed for this species. A weed risk assessment may be required. Notify the weed teamand in the “Determination of the necessity of a weed risk assessment for the commodity” sectio n of the risk assessment, state “Because the commodity has the pot ential to be propagated, an assessment of weed potential may be required before importation of the commodity plant species is au thorized. If required, the weed potential will be analyzed separately and will not be included in this document.” Continue to Process 3: Defining the pathwayon page 2-6

. 

## Procedure 2-1. Determining if a weed risk as sessment for the commodity is needed

Follow steps 1-4 to determine whether a weed risk assessment is necessary. Because not all plant parts of every commodity are capable of propagation, consider not only the species proposed for import, but also the form in which the commodity will be imported.

IF THENConducting Pest Risk Assesment in PPQ Process 3: Defining the pathway

08/2012-1 Guidelines for Plant Pest Risk Assessmentof Imported Fruit & Vegetable Commodities 2-6 

## Process 3: Defining the pathway The IPPC (2012) defines a pathway as “any means that allows the entry or spread of a pest.” In the context of commodity pest risk assessments, the pathway is the commodity to be importe d, together with all the processes it undergoes from production to importation and distributi on in the PRA area that may have an impact on pest risk.
A detailed description of the path way, including the morphological and physiological characteristics of th e commodity, provides the necessary foundation for the risk assessment.

NOTE All components of the pathway, as they are described in the risk assessment, become mandatory conditions for importation of the commodity. Therefore, the pathway description should ultima tely only include those components of the pathway that will actually be used the risk assessment as a basis for identifying the potential pests associated with the commodity and evaluating their risk.Conducting Pest Risk Assesment in PPQ Process 3: Defining the pathway

2-7 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 08/2012-1 

## Procedure 3-1. Defining the pathway

Based on the scope of the risk assessment, provide a detailed description of the pathway that includes the information listed in this procedure. All components ofthe pathway used in the risk assessment as a basis for evaluating pest risk become mandatory conditions for importation of the commodity. The commodity to be imported, including  plant part(s) to be imported (e.g., root, fruit, leaf) and in clusion/exclusion of specific ot her plant parts (e.g., stems, calyces, husks).  condition at the time of entry (e.g., fresh, dried, processed).  cultivar, variety, race, colors, variability, grade, size, re strictions (e.g., kosher), or other pertinent information.  expected end-use (e.g., co nsumption, milling, etc.).  stage of maturity at time of harvest.  stage of maturity at time of import. Production and harvest procedures in t he exporting area that will be explicitly considered during the risk assessment. Examples include  growing conditions (e.g., gr eenhouse, overhead irrigation).  specific pest control or exclusion prac tices such as area freedom, biological co ntrol, pheromone disruption, routine pesticide application (including target pests of the treatments).  planted crop (e.g., clean stock, host-resistance). If the planted crop is to be from certified seed ornursery stock, indicate the origin of the stock or seed (country, state).  cultural practices such as sanitation, planting date, harv est timing, crop rotation, etc.  method of harvesting (e.g., manual, clipped, machine-harvested, selective harvesting). Post-harvest procedures in the exporting area that will be explicitly considered during the assessment. Examples include  processing procedures such as chippi ng, washing, brushing, waxing, sieves.  quality procedures such as cu lling, quality inspections.  pest exclusion practices such as enclosures, screens.  treatments (including target pests) such as dips, cold tr eatment/refrigeration, fumigatio n, irradiation, fungicide applications, hot water vapor treatments.  packing, boxing, and wrapping methods including special enclosures/protections, packaging, etc. Shipping and storage conditions that will be explicitly considered duri ng the assessment. Examples include  storage duration and conditions (e.g., cold storage, modified humidity).  shipping methods (e .g., truck, cargo).  transit time.  timing of consignments (season). A visual depiction of the pathway. Figure 2-1 provides a generic depiction, but the specific details and the level of detail will vary from case to case.
Continue to Process 4: Creating the pest list and pest categorization on page 2-9

.Conducting Pest Risk Assesment in PPQ Process 3: Defining the pathway

08/2012-1 Guidelines for Plant Pest Risk Assessmentof Imported Fruit & Vegetable Commodities 2-8 Figure 2-1. A generic graphic representation of a commodity pathway.Conducting Pest Risk Assesment in PPQ Process 4: Creating the pest list and pest categorization

2-9 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 08/2012-1 

## Process 4: Creating the pest list and pest categorization In this process, we identify the plant pe sts that could become established in the PRA area as a result of the importati on of the commodity and determine which of these pests meet the criteria for further analysis. The pests selected for further analysis are those whose a ssociation with the commodity pose a specific hazard to the PRA area because they are of regulatory significance and have a reasonable likelihood of bei ng associated with the harvested commodity.
Identifying pests for the pest list 

### The process begins when we develop a li st of pests in the export area that are known to be associated with the commodity anywhere in the wo rld and to be of regulatory significance to the PRA area. Pests are considered to be of regulatory significance if they are “ actionable” at U.S. ports of entry. Actionable pests include quarantine pest s, regulated non-quarantine pests, pests considered for or under official c ontrol, and pests that require evaluation for regulatory action. Refer to National legislative framework for PRA on page 1-14 for more details regarding national pol icies determining pest status for the purpose of pest listing in the risk a ssessment. Non-actionable pests that are present in the exporting area and known to be associated with the commodity are not placed on the pest list. Instead, these pests are recorded in a separate table along with supporting evidence in an appendix to the risk assessment.
In general, we do not include pests on the pest list if the only evidence of presence in the exporting area is weak or dubious (e.g., very few interceptions in permit cargo, only interceptions inbaggage from the exporting country, other evidence refutes any reports of pest presence in the host country). We list any pests with a doubtful distribution in th e export area before the pest list in the “Pests considered but not included on the pest list” section.
Similarly, we only list pests for which the commodity is a Type 1 host (natural host) or Type 2 host (conditional host) (refer to Supplement 3: Host Status on page 3-10 for an explanation of host types) . If the evidence of host association is insufficient to conclude that the comm odity is a Type 1 or Type 2 host, we do not list such pests. Instead, we list them in the “Pests considered but not included on the pest list” section. If th ere is evidence of a non-actionable vector in the exporting area that tran smits an actionable pest, we list the actionable pest in the pest list and analyze it if appr opriate; if we determine the actionable pest is a candidate for risk management, relevant information about the vector is included in the risk miti gation notes. Type 4 hosts (fomites) are included on the list if there is clear evidence that the commodity is a common pathway for the movement of the pest.
In general, we do not include organisms identified only to the genus level in the pest list, as the taxonomic unit for pests selected for evaluation beyond theConducting Pest Risk Assesment in PPQ Process 4: Creating the pest list and pest categorization

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-10 

### pest categorization stage is usually the species (ISPM No. 11: IPPC, 2004b). Instead, we list pests identi fied only to the genus level in the “Pests considered but not included on the pest list” s ection, and we prep are genus-level datasheets for those that have acti onable regulatory status and have a reasonable likelihood of being associ ated with the harvested commodity.
Developing the pest list and selecting pests for further analysis 

### Pest categorization continues by determin ing which of the pests identified as actionable have a reasonable likelihood of being associated with the harvested commodity. Pests that are associated wi th the specific plant part(s) to be imported and are likely to remain viable with the plant part(s) throughout the harvesting process are generally considered to have a reasonable likelihood of being associated with the harvested commodity. These pests are analyzed further in Process 7: Assessing th e likelihood of introductionon page 2-35 and/

or Process 8: Assessing potential consequences of introductionon page 2-50

. Some plant pests may be of concern but are not selected for further analysis for a variety of reasons, such as  The pest is not associated with the ha rvested plant part(s) or is associated with those parts at an earlier stage but not at harvest.  The pest is mobile and will be eliminated while commodity is harvested.  The commodity is a conditional host, and there is high certainty the conditions for non-host status are met, etc.
If no actionable pests are likely to be associated with the harvested commodity, the risk assessment stops here.
Organisms identified only to the genus level 

### Organisms identified only to the genus level are difficult to assess, because pertinent biological information (pes t status, hosts, distribution, behavior) usually differs sufficiently between sp ecies that a general conclusion for the genus is not possible. Also, if the genus in question is reported in the PRA area, we often cannot know if the unidentifie d species occurs in the PRA area and, consequently, whether or not it has actionable regulatory status for the PRA area. We therefore usually do not include organisms identified only to the genus level on the pest list, and we do not assess them using Process 7: Assessing the likeli hood of introductionor Process 8: Assessing potential consequences of introduction

. However, because genus-level organisms may still pose a risk to the PRA area, it is not justifiable to simply ignore th em. Instead, we usually address them by following Procedure 4-5: Handling organisms identified only to genus level

. According to this procedure, unless there is a PPQ policy decision to the contrary, if the genus is not present in the PRA area, the U.S. regulatory statusConducting Pest Risk Assesment in PPQ Process 4: Creating the pest list and pest categorization

2-11 Guidelines for Plant Pest Risk Assessment ofImported Fruit & Vegetable Commodities 08/2012-1 

### of the “ Genus sp.” organism is “actionable,” wh ereas if the genus is present in the PRA area, the status is either “ non-actionable” or “undetermined.” For any

“ Genussp.” organisms with actionable regul atory status that could be on the harvested commodity plant part(s), we prepare a genus-level datasheet to be used by risk managers as a basis for determining if measures beyond those intended to mitigate fully identified pests are warranted. Often, however, the development of detailed as sessments for known pests th at inhabit a variety of ecological niches, such as internal fruit feeders or foliage pests, allows effective mitigation measur es to eliminate the known organisms as well as similar but incompletely identified organisms that inhabit the same niche.
It is important to note that there may be situations when it is appropriate not to follow Procedure 4-5: Handling organisms identified only to genus level . In particular, if there is sound eviden ce that the species in question (though identified only to genus) is different fr om any species of that genus known to occur in the PRA area (e.g., broader areas of establishment or host range), it should be listed as an “actionable” pe st. Also, there may be situations when a full analysis using Process 7: Assessing the likelihood of introductionand/or Process 8: Assessing potential consequences of introduction , instead of a genus-level datasheet, is warranted, such as when there is sufficient biological information on the unidentified organism to allow for proper analysis of its likelihood and consequences of introduction. If a full analysis is prepared, the pest should be included on the pest list.



## Procedure 4-1. Identifying potential pe sts for the pest list

Follow steps 1-6 to identify potential pests for the pest list. Step 1 Identify pests associated with the commodity plant an ywhere in the world. In this case, “association” includes any instance where you have evidence that links a pest to the commodity. Note that the actual host status (or strength of the association) will be evaluated in a subsequent procedure. Go to Step 2

. Step 2 Determine whether the pests identified in Step 1 are found in the exporting area. Go to Step 3

. Step 3 For organisms identified only to the genus level, go to Procedure 4-5: Handling organisms identified only to genus level

. For organisms identified to the species level or lower (e.g., biotypes, strains, race), go to Step 4

.Conducting Pest Risk Assesment in PPQ Process 4: Creating the pest list and pest categorization

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-12 

## Procedure 4-2. Optional: Determining whet her a pest is actionable

This procedure applies to pests identifi ed to the species level or lower. For organisms identified only to the genus level, continue to Procedure 4-5: Handling organisms identified only to genus level . This procedure is applicable for most pests, but in some cases, youmay need to consult other sources to determine whether a pest is actionable. It is not necessary, or in some cases appropriate, to use this procedure in instances where the PPQ policy for the pest is already know n (e.g., armored scales, which are nonreportable on commodities for consumption; some citrus pathogens where fruit is not a pathway for introduction, etc.). Treat pests listed as “reportable” in PestID as actionable, unless a specific no te in PestID or other PPQ port policy indicates otherwise. It also may be usef ul to consult previous PRAs in which the pest is listed, check domestic Emergency Action Notifications (EANs) for any evidence of domestic regulation, or seek information from DEEP (Deregulation Evaluation for Established Pests) or NPAG (New Pest Advisory Group) to clarify pest status. Step 4 Determine whether each pest is actionable at U.S. ports of entry on commod ities for consumption. Actionable pests include quarantine pests, regula ted non-quarantine pests, pests considered for or under official control, and pests that requir e evaluation for regulatory action. Go to Step 5

. Procedure 4-2: Optional: Determining whether a pest is actionable may be useful in determining whether a pest is actionable, but in some cases, you may need to consult other sources to make a determination. Step 5 Place pests with a non-actionable regulatory status in a separate table in an appendix to the risk assessment (PRA Template: Appendix A). You should provide supporting references in this appendix, including PPQ policy on non-actionable status, if relevant. See the PRA Template for more details. For actionable pests associated with the commodity and found in the export area, go to Procedure 4-3: Determining whether to include an actionable pest on the list

. 

## Procedure 4-1. Identifying potential pe sts for the pest list

Follow steps 1-6 to identify potential pests for the pest list.

Follow the steps of this procedure to determine whether a pest is actionable.

IF THEN Step 1 The pest’s genus is listed in PestID. Go to Step 2

. The pest’s genus i s not listed in PestID. Go to Step 6

. Step 2 The entire genus (i.e., “ Genus spp.”) is listed as “non-reportable.” The pest is non-actionable. Refer back to Step 5 of Procedure 4-1: Identifying potential pests for the pest list

. The entire genus (i.e., “ Genus spp.”) is not listed as “non-reportable.” Go to Step 3

.Conducting Pest Risk Assesment in PPQ Process 4: Creating the pest list and pest categorization

2-13 Guidelines for Plant Pest Risk Assessment ofImported Fruit & Vegetable Commodities 08/2012-1

Step 3 The pest species (or sub-species, if applicable) is listed in PestID. Go to Step 4

.
The pest species (or sub-species, if applicable) is not listed in PestID. Go to Step 6

.
Step 4 The pest is listed as “non-reportable” (either for all commodities or for commodities for consumption). The pest is non-actionable. Refer back to Step 5 of Procedure 4-1: Identifying potential pests for the pest list

. The pest is not listed as “non-reportable.” Go to Step 5

. Step 5 The pest is listed as “reportable” (either for all commodities or for commodities for consumption). Assume the pest is actionable. Continue to Procedure 4-3: Determining whether to include an actionable pest on the list

. The pest is not listed as “reportable.” Seek further guidance from National Identification Services or another regulatory expert. Step 6 There is evidence that the pest is present in the PRA area. Go to Step 7

.

There is no evidence that the pest is present in the PRA area. Assume the pest is actionable. Continue to Procedure 4-3: Determining whether to include an actionable pest on the list

. Step 7 There is a PPQ program or restriction policyin place for the pest--for example, the pest is under PPQ official control. Assume the pest is actionable. Continue to Procedure 4-3: Determining whether to include an actionable pest on the list

. There is not a PPQ program or restriction policy in place for the pest. Assume the pest is non-actionable. Refer back to Step 5 of Procedure 4-1: Identifying potential pests for the pest list

. Follow the steps of this procedure to determine whether a pest is actionable.

IF THEN



## Procedure 4-3. Determining whether to include an actionable pest on the list

Follow the steps of this procedure to determine whether to include an actionable pest on the list.

IF THEN Step 1 The available evidence indicates that the pest isassociated with the commodity plant species (anywhere in the world). Go to Step 2

.

The available evidence does not indicate that the pest is associated with the commodity. Do not include the pest on the pest list. Explain your rationale in the “Pests considered but notincluded on the pest list” section of the risk assessment. Step 2 The available evidence indicates the pest occurs in the export area. Go to Step 3

.

The available evidence does not indicate the pest
occurs in the export area. Do not include the pest on the pest list. Explain your rationale in the “Pests considered but notincluded on the pest list” section of the risk assessment.Conducting Pest Risk Assesment in PPQ Process 4: Creating the pest list and pest categorization

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-14

Step 3 The commodity plant species is a Type 1 host (natural host) for the pest, based on the pest’s association with the host species in any country of the world. Include the pest on the pest list. Continue to Procedure 4-4: Completing the pest list table

.

The commodity plant species is a Type 2 host (conditional host) for the pest, based on the pest’s association with the host s pecies in any country of the world. Include the pest on the pest list. Continue to Procedure 4-4: Completing the pest list table

.

The commodity plant species is a Type 3 host (natural non-host) for the pest, based on the pest’s association with the host s pecies in any country of the world. Do not include the pest on the pest list. Explain your rationale in the “Pests considered but not included on the pest list” se ction of the risk assessment. The commodity plant species is a Type 4 host (fomite) for the pest, based on the pest’s association with the host species in any country of the world. Include the pest on the pest list if there is clearevidence that the commodity is a common pathway for movement of the pest. Explain your rationale in the “Remarks” section of the pest list or inthe “Notes on pests identified in the pest list” section. Continue to Procedure 4-4: Completing the pest list table

. Otherwise, do not include the pest on the pest list. Explain your rationale in the “Pests considered but not included on the pest list” section of the risk assessment. 

## Procedure 4-3. Determining whether to include an actionable pest on the list

Follow the steps of this procedure to determine whether to include an actionable pest on the list.

IF THENConducting Pest Risk Assesment in PPQ Process 4: Creating the pest list and pest categorization

2-15 Guidelines for Plant Pest Risk Assessment ofImported Fruit & Vegetable Commodities 08/2012-1 

## Procedure 4-4. Completing the pest list table

For each step in this procedure, docum ent supporting information in the pest list or in the body of the ri sk assessment. Where appli cable, indicate sources of uncertainty, but do not use uncertainty codes. Be specific and clearly link appropriate evidence to relevant citation(s) . If you have text that is too long to reasonably fit in this pest list table, put this text in section 2.3 “Notes on pests identified in the pest list ” of the PRA Template and st ate in the pest list table “see additional discussion below in section 2.3.”
The pest list should be presented using the format shown in Table 2-1

. Arthropods should be listedalphabetically by order and then family. Pathogens should be divided by type. They shoul d be listed after the arthropods and proceed as follows: 1) Nematodes, 2) Fungi and Chromistans, 3) Bacteria and Phytoplasmas, 4) Viruses and Viroids, and 5) Pathogens of Unknown Etiology (biotic factors only). Other non-traditional entries, such as algae or protozoans, are to be listed in categories of their own as well. Pathogens should be listed alphabetically under each type (“type ” meaning: nematodes, etc.). Organization like the arthropods (separ ated by order and family) is not an efficient or stable way to present the pathogens due to the continuous revisions in pathogen taxonomy. These revisions are based on new evidence, and, with the growing application of molecular tools for identification, additional revisions are anticipated.

Follow the steps of this procedure to complete the pest list table. Step 1 Fill out each column on the pest list as follows, then go to Step 2

. Pest name:  List the current scientific name of the pest, including the authority.  List valid synonyms if needed to support information provided in the pest list.  In some cases, it might be appropriate to ident ify the organism below the species level (e.g., biotypes, race, or strains); consult the appropriat e authority for guidance. If listing an organism below the species level, clearly document the rationale for doing so. The rationale “should include evidence demonstrating that factors such as differences in virulence, host range or vector relationships are significant enough to affect phytosanitary status” (ISPM No. 11: IPPC, 2004b).  If only a common name is known, list it as such and incorporate the uncertainty level associated with a common name. Evidence of presence in export area:  Identify the evidence t hat the pest is found in the export area.  Describe uncertainty regarding distribution and, if relevant, regulatory status in the exporting country (e.g., limited distributi on and under official control).Conducting Pest Risk Assesment in PPQ Process 4: Creating the pest list and pest categorization

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-16 Host status:  State the host status of the commodi ty plant species for the pest (see Supplement 3: Host Status on page 3-10 ).  Base your conclusions on evidence of the pest’s association with the imported plant species in any country of the world.  If the commodity plant species is a Type 2 (conditional) host for the pest, provide information on the specific conditions under which it is a host and provide an explanation of the evidence and your uncertainty. If strong evidence indicates t he commodity is a Type 2b host (i.e., non-host), still include the pest on the pest list, and incl ude information regarding non-host status under “On harvested plant part(s)?”.  If the commodity is a Type 4 host (fomite), pr ovide evidence that the commodity is a common pathway for movement of the pest. Plant part(s) association:  Identify the part or parts of th e plant with which the pest is physically associated. Ideally, evidence should refer to the actual plant species to be imported and the ac tual pest species under analysis. However, in some cases, we may extrap olate from evidence referring to other plant species or closely related pest species. In thes e cases, provide information on your logic, assumptions for extrapolation, and uncertainty. On harvested plant part(s)?:  Indicate if the pest has a reasonable likelihood of being on and remaining with the plant part(s), in viable form, throughout the harvesting process. Consider all plant parts present after harvest but prior to post-harvest processing. Do not cons ider post-harvest practi ces, such as washing, dipping, etc., at this step even when they are routine.  Answer “Yes” or “No” and, if appropriate, cite and/or discuss evidence for your decision. Note: “Yes” indicates simply that the pest has a reas onable likelihood of being associated with the harvested commodity; the level of pest prevalenc e on the harvested commodity (low, medium, or high) is qualitatively assessed in Risk Element A1: Pest preval ence on the harvested plant part(s) as part of Process 7: Assessing the likelihood of introduction

.  Answer yes if:  The commodity plant species is a Type 1 hos t (natural host) for the pest, and the pest is reasonably likely to be associated with the commodity plant part(s) to be imported following harvesting from the field and prior to any post-harvest processing.  The commodity plant species is a Type 2 host (conditional host) for the pest, and conditions in the exporting area are such t hat there is a reasonable likelihood that the pest will be associated with the commodityplant part(s) to be imported following harvesting from the field and prior to any post-harvest processing.  Answer no if:  Characteristics of the pest, commodity, or harvesting process are such that it is unlikely the pest will be on the commodity after it is harvested.  The commodity plant species is a Type 2 host (conditional host) for the pest, and there is a reasonably high level of certai nty that the conditions for non-host status(Type 2b host) are met (e.g., specific varieties used for export known to be a nonhost, specific timing of harvest, only evid ence of host association under experimental conditions), and the status is supported by sufficient evidence. Keep the pest in the pest list table, and explain the conditions and evidence for the Type 2b status. Those pests for which the answer was yes, continue to Process 5: Collecting information and defining the endangered area on page 2-22

. If there are no pests for which the answer is yes, the risk assessment stops here. Follow the steps of this procedure to complete the pest list table.Conducting Pest Risk Assesment in PPQ Process 4: Creating the pest list and pest categorization

2-17 Guidelines for Plant Pest Risk Assessment ofImported Fruit & Vegetable Commodities 08/2012-1 Remarks: Use this section for information pertinent to the pe st list, but that does not fall under the previous columns. For example:  For pests that have a limited distribution in the United States but are included on the pest listbecause they are actionable pests: list the pest’s distribution in the PRA area and provide references, including PestID or agency correspondence.  Overarching assumptions and/or uncertainty. Step 2 Summarize the following information in sub-secti ons placed after the pest list table in the risk assessment:  “Notes on pests identified in the pest list”: Summarize information that is too lengthy to fit in the main pest list table. This sub-section can also include a summary of actionable pests not selected for further analysis, incl uding the justification for why t hey were not selected (e.g., the organism is not likely to be associated with the harvested plant part(s), the commodity meets the criteria for a Type 2b host for a pest, exis ting PPQ policy does not require analysis of those pests).  “Pests selected for further analysis”: List those pests on the pest list for which the answer to “On harvested plant part(s)?” is “Yes”. If you have completed your pest list, continue to Process 5: Collecting information and defining the endangered
area on page 2-22

. Follow the steps of this procedure to complete the pest list table.

Table 2-1. Actionable pests reported on [species name of plantto be imported] (in any country) and present in [export area] (on any host).Pest name Evidence of presence in the export
area Host status Plant part(s) association On the harvested plant part(s)? Remarks

Genus species Authority REFDescribe any uncertainty regarding distribution and, if relevant, regulatorystatus in the exporting country (REF) Type 1, 2, or 4 (REF) If applicable, provide brief justification for judgments and conclusions (REF) For Type 4 hosts, provideadditional justification for inclusion on pest list (REF) Indicate the part(s) of the plant with which the pest is associated(i.e., fruit, flowers, stems, leaves, roots).
Consider association on the actual imported plant species
Describe uncertainty regarding plantpart association includingany extrapolations or assumptions (REF) Yes or No
Provide brief justification for judgments and conclusions (REF) If pest is present in the United States: “Present in [List States]” (REF) Optional: Include a brief explanation of any additional information youfeel is necessary to capture in the pest listConducting Pest Risk Assesment in PPQ Process 4: Creating the pest list and pest categorization

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-18 

## Procedure 4-5. Handling organisms identi fied only to genus level

Refer to the following notes wh en completing this procedure.  Note 1. An organism identified to the ge nus level should on ly be included in the risk assessment if it is reported simultaneously on the commodity and in the export area in the same reference [e.g., “Genus sp. attacks Commodity X in Country X (Anonymous, 2010)”].  Note 2. Treat pests listed as “reportable” in PestID as “actionable,” unless a specific note in PestID or other PPQ port policy indicates otherwise.  Note 3. There may be situations when it is appropriate not to follow this procedure (see Organisms identified only to the genus level on page 2-10 ). If this is the case, clearly document the evidence and associated uncertainty for this decision in the risk assessment.

Follow the steps in this procedure to determine how to handle organisms identified only to genus level.

IF THEN Step 1 The genus (i.e., “ Genus sp.”) is listed in PestID. Go to Step 2

.
The genus (i.e., “ Genus sp.”) is not listed in PestID. Go to Step 3

.
Step 2 The whole genus (i.e., “ Genus sp.”) is listed as “reportable” in PestID in the PRA area. The pest either has actionable or undetermined regulatory status. Go to Step 3

.
The whole genus (i.e., “ Genus sp.”) is listed as “non-reportable” in PestID in the PRA
area. The pest is non-actionable. Refer back to Step 5 of Procedure 4-1: Identifying potential pests for the pest list

.

Step 3 There is adequate evidence that the pest occurs on the commodity in the export area. Add the pest to Table 1 in the “Organisms identified only to genus level” section of the risk assessment. Go to Step 4

.

There is not adequate evidence that the pest occurs on the commodity in the export
area. Add the pest to the “Pests with weak evidence for association with the commodity or for presence in the export area” section of the risk assessment.

Step 4 Any species in the genus is present in the PRA area. In Table 1 of the “Organisms identif ied only to genus level” section of the risk assessment, indicate that the genus is present in the PRA area and that the regulatory status is undetermined. Go to Step 5

. The genus is not present in the PRA area. In Table 1 of the “Organisms identif ied only to genus level” section of the risk assessment, indicate that the genus is not present in the PRA area and that the regulatory status is actionable. Go to Step 5

. Step 5 The pest could be associated with the harvested commodity plant parts. In Table 1 of the “Organisms identif ied only to genus level” section of the risk assessment, indicate that the pest could be associated the harvested plant parts. Go to Step 6

.Conducting Pest Risk Assesment in PPQ Process 4: Creating the pest list and pest categorization

2-19 Guidelines for Plant Pest Risk Assessment ofImported Fruit & Vegetable Commodities 08/2012-1 The pest could not be associated with the harvested commodity plant parts. In Table 1 of the “Organisms identif ied only to genus level” sectionof the risk assessment, indicate that the pest could not be associated with the harvested plant parts. Step 6 The pest has undetermined regulatory status

. In the risk mitigation notes document, state that the level of risk of the congeners (if any are to be analyzed in the risk assessment) may or may not be similar to that of the organism in question, and that in general, there is high uncertainty regarding efficacy of risk mitigation measures when applied to organisms identified only to the genus level. The pest has actionable status

. For each pest, create a genus-level datasheet. (Note: Do not create a datasheet for pests with undete rmined regulatory status). The datasheet should include the following primary elements:  absence of the genus in the PR A area and regulatory status of some species belonging to it (if information is available).  distribution of species from the genus in the world and potential for establishment in PRA area.  known host range (plant species and families) of different species within this genus.  biology contributing to dispersal (fecundity, number of generations, ability for active dispersal on its own or through human activities) and possibility of spread in PRA area.  potential for economic and environmental consequences in the PRA area. The following factors should be considered when assessing significance of the genus.  previous history of successful establishment in new areas.  phytopathogenic or phytophagous characteristics.  observations of causing injury to plants, beneficial organisms, etc.  being reported as pests.  ability to act as a vector for known pests.  adverse effects on non-target organisms beneficial to plants (such as pollinators or predators of plant pests).  interception records. Include the genus level datasheet as an appendix to the main riskassessment document. Summarize the information from the datasheet after Table 1 in section 2.1.3. “Organisms identified only to the genus level” of the risk assessment. In the risk mitigation notes document, state that the level of risk of the congeners (if any are analyzed in the risk assessment) may or may not be similar to that of the organism in question, and that in general there is high uncertainty regarding efficacy of risk mitigation measures when applied to organisms identified only to the genus level.
Continue to Process 5: Collecting information and defining the endangered area on page 2-22

. Follow the steps in this procedure to determine how to handle organisms identified only to genus level.

IF THENConducting Pest Risk Assesment in PPQ Processes in PPQ commodity import risk assessment

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-20 

# Stage 2: Pest Risk Assessment Stage 2 of pest risk analysis is co mposed of two distinct phases: pest categorization and risk assessment . In PPQ commodity import risk assessments, the firs t phase, pest categorization, begins as the pest list is built in Process 4: Creating the pest list and pest categorizationand continues in Process 5: Collecting informati on and defining the endangered areawhen we define the area endangered by the pest. The second phase, risk assessment, is the heart of Stage 2 and involves analyzing biological and economic information about the pests selected for further analysis in order to estimate their likelihood of being introduced into the PRA area (via the commodity) and identifying the potential economic and environmental impacts that would result from their introduction. 

## Processes in PPQ commodity import risk assessment In PPQ, pest risk assessment is divided into five processes:
 Process 5: Collecting informati on and defining the endangered area  Process 6: Assessing uncertainty for risk elements  Process 7: Assessing the likelihood of introduction  Process 8: Assessing potential consequences of introduction  Process 9: Summarizing the final risk ratings and uncertainty



## Risk elements evalua ted in PPQ commodity import risk assessment The likelihood that a pest will be introduced into the PRA area via the commodity is analyzed in Process 7: Assessing th e likelihood of introduction

. By definition (ISPM No. 5: IPPC, 2012) , this likelihood includes both the likelihood of the pest entry in the PRA area and the likelihood of its establishment in the PRA area upon en try. We determine the likelihood of introduction by evaluating the following risk elements (described in detail in Process 7). NOTE
Pest risk assessment is not linear; althou gh the processes of Stage 2 are numbered and described individually for convenienc e, they are not necessarily completedsequentially. Each process provides the framework and specific instructions for conducting various individual aspects of co mmodity import risk assessment, but analysts have flexibility in approaching each process and determining the best order in which to complete the assessment.Conducting Pest Risk Assesment in PPQ Risk elements evaluated in PPQ commodity import risk assessment

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### The potential impacts of a pest introduc tion in the PRA area are evaluated in Process 8: Assessing potential consequences of introduction . Once a pest has entered the PRA area, it must be able to establish and subsequently spread in order for there to be consequences. The consequences of introduction are determined by evaluating the following risk elements (described in detail in Process 8).

Risk Element A: Likelihood of entry  Risk Element A1: Pest prevalence on the harvested plant part(s)  Risk Element A2: Likelihood of surviving post-harvest processing before shipment  Risk Element A3: Likelihood of surviving trans port and storage condit ions of the consignment Determining the likelihood of establishment (Risk Element B)  Risk Element B1: Likelihood of coming into contact with host material in the endangered
area  Risk Element B2: Likelihood of arriving in the endangered area

Risk Element C: Determining the potential direct impacts  Risk Element C1: Damage potential in the endangered area  Risk Element C2: Spread potential Risk Element D: Determining potential trade impacts  Risk Element D1: Determining export markets at risk  Risk Element D2: Likelihood of trading pa rtners imposing additi onal phytosantiary requirements



### NOTE We evaluate spread potential as a part of the potential consequences of introduction because it relates to how quickly the pest will be able to cause full impacts in the PRA area.Conducting Pest Risk Assesment in PPQ Process 5: Collecting information and defining the endangered area

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## Process 5: Collecting information a nd defining the endangered area The purpose of this process is to gather and organize the biological, environmental, and economic informati on necessary for evaluating each of the risk elements and to determine the l ogical order in which they should be evaluated. Before beginning this proce ss, analysts should first determine whether an assessment or other standardtext (e.g., Pest Notes) has already been developed for the pest that could be relevant for the commodity pathway being assessed.
In general, assessment of the like lihood of entry involves evaluating the biology of the pest in term s of how the pest relates to the conditions of the pathway and the characteristics of th e commodity that were described in Process 3: Defining the pathway . Assessing the likelihood of establishment, spread, and the subsequent potential impacts of the pest in the PRA area involves evaluating the biology of the pestin relation to the suitability of conditions in the PRA area. Those c onditions include biotic factors (e.g., availability of host material, presenceor absence of natural enemies) and abiotic factors (e.g., temperature, s eason, humidity, rainfall, or other environmental conditions that affect th e ability of the pest to survive and reproduce).
Gathering information and identifying sources of uncertainty 

### The first part of Process 5 involves gathering the necessary information to complete Process 7: Assessing the likelihood of introductionand Process 8: Assessing potential cons equences of introduction . Analysts can and should consult many different sources of inform ation in this process, such as the scientific literature, databases, co mpendia, information provided by the exporting country, and subject matter experts. As much as possible, the information obtained should relate to th e specific pest and how it behaves on hosts and in environmental conditions s imilar to those present the PRA area. When such information is unavailable, an alysts may need to extrapolate from other related pests and situations. An alysts should explicitly note when collected data are based on extrapolations as it is an important factor in evaluating uncertainty. The type of information needed to complete Process 7: Assessing the likeli hood of introductionand Process 8: Assessing potential consequences of introductionincludes the following.

Information about the export area  prevalence of a pest or diseas e agent in the exporting area  geographic and environmental characteristics  standard industry practices and pr ocedures in the export area  surveillance system(s)  effectiveness of mitigation measures an treatm ents in the areas where (and if) controlledConducting Pest Risk Assesment in PPQ Process 5: Collecting information and defining the endangered area

2-23 Guidelines for Plant Pest Risk Assessment ofImported Fruit & Vegetable Commodities 08/2012-1  previous risk assessments (including those of foreign countries) of the commodity and related commodities from the same origin Information abou t the commodity  type or class of commodity  nature of raw material used to produce the commodity  intended use of the product  pest or disease agent survival in transit  interception data Pest-specific information  potential host range of the pest in the PRA area  symptoms expected to be caused by the pest on important potential hosts in the PRA area and plant parts affected  type and degree of damage caused  secondary damage that may occu r as a result of the pest  life history of the pest

 life stages (including duration)  reproductive strategies (s exual, parthenogenetic, etc.)  adaptive characteristics (dormancy, increased fecundity, number of generations, known expansion of host range, etc.)  climatic/environmental constraints of the pest

 temperature/humidity requirements  current geographic distribution  ease of detection/inspection  on commodity (e.g., size, ability to hide, si gns of damage, latency, distinctiveness of symptoms)  in the environment (e.g., meth ods of detection, including trapping mechanisms, signs of damage/presence)  ease of identification

 similarity to other species  methods of identification/diagnostics  ease of identification of various life stages  ease of removal of the pest from infested/ infected commodity during standard packinghouse practices (e.g., washing, brushing, waxing)  means of dispersal

 natural mobility of life stages (adult flight, larval silk ballooning, etc.)  vectors (and presence of vectors in the PRA area)  other mechanisms required for successful dispersal (wind, rain, soil, etc.)  other requirements necessary for dispersal (e .g., the availability of a particular phenological stage of the host)  prevention and control strategies used for the pest anywhere in the world

 field control  phytosanitary measures  possible effect of standard industry practices on survival of the pestConducting Pest Risk Assesment in PPQ Process 5: Collecting information and defining the endangered area

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-24 

### In addition to considering th e type of information available, analysts should be aware that the quality of the informati on will vary based on the source. Both the quality and applicability of availabl e information will impact the certainty of the resulting risk rating. Supplement 4: Evaluation of Evidenceon page 3-29 provides general guidance on how analys ts can relate both the quality and applicability of evidence to their level of uncertainty ( Process 6: Assessing uncertainty for risk elements on page 2-33 ). Analysts should identify gaps in knowledge and possible areas for future research in the mitigation notes ( Process 10: Risk mitigation notes on page 2-67 ).
When gathering information, analysts should keep in mind the scope of the analysis and the description of the pathway. In some cases it may be unnecessary to gather detailed informat ion on the biology of the pest or on the environmental conditions in the PRA area, pa rticularly when it is clear that the rating for a particular risk element is like ly to be negligible. For example, if the scope of the analysis ex plicitly includes evaluating a post-harvest treatment such as irradiation or fumigation that will, with a high degr ee of certainty, remove the pest from the pathway (or render it inviable), the likelihood of entry of the pest will be negligible and it would be unnecessary to gather additional informati on about this pest.  existing export protocol requirements where host commodities are currently enterable Information about the PRA area  After clearly defining the PRA area for the particular risk assessment (e.g., continental United States, all 50 U.S. stat es, U.S. territories only), analysts should consider information regarding  distribution of the commodity  availability of susceptible hos ts and/or competent vectors  geography and environment  control and production practices  presence of similar pestsConducting Pest Risk Assesment in PPQ Process 5: Collecting information and defining the endangered area

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### Determining the order of analysis 

### When the endangered area is defined and it is determined that at least some part of the PRA area could be enda ngered by the pest, an analyst should commence the risk assessment pha se. As previously mentioned, Process 7: Assessing the likeli hood of introductionand Process 8: Assessing potential consequences of introductioncan be conducted in either order. If it is determined that the risk associated wi th either the likelihood or consequences of introduction is Negligible, it may be unnecessary to complete the other processes. Further, within Process 7, the analysis of the individual risk elements can be completed in any order. In other words, in most cases, an analyst can start an assessment with any one of the following procedures.

In deciding the best order to proceed wi th the assessment, analysts should first consider whether the risk ratings for one or more of the elements are likely to be negligible. An element that is likely to have a negligible risk rating should generally be evaluated first, in order to avoid needless research and analysis. Next, analysts should consid er the availability, quality, and applicability of information necessary for evaluating each of the risk elements (see Supplement 4: Evaluation of Evidenceon page 3-29 ). As a general principle, it is more efficient to first evaluate the risk elements for which there is the greatest amount of reliable evidence available.
With experience, analysts will be able to decide which risk elements to evaluate first.
Defining the endangered area 

### While the PRA area is the area for which the risk assessment is intended, the endangered area is defined as the portion of the PRA area where ecological factors favor the establishment of the pe st and where the presence of the pest will result in economically important losses. In some cases, the area endangered by the pest may be as large as the entire PRA area, but in other cases, when the pest is restricted by climate or hosts, the endangered area may only constitute a small portion of the PRA area.
There are two important parts to determining the endangered area. First we identify the portion of the PRA area where th e organism is likely to be able to establish. Then, wedetermine whether the pest has the potential to damage economically important pl ants in that area.

Procedure 7-1: Assessing the likelihood of entry (Risk Element A) Procedure 7-2: Determining the likelihood of establishment (Risk Element B)  Risk Element B1: Likelihood of coming into contact with host material in the endangered
area OR  Risk Element B2: Likelihood of arriving in the endangered area Procedure 8-1: Determining the potential direct impacts (Risk Element C)Conducting Pest Risk Assesment in PPQ Process 5: Collecting information and defining the endangered area

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-26 

### Identifying the portion of the PRA area where the pest can actually survive and cause negative impacts is a crucial precursor to dete rmining the potential risk of the pest in terms of its likeli hood of establishmen t and associated consequences. Based on the biology of th e pest and the identified biotic and abiotic conditions of the PRA area, anal ysts determine the area endangered by the pest (i.e., the endangered area) by identifying the portion of the PRA area where the pest can likely establis h and cause economic ally important consequences. Important factors that in fluence where the organism can survive include abiotic factors such as temper atures (minimum/maximum), humidity, and rainfall, and biotic fact ors such as the availabilityof suitable host material. Host material suitable for survivalmight include uncultivated, unmanaged plants, or even weeds, that are not economically important. However, for the purposes of these Guidelines, we will be considering as pest hosts only economically important plants that occur in the areas of suitable climatic conditions. As a result, we assume that th e area potentially suitable for a pest establishment is the same as the endangered area.
In many cases, we do not have detailedinformation on the abiotic requirements of the pest or on the abiotic conditi ons of the PRA area. The global plant hardiness zone map developed by Magare y et al (2008) groups regions that have the same average annual extreme minimum temperature into distinct zones ( Figure 2-2 ), allowing for easy comparison and matching of the temperature suitability in the areas of the pest’s current distribution elsewhere in the world to that of the PRA area. Because temperature, particularly low winter temperature, is often a criticalfactor determini ng the geographical range of many organisms (especially ins ects) (Worner, 1998; Bale et al., 2002), the area endangered by a pest can often be described in terms of average minimum temperature zones by “plant hardiness zone matching.” It is important to note that when we use th is method to define the portion of the PRA area climatically suitable for pe st establishment, we are making two implicit assumptions: 1) that cold tolerance is the major limiting factor of the pest’s current distribution, and 2) that co ld tolerance is likely to be the major restriction in the PRA area.
If analysts have specific information th at can narrow this area or otherwise provide more precision, the endangere d area may be described by other relevant means, so long as the boundaries (such as states or counties) are clearly identified (see Procedure 5-2: Defining the endangered area ). In any case, regardless of how the endangered area of the pest is defined, it must have both a suitable climate and available hosts.Conducting Pest Risk Assesment in PPQ Process 5: Collecting information and defining the endangered area

2-27 Guidelines for Plant Pest Risk Assessment ofImported Fruit & Vegetable Commodities 08/2012-1 Figure 2-2. Temperature zones (aka “plant hardiness zones”) for defining the endangered area (Magarey et al., 2008).Conducting Pest Risk Assesment in PPQ Process 5: Collecting information and defining the endangered area

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-28 

## Procedure 5-1. Determining the order of analysis

Follow the steps below to determine the order of analysis.

IF THEN Step 1 An analysis or other standard text has already been developed for the pest that is relevant for the commodity pathway being assessed. (Check Pest Notes and/or the PRA library.) If appropriate, use the analysis in your assessment and continue to Process 9: Summarizing the final risk ratings and uncertaintyon page 2-63

. Otherwise, go to Step 2

. No analysis or other standard text has developed for the commodity pathway being assessed. Go to Step 2

.
Step 2 Based on the scoping call, the defined pathway explicitly includes treatments (such as irradiationor fumigation) that would likely lead to the pest having a negligible likelihood of entry. Continue to Procedure 7-1: Assessing the likelihood of entry (Risk Element A)

.

Based on the scoping call, the defined pathway does not include any treatments (such as irradiation or fumigation) that would likely lead to the pest having a negligible likelihood of entry. Go to Step 3

.

Step 3 Conduct a preliminary search for information on the pest (see Gathering information and identifying sources of uncertainty ). Consider the availability, quality, and applic ability of information necessary for evaluating each of the risk elements and then determine your order ofanalysis. As a general principle, it is more efficient to first evaluate the risk elements for which there is the greatest amount of reliable evidence available. In determining the order of analysis, keep in mind that the pestanalysis can stop if:  The Likelihood of Entry is rated Negligible.  There is no endangered area ( Procedure 5-2: Defining the endangered area ).  The pest is determined to be a non-threshold pest ( Process 8: Assessing potential consequences of introduction on page 2-50 )  Either Risk Element B1 or Risk Element B2 (under Likelihood of Establishment) is rated Negligible.Conducting Pest Risk Assesment in PPQ Process 5: Collecting information and defining the endangered area

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## Procedure 5-2. Defining the endangered area

NOTE This procedure is unnecessary when Risk Element A: Likelihood of entryis rated Negligible. It may also be unnecessary if the pest is highly unlikely to transfer from the commodity to a new host on its own (see Step 1 of Risk Element B1: Likelihood of coming into contact with host material in the endangered area ).

Determine the area endangered by the pest by following the steps in this procedure. In some cases, Step 1 and Step 2 may be combined (for example, if you use a model in Step 1 that considered both climate and host availability). Step 1 Using plant hardiness zone matching or another meth od, identify the portion of the PRA area that has climatic conditions suitable for the pest’s surv ival based on its current global geographic distribution and any biological characteristics that may lim it its ability to survive in the PRA area (such as temperature tolerance, humi dity requirements, etc.). If you determine that suitable environmental conditio ns do not exist in the PRA area, or exist in protected areas only (e.g. glasshouse s), state this in the risk assessment and conclude that the endangered area is Negligible. The assessment of the pest can stop at this point. Otherwise, proceed to Step 2

. Plant hardiness zone matching. In this method you will use the global plant hardiness zone map developed by Magarey et al. (2008) to match the plant hardiness zones where the pest currently is found to the corresponding zones in the PRA area. 1. Determine the current distribution of the pest through the world. 2. Using the map developed by Magarey et al. (2 008), identify the plant hardiness zones in which the pest is currently distributed. If a pest is re corded in a country with several plant hardiness zones and there are no data on sp ecific areas of its distribution, consider all hardiness zones in that country (if it is reasonable to do so). 3. Identify the corresponding plant hardiness zones in the PRA area. Other methods. If you have specific information that c an identify the climate requirements with more precision than hardiness zones, you may use this information to either refine the boundaries of the temperature zones identified using plant hardiness zone matching, or you can use another method of climate matching (e.g ., NAPPFAST model, degree-day model, precipitat ion analysis, etc.). Regardless of the method yo u use, you must clearly identi fy the geographic area you have determined is likely to be climatically suitable for the pest by either providing a map or by clearly describing the boundaries of the area. Step 2 Determine the distribution of Type 1 hosts of the pes t in the portion of the PRA area identified in Step 1 (i.e., in the area where climatic conditions are suitable for the pest’s establishment). Determine the distribution of Type 2 hosts in this ar ea if there is a reasonably high level of certainty that the conditions for host status would be met there. If you determine that no suitable host material is found in the portion of the PRA area identified in Step 1 (except in protected areas, such as glasshou ses), state this in the risk assessment and conclude that the endangered area for the pest is Neg ligible. The assessment of the pest can stop at this point. Otherwise, go to Step 3

.Conducting Pest Risk Assesment in PPQ Process 5: Collecting information and defining the endangered area

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-30

Step 3 Determine if any of the hosts present in the area of concern (identified in step 2) are of economic importance. As defined by ISPM No. 11, Suppl ement 2 (IPPC, 2004b), “economically” important hosts refers to both commercial and no n-market (environmental) plants such as  agricultural crops  horticultural crops, ornamentals, nursery plants  timber  environmentally important non-commercial hosts such as threatened and endangered species, plants important to aesthetics of natural areas, ecologically important species, etc.  plant species with a particular social impo rtance, such as those to Native Americans If you determine that none of the hosts plants identified in Step 2 are of economic importance, state this in the risk assessment and conclude that the endangered area for the pest is Negligible. The assessment of the pest can stop at this point. Otherwise, go to Step 4 on page 2-31

. Determine the area endangered by the pest by following the steps in this procedure. In some cases, Step 1 and Step 2 may be combined (for example, if you use a model in Step 1 that considered both climate and host availability).Conducting Pest Risk Assesment in PPQ Process 5: Collecting information and defining the endangered area

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Step 4 Based on the behavior and symptoms of the pest in the areas where it is currentlydistributed, determine whether the pest has the potential to impa ct the specific plant hos t species identified in step 3 by answering the questions below. Where the symptoms and/or the degree of damage c aused by the pest vary throughout the pest’s distribution, you should place emphasis on the symptoms and damage the pest causes in regions most climatically similar to th e area of concern (identified in Step 1 ) and on plant identified in Step 3

. 1. In its current area of distribut ion, is the organism a known pest (o r vector of a pest) of any of the hosts identified in Step 3 ?  For example:

 Has the organism been described in the literature as a pest on one or more of the hosts identified in Step 3 ?  Do control programs for the pest exist on one or more hosts identified in Step 3 ?  Has the pest been documented to ca use reductions in plant densit y, or impact ecological fitness of at least one of the non -commercial hosts identified in Step 3 (anywhere in the world)?  Has the pest been documented to cause yield losses in commercial production of at least one host identified in Step 3 ? Consider both pre-harvest and post-harvest losses (losses due to unmarketable commodity). 2. Based on the type of damage ca used by the pest in its current di stribution, could the pest (acting by itself or as a vector) cause damage to the hosts identified in Step 3 ?  For example:

 Is the type of damage or symptoms caused by the pest likely to result in pre-harvest losses of any commercially produced hosts identified in Step 3 (e.g., plant mortality, premature fruit drop, prevention of fruit set, dieback)?  Is the type of damage or symptoms caused bythe pest on any of the commercially produced commodities identified in Step 3 likely to result in post-harvest production losses (due to unmarketable commodity)?  Is the type of damage or symptoms caused bythe pest on any of the commercially produced commodities identified in Step 3 likely to result revenue losses resulting from a reduction in the value of the commodity (e.g., yellow/damaged leaves on a horticulture plant resulting in a lower market price; damaged fruit divert ed from fresh market to juice market)?  Is the type of damage caused by the pest likely to impact any of the envir onmentally or socially important plants identified in Step 3 ? If you answered yes to either Question 1 or 2 , go to Step 5

. If neither of the questions above could be answered yes , state in the risk assessment that the pest potential on economic hosts at risk is Neglig ible and conclude that the endangered area for the pest is Negligible. The assessment of the pest can stop at this point. Determine the area endangered by the pest by following the steps in this procedure. In some cases, Step 1 and Step 2 may be combined (for example, if you use a model in Step 1 that considered both climate and host availability).Conducting Pest Risk Assesment in PPQ Process 5: Collecting information and defining the endangered area

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Step 5 Describe the endangered area. In most cases, you can describe the endangered area in terms of the Magarey et al. (2008) plant hardiness zones. As mentioned above, these zones provide a convenient method for bounding the endangered area because they divide the PRA area in to distinct regions that have similar climates (in terms of average minimum wint er temperatures) and, in manycases, hosts. To define the endangered area, simply identify the zones that have both suitab le climate (as identified in Step 1 ) and available hosts (as identified in Step 2 ). In the risk assessment, state that the endangered area of the pest is considered to be within the identi fied zones, and explain your rationale and any uncertainty. If you have used methods in Step 1 and Step 2 that more precisely identifythe area of concern, you may define the endangered area in other terms; howe ver, you must clearly describe the boundaries of this area (e.g., by state or county) and provid e a map, if applicable. The identified area must have both suitable climate ( Step 1 ) and economically important hosts at risk ( Step 3 and Step 4 ). In the risk assessment, be sure to clearly explain your rationale and any uncertainty. Determine the area endangered by the pest by following the steps in this procedure. In some cases, Step 1 and Step 2 may be combined (for example, if you use a model in Step 1 that considered both climate and host availability).Conducting Pest Risk Assessment in PPQ Process 6: Assessing unce rtainty for risk elements

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## Process 6: Assessing uncert ainty for risk elements Separating the uncertainty th at arises due to lack of knowledge from the ratings of risk elements is important; ratings are made based only on the available evidence, not the uncertainty associated with the evidence. For instance, a given risk element should not be rated higher if there is a lot of uncertainty; rather, the rating should be assigned ba sed on available evidence and the high level of uncertainty should be noted. At the same time, werecognize that a given risk element may be assigned a rating that may more or less accurately reflect the actual probability associatedwith that risk element, depending on the level of uncertainty. Higher levels of uncertainty could mean a given rating may be over- or under-estimating probabili ty by one or more levels (e.g., a low rating with high uncertainty would truly be medium or high if we had more evidence on which to base our judgment).

For some risk elements and where inform ation is available, variability might be included in the rating; such situati ons should be documente d in the text of the analysis. In cases with a high degree of variability, the analyst will typically make a conservative judgment resulting in a higher risk rating. This underscores the importance of describi ng uncertainty—including sources and magnitude—while at the same time maintaining judgments that are based on available evidence.
We assess the uncertainty associated with each risk rating under likelihood of introduction ( Process 7: Assessing the likelihood of introduction ) and potential consequences of introduction ( Process 8: Assessing poten tial consequences of introduction ). Procedure 6-1: Assessing uncerta inty for each risk element is a guide for assigning uncertainty ratings to each risk rating based on available evidence (modified after Andrews et al., 2004). Where appropriate, analysts should provide written explan ations about the level of certainty associated with each rating. Gaps inknowledge should be specifi cally discussed, and possible areas of future research should be identified, as appropriate.
Analysts should consult Supplement 4: Evaluation of Evidence on page 3-29 when assessing and assigning ratings of uncertainty. The supplement provides guidance on relating both the quality and qu antity of evidence to the level of uncertainty.Conducting Pest Risk Assessment in PPQ Process 6: Assessing unce rtainty for risk elements

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-34 

## Procedure 6-1. Assessing uncertainty f or each risk element

For each risk rating, assign an uncertainty rati ng based on the guidance in this procedure. Uncertainty rating Description Certain (C) Additional or better information is ve ry unlikely to change the rating. This rating requires that:  The risk rating is based on well-documented evidence (e.g., original research paper published in peer reviewed journal, or a survey conducted by an NPPO with an approved methodology).  Area- or species-specific data are available.  Scientific consensus exists on metho dological approach, or our agency has much experience with the pest. Moderately certain (MC) Additional or better information probably will not change rating. Example justifications for this rating:  Published articles or other documentati on consists of review article of several original research studies.  Research or survey results are available but without detailed methodology. Moderately uncertain (MU) Additional or better information may or may not change rating. Example justifications for this rating:  Some area- or species-specific data are used, but most of the data were approximated or extrapolated from sim ilar situations (i.e., research conducted in the areas of comparable clim ate, on a related host, or with a congeneric pest species). Uncertain (U) Reliable information is not available. Example justifications for this rating:  The risk rating is based on poorly documented methodology and results.  No area- or pest-specific data are av ailable and no close approximations were used.  No reliable identification of the organism is available.  The pest biology, association with the host, or field prevalence are unknown.Conducting Pest Risk Assessment in PPQ Process 7: Assessing the likelihood of introduction

2-35 Guidelines for Plant Pest Risk Assessment ofImported Fruit & Vegetable Commodities 08/2012-1 

## Process 7: Assess ing the likelihood of introduction We assess the likelihood of introduction by assigning High, Medium, Low, or Negligible ratings, as determined belo w in Risk Elements A and B. We note that in these risk elements we define “surviving” to mean avoiding mortality, remaining reproductively viable, and re maining with the commodity; this can include pests and pathogens that can remain dormant, live endophytically or remain latent in the host without show ing signs or symptoms of infection.

In Risk Element A: Likelihood of entry , we assess the likelihood of entry of the pest into the PRA area. We assess this likelihood by determining a baseline risk rating [ Risk Element A1: Pest prevalenceon the harvested plant part(s) ] based on the likely pest prevalence or popul ation on the harvested commodity. From that point, we determine if the pest pr evalence will increase, decrease, or remain the same as the pest moves along the pathway. We specifically examine the likelihood that post-harvest processing before shipment ( Risk Element A2: Likelihood of surviving post-harv est processing before shipment ), as well as transport and shipping conditi ons will affect pest pr evalence and thus entry potential ( Risk Element A3: Likelihood of surviving transport and storage conditions of the consignment ). We note that, in some cases, pest prevalence may increase after harvest. If we have evid ence that this is likely to occur, we will specifically address this in the ri sk elements below. Additionally, although the volume of commodity entering the PRA area also impacts the entry potential of each pest, unl ess otherwise noted, we assume that the volume of commodity entering the country will be of a sufficient amount that entry and establishment is probable.

In Risk Element B: Likeli hood of establishment , we assess the likelihood that the pest will establish in the PRA area upon entry. Specific sub-elements include Risk Element B1: Likelihood of coming into contact with host material in the endangered area and Risk Element B2: Likelihood of arriving in the endangered area

. We combine the likelihoods of entry an d establishment to give an overall likelihood of introduction. We define the different categories of the overall likelihood of introduction as follows:  High. Pest introduction is highly likely to occur.  Medium . Pest introduction can occur, butfor that to happen the exact combination of required events described needs to occur.  Low . Pest introduction is unlikely to oc cur because one or more of the required events is unlikely to happen, or the full combination of required events is unlikely to align properly in time and space.Conducting Pest Risk Assessment in PPQ Process 7: Assessing the likelihood of introduction

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-36 

###  Negligible . Pest introduction is highly unlikely to occur given the exact combination of events required for successful introduction.



## Procedure 7-1. Assessing the like lihood of entry (Risk Element A)

Risk Element A: Likelihood of entry Risk Element A1: Pest prevalence on the harvested plant part(s). 

### Provide a qualitative rating for the size of the pest population that may beassociated with the harvested plant part(s). This will be the baseline rating for likelihood of entry. For the baseline risk level, assu me that the commodity was not subjected to any post-harvest treatment s, including those that are usually associated with good industry practices, such as washing for mango. Determine the baseline risk ranking by deciding which of the criteria in Risk Element A1: Pest prevalence on the harv ested plant part(s) best apply to the pest you are analyzing. Rate your uncertainty ( Process 6: Assessing uncertainty for risk elements ) and provide a narrative e xplanation for your decision. NOTEThe risk factors comprising the model for likelihood of introduction are interdependent and therefore the model is multiplicativ e rather than additive. Therefore, if anyof the risk ratings in this section are Negligible for a certain pest, the overall likelihood of introduction for that pest becomes Negligible and the assessment for may stop.



### NOTE A Negligible rating is not possible for Risk Element A1: Pest prevalence on the harvested plant part(s) because only pests associated with the harvested commodity were selected for further analysis in Process 4: Creating the pest list and pest categorization . If a pest-free area was being considered as a part of the defined pathway,that pest would already have been removed from the pathway in the previous process.



### NOTE Type 2b hosts (conditional non-hosts) wo uld have been included in the pest list ( Procedure 4-3: Determining whether to include an actionable pest on the list ) but not subject to further analysis if there was sufficient evidence and a reasonable levelof certainty that the commodity met Type 2b host criteria (e.g., a non-host). Therefore, in this procedure, you should consider conditional hosts to be Type 2a hosts (that is, the commodity can serve as a ho st under specified conditions). Consult Supplement 3: Host Status on page 3-10 for more details on designating host status.Conducting Pest Risk Assessment in PPQ Process 7: Assessing the likelihood of introduction

2-37 Guidelines for Plant Pest Risk Assessment ofImported Fruit & Vegetable Commodities 08/2012-1 Risk Element A2: Likelihood of surviv ing post-harvest processing before shipment. 

### Assess the likelihood of the pestsurviving through post-harvest processing, packing, and preparing the co mmodity for shipping. For this risk element, consider the post- harvest practices defined fo r the pathway in Process 3 and how they affect the likelihood th at the pest will remain with the commodity. Do not give a separate rati ng for the likelihood that the pest will survive post-harvest processing before shipment. Rather, depending on the likelihood, you should adju st the rating from Risk Element A1: Pest prevalence on the harvested plant part(s) (the baseline risk rating) up or down as appropriate, or keep it the same.
Consider the following:  The ease of detection of infe sted/infected co mmodity during packinghouse practices described in Process 3: Defining the pathway

. Risk Element A1: Pest prevalence on the harvested plant part(s)

IF THEN Step 1 Any of the following statements apply:  Evidence indicates that this organism always has a low association with the harvested plant parts.  The export area is recognized as an area of low pest prevalence (ALPP) for the pest in question.  The commodity is a Type 2 host and the specific conditions required for it to serve as a host are unlikely to occur at any given time (e.g., for a Type 2a host, conditions generally are such that the pest can only rarely successfully attack the host, seasonality). The baseline risk rating (A1) is Low. Continue to Step 2

.

Any of the following conditions apply:  Effective standard industry practices exist in the field and are applied before commodity is harvested.  The commodity is not a preferred fe eding (infection) site for the pest (e.g., the pest is occasionally associ ated with fruit, bu t generally feeds only on leaves).  The commodity is a Type 2 host under specific environmental conditions, and those conditions occur sometimes but not constantly (e.g.,for a Type 2a host, the conditions are such that the pest may successfully attack or infect the commodity at least some of the time, seasonality). The baseline risk rating (A1) is Medium. Continue to Step 2

.

Both of the following statements apply:  The plant species to be imported is 1) a host and 2) the part(s) to be imported is a preferred feeding site of the pest. (For Type 2 hosts, the commodity is a Type 2a host underspecific environmental conditions, and those conditions frequently or always occur).  No standard industry field practices beyond minimal handling during harvest are being considered. The baseline risk rating (A1) is High. Continue to Step 2

.Conducting Pest Risk Assessment in PPQ Process 7: Assessing the likelihood of introduction

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-38 

###  The ease of removal of the pest from infested/i nfected commodity during standard packinghouse practices , e.g., washing, brushing, waxing.  The quality standards and their possibl e effect on the pest’s association with the commodity.Conducting Pest Risk Assessment in PPQ Process 7: Assessing the likelihood of introduction

2-39 Guidelines for Plant Pest Risk Assessment ofImported Fruit & Vegetable Commodities 08/2012-1

Risk Element A2: Likelihood of surviving post-harvest processing before shipment

IF THEN Step 2 Evidence indicates that the entire pest population is highly likely to be killed or rendered inviable during processing (e.g., PPQ- approved irradiation treatment). The rating is Negligible. Stop the risk assessment for the pest here. Summarize your findings and uncertainty.
Continue to Process 9: Summarizing the final risk ratings and uncertaintyon page 2-63

. Evidence does not indicate that the entire pest population is highly likely to be killed or rendered inviable during processing. Go to Step 3

.

Determine which of the situations in Step 3 best applies to the pest you are analyzing. Provide your rating, rate your uncertainty, and provide a narrative explanation for your decision. Step 3 Reliable efficacy data or comparable evidence, provided by the NPPO of t he exporting country or acomparable source, indicate that processing measures are likely to significantly reduce pest prevalence in the commodity (e.g., surface pests eliminated during washing, pathogens mitigated by washing with bleach).Do not automatically assume the efficacy of measures. Evidence needs to be specific and credible,and should be provided by the NPPO of the exporting country or other comparable source. Decrease the baseline risk rating (A1) by one level.
A1 becomes A2
H M

M L

L Negl.*

*A change in the rating from Low to Negligible should be based on reliable evidence that the post-harvest processes described in the Process 3: Defining the pathway are highly likely to kill or render inviable the pest population remaining from the previous step. If this is the case, the risk assessment process can stop here. Continue to Process 9: Summarizing the final risk ratings and uncertainty

. The pest is neither elimi nated from the commodity nor does the population increase. In other words, you expect the pest prevalenc e in the commodity to remain more or less cons tant on the commodity through the post-harvest process. The baseline risk rating does not change. The rating for A2 stays the same as the rating for A1.

Either of the following apply:  Evidence indicates that the prevalence of the pest can significantly increase in the period after harvest and before shipping.  Safeguards for the commodity are absent, and this seems likely to lead to re-infestation (e.g., no insect-proof screens on field boxes or in the packinghouse). In other words, you expect the pest prevalence in thecommodity to increase during the post-harvest process. Increase the baseline risk rating (A2) by one level.
A1 becomes A2
H H

M H

L M

Continue to Risk Element A3: Likelihood of surviving transport and storage conditions of the consignment

.Conducting Pest Risk Assessment in PPQ Process 7: Assessing the likelihood of introduction

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-40 Risk Element A3: Likelihood of survivi ng transport and storage conditions of the consignment. 

### Here we assess the likelihood of the pest remaining with the commodity from packing through arrival. For this element, we consider the duration and conditions of transport and storage in the defined pathway, and the effects of these on pest survival. We also give the descri ption of uncertainty associated with this rating.
Examples of factors you should consider include:  Duration of the life cycle of the pest in relation to time in transport and standard shipping conditions. For example, if transport is by air, the risk is likely to be high for most of the organisms because of the short duration of transport.  Vulnerability of the life stages during transport or storage. Some conditions (combination of temperature and storage time) could be close to the limits of cold tolerance for certain life stages.  Standard industry practices and their pos sible effect on the survival of the pest, if any.

NOTE Do not give a sepa rate rating for Risk Element A3: Likelihood of surviving transport and storage conditions of the consignment . Rather, depending on this likelihood, adjust the rating from Risk Element A2: Likelihood of su rviving post-harvest processing before shipment up or down one level, or not at all, as appropriate.Conducting Pest Risk Assessment in PPQ Process 7: Assessing the likelihood of introduction

2-41 Guidelines for Plant Pest Risk Assessment ofImported Fruit & Vegetable Commodities 08/2012-1

Risk Element A3: Likelihood of surviving transport and storage conditions of the consignment

IF THEN Step 4 Either of the following apply:  Conditions in transit or storage are equivalent in duration and temperature to an approved APHIS treatment against the same pest on the same commodity.  Evidence indicates that the entire pest population is highly likely to be killed or rendered inviable during transportation or storage. The rating is Negligible. Stop the risk assessment for the pest here. Summarize your finding and uncertainty.
Continue to Process 9: Summarizing the final risk ratings and uncertaintyon page 2-63

.

Neither of the above apply. Go to Step 5

. Determine which of the situations in Step 5 best applies to your pest, provide your rating, rate your uncertainty, and provide a narrative explanation for your decision. Then go to Procedure 7-2: Determining the likelihood of establishment (Risk Element B)

. Step 5 Evidence indicates that the conditions of transport or storage in the defined pathway would significantly reduce the pest population with the commodity. Decrease the risk rating for A2 by one level.
A2 becomes A3
H M

M L

L Negl.*

*A change in the rating from Low to Negligible should be based on reliable evidence that the post-harvest processes described in the Process 3: Defining the pathwayare highly likely to kill or render inviable the pest population remaining from the previous step. If this is the case, the risk assessment process can stop here. Continue to Process 9: Summarizing the final risk rati ngs and uncertainty

. The transport and storage conditions in the defined pathway have no effect on the pest population. The risk rating does not change. The rating for A3 stays the same as the rating for A2. Either of the following apply:  Evidence indicates that the prevalence of the pest can significantly increase during shipping (specify conditions)  Safeguards for the commodity are absent and this can lead to re-infestation Decrease the risk rating for A2 by one level.
A2 becomes A3
H H

M H

L MConducting Pest Risk Assessment in PPQ Process 7: Assessing the likelihood of introduction

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-42 

## Procedure 7-2. Determining the likelihood of establishment (Risk Element B)

Risk Element B: Likelihood of establishment 

### In this risk element, we assess the pest opportunity for es tablishment based on availability of host and suitable climate. It consists of tw o independent risk elements, Risk Element B1: Likelihood of coming into contact with host material in the endangered area and Risk Element B2: Like lihood of arriving in the endangered area , which can be analyzed in either order. If the risk rating for either element is Negligible, the analys is of the pest can stop at that point.

Risk Element B1: Likelihood of coming in to contact with host material in the endangered area. 

### First, we assess how likely the pest is to come into contact with a suitable host. To do this, consider the following:
 The endangered area identified in Process 5: Collecting information and defining the endangered area

.  Distribution of hosts in the endangered area. If applicable, consider if the pest requires alternate hosts to completeits life cycle, and if those hosts are present in the endangered area (e.g., the devel opmental cycle of some aphids).  The pest life stage(s) present on the imported commodity and information relating the likelihood of it coming into contact wi th a host and attacking/ infecting it. For example:  known dispersal mechanisms (e.g., active or passive dispersal mode).  vectors needed for its dispersal and their presence in the endangered

area.  proportion of survivors within a cert ain time period after leaving the commodity.  ability to complete development and/or reproduce on the commodity before or after arrival in the endangered area.

NOTE It is essential to follow the order of steps when rating this risk element.Conducting Pest Risk Assessment in PPQ Process 7: Assessing the likelihood of introduction

2-43 Guidelines for Plant Pest Risk Assessment ofImported Fruit & Vegetable Commodities 08/2012-1

Risk Element B1: Likelihood of coming into contact with host material in the endangered area Use the following guidance to determine the risk rating for Risk Element B1. Provide your rating, rate your uncertainty, and provide a narrative explanation for your decision.

IF THEN Step 1 Any of the conditions listed below app ly to the pest situation you are assessing.  The phenological stage of available hosts in the endangered area is unsuitable for pest establishment during the importation season, and the pest cannot survive until the host becomes suitable.  A vector or other agent required fo r contact with the host to occur is absent in the endangered area or pr esent but cannot acquire or transmit the pest (i.e., does not feed on the discarded plant part).  The pest life stage present is highly unlikely to move on its own from the commodity to a new host and  is highly unlikely to develop into a dispersing life stage, OR  the dispersing life stage of the pest is very short-lived and very susceptible to different mortality factors (e.g., exposure to elements, natural enemies, etc.). The rating for Risk Element B1 is Negligible. Stop the risk assessment for the pest here. Summarize your finding and uncertainty.
Continue to Process 9: Summarizing the final risk ratings and uncertainty

.

None of the above conditions apply. Go to Step 2

. Step 2 Any of the conditions listed below app ly to the pest situation you are assessing.  Conditions necessary for the pest’s transmission to the host are seldom met (e.g., temp erature, moisture).  Few natural hosts exist in the endangered area. For example:

 very low host density in the stands or their populations are sparsely distributed through the endangered area.  hosts are tropical/subtropical plants only and not commercially produced.  pest has a restricted host range.  Vector or other dispersal agent is present (if required), but with low prevalence.  Dispersing life stage of the pest has lim ited ability to disperse naturally. The rating for Risk Element B1 is Low.

None of the above conditions apply. Go to Step 3

.Conducting Pest Risk Assessment in PPQ Process 7: Assessing the likelihood of introduction

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-44

Step 3 Given that the pest is capable of dispersing on its own or through a widely prevalent vector, any of the condition s listed below apply to the pest situation you are assessing.  Suitable hosts are widely established in only a limited portion of the endangered area (e.g. commercially-produced warm climate crops when the endangered area includes both temperate and warm climate areas).  Suitable hosts are not continuouslydistributed throughout the endangered area (e.g., botanical gardens).  The commodity may arrive in the endangered area at times when phenology of the host is not suitable.  The environmental requirements necessary for the pest’s successful transfer to and establishment on newhosts in the endangered area are met only under certain conditions (e .g., season, temperature, humidity, etc.). The rating for Risk Element B1 is Medium.

None of the above conditions apply. Go to Step 4

. Step 4 Given that the pest is capable of dispersing on its own or through a widely prevalent vector, the following conditions should apply to the pest you are assessing.  Suitable hosts are widely and regularly distributed throughout the entire endangered area.  Suitable hosts in the endangered area are available regardless of season.  No alternate hosts are needed to co mplete development or, if needed, are widely available.  All environmental requirements are usually met for the pest’s transferto a suitable host in the endangered area (e.g., wind, water, temperature). The rating for Risk Element B1 is High. Risk Element B1: Likelihood of coming into contact with host material in the endangered area Use the following guidance to determine the risk rating for Risk Element B1. Provide your rating, rate your uncertainty, and provide a narrative explanation for your decision.

IF THENConducting Pest Risk Assessment in PPQ Process 7: Assessing the likelihood of introduction

2-45 Guidelines for Plant Pest Risk Assessment ofImported Fruit & Vegetable Commodities 08/2012-1 Risk Element B2: Likelihood of ar riving in the endangered area. 

### In most cases, we have little information about comm odity movement in the PRA area. For this reason, in the absence of specific evidence, we assume that commodities move throughout the PRA area in proportion to consumer popul ation size, with more populous areas getting more of the commodity than less populous areas. This assumption implies that larger vol umes of the commodity will be moved to more populated areas, thus increasing the risk of pests entering those areas. We, however, are not taking into account the actual volumes of the commodities arriving in different areas as such information is not readily available and is prone to market fluctuations.
If specific information exists about where the commodity is most likely to move, its shipping frequency, or seasonal ity, this information can be used to determine more precisely the likelihood of the pest finding a suitable climate. For example, if we have evidence that a commodity would be imported only to an area where certain ethnic markets are located, and this region is outside the endangered area, or that the commodity is intended for spec ific seasons (e.g., holidays), such information can be used to lower the rating (see Step 2 ).
If the endangered area described in Process 5: Collecting information and defining the endangered areais defined in terms of temperature or plant hardiness zones, we may use Supplement 2: Plant Hardiness Zones Area and Population Analysis to easily find the percentage of the U.S. population that occurs within the zones corresponding to the endangered area. If the endangered area is defined in another way, we use the latest U.S. census to calculate the total population in the PRA area and in the endangered area. We calculate the proportion of the population in the endange red area relative to the population in the PRA area.

NOTE A rating of Negligible is not possible for Risk Element B2, because an endangered area has been identified within the PRA area, and we assume that any commercial trade volume is significant enough for there to be some risk.Conducting Pest Risk Assessment in PPQ Process 7: Assessing the likelihood of introduction

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-46

Risk Element B2: Likelihood of arriving in the endangered area Determine the base rating for this element using the criteria below.

IF THEN Step 1 Less than 10 percent of t he population lives within the endangered area. The rating for Risk Element B2 is Low. Go to Step 2

. Between 10 and 25 percent of the population lives within the endangered area. The rating for Risk El ement B2 is Medium. Go to Step 2

. Greater than 25% of the population lives within the endangered area. The rating for Risk Element B2 is High. Go to Step 2

. Based on the criteria in Step 2 , adjust the rating from Step 1 up or down as appropriate. Then go to Procedure 7-3: Determining the combined likelihood of establishment

. Step 2 You do not have specific information about the distribution of the commodity (including its destination, shipping season, frequency, etc.), or what is known about its distribution is unlikely to change the risk. Your analysis of Risk Element B can stop here. Continue to Procedure 7-3: Determining the combined likelihood of establishment

.
At least one of the following statements applies:  The commodity is likely to solely be distributed in specialty markets outside of the endangered
area.  The commodity has a very short shipping season (e.g. 1 month or less)  The commodity will only be imported infrequently (e.g., less than 5 times) in small quantities duringtimes of year that would prevent pest establishment (e.g., winter months). Decrease the risk rating for B2 by one level.
B2 becomes B2’
H M

M L

L Negl.*

*Requires a high degree of uncertainty (i.e., a rating of C or MC); otherwise, leave as Low.
Either of the following statements apply:  The commodity is likely to be distributed mainly to markets within the endangered area throughout the year, including seasons that are favorable for pest establishment.  Either high volumes or frequency of imports justify increasing the risk rating. Increase the risk rating for B2 by one level.
B2 becomes B2’
H H

M H

L MConducting Pest Risk Assessment in PPQ Process 7: Assessing the likelihood of introduction

2-47 Guidelines for Plant Pest Risk Assessment ofImported Fruit & Vegetable Commodities 08/2012-1 

## Procedure 7-3. Determining the combined lik elihood of establishment

Risk Element B: Combined likelihood of establishment 

### The matrix in this procedure is used to combine Risk Element B1: Likelihood of coming into contact with host material in the endangered area and Risk Element B2: Likelihood of arriving in the endangered areain order to determine the overall like lihood of the pest becoming established in the endangered area via the specific commodityimport pathway. If Risk Element B1 is Negligible, the over all likelihood of establishm ent (Risk Element B) is Negligible and no further analysis is need ed. This is shown as “no analysis” in the matrix below. The other values fo r the Likelihood of Establishment are found as the intersection in the matrix fo r the ratings of Risk Elements B1 and B2.

Risk Elements B1 and B2 wi ll be rated High when the pest is likely to come in contact with suitable hosts in the endangered area (during times favorable for pest establishment) and it coincides witha large consumer presence in the area. If either risk element is not ranked High, then Risk Element B1: Likelihood of coming into contact with host material in the endangered area is the “weighting” factor for th e likelihood of establishmen t (e.g., a combination of High and Medium ratings becomes High). Th e assumption is that pest’s ability to come in contact with hosts is an in trinsic factor for that pest-commodity association and remains stable regard less of the area of the commodity’s distribution. Distribution of the commodity is more li kely to be affected by changes in market demands or in demographics.Conducting Pest Risk Assessment in PPQ Process 7: Assessing the likelihood of introduction

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-48 

### Determining the overall likelihood of introduction 

### If the overall likelihood of introduc tion is High, this implies possible continuous entries of si zable pest populations ( Risk Element A: Likelihood of entry is High or Medium) and high like lihood of the commodity being moved to parts of the Endangere d Area with the High consum er population and of the pest’s High ability to transfer to a new host ( Risk Element B: Likelihood of establishment is High). If the likelihood of pest entry ( Risk Element A: Likelihood of entry ) is Low and the likelihood of establishment in the endangered area ( Risk Element B: Likelihood of establishment ) is High, the overall rating will be Me dium. Similarly, if the likelihood of introduction is Low, this implies possible irregular entries of smaller pest populations ( Risk Element A: Likelihood of entry is Low or Medium) and limited opportunity for the pest to be moved to areas with high consumer populati ons and/or limited ability of the pest to come into contact with host material ( Risk Element B: Likelihood of establishment is Low). Risk Element B: Combined likelihood of establishment Combine Risk Elements B1 and B2 using the matrix in this pr ocedure to determine the rating for Risk Element B. In the risk assessment, state the rating, rate your uncertainty, and provide a narrative explanation for your decision.

Risk Element B1: Likelihood of coming into contact with host material in the endangered area Negligible Low Medium HighRisk Element B2:Likelihood of arriving inthe endangered area Highno analysis M M H

Medium L M H

Low L M MConducting Pest Risk Assessment in PPQ Process 7: Assessing the likelihood of introduction

2-49 Guidelines for Plant Pest Risk Assessment ofImported Fruit & Vegetable Commodities 08/2012-1 

## Procedure 7-4. Determining the overall lik elihood of introduction

The rating for overall Likelihood of Intr oduction is weighted towards pest establishment because this element is more important. If the pest cannot establish then the likelihood of entry becomes irrelevant. Once a pest has entered, we are most concerned wi th its establishment potential.

Risk Element B: Combined likelihood of establishment Combine the ratings for the likelihoods of entry (Risk Element A) and establishmen t (Risk Element B) into a rating for the overall likelihood of introduction according to the matrix belo w. If either entry (Risk Element A) or establishment (Risk Element B) is rated Negligible, the overall likelihood of in troduction is Negligible and no further analysis is needed.

Risk Element B: Likelihood of Establishment Low Medium HighRisk Element A:Likelihood of Entry High M M H

Medium L M H

Low L M MConducting Pest Risk Assessment in PPQ Process 8: Assessing potential consequences of introduction

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-50 

## Process 8: Assessing potential consequences of introduction The purpose of this process is to determine whether the introduction of the pest would result in unacceptable economic c onsequences in terms of the potential agricultural, environmental, and social im pacts that could result from the pest establishing in the endangered area. We evaluate the consequences of introduction without resp ect to the pathway of introduction by assuming a hypothetical situation where the pest is introduced and fully expressing its potential economic consequen ces in the endangered area.
We evaluate both direct impacts (i.e., impacts resulting from pest damage to host plants) and trade impacts. In gene ral, we do not identify or evaluate indirect impacts beyond potential trade impacts, even though we acknowledge that such impacts are often unacceptable. However, it is not the purpose of this analysis to estimate the magnitude of the total impacts, but instead only to determine whether a given pest is li kely to cause unacceptable economic consequences. Therefore, it is sufficie nt to limit our eval uation of potential consequences to the direct pest effects and the potenti al impacts to trade. Any other unacceptable imp acts would likely occur as a re sult of one or more direct or trade impacts.
Similarly, although in practice the total c onsequences of intr oduction of a pest would be dependent on the rate and manner of spread in the PRA area, because, again, we are not estimating th e magnitude of the total consequences, it is sufficient for the purposes of this analysis to simply determine if the spread potential of the pest is signif icant enough that it would be likely to spread throughout the endangered area within a reasonabl e period of time. Pests that have a Low or Negligible spread potential are not likely to cause unacceptable impacts unless the damagepotential of the pest is High.
Pests that are likely to cause unaccepta ble consequences are termed “threshold pests”; those that are not likely to cau se unacceptable consequences are termed “non-threshold pests.” By us ing this approach we e xplicitly acknowledge that non-threshold pests may cause some damage in the PRA area; however, that level of damage is expected to below enough that routine port-of-entry inspection will be sufficient to mitigatethe risk associated with their possible entry. Threshold pests, on the other hand, are expected to cause a level of damage that may warrant additional phytosanitary measures beyond routine port-of-entry inspection (to reduce their likelihood of entry) in order to meet the acceptable level of risk.
A pest is not likely to cause unacceptabl e direct impacts in the endangered area if any of the following criteria applies:
 The pest is not likely to cause sign ificant losses to commercial or noncommercial plants as a result of mi tigating conditions in endangered area.Conducting Pest Risk Assessment in PPQ Process 8: Assessing potential consequences of introduction

2-51 Guidelines for Plant Pest Risk Assessment ofImported Fruit & Vegetable Commodities 08/2012-1 

###  Should the pest become established inany portion of the endangered area, its ability to move beyond its initial point of introduction is very limited, so that spread in the endangered area is likely to be very slow or negligible, limiting any potential damage to a localized area. A pest is not likely to cause unacceptable trade impacts if hosts of the pest are not exported, if the pest already occurs in countries importing commodities from the endangered area that are likely to be pathways for moving the pest, or if the countries alrea dy require phytosanitary m easures for the exported commodity that will be ef fective against the pest.
In determining whether a pest will cause unacceptable damages to the PRA area, we evaluate how the pest is behaving in its cu rrent area of distribution. When the evidence suggests that a gi ven pest is behaving differently in different parts of its dist ribution, we place emphasis on how the pest behaves in the parts of the distribution most similar to the endangered area. In many cases, there is little evidence to predict how a pe st will behave in the endangered area. In these circumstances, our uncertainty rating may be high, and such pests should be explicitly identified inthe notes to the risk managers.
Once it can be shown that the consequenc es of the pest’s establishment in the PRA area will likely exceed a certainthreshold of damage, the pest is determined to be a threshold pest. It is beyond the scope of this analysis to attempt to quantify, estimate, or predict th e magnitude of potential pest effects. It is important to understand, therefore, th at the analysis of a particular pest will not necessarily identify all of the potential impacts that would likely result from its introduction. This approach is consistent with ISPM No. 11 (2004b), which acknowledges that detailed analysis of the cons equences of introduction is not necessary when it is widely ag reed that pest introduction will have unacceptable consequences. Th e approach is sufficient for most pests analyzed in commodity import assessments., but a mo re detailed economic analysis of potential consequences can be conducted separately, if needed.Conducting Pest Risk Assessment in PPQ Process 8: Assessing potential consequences of introduction

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-52 

## Procedure 8-1. Determining the potential di rect impacts (Risk Element C)

Risk Element C: Determining the potential direct impacts Risk Element C1: Damage potential in the endangered area. 

### Consider the climate and cultural conditions that ex ist in the endangered area and decide whether the introduction of the pest inthe endangered area will result in unacceptable economic (incl uding environmental and soci al) damage or loss to plants in the endangered area. Assume a hypothetical situation where the pest is introduced throughout the endangered ar ea and fully expressing its potential economic consequences. In general, you should consider only evidence related to plants identified in Step 3 of Procedure 5-2: Defining the endangered area

. Do not consider symptoms/damage on unrelated plants, unless they are very similar.Conducting Pest Risk Assessment in PPQ Process 8: Assessing potential consequences of introduction

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Risk Element C1: Damage potential in the endangered area Step 1 Identify the climatic and cultural conditions in t he endangered area that are lik ely to impact the damage potential of the pest.
Consider:  climatic conditions that would affect pest population and/or virulence.  host distribution (including amount of production ofcultivated hosts and abundance of environmental hosts) in the endangered area.  conditions that would affect the status of conditional hosts.  current standard production practices of the cultivat ed hosts at risk (including any organic production). Note any practices that would likely mitigate the cons equences of establishment ofthe pest. Examples of such practices include:  pesticides routinely applied for other pests thatwould also control th e pest being assessed.  cultural control practices such as field sanitation, crop rotation, etc.  planting of host-resistant varieties and/or clean stock.  the presence and distribution of similar pests in the endangered area, including natural areas. Note the impact these pests currently cause in the endangered area. Consider questions such as  how would the damage caused by this pest compare?  how are similar pests in the endangered area being co ntrolled (including natural controls), if at all?  if control practices are in place, would they also mitigate this pest?
Continue to Step 2

. Step 2 With respect to the conditions in Step 1 , estimate the damage potential of the pest in the endangered area in terms of percent losses. Then go to Step 3

. Factors to consider:  how widespread each condition is in the endangered area (for example, consider standard production practices of commercial hosts vs. organic production, presence and density of environmental/wild hosts, etc.).  host preference and status.  type of damage caused by the pest on hos ts present in the endangered area (see Step 4 of Procedure 5-2: Defining the endangered area ).  ease of control. Are pest icides/treatments for the pest readily available?  ease of detection (affects surveillance and monitoring costs).  is pest likely to be mitigated/controlled by any of the conditions in the endangered area?Conducting Pest Risk Assessment in PPQ Process 8: Assessing potential consequences of introduction

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-54

Risk Element C1(a): Damage potential to commercial hosts

IF THEN Step 3 Either of the following statements apply.  The introduction of the pest in the endangered area would likely resultin 10 percent or greater yield losses in at least one commercially cultivated host.  The introduction of the pest would likely result in a significant increases in costs of production beyond normal annual fluctuations. For example, consider increased costs to producers due to the implementation of additional control practices (or regimes) in the endangered area (beyond those already in place for the control of similar pests) and/or costs associated with surveillance and monitoring. Potential damage in theendangered area is significant. In the risk assessment, indicate that the pest m eets the criteria for having the potential to cause unacceptable damage in the endangered area. Rate your uncertainty, summarize the evidence, and then proceed to Step 5

. Neither of the above statements apply. Go to Step 4

.

Risk Element C1(b): Damage pote ntial to non-commercial hosts

IF THEN Step 4 Either of the following statements apply.  The type of damage or symptoms ca used by the pest in the endangered area would likely result in population reduction (beyond normal fluctuations ) of threatened and endange red, or socially and other environmentally important plants. Do not consider “quality” losses. Do not consider host congeners unless you have evidence the pest damages multiple congeners.  The introduction of the pest in the endangered area would likely result in significant reductions of amenity va lues (due to obviously and visibly damaged plants) beyond normal annual fluctuations. Potential damage in theendangered area is significant. In the risk assessment, indicate that the pest m eets the criteria for having the potential to cause unacceptable damage in the endangered area. Rate your uncertainty, summarize the evidence, and then proceed to Step 5

. Neither of the above statements apply. Potential damage in theendangered area is not significant. In the risk assessment, indicate that the pest does not meet the criteria for having the potentialto cause unacceptable damage in the endangered area,rate your uncertainty, and summarize the evidence. Continue to Procedure 8-4: Determining potential trade impacts

.Conducting Pest Risk Assessment in PPQ Process 8: Assessing potential consequences of introduction

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### Risk Element C2: Spread potential 

### In this risk element, you will determine the likelihood that the pest will spread beyond its initial point of introduction within a reasonable amount of time. Pests that have a Low or Negligible spread potential are not likely to cause unacceptable impacts unless th e damage potential is High.

Risk Element C2: Spread potential Step 5 Consider the following factors:  current distribution and spread patterns of the pest. Fo r example, is the pest spreading rapidly around the world? How quickly is the distribution of the pest exp anding, particularly in areas it has been introduced that are climatically similar to the endangered area?  abundance and continuity of natural hosts in the areas in endangered ar ea. If applicable, consider if the pest requires altern ate hosts to complete its life cycle.  dispersal potential

 natural dispersal mechanisms (flight, vectors, rain/win d, etc.) and availability of such mechanisms in the endangered area.  intentional or unintentional movement of infected orinfested plants or plant products (for example, a pathogen infecting only leaves may not likely be move d by humans if the leaves are not part of the commodity).  intentional movement of the organism.  ability of the organism to hitchhike on conveyances.  relevant life history of the pest.

 life stages (including duration).  reproductive strategies (fecundity, part henogenesis, alternating generations, etc.).  adaptive characteristics (dormancy, expansion of a hos t range, climatic toler ance, i.e., supercooling, etc.).  ease of detection.  control or mitigation practices in the endangered area that would limit spread.
Continue to Step 6

.Conducting Pest Risk Assessment in PPQ Process 8: Assessing potential consequences of introduction

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-56 IF THEN Step 6 The pest is already present in some portion of the endangered area. Go to Step 7

. The pest is not already present in the endangered area. Go to Step 8

. Step 7 The pest has been present in the endangered area for more than 10 years and is not part of an official progr am for eradication, containment, or area-wide control. Spread potential is not significant. In the risk assessment, indicate that the pest does not have a significant spread potential,rate your uncertainty, and summarize the evidence. Continue to Procedure 8-3: Additionalanalysis for pests with undetermined trade impact

. The pest has been present in the endangered area for fewer than 10 years

. Go to Step 8

.
Step 8 Evidence indicates that the pest is spreading or has spread in other parts of the world



### —that is, the distribution of th e pest is expanding, particularly in areas where it has been intro duced that are climatically similar to the endangered area. Spread potential is significant. In the risk assessment, indicate that the pest has a significant spread potential, rate your uncertainty, and summarize the evidence. Continue to Procedure 8-2: Determining ifthe pest is likely to cause unacceptable direct economic impacts

. There is no evidence that the pest is spreading or has spread in other parts of the world. Go to Step 9

.Conducting Pest Risk Assessment in PPQ Process 8: Assessing potential consequences of introduction

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Step 9 Any of the following statements apply.  The pest requires specific vectors fo r dispersal that are not present in the endangered area.  The pest has limited natural dispersal potential and is unlikely to be moved by humans. Consider the likel ihood of humans moving the pestfrom an area of establishment in the endangered area to another portion of the endangered area (e.g., purposeful movement, accidental movement on plant parts in domestic trade, movement on fomites, etc.). Do not consider interception records.  The dispersal abilities of the pest would not allow it to access the available hosts (e.g., hosts are patchy/non-continuously distributed, separated by geographic barriers, non-persistent vectors).  The dispersal stage requires a s pecific combination of conditions which rarely occur together (e.g., wind-rain event at a particular life stage). Spread potential is not significant. In the risk assessment, indicate that the pest does not have a significant spread potential,rate your uncertainty, and summarize the evidence.Procedure 8-3: Additional analysis for pests with undetermined trade impact

.

None of the above statements apply. Spread potential is significant. In the risk assessment, indicate that the pest has a significant spread potential, rate your uncertainty, and summarize the evidence. Go to Procedure 8-2: Determining if the pest is likely to cause unacceptable direct economic impacts

. IF THENConducting Pest Risk Assessment in PPQ Process 8: Assessing potential consequences of introduction

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-58 

## Procedure 8-2. Determining if the pest is likely to cause unacceptable direct economic impacts

Determine the likelihood of the pest to cause unacceptab le direct economic impacts by combining the ratings for the damage potential (Ris k Element C1) and spread potential (Risk Element C2) according to this procedure.

IF AND THEN The damage potential (C1) was not significant. The pest is not likely to cause unacceptable direct impacts in the endangered area.
Go to Procedure 8-4: Determining potential trade impacts

. The damage potential (C1) was significant. The spread potential (C2) was significant. The pest is likely to cause unacceptable direct economic impacts in the endangered area. To analyze trade impacts (only necessary upon special request), go to Procedure 8-4: Determining potential trade impacts

. Otherwise, continue to Process 9: Summarizing the final risk ratings and uncertaintyon page 2-63 if the likelihood of introduction has already been completed for this pest, or to Process 7: Assessing the likelihood of introduction on page 2-35 if the likelihood of introduction has not been completed. The damage potential (C1) was significant. The spread potential (C2) was not significant. The likelihood of the pest causing unacceptable direct economic impacts cannot be determined at this point. Continue to Procedure 8-3: Additional analysis for pests with undetermined trade impact

.Conducting Pest Risk Assessment in PPQ Process 8: Assessing potential consequences of introduction

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## Procedure 8-3. Additional analysis for pests with undetermined trade impact

Pests that have a significant damage potential but do not have a significant spread potential may or may not meet the criteria for causing unacceptable direct impacts. Follow this procedure to determine the likelihood of causing unacceptable direct economic impacts for a pest whose likelihood of causing unacceptable direct economic impacts could not be determined using Procedure 8-2: Dete rmining if the pest is likely to cause unacceptable direct economic impacts

. IF THEN Evidence suggests that the pest is capable of causing major damage (i.e., 50 percent field losses) and it meets one of the following criteria:  Most of the commercial production of one or more of the pest’s hosts occurs within a small area, such as a single hardiness zone, county, or other defined region.  The pest is associated with a threatened or endangered species found in the endangered area. Consider the pest to meet the threshold of causingunacceptable direct economic impacts in the endangered area.

The above does not apply. Consider the pest to not be likely to cause unacceptable direct economic impacts in the endangered area and analyze the trade impacts using Procedure 8-4: Determining potential trade impacts

. If potential trade impacts have already been analyzed and they are not likely to signifi cant, conclude that the pest does not meet the threshold for causing unacceptable economic impacts.Conducting Pest Risk Assessment in PPQ Process 8: Assessing potential consequences of introduction

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-60 

## Procedure 8-4. Determining potential trade impacts

Risk Element D: Determining potential trade impacts 

### Based on the total market for the host commodities at risk (identified in Step 3 of Procedure 5-2: Defining the endangered area ), determine if introduction of the pest in the endangered area woul d likely result in unacceptable trade impacts to the PRA area, in terms of losses of existing export markets.

Risk Element D1: Determining export markets at risk. 

### NOTE Trade impacts are analyzed for the entire PRA area, not just the endangered area, because the entire PRA area may be impacted if the pest is able to establish in any portion of it. For example, trading partners may impose provisional measures until it can be demonstrated that the pest will no t establish outside of the defined endangered area. Should the pest become established in the PRA area, there may be costs associated with demonstrating and maintaining pest-free areas (e.g., costs associated with surveys).

Risk Element D1: Export markets at risk

IF THEN Step 1 Determine whether plant products potentially affected by the pest have been exported from the PRA area in the past five years. Consider t he specific plant part(s) being exported, and the pest association with these parts. No host commodities are currently being exported. The pest is not a threshold pest. The analysis of potential trade impacts can stop here. Continue to Process 9: Summarizing the final risk ratings and uncertainty on page 2-63

. Host commodities are currently being exported. Go to Step 2

.
Step 2 Identify the export markets of the host commodities identified in step 1 from the PRA area anddetermine which of these markets are currently free from the pest or consider the pest to be of quarantine significance. No export market is currently free from the pest (i.e., the pest is currently distributed everywherethat host commodities are currently being exported from the PRA area). The pest is not a threshold pest. The analysis of potential trade impacts can stop here. Continue to Process 9: Summarizing the final risk ratings and uncertainty on page 2-63

. At least one export market for atleast one host commodity is currently free from the pest. Go to Step 3

.Conducting Pest Risk Assessment in PPQ Process 8: Assessing potential consequences of introduction

2-61 Guidelines for Plant Pest Risk Assessment ofImported Fruit & Vegetable Commodities 08/2012-1 Risk Element D2: Likelihood of trad ing partners imposing additional phytosantiary requirements. 

### In completing Step 4 , consider factors such as:
 degree to which the exported commodity is processed. For example, is the exported commodity processed in such a way that the pest has a negligible likelihood of being moved with the commodity?  current phytosanitary requirements already in place for the commodity. For example, do trading partners al ready require phytosanitary measures (for other pests) that would also mitigate th is pest? (PCIT/EXCERPT)  likelihood of taking action against the pest. For example, do trading partners currently maintain regulati ons for the pest? Do they currently take action on similar pests? Are theyunlikely to take action against the pest because it is unlikely to establish in the country ? (PCIT/EXCERPT; Trade director)  importance of domestic production in th e trading countries. For example, do trading partners have significan t domestic production of any hosts associated with the pest? (FAO Stat s). Do they export significant amounts of host commodities to countries that are free of the pest? (GTIS for trade; CABI, etc. for pest freedom)  trade with other countries where the pest is currently distributed. For example, are trading partners currently importing host commodities from other countries where the pest is distributed? Under what conditions? What kinds of phytosanitary measures are required? Step 3 Determine the export value ofhost commodities that are typically exported to countries free from the pest or to countries where the pest is considered to be of quarantine significance. In general, you should start with major export commodities The value of any commodity exported to countries free fromthe pest is greater than 10 percent of the total export value of that commodity. Go to Step 4

.

The export value of every commodity exported to countries freefrom the pest is less than 10 percent of the total export value of that commodity. The pest is not a threshold pest. The analysis of potential trade impacts can stop here. Continue to Process 9: Summarizing the final risk ratings and uncertainty on page 2-63

. Risk Element D1: Export markets at risk

IF THENConducting Pest Risk Assessment in PPQ Process 8: Assessing potential consequences of introduction

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-62

Risk Element D2: Likelihood of trading partners imposing additional phytosanitary requirements

IF THEN Step 4 Trading partners that are currently free from the pest would be likely to impose an export ban on host co mmodities, or require the implementation of additional phytosanitarymeasures on them as a condition of export. The pest is a threshold pest. If you’ve already completed the likelihood of introduction for this pest, continue to Process 9: Summarizing the final risk ratings and uncertaintyon page 2-63

. Otherwise, go to Process 7:Assessing the likelihood of introduction on page 2-35

. The above does not apply. The pest is not a threshold pest. The analysis of potential trade impacts can stop here. Continue to Process 9: Summarizing the final risk ratings and uncertainty on page 2-63

.Conducting Pest Risk Assessment in PPQ Process 9: Summarizing the final risk ratings and uncertainty

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## Process 9: Summarizing the fina l risk ratings and uncertainty For this process, we brie fly summarize the results for the pests analyzed in Process 7: Assessing the likelihood of introductionand Process 8: Assessing potential consequences of introduction . For each pest, we separately present the overall result or rating for the li kelihood of introducti on assessment and the overall result for the consequences assessment.

The final result of the qualitative uncertainty assessment should be the identification of most relevant sources of uncertainty and technical means for reducing them, as well as the evaluation of the overall effect of uncertainty sources on the risk estimate. NOTE The results for likelihood and consequences of introduction are not combined to give one overall risk rating. We use these over all results to determine which of the analyzed pests are candidates for risk management and which are not. If warranted, we also provide a summary of the uncertaintyassociated with each pest analysis.



## Procedure 9-1. Summarizing the final risk ratings and uncertainty

Follow the steps of this procedure to summa rize the final risk ratings and uncertainty.

IF THEN The pest meets at least one of the following criteria:  no portion of the PRA area is likely to be endangered by the pest (i.e., the area endangered by the pest is Negligible).  does not meet the threshold to likely cause unacceptable consequences of introduction.  received a Negligible overall risk rating for likelihood of introduction. The pest is not a candidate for risk management.In the “Summary and Conclusions” section of the risk assessment, summarize this list of pests in a table that contains, foreach pest, the reason the pest is not a candidate for risk management. For each pest, if warranted, provide an uncertaintystatement in the table; this statement should focus on identification of the most relevant sources of uncertainty and technical means for reducing them, as well as the evaluation of the overall effect of uncertainty sour ces on the risk estimate. The pest meets the following criteria:  meets the threshold to likely cause unacceptable consequences of introduction.  received an overall risk rating for likelihood of introduction above Negligible. The pest is a candidate for risk management.In the “Summary and Conclusions” section of the risk assessment, summarize this list of pests in a table that contains, for each pest, the likelihood of introduction overall rating (i.e., High, Medium, or Low). Note that the results of the consequences of introduction assessment do not need to be included in this table,as all these pests meet the threshold for unacceptable consequences. For each pest, if warranted, provide an uncertaintystatement in the table; this statement should focus on identification of the most relevant sources of uncertainty and technical means for reducing them, as well as the evaluation of the overall effect of uncertainty sour ces on the risk estimate.
Continue to Process 10: Risk mitigation notes on page 2-67

.Conducting Pest Risk Assessment in PPQ Risk Management in pest risk analysis

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-64 

# Stage 3: Risk Management Risk Management in pest risk analysis The core elements of pest risk anal ysis are risk assessment and risk management. Pest risk management is de fined by the IPPC as the “evaluation and selection of options to reduce the ri sk of introduction and spread of a pest” (ISPM No. 5: IPPC, 2012). This means that mitigations may be applied at any point in the production chain to reduce likelihood of entry (e .g., pre-border); or to reduce likelihood of establishment or spread (e.g., post-border).
There are three general asp ects to risk management th at should be considered: policy, analytical and operational. The policy aspect is that part of risk management where overall policy is co nsidered, including the appropriate level of protection/acceptable level of ri sk. Several key principles of the SPS and IPPC apply to the policy aspects of risk management, including in particular the
 application of the appropriatelevel of protection (ALOP),  principle of least trade restric tive measures (minimal impact),  principle of non-disc rimination (including national treatment),  principle of managed risk, and  principle of equivalence.

Non-technical factors (e.g., social and political concerns) may be considered under the policy component of risk manage ment, or for instance, priorities for risk management may be decided by broa der policy issues. Since zero-risk is not a reasonable option, risk manageme nt should focus on reduction of risk that can be justified and is feasible wi thin the limits of available options and resources. In any case, the overarching pol icy of the NPPO, together with any country/commodity-specific pol icies, is usually the main driver in the ultimate decision-making stages for ri sk management. Usually th e policy aspects of risk management are beyond the purview of the individual risk analyst—these decisions are carried out by decision-makers that are not involved in the risk assessment stage of PRA.
The analytical aspect of risk manageme nt is the component that considers and weighs various options for mitigating ri sk. Options are usually analyzed for efficacy and feasibility, and to some extent costs associated with various options. The analysis of options in pest risk management necessitates a close linkage with the pest risk assessment part of PRA. The risk assessment shouldConducting Pest Risk Assessment in PPQ Risk Management in pest risk analysis

2-65 Guidelines for Plant Pest Risk Assessment ofImported Fruit & Vegetable Commodities 08/2012-1 

### provide relevant information and analys is regarding a particular pathway(s), control points, uncertainties identified in the assessment, pests likely to be in a pathway, and important information about the biology of the pest that may factor into the selection of risk mana gement options (e.g., feeding strategies, host status, etc.). Risk management is therefore dependent on the risk assessment to provide in formation about what mitigation options may be useful, and how various mitigation options will affect overall risk.
The operational aspect of risk management is the selection and application of mitigation options that are decided upon based on the policy and analytical components of pest risk management. For imported commodities, this may be the designation of a specific work pl an between trading partners, or the implementation of a preclearance progr am. Work plans will outline the activities that must be undertaken fo r the commodity to be imported (e.g., specified areas for export, packing condi tions, treatments, etc.). Depending on the commodity, the pests and the level of risk involved, the operational component may be fairly simple (a single phytosanitary treatment like fumigation) to highly complex (a larg e-scale systems approach for managing several pests). The IPPC has produced several standard s that provide general guidance on pest risk management, as we ll as some standards thatprovide specific guidance on particular aspects of pe st risk management—for instance, standards that address pest-free areas, sp ecific pests like fruit fl ies or specific types of phytosanitary treatments. The ISPMs particularly relevant to pest risk management, and which may be consulted in identify ing options, are shown in Table 2-2

.Conducting Pest Risk Assessment in PPQ Uncertainty in risk management

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-66 

## Uncertainty in risk management The primary purpose for identifying and communicating un certainty is to provide the decision maker with as completeand objective a view of the risk as possible. Carefully noting and considering uncertainty in PRA also helps governments to identify priority rese arch needs and highlights for trading partners the points where the provision of more or better information may improve a decision. The uncertainty noted in the assessments of economic consequences and likelihood of introduc tion should also be considered and included in the analysis of risk management options.
Where there is significant uncertainty, a conservative approa ch may be adopted as a temporary measure. However, the me asures selected must nevertheless be based on a risk assessment that takes into account the available scientific information. In these circumstances the measures should be accepted as provisional and reviewed as soon as a dditional information becomes available.
The overall approach to dealing with uncertainty is addressed as a policy question, but it is the responsibility of th e risk analyst to highlight uncertainty in the analysis and the potential ef fects of uncertainty during the risk management stage. Table 2-2. ISPMs with special relevance for pest risk management.

ISPM No. Title
1 Phytosanitary principles for the protection of plants and the application of phytosanitary measures in international trade
4 Requirements for the establishment of pest free areas
10 Requirements for the establishment of pest free places of production and pest free production sites
14 The use of integrated measures in a systems approach for pest risk management 18 Guidelines for the use of irradiation as a phytosanitary measure
22 Requirements for the establishment of areas of low pest prevalence
23 Guidelines for inspection
24 Guidelines for the determination and recognition of equivalence of phytosanitary measures
26 Establishment of pest free area s for fruit flies (Tephritidae)
28 Phytosanitary treatments for regulated pests
29 Recognition of pest free areas and areas of low pest prevalence
30 Establishment of areas of low pest prev alence for fruit flies (Tephritidae)
32 Categorization of commodities according to their pest riskConducting Pest Risk Assessment in PPQ Process 10: Risk mitigation notes

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## Process 10: Risk mitigation notes In APHIS-PPQ, the processes of risk assessment and risk management for commodity imports are conducted sepa rately and by two different groups within PPQ. Although individual risk anal ysts are not ultimately involved in developing the risk management for document for commodity imports, the analyst(s) that conducts the assessment is in the best position to provide analytical information that will informthe decisions being made about risk management. This information is placed in an internal document called “risk mitigation notes” to be shared with the ri sk managers to ensure that important information that would be of potential use in risk management is not lost. Preparing the risk mitigation notes is an informal process that will vary from analysis to analysis, but general guidance is on preparing this document is provided here.
Guidance for preparing risk mitigation notes
Step 1: Identify possible options General options. 

### Traditionally, measures appl ied to imported commodities have relied on high-efficacy (e.g., probit-9 mortality) phytosanitary treatments aimed at reducing the presence of a partic ular pest (e.g., a species of fruit fly) on a given commodity. For example, phytosanitary treatme nts may include fumigations, cold treatments, heat treatme nts, or irradiation. However, a wide array of measures may be applied to mitigate risk (either singly or in combination), in addition to traditional phytosanitary treatme nts. The measures listed below are examples of those that are most commonly applied to traded commodities. The available me asures can be classifiedinto broad categories. These include measures (ISPM No. 11: IPPC, 2004a):
 applied to the commodity post-ha rvest (e.g., brushing, washing, waxing, treatments),  applied to prevent or reduce originalinfestation of the commodity by a pest(s) (e.g., integrated pest management (IPM) programs, bagging, safeguarding, sanitation, etc.),  applied to ensure the area or place of production of the consignment is free from the hazard (e.g. pest free areas or areas of low pest prevalence), and  concerning the prohibition of commodi ties (in the absence of any other feasible options).Conducting Pest Risk Assessment in PPQ Process 10: Risk mitigation notes

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-68 Specific options. 

### In Table 2-3 , we summarize many of the risk management options commonly applied pre- and post -harvest to commodities to reduce, prevent or eliminate quarantine pests (IPPC, 2002). Insome cases, a single measure may be sufficient to manage risk (e.g., a high mortality treatment); however, in many cases, additional measures are needed to reduce risk to an acceptable level.

Table 2-3. Measures that can be applied to ma nage pest risk^ (IPPC, 2002; Jang and Moffit, 1994).
Pre-harvest Pest-free areas or areas of low pest prevalence
Resistant cultivars Healthy planting material Pest mating or development disruption
Sanitation and cultural controls
Certification schemes Testing
Protected conditions* Harvest Harvesting at specific times or specific stages of ripeness Culling infested products
Field sanitation Harvest technique
In-field chemical treatments
Field surveillance Tarping*
Sanitation* Post-harvest handling Post-harvest treatments (che mical, heat, waxing, washing brushing, etc.) Testing Culling Packinghouse inspection Processing (degree and type) Method of packing* Screening*
Sanitation* Shipping Treatment in transit (e.g., cold treatment) Speed and type of transport Pre-shipment inspection Testing
Sanitation* Type of packaging*Conducting Pest Risk Assessment in PPQ Process 10: Risk mitigation notes

2-69 Guidelines for Plant Pest Risk Assessment ofImported Fruit & Vegetable Commodities 08/2012-1 Systems approaches and control points. 

### “Systems approach” is defined as “the integration of different ri sk management measures, at least two of which act independently, and which cumulativelyachieve the appropriate level of protection against regulated pests” (I PPC, 2012). Systems approaches may be applied in cases where a si ngle measure, such as a phytosanitary treatment, is either not available or is not likelyto achieve the appropriate level of phytosanitary protection or in cases where the only other alternative is prohibition. The cumulative effect of combining independent measures can provide the necessary level of phyt osanitary protection where no other alternatives are available.
Systems approaches include inde pendent measures, redundancy, and safeguarding. Combining meas ures that act independently of each other has the advantage that if any one measure fail s, the overall system maintains a high level of efficacy. Similarly, includi ng redundant (or overlapping) measures means that if one measure applied at a particular point in the production chain fails, another measure direct ed at that same point will assure that mitigation of risk still occurs. Lastly, measures that do not necessarily reduce pest prevalence, but that are aimed at preventing any new risk from being introduced into the system are calle d “safeguards” (IPPC, 1999; Follett and Neven, 2006).
The types of measures that are app lied in a systems approach can occur anywhere in a production chain, from pre-planting and pre-harvest through distribution and final end- use of the commodity ( Table 2-3 ). Thus, the main advantage of systems approaches is th at the risk is managed beginning at origin, thereby reducing the level of risk for the importing country. Systems approaches can also be usedto mitigate the risk of pests that are not normally

Distribution Restrictions on ports of entry Restrictions on time of year Post-entry quarantine Post-entry Inspection Post-entry treatment Packaging* End use Restrictions on end-use Post entry processing Packaging* *Indicates a safeguarding measure (see section on Systems Approaches). ^This table is not inclusive of all potential meas ures; it lists the most common measures used on imported commodities. Table 2-3. Measures that can be applied to manage pest risk^ (IPPC, 2002; Jang and Moffit, 1994).Conducting Pest Risk Assessment in PPQ Process 10: Risk mitigation notes

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-70 

### associated with the commodity (hitchhikers or contaminating pests), or pests that are not accounted for in the PR A process (unknown pests) (MAF, 2008).
In general, the use of a systems appr oach requires a relatively good knowledge of the production practi ces, the biology of the pest(s), and its relationship to the host(s) and post-harvest practices. In many cases, a systems approach can be highly flexible in the number and type of measures applied (as long as at least two measures act independently), even if specific data on efficacy is lacking. The number and types of measures combined in a systems approaches can range from very simple co mbinations (e.g., two indepe ndent measures such as low pest prevalence combined with fumigation) to highly complex, “control point” systems (IPPC, 1999; IPPC, 2002). This is dependent on the  level of risk involved;  cost, feasibility, and effi cacy of possible measures;  suitability of any given manageme nt option for managing that risk;  availability of information for th e pest(s) and associated commodity;  the level of uncertainty; and  the appropriate level of protecti on (or acceptable level of risk).

The role of control points in risk management and systems approaches. 

### For the purposes of this discussion, it is useful to make a distinction between “control points” and “critical control points.” Control points are points where controls can be applied in the productio n chain, and the controls are expected to have some effect on the system (i.e., a reduction in risk). We may or may not be able to measure the exact effect of th e control, but we would expect that the control would have some (p erhaps undefined) level of efficacy. An example of a control point that may be difficult tomeasure would be field sanitation and the removal of fallen fruit from orchards to manage risks a ssociated with fruit flies. We know that sanitation would reduce risk, but th e exact level of efficacy would be difficult to measure. In addi tion, certain measures or conditions exist or are included to compensate for uncertainty. These may not be monitored as independent procedures (e .g., packinghouse sorting), or may be monitored but not controlled (e.g., host pr eference/susc eptibility).

In other cases, the control points may be well defined, and the level of efficacy of that control can be measured, qu antified, monitored, and verified. In addition, such points in the system may be points where controls must be applied in order to reduce risk sufficiently. These would be re garded as critical control points. For some co mmodities, most or all of the specific points in the production chain can be well defined, the hazards and mitigations can be measured, each point can be controll ed, and the efficacy of each mitigationConducting Pest Risk Assessment in PPQ Process 10: Risk mitigation notes

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### step can be verified and documented. In these cases, a “critical control point” system can be applied—this being the mo st rigid type of systems approach used for phytosanitary risk management (IPPC, 1999).
The use of a control point system for phytosanitary purposes does not imply or prescribe that application of controls is necessary to all control points. These are addressed by risk management pr ocedures whose contribution to the efficacy of the system can be measured and controlled.
Even if a critical control point system is not used in risk management, the analysis of control points and critical c ontrol points may be useful to identify and analyze hazards as well as the poi nts in a pathway where risks can be reduced and monitored and adjustments made where necessary.
Step 2: Identify information and option for risk management 

### The risk analyst is uniquely positioned to provide relevant information for the formulation of risk management optio ns and plans. Throughout the analysis, the risk analyst should have documen ted information relevant to risk management for
 quarantine pests likely to follow the pathway,  the pathway itself (see Process 3: Defining the pathway on page 2-6 ) and potential control points (and critical control points),  potential effects of mitigations, and  any uncertainty associated with the pest(s) and the pathway.

Table 2-4 and Table 2-5 provide examples of how and what type of information can be presented on both th e pathway and the pests. It includes information on the pathway (described inthe risk assessment) and information on pests gathered during the analysis that is particularly relevant to risk management. Figure 2-6 and Figure 2-7 are examples of a completed template using the fruit fly Dacus ciliates (pest) on Jordan beans (pathway).
Information presented to the risk manager should highlight potential mitigations for the pest(s) and the pathway, the anticipated effects of mitigations, and the level and source of uncertainty (if applicable). Note that analyzing the pathway for specific control points, as highlighted in the previous section may assist the analys t in determining whether mitigations applied at control points will have a si gnificant effect on the overall risk (e.g., critical control points). The informati on provided to the risk manager should include particularly critical details fr om the analysis (including relevantConducting Pest Risk Assessment in PPQ Process 10: Risk mitigation notes

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-72 

### uncertainty) that will aid in decision-making and in th e determination of which measures will be most effective, feasible and justified.

Table 2-4. Examples of the type of pathway in formation useful for risk managers.

Information relevant to risk mitigation Potential mitigations Anticipated effect or impact Uncertainty (level and source)
Pathway/commodity: include information on pathwa y/commodity/processing relevant to risk management. Information may come from exporting country or from technical sources. Production areas Protected cultivation, pest-free areas, or areas of low pest prevalence Prevention of infestation Lack of specific data Conflicting data
Variable dataVariability of commodityAvailability of technologySuitability of technologyEffects on or of commodity Need for monitoringEfficacy of inspection
Unintended use Volumes may not be trackedPlanting and harvest times Pest-free time periods/reduced host susceptibility Reduce or prevent infestation

Cultivar selection Host status/resistance Reduce or prevent infestationPost-harvest handling Washing, waxing, brushing, bathing, culling, etc. Reduce or prevent infestation

Processing Peeling, baling, heating, cooling, cooking, milling, etc. Reduce or prevent infestation

Packing and safeguarding Prevention of reinfestation Prevention of reinfestation Treatments Commodity tolerates various treatments High mortality

Shipment Mode of shipments includes treatment potential (e.g., cold treat in transit) Potential mortality

Inspection Commodity is easily inspect/tested Detect infestation

Intended use Devitalization Prevent establishment Volume of exports**(proposed by exporting country) Note whether or not increased volumes beyond originally requested volume will affect overall risk Potentially increase risk**Conducting Pest Risk Assessment in PPQ Process 10: Risk mitigation notes

2-73 Guidelines for Plant Pest Risk Assessment ofImported Fruit & Vegetable Commodities 08/2012-1 Table 2-5. Examples of the type of pest in formation useful for risk managers.

Information relevant to risk mitigation Potential mitigations Anticipated effect or impact Uncertainty (level and source)

Pest: include a section for each actionabl e pest or group pests as appropriatePest biology (feeding, reproduction, development) In-field pest management practices Reduce or prevent infestation Lack of specific data Conflicting data
Variable data Variability of pest (e.g., biotype or strain differences)Availability of technologySuitability of technologyUse of proxy species for treatments Efficacy of detection Unknown organisms Seasonality Time of harvest or shipping (e.g., when the pest is not active) Reduce or prevent infestation

Host specificity Resistant cultivars, non-host status Reduce or prevent infestation Susceptibility (orresistance) to treatments Pre-shipment, intransit, or post-entry treatments Reduce or eliminate infestation

Distribution (geographic, temporal) Restrictions on timeof year or destinations of imports Prevent establishment

Climate suitability Restrictions on timeof year or destinations of imports Prevent establishment

Environmental resistance or susceptibility Various types of shipping conditionsor post-harvest handling Reduce infestation

Detectable/testable Field trapping, reliability of pre- orpost-entry inspection Detect infestation

Presence of hitchhikers Inspection Detect infestation

Role of vectors Determine presence or absence of vectors in the UnitedStates by surveillance Reduce establishmentConducting Pest Risk Assessment in PPQ Process 10: Risk mitigation notes

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-74 Table 2-6. Example reporting for the pathway/commodity combination of Jordan bean.

Relevant section of risk assessment Information relevant torisk mitigation Potential mitigation Anticipated effect or efficacy Uncertainty (level and source)

Scope, Risk Element A1 Production
areas Field management of pests in thatcountry usually implements IPM programs, which includes biological control. Some reduction in pest prevalence, particularly external feeders. Medium high uncertainty, since specific controls are not listed. Scope, Risk Element A1 Planting and harvest times n/a n/a n/a

Scope, Risk Element A1 Cultivar selection n/a n/a n/a

Scope, Risk Element A2 Post-harvest handling Beans need to be intact, fresh appearance, clean (in particular freefrom any impurity or any visible chemical trace), free from foreign smell or taste, free from all abnormal external moisture, and sufficient size. The state of the product must be such as to enable it to withstand transport and handling. Some removal of external pests; anticipate a medium level of efficacy for this measure, but itwould be insufficient alone. Medium high certainty that this measure is effective for removing most external pests.

Scope, Risk Element A2 Processing n/a n/a n/a

Scope, Risk Element A2 Packing and safeguarding Standard packinghouse procedures: 1) The contents of each package must be uniform and contain only beans of the same origin, variety, and quality. 2) Packaging must be of such a kind as to ensure that the beans are properly protected; any paper or other material used inside the package must be new and harmless to human food; and when printed matter is used the printing must be on the outside only so as not to come into contact with the product. Each package must be legibly and indelibly marked on the outside with data for 1) Packer and dispatcher identification: name, address or code mark; 2) Nature of the productdescription: type (fresh beans, runner beans, and fine beans) or variety; 3) Product origin: district or national, regional or local, and trader name; 4)Commercial specification description: class, sizing, and classification; and 5) Official control mark. Protection againstre-infestation postpackaging



### — generally highly effective at preventing an increase in risk. Medium high certainty that this measure is effective forpreventing re-infestation by pests.

Scope, Risk Element A3 Shipment n/a n/a n/aConducting Pest Risk Assessment in PPQ Process 10: Risk mitigation notes

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Scope, Risk Element B2 Import timing n/a n/a n/a

Scope Treatments n/a n/a n/a Scope Intended use Beans are intended for consumption. It is possible, however, that beans could be used for planting. Low increase in risk possible if beans were to be planted and are viable. High uncertainty



### — data to support or refute potential risk are not available.
Scope Volume of exports** n/a n/a n/a

Variable Inspection n/a n/a n/a Variable Other n/a n/a n/a Table 2-6. Example reporting for the pathway/co mmodity combination of Jordan bean.

Relevant section of risk assessment Information relevant torisk mitigation Potential mitigation Anticipated effect or efficacy Uncertainty (level and source)

Table 2-7. Example reporting for the pest Dacus ciliates (Tephritidae).

Relevant section of risk assessment Information relevant torisk mitigation Potential mitigation Anticipated effect or efficacy Uncertainty (level and source)

Risk Elements A1, A2, A3 Pest biology n/a n/a n/a

Risk Elements A1, A2, A3, B2 Seasonality **See climate suitability. n/a n/a

Risk Element A1 Host specificity This species of fruit fly is primarily associated with cu curbits. Beans mayonly be a conditional host for this species—i.e., given high population pressure and proximity to cucurbit hosts. This may reduce the prevalence of the pest in the commodity. Reduced prevalence of the pest in the commodity—in combination with a treatment, low prevalence is likely to be sufficient to manage risk for this pest. 

### Medium low— further information on host status (e.g., experimental and field data on whether beans are a natural host for this species would reduce uncertainty.Conducting Pest Risk Assessment in PPQ Process 10: Risk mitigation notes

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 2-76

Risk Element B1 Distribution In combination with host status, the prevalence of this pest may be low in commercial bean production (depending on proximity to other host material and other environmental conditions). Surveillance records mayinform as to whether this pest is present in sufficient numbers to present a risk in commercially produced beans. Surveillance to demonstrate the prevalence of the pest will not reduce risk in itself but will provide supportingevidence in making determinations of host status (e.g., conditional host status) and willindicate if the population is lowenough to be effectively treated with treatments such as cold treatment. n/a

Risk Element B2 Climate suitability Importation of beans from Jordan during winter months would reduce survivability of this pest if infested beans were imported. Reduce likelihood of establishment since this species is a subtropical pest. Medium low.

Risk Elements B1, B2 Environmental resistance or susceptibility n/a n/a n/a

Scope Presence of hitchhikers n/a n/a n/a

Variable Detectable/ testable n/a n/a n/a

Variable Susceptibility or resistance to treatments Fruit flies in the family Tephritidae aresusceptible to many types of treatments including cold treatment andirradiation. In combination with conditional host status, a treatment wouldbe sufficient to manage risk associated with this pest. Reduce risk to an acceptable level for this pest. Medium low uncertainty--specific treatments for this pest may not exist, in which case proxy treatments may be necessary. Variable Role of vectors n/a n/a n/a Variable Other n/a n/a n/a Table 2-7. Example reporting for the pest Dacus ciliates (Tephritidae).

Relevant section of risk assessment Information relevant torisk mitigation Potential mitigation Anticipated effect or efficacy Uncertainty (level and source)08/2012-1 Guidelines for Plant Pest Risk Assessmentof Imported Fruit & Vegetable Commodities 3-1 

### Section 

# 3 Supplements and References

Supplement 1: WTO Disputes The SPS Agreement contains provisions for settling disputes between Members in cases where Members conte nd that another’s measures are not consistent with the Agreement. To date, there have been six dispute settlement cases related to the SPS Agreement, and in each case, risk analysis has played a prominent role. The cases are:
 The Variety Testing Case (the United States vs. Japan)  The Hormones Case (the United States and Canada vs. the European Communities)  The Salmon Case (Canada vs. Australia)  The Fire Blight Dispute (theUnited States vs. Japan)  The Fire Blight Dispute (N ew Zealand vs. Australia)Supplements and References Supplement 1: WTO Disputes

08/2012-1 Guidelines for Plant Pest Risk Assessmentof Imported Fruit & Vegetable Commodities 3-2 

###  The GMOs Case (the United States and Canada vs. the European Communities)

This section provides a brief summary of five of those cases, including a description of key SPS princi ples relevant to each case.

The Variety Testing Case (the United States vs. Japan)
Measure at issue. Japan’s requirement to test each variety of certain agricultural products (apples, cherries, peaches, walnuts, apricots, pears, plums, and quinces) for th e efficacy of treatment against codling moths. The United States claimed that it was not nece ssary to test each variety of a fr uit for the efficacy of the treatment. In this case, the issue of scientific ju stification was the key SPS principle bein g tested. Members have two options to show that their measures are bas ed on science. They may either:  base their measures on international standards or  base their measures on scientific risk assessment. Panel findings. The variety testing requirement vi olated Article 2.2 since there was no rational relationship between the scientific evidence submi tted by Japan and the measure. The exception provided in Article 5.7 did not apply. Japan invo ked this article, which allows Members to take provisional measures where scientific information is insufficient. However, the Panel found no evidence that Japan had actively sought to obtain additional information in order to review its measure within a reasonable period of time, as required by Article 5.7. The variety testing requirement violated Ar ticle 5.6 since it was more trade-restric tive than required to achieve Japan’s appropriate level of protection. The Panel was unable to rule on product-by-product testing, an alternative proposed by the United States, since it did not have sufficient evidence to decide whether this method achieved Japan’s appropriate level of protection. But the Panel considered another testing method related to sorption levels as a less trade-restrictive alternative.
The measure violated Article 7 and Annex B. The Panel f ound the variety testing requirement should have been published although the requir ement was not mandatory. Appellate body findings. Upheld the Panel’s finding on Article 2.2 that the measure was not based on science. Upheld the Panel’s finding on Article 5.7, and noted that t he length of the “reasonable period of time” had to be established on a case-by-case basis. Reversed the Panel’s finding on Article 5.6 regarding determination of sorption levels. The alternative measure had not been proposed by the United States, which had the burden of proof. Upheld the Panel’s finding on Article 7 and Annex B, agreeing that the measure should have been published.Supplements and References Supplement 1: WTO Disputes

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The Hormones Case (the United States and Canada vs. the European Communities)
Measure at issue. An EC (European Communities) ban on imports ofbeef from cows treated with hormones [oestradiol 17ß, progesterone and testosterone , trenbolone acetate (TBA), zeranol, and melengestrol acetate] for growth-promotion purposes. The EC claimed the ban was necessary for food safety; the United States and Canada claimed there was no evidence of harm to human health. In this case, the key principles being tested were “harm onization” (basing measures on international standards) and/or technically justifying measures which deviate from standards (through risk assessment). It is important to note that the encour agement to use international standards does not mean that these constitute a floor or a ceiling on nati onal standards. National measures do not violate the SPS Agreement si mply because they differ from international norms. According to Article 3 and Article 5 of the SPS Agreement, Members are permitted to adopt SPS measures that are more stri ngent than the rele vant international stan dards or adopt SPS measur es when international standards do not exist, provided the measures are  based on scientific risk assessment,  consistently applied, and  not more trade restrictive than necessary. Panel findings. The EC measure violated Article 3 on harmonization. Although international standards existed for five of the six hormones in question, the EC measure was not based on these standards; it reflected a higher level of protection and was not justified by a risk assessment, as required by Article 3.3. The EC ban was not based on a risk assessment, and violated Ar ticle 5.1. The EC’s scientific studies on five of the hormones did not support the ban on hormone-treated meat. The EC measure violated Article 5.5, because the level of protection sought for hormone-t reated meat was higher than required in comparable situations; these differences were ar bitrary or unjustifiable, and resulted in discrimination or a disguised restriction on trade. In particular, in contrast to the ban on hormones for growth-promoting purposes, the EC permitted higher levels of the same naturally occurring ho rmones in untreated meat and other foods; the use of the same hormones for therapeutic and herd management purpos es; and the use of other grow th promoters (such as the anti-microbial carbadox and olaquindox, known to be carcinogenic) in swine production. The EC had not invoked Article 5.7, which allows precaution ary measures to be taken on a provisional basis, but rather the “precautionary principle” in general. The Panel found that invoking the “preca utionary principle” did not override a country’s obligations under the SPS Agreement. Appellate body findings. Agreed with the Panel’s finding that since t he EC measure reflected a higher level of protection than the international standard and was not justified by a risk assessment, it violated Article 3. Confirmed the Panel’s finding on Article 5.1 that there wa s no rational relationship between the measure and the scientific evidence submitted on five of the hormones, and found that there was no risk assessment at all for the sixth hormone (melengestrol acetate). Reversed the Panel’s findings on Article 5.5. The Appella te Body considered that there was a fundamental difference between added hormones and naturally-occurring hormones in me at and other foods, and th at the therap eutic use of hormones involved closer supervision and control. Although the Appellate Body agreed that the difference between a ban on hormone-treated beef and the use of growth promoters in swine production wa s arbitrary, it did not consider that this resulted in discrimination or a disguised restriction on trade. Upheld the Panel’s finding on the use of precau tion and its relationship with Article 5.7. Implementation/“retaliation”. When the EC was unable to implement by the May 13, 1999 deadline, the United States and Canada sought the right to retaliate against the EC in the amou nt of US$202 million per year and CDN$75 million per year. The arbitrators found the appropriate level to be US$116 million and CDN$11.3 million per year, respectively.Supplements and References Supplement 1: WTO Disputes

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The Salmon Case (Canada vs. Australia)
Measure at issue. Australia’s ban on importation of fresh chilled orfrozen salmon, allegedly to protect the domestic salmon population from a number of di seases. Canada claimed that salmon im ported for human consumption was very unlikely to lead to the intr oduction of these diseases. In this case, the key principles being tested were “harm onization” (basing measures on in ternational standards) and or technically justifying measures which deviate from standards (through risk assessment). Panel findings. The import ban violated Article 5.1, because it was not based on a risk assessment. Australia had carried out a risk assessment for ocean-caught Pacific salmon, but the Panel found no rational relationship between the measure and the risk assessment. For t he other types of salmon, no risk assessment had been carried out. The Panel considered that the measur e prohibiting imports of fresh chilled and frozen salmon could also be described as a requirement that the salmon be heat-treated.
The Australian measure violated Article 5. 5, because the level of protection sought for salmon was much higher than in comparable situations; these differences were arbitrary or unjustifiable, and resulted in discrimination or a disguised restriction on trade. In partic ular, there were no restrictions on imports of frozen herring for bait; and there were few restrictions on imports of live ornamental fish. The ban on salmon was more trade-restrictive than required to achieve Australia’s appropriate level of protection, and therefore violated Article 5.6. Appellate body findings. Reversed the Panel’s finding that the ban on the other types of salmon was not based on a risk assessment, because the Panel made the finding bas ed on the heat-treatment requ irement. It found, however, that Australia’s risk assessment on ocean-caught Pacific salmon was not a proper risk assessment in the sense of the SPS Agreement, and the b an therefore violated Article 5.1. It upheld the finding th at no risk assessment had been carried out for other types of salmon. Upheld the Panel’s finding on Article 5.5, that the higher level of protection on salm on resulted in discrimination or a disguised restriction on international trade. Reversed the Panel’s findings on Article 5.6 because it was based on the heat-treatment requirement, and not on the import ban. Article 21.5 (Compliance) Panel findings. Australia had failed to comply by the deadline set by the arbitrator because its new measure on salmon took effect on July 19, 1999, and new measures on other fish (to comply with the consistency requirement) were phased in at later dates. The requirement that salmon be in a pa rticular consumer-ready form was not based on a risk assessment, and violated Article 5.1. The definition of consumer-ready product was more trade-re strictive than required, and thus violated Article 5.6.Supplements and References Supplement 1: WTO Disputes

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The Fire Blight Dispute (the United States vs. Japan)
Measure at issue. Japan's set of requirements on apples from the Un ited States, including that they come from an orchard free of fire blight, surrounded by a buffer zone, under go at least three annual inspections, chlorine treatment, etc. in order to prevent the entry of Erwinia amylovora , the bacteria that causes fire blight, into Japan. The United States claimed that there was no evidence that mature, sympt omless apples could serve as a pathway for the disease. In this case, the key principles being tested were “harm onization” (basing measures on in ternational standards) and or technically justifying measures which deviate from standards (through risk assessment). Panel findings. Japan's measure, the set of requirements taken as a whole, violated Article 2.2 because it was maintained without sufficient scientific ev idence that apple fruit could serve as a pathway for the entry, establishment or spread of fire blight. The Panel considered the risk from mature, symptomless apples, the U.S. export product, and the risk that something other than mature, symptomless apples might be inadvertently or illegally shipped. The exception provided in Article 5.7 did not apply. This was not a situation in which sufficient scientific evidence did not exist, rather, there was a wealth of sci entific evidence regarding fire blight but it did not support Japan's measure. Japan's measure violated Article 5.1 because it was not ba sed on a risk assessment appropriate to the circumstances. Japan's pest risk assessment was not suffic iently specific regarding the risks of entry, spread or establishment through imported apples as opposed to other possible pathways, nor did the risk assessment evaluate the likelihood of entry, establishment or spread through apples. Furthermore, Japan' s risk assessment failed to evaluate the risk according to the SPS measures which might be applied, but ra ther considered only the existing measures. The Panel exercised judicial economy and did not rule on an alleged claim that the measure was more trade restrictive than necessary in violation of Article 5.6. The Panel found t hat the United States had failed to make a prima facie argument that the measure had not been notified and was in violation of Article 7 and Annex B. Appellate body findings. The Appellate Body upheld the Panel's findings with respect to violations of Article 2.2 and 5.1, as well as with regard to the inapp licability of Article 5.7 in this situation. The Panel's findings on Article 7 and Anne x B were not appealed. In addition, the Appellate Body ruled that the Panel had the authority to make findings and draw conclusions with respect to all apple fruit from the United States, and not just with respect to mature, symptomless apples as the United States claimed. The Appellate Body furthermore rejected an argument that the Panel had failed to objectively assess the evidence before it regarding the likeliho od of completion of the last stage of the pathway. Article 21.5 (Compliance) Panel findings. Japan breached Article 2.2 of th e SPS Agreement by maintaining the compliance measure at issue without sufficient scientific evidence. Japan violated Article 5.1 of the SPS Agreement because the phytosanitary measure was not “based on an assessment, as appropriate to the circumstance s, of the risk to [...] plant life or heal th” in Japan because Japan relied on uncorroborated new studies that do not s upport the conclusion that imported apples could spread fire blight. If the United States only exported matu re, symptomless apples, the alternative measure proposed by the United States would meet the requirements of Article 5.6 as a substitute to Japan's current measure.Supplements and References Supplement 1: WTO Disputes

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The GMOs Case (the United States and Canada vs. the European Communities)
Measure at issue. Alleged general EC moratorium on approvals of biotech products, EC measures allegedly affecting the approval of specific biotech products, and EC me mber State safeguard measures prohibiting the import/marketing of specific biotech products within t he territories of these member States. In this case, the issues of scientific justification, transparency, equivalence, and approval procedures were the key SPS principles being tested. In 2003, the United States requested th e establishment of a Panel to examine the EC’s 1998 alleged moratorium on the approval of biotech products, which the Un ited States claimed was restricting tr ade on food and agricultural products and was inconsistent with the SPS Agreement’s Articles 2, 5, 7, and 8. The United States alleged that there existed a moratorium on the approval of biotech products, which si nce 1998 had limited the num ber of products receiving approval in EC states. Additionally, so-called “safeguard measures” were in place in six EC Member states, prohibiting certain biotech products that had already been approved at the EC level. General EC moratorium. The Panel found that a general de facto mora torium on approvals of biotech products was in effect on the date of panel establishment, i.e., August 2003 . It was general in that it applied to all applications for approval pending in August 2003 under the relevant EC legi slation, and de facto because it had not been formally adopted. Approvals were prevent ed through actions/omissions by a group of five EC member States and/or the European Commission.
SPS Articles 5.1 and 2.2: The Panel found th at the EC decision to a pply a general moratorium was a decision concerning the application/operation of approval procedures, i.e., a procedural decision to delay final substantive approval decisions. It was not applied for achieving t he EC level of sanitary or phytosanitary protection and, henc e, was not an “SPS measure” subject to Articles 5.1 or 2.2. SPS Annex C(1)(a) and Article 8: The Pane l found that the general moratorium led to undue delay in the completion of the EC approval procedure conducted in respect of at least one biotech productat issue and thereby to the European Communities acting inconsistently with An nex C(1)(a) and, by implication, Article 8. Product-specific measures. SPS Annex C(1)(a) and Article 8: The Panel fo und that in 24 of the 27 product-specific approval procedures it examined, the procedure had not been completed without undue delay. In respect of these procedures, the European Communities had, th erefore, acted inconsistent ly with Annex C(1)(a) and, by implication, Article 8. EC Member State safeguard measures. SPS Article 5.1, 2.2 and 5.7: According to the Panel, the record did not indicate that there was insufficient evidence to conduct a risk assessment within the meaning of Article 5.1 and Annex A(4) for the biotech products subject to safeguard measures. As a re sult, Arts. 5.1 and 2.2 were applicable. In this regard, the Panel found that none of the safeguard measures at issue were based on a risk assessment as required under Art. 5.1 and defined in Annex A(4). By maintaining measures contraryto Article 5.1, the European Communities had, by implication, also acted inconsis tently with Article 2.2.Supplements and References Supplement 1: WTO Disputes

3-7 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 08/2012-1 Figure 3-1. Relevant findings of SPS disputes.Supplements and References Supplement 2: Plant Hardiness Zones Area and Population Analysis

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# Supplement 2: Plant Hardiness Zo nes Area and Population Analysis Plant hardiness zones represent areas of average annual minimum temperatures, illustrating where it is safe to plant plants without frequent cold damage. They are a component of phytosan itary risk analysis and are a useful tool for estimating potentialarea of impact for plan t pests. Using Geographic Information Systems (GIS), it is possi ble to determine the approximate area and population of the United States c overed by each hardiness zone, which allows for a more accurate risk estimate.
Global plant hardines s zones were created by ZedX Inc. for the North Carolina State University APHIS Plant Pest Forecast System (NAPPFAST) using methods described in Magare y et al. (2008). The zones were created at a grid resolution of 10 km using monthly data from the Climate Research Unit (CRU) and station data from the Daily Gl obal Historical Climatology Network (GHCN). Individual hardiness zone grid files for zones 1-13 were transferred into ArcInfo 9.2. The geo-tiff grid fi les were converted to polygons and the area in square miles was calculated usi ng the edit and summarize function. To estimate population by hardiness zone, county data containing 2005 census data was utilized from the ESRI US County Area Shapefile. Counties were manually assigned to a hardiness zone wh en they were estimated to be covered by 50 percent or more of that zone. P opulation information from the assigned counties was obtained usi ng the summarize function. Area was estimated for zones 12 and 13, which are present in Hawaii, but population for those zones was included in zone 11 using th e previously described methodology.
The plant hardiness zones for Puerto Rico, a commonwealth of the United States, were also analyzed using zone coverage of county areas to estimate area. Eight percent of the island was de termined to be in Zone 11 and 92 percent in Zone 12 ( Figure 3-2 ). The population of Puerto Rico, estimated to be 3.944,249 in 2007, was obtained from the CIA World Factbook (CIA, 2008). Area and population values for Puerto Rico were not included in the estimates for the United States.

Table 3-1. Estimated percentage of area and population of the United States by plant hardiness zones. Hardiness zones were generated using data from 1997-2006 (Magarey et al., 2008); population estimates were derived from 2005 census data at county level.

Plant hardiness
zone Estimated area in square miles Percentage of U.S.
area Population from 2005 census Percentage of U.S. population
1 199,053 5.6 94,942 0.03
2 130,616 3.7 15,490 0.01
3 206,116 5.8 1,172,840 0.04Supplements and References Supplement 2: Plant Hardiness Zones Area and Population Analysis

3-9 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 08/2012-1 Figure 3-2. Estimated percentage of area and population of the United States by plant hardiness zones. Hardiness zones were generated using data from 1997-2006 (Magarey et al., 2006); population estimates were derived from 2005 census data at county level.



### Prepared by: 

### D. Borchert, Risk Analyst, USDA-APHIS-PPQ-CPHST-PERAL
R. Magarey, Senior Research Assistant, NCSU-CIPM 4 456,289 12.9 9,142,737 3.1
5 470,679 13.3 22,520,330 7.5 6 677,225 19.2 65,924,988 22.1
7 536,148 15.2 68,715,477 23.0
8 505,586 14.3 51,178,543 17.1
9 315,856 8.9 59,946,996 20.1
10 31,993 0.9 13,257,280 4.4
11 4,712 0.1 6,734,768 2.3
12 1,119 0.03 Included in 11 n/a
13 1,319 0.04 Included in 11 n/a Totals 3,536,711 100 298,720,176 100 Table 3-1. Estimated percentage of area and population of the United States by plant hardiness zones. Hardiness zones were generated using data from 1997-2006 (Magarey et al., 2008); population estimates were derived from 2005 census data at county level.

Plant hardiness
zone Estimated area in square miles Percentage of U.S.
area Population from 2005 census Percentage of U.S. populationSupplements and References Supplement 3: Host Status

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 3-10 

# Supplement 3: Host Status
Host status issues in PRAs Pests can be associated with host plan ts in different ways, depending on the biology of the host and pest, and the e nvironment in which pests and hosts interact. The nature of the relationship th at a pest has to a host can impact the ability of the host commodity to be a s ource of viable prop agules of the pest that can lead to its entry and establishment in the PRA area. This supplement is meant to provide a conceptual framew ork for analyzing host status and a decision tool to evaluate not only host status as an intrinsic biological property of a pest as it interacts with a host, but also attempts to account in part for the likelihood of the pest to move on the commodity in a form and manner that would allow its introduction. Or more simp ly put, analysts are encouraged to look carefully at host status, and also determine whether or not the infested/ infected commodity will be a source of the pest, enabling it to become established. This guide attempts to increase the transparency of the process of evaluating host status for new risk analys ts and our stakeholders, as well to improve the consistency of our risk assessments. 

## Scope and purpose Determining the status of hos ts with respect to pests is one of the central pieces of information needed to conduct PRA. The determination of host status can have major impacts on phytosanitary measures required for importing and exporting commodities, as well as domestic level d ecisions and actions (e.g., eradication programs, surveys, etc.). In commodity- based PRAs (e.g., Q56 PRAs for importation of fruits and vege tables for consumption), the issue of host status influences the PRA in four key places:
 qualitative likelihood or probability th e pest will follow the pathway for entry on the host,  qualitative likelihood or probability th e pest will find suitable hosts after entry and establishment,  qualitative likelihood or probability that the pest can spread, andSupplements and References Supplement 3: Host Status

3-11 Guidelines for Plant Pest Risk Assessment ofImported Fruit & Vegetable Commodities 08/2012-1 

###  the extent of economic impact (on hosts in the importing country) that the pest is likely to have. Because host status can aff ect the estimated level of risk for a pest (through the four likelihoods identified above), it is critical that host status be defined as accurately as possible in the PRA.
There are many diverse source s of information availabl e that provide lists of hosts for pests. Some of these sources s imply associate the pest with a host(s) in a very general sense, while other s ources of information provide a detailed description of the relationship of the pe st to the host(s). Likewise, information sources may describe different types of hosts, according to th e status of that host to the pest. This terminology is not harmonized and can be interpreted in many different ways. The di verse terminology and the di versity of descriptions of host- pest interactions may be ex tremely difficult to interpret when conducting PRA.
This paper provides guidelines for inte rpreting information regarding pesthost interactions for the purpose of PRA, and furthermore provides suggested terminology that should be usedto describe the status of host(s) with respect to pests, or in defining the host-pest interactions. 

## Key issues Host status is, in many cases, very cl ear for well-documented pests for which there is agreement in the sc ientific literature. However, there can sometimes be considerable controversy in interpreti ng information, even for pests that are well understood. Host status requires regular revi ew for several reasons:
 errors in the literature or in databases and compendia (e.g. inaccuracy due to incorrect citations, incorrect interpretations). See Appendix A: Recommendation for Prunus persica vari eties to be considered non-hosts for Bactrocera cucurbitaeon page 3-27 for an example of this issue.  host status of a commodity may be variable depending on host and pest biology (e.g., imprecision due to changes in host status depending on season, ripeness, variety, geographic area, population density). See Appendix A: Recommendation for Prunus persica varieties to be considered non-hosts for Bactrocera cucurbitaeon page 3-27 for examples.  host status is unclear (lack of data in the literature, conflicting information, or only experimental hos ts are described but lacking field data). See Appendix A: Recommendation for Prunus persica varieties to be considered non-hosts fo r Bactrocera cucurbitaeon page 3-27 for examples.Supplements and References Supplement 3: Host Status

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 3-12 

###  cases where a pest is associated with a commodity but may not be feeding on that commodity (e.g., snai ls on tile, hitchhikers or contaminating pests; alfalfa weevil on pomegranate).



## TerminologySupplements and References Supplement 3: Host Status

3-13 Guidelines for Plant Pest Risk Assessment ofImported Fruit & Vegetable Commodities 08/2012-1 

### Background 

### An array of terminology describes host- pest interactions in the scientific literature, but the terms are not used c onsistently nor are they harmonized and is difficult to interpret with regard to the level of risk the specified interaction may present. Examples of terms found in the literature include, but are not limited to, those found below.

These different terms imply information about the relationship of the pest to the host, and therefore, correspondingly, the level of risk associated with the host status but do not define the exact pa rameters for any of such relationship. For instance, terms such as natural, field, preferred, and primary host imply that the pest can be found on the host plant in the field (or other production system) and that the pest can surviv e and perpetuate itself under natural growing conditions for the host. Most work on host status has been done on fruit flies (Tephritidae), but host status concerns also occur with other groups of pests (including other arthropods and plant pathogens).
For example, ISPM No. 11 (IPPC, 2004a) talks about hosts th at are capable of sustaining pests “under natu ral conditions.” This woul d not generally include laboratory or experimental hosts. Under certain condi tions or circumstances, plants that are susceptible to a given pest in the laboratory may remain free from infestation or in fection under natural condi tions. Plants may be susceptible only at a certain life stage (fruiting, flowering, etc.) when the pest is not present and active. Physical features of the plant, such as hairs or wax layers, may prevent vectors or wate r droplets containing inoculum from contacting the plant surface. Experiment al or laboratory inoculation or infestation methods can allow infestations or infections to occur that do not EXAMPLE host

field host

natural host
primary host
preferred host

commercial host
regulated host
reproductive host

conditional host

conditional non-host experimental host
laboratory host
secondary host
non-preferred host

wild host

occasional host

minor host
poor host

rare host

natural non-host non-host

host of unknown significance

alternate host

latent host

indicator host

local lesion host
diagnostic host

associated hostSupplements and References Supplement 3: Host Status

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### occur in nature (e.g., mechanical inoc ulation, or dodder infection of a plant with a virus or phytoplasma normally vect ored by an insect that does not feed on that plant; insect pests feeding on pl ants when lacking another food source).
National, regional, and inte rnational organizations have recognized the need to harmonize methods for determination of, and terminology related to, host status. This is important in conducting PRA, pr oposing risk mitigation options, communicating to domestic and forei gn stakeholders, and in developing regulations and strategies to address pests. Two regional organizations (Asia Pacific Plant Protection Organization or APPPC, and North American Plant Protection Organization or NAPPO) have developed regional standards on host status, and the IPPC has a produced a draf t standard on host status for fruit flies based largely on the two regional standard s. The standards provide guidance to countries on how to determine host status , and further define categories of host status.Supplements and References Supplement 3: Host Status

3-15 Guidelines for Plant Pest Risk Assessment ofImported Fruit & Vegetable Commodities 08/2012-1 

### Recommendation 1: Host status terminology 

### Consistent with the NAPPO RSPM No. 30 [ Guidelines for the Determination and Designation of Host Status of a Fruit or Vegetable for Fruit Flies (Diptera: Tephritidae) ] (NAPPO, 2008), the following term s should be used for hosts with regard to pests thatfeed on or infect hosts.

For the purposes of this document, a T ype 2 host (conditional host) can also be used to describe hosts that have been experimentally infested (or infected) but for which field data or other evidence is lacking. The above terms may apply in one or more areas within the range of the pest, which should be specified.
In some cases, pests may be associated with a host or other material, but not actually feeding on or infecting th e host material. Examples of such associations include:
 snails that adhere to tiles.  pupae in packing boxes.  pests that attack parts of the host plant other than fruit, but that “hitchhike” with the fruit. In these cases, the host material is not a food source, but may serve as a substrate for the pest to move in trad e. The most applicable term for such materials (including fruit, boxe s, or other material where the pest is present but is not feeding / infesting the fruit or vegetable) is “fomite” (Type 4 host).

Type 1 host (natural host). A plant species that becomes infested or infected by a plant pest in nature under natural conditions (e.g., natural, cultivated an d/or unmanaged plants) and the plant pest is sustained on that plant species. No other trials are necessary to confirm host status. Type 2 host (conditional host). A plant species that is only a host or a non-host under defined narrow range of conditions, respectively (e.g., host variety, stage of host maturity, other physiological conditions of the host, environmental, ecol ogical or other physical conditions). Type 2 Hosts can be considered:  Type 2a. A non-host becomes a host (example: lemons become a fruit fly host under heavy population pressure and drought; artifici ally inoculated laboratory hosts for some plant viruses, viroid s, or phytoplasmas).  Type 2b. A host becomes a non-host (example: avocados are generally a fruit fly host, but ‘Hass’ avocados are a non-host for some species of fruit flies). Type 3 host (natural non-host). A plant species that does not become infested or infected by a plant pest under natural conditions (e.g., natural, cultivated and/or unmanaged plants) and the plant pest is not sustained on the plant species, nor can the pe st survive, perpetuate itself or spread. Type 4 host (fomite). An object or material (including a harvested plant part) that may be contaminated with a pest and that could tr ansmit that pest from one place to another.Supplements and References Supplement 3: Host Status

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 3-16 

## Evidence and information sources

Background 

### There are many sources of informati on for host status, including original refereed scientific literature, various types of compendia, scientific reviews, interception records, NPPO records, and technical reports, as well as other sources that are less relia ble (e.g., websites, news articles, etc.). Host records from reputable refereed sc ientific publications are c onsidered to be the most reliable. Whenever possible, the orig inal source of information should be checked and referenced for any host record, even for pests that are well understood. In some cases, this may involve going back in the literature a hundred years or more. In cases where the original reference(s) cannot be obtained, the analyst should trace back the information as far as possible.
Various types of compendia are often av ailable and very us eful sources of information. However, care sh ould be taken in interpreting information in such compendia, particularly with regard to host status (as well as geographic distribution). The problem arises becau se original evidence is sometimes misinterpreted when it ge ts added to different comp endia, but once a reference is established, it becomes ingrained in th e literature and is rarely questioned or validated.
Interception records are also common sour ces of information for associating a pest with a host. In cases where there are repeated interceptions, these records can provide a useful basi s for judging host status. However, single or a few interception records, especially those onbaggage (vs. commercial fruit) should be interpreted with caution. In th e absence of any other corroborating information, single interception records ar e generally not indicative of a hostpest association.
Figure 3-2 provides a discussion of the types of evidence that is used for determining host status, and the corresponding (relative) level of reliability. In general, information from well-known, peer-reviewed scien tific journals and identifications done by taxonomic specialist s are viewed to be the highest in reliability and should be considered a ccordingly. For pathogens in particular, Koch’s postulates should also be considered in determining host status of the plant species. When a pathoge n is associated with a dis eased plant, proof of its role as the cause of the disease may beestablished by completing several steps known as Koch’s Postulates (after the 19th century bacteriologist, Robert Koch).
Koch’s Postulates to prove pathogeni city are (definitions adapted from Shurtleff and Averre , 1997; Falkow, 2004)Supplements and References Supplement 3: Host Status

3-17 Guidelines for Plant Pest Risk Assessment ofImported Fruit & Vegetable Commodities 08/2012-1 

### 1. Consistent association. Consistent association of a suspected causal agent with a disease.
2. Isolation. Isolation of the pathogenic agent an d its growth in pure culture. This may be difficult with some kinds of pathogens, e.g., obligate parasites, non-culturable organisms, but spec ialized methodologies, transmission studies, or consistent association withother isolated molecular markers can contribute to identifying and charac terizing non-culturab le pathogens. For example, some plant viruses can be isolated by means of transmission to experimental hosts or cells by insect vectors, parasitic plants or grafting, then used to re-infect healthy plants of the original host species. Reinoculation: Inoculation of healthy plants with prospective pathogen must produce the same symptoms as the initial disease descri bed. Re-isolation: The pathogen must be re-i solated from the inoculated, diseased plant and identified as being identical to the original pathogen.
Recommendation 2: Interpretation and evaluation of evidence related to host status

Table 3-2. Reliability of evidence. Criteria fo r evaluating the reliability of evi dence from most reliable (1) to least reliable (8). Table adapted from M. Hennessey, unpublished, and ISPM No. 8, Determination of pest status in an area (IPPC, 1998). A=ar thropod; P=Pathogen. Type of evidence

Host status determination method How recorded Pest/plant collector Pest/ plant identifier Location and date precisionRelative level of reliability of evidence 1 A Reproductively viable adult reared out of natural infestation on plant or from commercial orcommercial grade consignment in trade (if origin traceable). NPPO record (e.g.,, manyinterception records); refereedpublication Taxonomic specialist Discriminating biochemical,serological, or molecular diagnosis Delimitingor detection survey P Koch’s postulates comple ted with cultures/isolates from natural infection on plant or from commercial or commercial grade consignment in trade (if origin traceable).

2 A Viable adults from forced field infestation of green or commercial harvestable grade plant. Refereed scientificor technical journal Professional specialist Specimenmaintained in an officialcollection; taxonomicdescription by specialist Other fieldor production survey P Koch’s postulates have not been completed, but the pathogen can be grown in pure culture and successful inocul ations made with, for example, single spore isolates (or equivalent for organisms other than fungi), resulting in development of the same symptoms.Supplements and References Supplement 3: Host Status

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 3-18 3 A Viable adults from lab infestation (choice ornon-choice) of green or commercial harvestable grade plant. Official historical record; State Extension Service Bulletin;plant disease clinic report; afew interception records Scientist Specimenin a general collection Casual or incidental fieldobservations, possible with no defined location or date. P Pathogen cannot be grown in culture, but successful inoculations can be made, for exampleby insect vectors, graft transmission, or parasitic plants (dodder) from naturally infected plant material to health y plants, resulting in development of the sa me symptoms. The pathogen is consistently associated with the disease in the host.

4 A Lab infestation of ground or non-commercial grade plant. Non-refereed scientific or technical journal orpublication Technician Description and photo Observation with/in products or byproducts;interception P Successful laboratory inoculations are made, for example, by mechani cal transmission, but only to experimental hosts, no evidence thatthe pathogen infects plants in nature, in cultivation, or production systems.
5 A Reproductively viable adult reared from ground, damaged, or non-commercial grade plant. Specialist amateurpublication Expert amateur Visualdescription only Precise location/ date unknown PRelative level of reliability of evidence 6 A Oviposition observed but no viable adults, pupae, larvae, or eggs in plant. Unpublished scientific or technical document Non-specialist Non specialist
P Plants produce symptoms characteristic of infection with specificpathogen, without anyconfirmation of the organism causing the disease. 7 A Plants produce general symptoms of a disease or infestation. Non-technical publication; periodical
or newspaper P

8 A Host status determination unknown. Unpublished personalcommunication Collector unknown Method ofidentification unknown Location and date unknown P Table 3-2. Reliability of evidence. Criteria fo r evaluating the reliability of evi dence from most reliable (1) to least reliable (8). Table adapted from M. Hennessey, unpublished, and ISPM No. 8, Determination of pest status in an area (IPPC, 1998). A=ar thropod; P=Pathogen. Type of evidence

Host status determination method How recorded Pest/plant collector Pest/ plant identifier Location and date precisionSupplements and References Supplement 3: Host Status

3-19 Guidelines for Plant Pest Risk Assessment ofImported Fruit & Vegetable Commodities 08/2012-1 

## Interpreting evidence to determine host status Background There are two levels in determining hos t status. The first level is collecting evidence on actual experime nts or data to establish host status. The second level is in interpreting the published data or other evidence to make a judgment as to what the host status is. As mentioned previously, numerous terms can be found in the scientific literature to desc ribe host status, but for the purposes of PRAs done for commodities, the terms T ype 1, 2, 3 and 4 hosts (natural host, conditional host, natural non-host, and fomite, respectively) should be used. Table 2 provides a list of terms used to describe host status and identifies, using the above terminology, how other term s found in the literature may be interpreted.
Guidance to researchers on determining hos t status is available, at least for fruit flies, in the two regional standards and in the draft IPPC standard identified previously. These documents outline the experimental designs that should be used in determ ining host status. They al so provide guidance on how to interpret results of various types of tests (e.g., laboratory testing, field samples, cage testing). When host status testing follows such protocols, it is relatively simple for risk analysts and regulators to make a determination on host status. However, in many cases, the available literature is based on experiments that have not followed specific prot ocols but that nonetheless identify the host status of plants. Furthermore, because the available evidence can be highly variable in quality, e xperimental design, and numerous other factors, risk analysts must make certain judgments about host status based on the available evidence.
The categories for natural host and natu ral non-host are often relatively clear and easy to interpret from th e literature. In cases where a pest can complete its life cycle and/or a population can be naturally sustained on that plant, or in other words, the pest can survive, multiply, and spread via an infected or infested plant part, then the host may be regarded as a “natural host.” In contrast, if a pest cannot complete its life cycle, and/or a population cannot be naturally sustained on a plant, then thatplant is considered a natural non-host.
Not surprisingly however, “conditional hosts” are the most difficult to understand or interpret, partic ularly with regard to the level of risk they may pose. A conditional host may be either a natural host that can be a non-host under specific conditions, or it may bea natural non-host that can be a host under specific conditions. The conditions th at affect whether a plant may be a host or not include:
 host variety,Supplements and References Supplement 3: Host Status

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 3-20 

###  physiological state of the host (including ripeness, life stage of pest on specific plant parts),  barriers to transmission of the pest (host to vectors, and vice versa),  geographic variations in pests (including strains or races) or hosts, and  environmental conditions (includi ng seasonality, drought, or other conditions). The risk analyst must make a judgmen t about the host status based on the quality of evidence and the type of evidence provided (e.g., field studies, laboratory studies, etc. See Recommenda tion 2), especially for Type 2 hosts. For Type 2 hosts, there must be spec ific evidence describing the exact conditions under which a plant becomes a host or non-host. Table 3-3 provides recommendations for host status descriptions.
Recommendation 3: Procedure for identifying host status in PRAs 

### Use Table 3-3 to determine whether a plant is a Type 1, 2 or 3 host. The first row shows the harmonized terminology that should be used. Subsequent rows show terms that may be occur in the literature and suggest how those terms should typically be interpreted. In examining evidence, Recommendation 2 should also be followed. Figure 3-3 provides a flow chart to aid in examining evidence and making a judgment as to host status.Supplements and References Supplement 3: Host Status

3-21 Guidelines for Plant Pest Risk Assessment ofImported Fruit & Vegetable Commodities 08/2012-1 Table 3-3. Recommended classification of definitions found in the literature for host status according to terminology for Type 1, 2, and 3 hosts; level of ho st associations and unce rtainty expected for the type of host status. For both association and uncertainty, these levels are estimated and generalized, and are intended for description purposes only. There maybe be cases where either association or uncertainty differ from what is listed here.

Continuum of host status from natural host to natural non-host

Type 1 host: natural host Type 2 host: conditional host 2a: host Type 2 host: conditional host

2b: non-host Type 3 host: natural non-host

Term Level ofassociation with the host Expected uncertainty Term Level ofassociation with the host Expected uncertainty Term Level ofassociation with the host Expected uncertainty Term Level ofassociation with the host Expected uncertainty

Host H, M C, MC Conditional host H, M C, MC, MU Conditional non-host L, N C, MC Non-host N C, MC

Field host H, M C, MC Experimental host M, L MU, U Experimental host M, L MU, U

Primary host H, M C, MC Laboratory host M, L MU, U Laboratory host M, L MU, U

Preferred host H, M C, MC Occasional host M MC, MU Poor host L MU, U

Commercial host H, M C, MC Secondary host H, M, L (MC), MU Unusual host L MU, U

Wild host H, M C, MC Minor host M, L C, MC, MU Rare host L MU, U

Non-preferred host M, L MC, MUSupplements and References Supplement 3: Host Status

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 3-22 

### In the case of fomites, there should be documented evidence that a pest is associated with the mate rial in question. This evidence can come from the scientific literature, NPPO reports, or other techni cal documents. One of the most common sources of evidence for pest association with a fomite is port interception records. Examples of fomi tes or pest association with fomites include:

EXAMPLE Commodity of plant origin: pest feeds on or infects plant, but not exported plant part; pest associat ed with plant but does not feed on or infect plant or exported plant part; pest intercepted with commodity, but no other documentation available (e.g., a true hitchhiker)
Commodity of non-plant origin: tiles/stone; vehicles/machinery
Material associated with the commodity: boxes containing plant parts; wrapping materials; packing materials or containers
Containers/conveyances: shipping containers; railway cars; ships and other vehicles

Other: soil; growing media; leaves, twigs, or other prohibited materialsSupplements and References Supplement 3: Host Status

3-23 Guidelines for Plant Pest Risk Assessment ofImported Fruit & Vegetable Commodities 08/2012-1 

## Relationship of host status to risk The level of pest association and uncertainty for Type 4 hosts (fomites) is variable, and depends on the type of pest , the type of association of the pest with the fomite, the potential for moving in trade or other means, the potential for mitigation (e.g., cleaning, removal of pe sts, treatments), and other factors. Therefore, fomites can only be addresse d on a case by case basis and general guidance on the level of risk pos ed by fomites is not possible.
For Type 1 hosts (natural hosts), the exp ected level of association of the pest with the host (i.e., that the pest is associ ated with the plant part of a particular species) will in most cases be high or at least medium , and the level of uncertainty will be relatively low (i.e ., certain, moderately certain). Likewise, for natural non-hosts, the level of association of a pest with the host will be negligible, with low uncertainty (i .e., certain, moderately certain).
There may be greater uncertainty whendetermining whether a Type 2 host (conditional host) can be a host or non-host. However, the determination that a Type 2 host is a non-host (e.g., Type 2b or a non-host under specific conditions) should only be made when there is low uncertainty (i.e., certain or moderately certain). If uncertainty is judged to be moderate or more than moderate, then a conservati ve interpretation of the data should be made and the host status should be determined to be a Type 1 host.

In all cases, the determination of hos t status can be accompanied by both a specified level of likelihood of as sociation (using the recommended terminology) and uncertainty. The specifi ed level of likelihood of association and the uncertainty are useful for maki ng judgments in PRAs as to whether a pest may be expected to follow a particular pathway.Supplements and References Supplement 3: Host Status

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## Examples, exceptions, and uncertainty Analysts should be aware that ther e are always exceptions or unusual circumstances that can affect host status. Perhaps one of the most well-known examples is that of lemons serving as a host of Medfly (the Mediterranean fruit fly). It was commonly understood that lemo ns were not a host of Medfly, until Medfly was intercepted in imported lem ons. In reviewing the evidence, it was determined that during an exceptionally dry year, and a year with an exceptionally high Medfly population, th e pests were ableto overcome the natural resistance of lemon fruit to Medfly, and populations were able to successfully develop on lemons. This si tuation, therefore, proved to be an exception to the conventional wisdom concerning the host status of lemons. Following are some additional exampl es of pests and types of hosts.

EXAMPLE Plum pox virus
Natural host range (Type 1 hosts): Prunus armeniaca, P. cerasifera, P. domestica, P. glandulosa, P. persica, P. insititia, P. spinosa, P. salicina, P. cera sus, P. avium, Juglans regia
Experimental hosts (Type 2 hosts): Capsella bursa-pastoris, Celosia argentea,Chenopodium capitatum, C. ambrosioides, C. foetidum, C. foliosu m, C. murale, C. quinoa, Cyamopsis tetragonoloba, Emilia sagittata, Gomphrena glob osa, Humulus lupulus, Hyoscyamus niger, Lupinus albus , Lycopersicon esculentum, Melilotus albus, M. of ficinalis, Nicandra physalodes, Nicotiana acuminata, N. benthamiana, N. bigelov ii, N. clevelandii, N. debneyi, N. glutinosa, N. megalosi phon, N. occidentalis, N. rustica, N. sylvestris, N. tabacum, Petuni a × hybrida, Physalis floridana, P. peruviana, Pisum sativum, Ranunculus arvensis, R. sardous, Senecio vulgaris, Sesbania exaltata, Sorbus domestica, Stellaria media, Trifolium pratense , T. repens, Vicia sati va, V. villosa, Zinnia elegans

EXAMPLE Anastrepha distincta (Peru citrus)
Literature (Norrbom and Kim, 1988) lists only laboratory and questionable reports of A. distinctaon citrus.

Based on this evidence, it was determ ined that this fruit fly species is not likely to be associated with commercial citrus for export (Type 3 host).Supplements and References Supplement 3: Host Status

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### Interception can be valuable in establis hing potential pathways, but data should be scrutinized carefully and used cautiously. EXAMPLE Monilinia fructigenain the United States
Guignardia citricarpa in Peru

EXAMPLE Sweet orange scab ( Elsinoë australis )
Quarantine pest that has been intercepted on citrus from Peru by APHIS on multiple occasions.
All interceptions were made from passenger baggage and ship’s stores or quarters. As such, the true origin of the fruit is difficult to determine.
The disease has been reported from surrounding countries and flights from some of these countr ies to the United States connect through Peru.Supplements and References Supplement 3: Host Status

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 3-26 Figure 3-3. Determination of host status for PRA based on scientific evidence.Supplements and References Supplement 3: Host Status

3-27 Guidelines for Plant Pest Risk Assessment ofImported Fruit & Vegetable Commodities 08/2012-1 

## Appendix A: Recommendation for Prunus persica varieties to be considered non-hosts for Bactrocera cucurbitae Current regulatory status. Peach ( Prunus persica ) is currently regulated domestically and internationally as a host of Bactrocera cucurbitae (melon fruit fly or MFF); however, nectarine (also P. persica ) is not regulated as a host of MFF. Peach and nectarine are the samespecies; the only difference is that nectarines are a smoothe d-skinned variety of Prunus persica lacking the typical velvety skin found on peaches.
Taxonomy of MMF

. This species has been described previously as Chaetodacus cucurbitae (Coquillet), Dacus cucurbitae Coquillet, Strumeta cucurbitae (Coquillet), and Zeugodacus cucurbitae (Coquillet). The current accepted name is Bactrocera cucurbitae (Coquillet).

Status of MMF in the continental United States. Although MFF has been long established in Hawaii, it is not established in the continental United States. It is periodically introduced and eradicated in California. It primarily occurs in parts of Asia and the Paci fic region, and sporadically in Africa.

Hosts of MFF. MFF primarily attacks plants in the family Cucurbitaceae (pumpkins, squash, gourds, cucumbers, me lons and related species). It can attack fruits and flowers, as well as occasionally stems and roots. There are numerous unconfirmed records on non-cucu rbit hosts and non-cucurbit hosts are considered to be uncommon.

Host status of Prunus persica varieties for MFF. There are very few reliable records of MFF infesting peach and no records of MFF infesting nectarines. White and Elson-Harris (1992) providethe following information “Other Hawaiian records are....peach ( Prunus persica )...(Harris et al., 1986b; Maehler, 1951; Nakagawaet al. 1968)” (pg 265).
When the original references are checked, neither Maehler (1951) nor Nakagawa et al. (1968) actu ally mention peach as a host of MFF. Harris et al. (1986) mentions that peaches were co llected in Hawaii to look for adult emergence; however, no adult MFF em erged from peach in any of the collections over a two-year period of the study. In the original Harris article, peach is listed as a “rare host” even though no flies have ever been collected from peach.
In White and Elson Harris (1992) in the “Useful plants and their associated tephritids” section, Prunus perscia is listed as an “unusual host” (pg. 473).
Back and Pemberton (1917) reared a single fly from peach in 1914. This is the only reliable record of MFF being associated with peach.Supplements and References Supplement 3: Host Status

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 3-28 

### According to a review by Liquido et al. (unpublished), MFF has never been collected from peach in any records between 1949 and 1991 in Hawaii. There are no other reliable records or scientific publications that conclusively show peach (or nectarine) serves as a host for melon fruit fly.

Recommendation. Based on the available scientific evidence, it is recommended that neither peach nor nectarine (e.g., any variety of Prunus persica ) be regulated domestically or in ternationally for melon fruit fly (Bactrocera cucurbitae ).

References 

### Back, E.A. and C.E. Pemberton. 1917. The melon fly in Hawaii. USDA Bulletin No. 491. GPO. Washington.

Harris, E.J., Takara, J.M., and Nishid a, T. 1986. Distribution of melon fly Dacus cucurbitae (Diptera: Tephritidae), and host plants on Kauai, Hawaiian Islands. Environmental Entomology, 15, 488-493.
Liquido, N., P.G. Barr and G.T. McQuat e. Unpublished. Host plants of melon fruit fly Bactrocera cucurbitae Coquillet (Diptera: Tephritidae)

Maehler, K.L. 1951. Notes and exhibiti ons (March 13, 1950). Proceedings of the Hawaiian Entomological Society, 14, 205-207.
Nakagawa, S., Farias, G.J. and Urgao, T. 1968. Newly recognized hosts of the Oriental fruit fly, melon fly and Mediterranean fruit fly. Journal of Economic Entomology, 61, 339-340.

White, I.M. and M. M. Elson Harris, 1992. Fruit flies of economic significance: their iden tification and bionomics. CAB International. Wallingford.Supplements and References Supplement 4: Evaluation of Evidence

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# Supplement 4: Evaluation of Evidence Separating uncertainty arising from the lack of knowledge from ratings is important; ratings are made based only on the available evidence, not the uncertainty associated with the eviden ce. For instance, a given element should not be rated higher if there is a lot of uncertainty; rather the rating should be assigned based on available evidence, but the high level of uncertainty should be noted.
The uncertainty associated with the av ailable evidence should be evaluating in terms of both its reliability and its applicability ( Table 3-4 ).
Reliability refers to how reliable the source of the information is in terms of the quality of the source, age of the sour ce, the methodology used, and the degree of consensus. The quantity of information available can also be used in evaluating resources. For example, many resources from lower quality sources that have the same conclusion may be mo re powerful in terms of certainty than a single reference from a higher quality publication source.
Applicability refers to how applicable the information is to your situation. In most cases, the risk rating should be based on evidence on how the pest is currently behaving in the situations that correspond to the PRA area. Since this information is not always availabl e, we must extrapolate and make assumptions, but emphasis s hould always be placed on how the pest behaves in the parts of the distribution most similar to the PRA area.

Table 3-4. Reliability of sources of info rmation from low to high.

Publication source Reliability Examples
1 Well-known/respected peer-reviewed journal (English language or translated into English Low None
ML Few or no original research papers; any found do not describe methodology OR methodology used is not widely accepted.
MH At least one original research paper with detailed description of methodological approach. Several original research papers without specified methodology. Multiple published review articles; articles cite independent (separate) sources of information. High Multiple original research papers with detailed description of the methodological approach(es) used; approaches are widely accepted.Supplements and References Supplement 4: Evaluation of Evidence

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 3-30

2 Obscure or less-wellknown/respected peerreviewed journals (English language or translated into English) Low No original research. Few or no review or summary articles.
ML Few or no original research papers; methodology may or may not be described.Multiple published review articles which may or may not cite independent (separate) sources of information.
MH Multiple original research p apers (with specified methodology). High Many original research papers (by multiple authors) that include a detailed description of the methodological approach(es) used; approaches are widely accepted; supported by other evidence.
3 Foreign language peerreviewed journals (abstract in English) Low Few or no review or summary articles. No supporting evidence found.
ML Multiple review articles research papers (which may or may not cite independent (separate) sources of information.
MH Multiple original research papers (methodology specified in abstract). High n/a
4 Other reputable sources (e.g., universities,experts, scientific societies) Low Few or no reports; t hose that are found may or may not be based on independent (different) information sources. No supporting evidence found.
ML Several articles and reports that may or may not have each been based on independent (different) information sources.
MH Many articles and reports; each article/reports is based on independent information; methodology is described. High n/a
5 Information from trading partner Low Evidence not well-documented or inconsistent with other sources; methodology not verified or it is not widely accepted.
ML Evidence well-documented and cons istent with other sources; methodology has either not been verified or it is not widely accepted.
MH Well-documented evidence that is generally consistent with other information; methodology verified and widely accepted. High Well-documented evidence; methodology verified and widely accepted; supported se veral other sources. Table 3-4. Reliability of sources of info rmation from low to high.

Publication source Reliability ExamplesSupplements and References Supplement 4: Evaluation of Evidence

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6 Scientific consensus Low May or may not have scientific consensus. Methodology may or may not be generally accepted. NPPO may or may not have experience with pest; if so, the evidence is may or may not be consistent with NPPO experience.
ML May or may not have scientific consensus. Any methodology described may or may not be generally accepted. NPPO may or may not have experience with pest; if so, the evidence is generally consistent with NPPO experience.
MH General consensus in scientific literature and other sources (but may include a few contradictory reports). Methodological approaches used are generally accepted.
Evidence consistent with NPPO experience w/ pest. High High consensus in scientific literature and other sources (no or practically no contradictory evidence found). Methodological approaches are widely accepted. Evidence generally consistent with NPPO experience w/ pest. Table 3-4. Reliability of sources of info rmation from low to high.

Publication source Reliability Examples

Table 3-5. Applicability of sources of in formation from low to high.

Publication information Applicability Examples

1 Species-specific data Low Species-specific data were limited; most of the species data wereapproximated or extrapolated from congeneric species, or other similar species.
ML Species-specific data were used; some of the species data were approximated or extrapolated from congeneric (or other) species known to behave similarly.
MH Species-specific data were used. High Data for both species were used.
2 Environment-specific data Low Environment-specific data were limited; no close proxy data was available; extrapolations were based on situations that may or may not be applicable.
ML Some environmental-specific data were used, but most were approximated or extrapolated from simila r situations (i.e., research conducted in the areas of comparable climate, on a closely related host).
MH Some environment-specific data were used, but at least some data were approximated or extrapolated from similar situations (i.e., research conducted in the areas of comparable climate, on a closely related host). High Environment-specific data were used.Supplements and References Supplement 4: Evaluation of Evidence

08/2012-1 Guidelines for Plant Pest Risk Assessment of Imported Fruit & Vegetable Commodities 3-32 Figure 3-4. Combining applicability and reliability of info rmation to obtain a certainty rating.Supplements and References Literature Cited

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# Literature Cited 7 U.S.C. § 7701-7786. 2000. Plant Protection Act, Title 7 United States Code § 7701-7786.

Andrews, C. J., D. M. Hassenzahl, and B. B. Johnson. 2004. Accommodating Uncertainty in Comparative Risk. Risk Analysis: 24 (5) 1323-1335.

Bale, J.S., Masters, G.J., Hodkinson, I. D., Awmak, C., Bezemer, T.M., Brown, V., Butterfield, J., Buse, A., Coulson, J. C., Farrar, J., Good, J.E.G., Hartley, R., Jones, T.H., Lindroth, R.L., Press, M.C., Symrnioudis, I., Watt, A. and Whittaker, J.B. (2002) Herbivory in gl obal climate change research: direct effects of rising temperature on insect herbivores. Glob Change Biol 8: 1–16.
Colyvan, M. 2008. Is Probability the Only Coherent Approach to Uncertainty? Risk Analysis: 28 (3): 645–52.

EFSA. 2006. Guidance of the scientif ic committee on a request from EFSA related to uncertainties in dietary exposure assessment.

EFSA. 2007. EFSA's 10th Scientific Colloquium. Pest risk assessment - Science in support of phytosanitary decision making in the European Community. Summary Report. Dece mber 6-7, 2007. Parma, Italy.

Falkow, S. 2004. Molecular Koch’s postulates applied to bacterial pathogenicity--a personal recollecti on 15 years later. Nature Reviews Microbiology 2:67-72.
Follett, P.A., and L. G. Neven. 2006. Current trends in quarantine entomology. Annual Review Of Entomology. 51:359-385
Haimes, Y.Y. 2009. On the complex definition of risk: a systems based approach. Risk Analysis 29 (12): 1647-1654.
Hellman, J. J., Byers, J. E., Bierwagen, B. G. and Dukes, J. S. 2008. Five potential consequences of climate change for invasi ve species. Conservation Biology 22(3): 534-543.

IPPC. 1997. International Plant Protection Convention. New Revised Text approved by the FAO Conference at its 29th Session - November 1997.
IPPC. (1998) International Standards fo r Phytosanitary Measures, Publication No. 8: Determination of pest status in an area. Secretariat of the International Plant Protection Convention (IPPC), Food and Agriculture Organization of theSupplements and References Literature Cited

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### United Nations, Rome, Italy.

IPPC. 1999. International Standards for Phytosanitary Meas ures, Publication No. 10: Requirements for the establishm ent of pest free places of production and pest free production si tes. Secretariat of the In ternational Plant Protection Convention (IPPC), Food and Agriculture Organization of th e United Nations, Rome, Italy.

IPPC. 2002. International Standards for Phytosanitary Meas ures, Publication No. 14: The use of integrated measures in a systems approach for pest risk management. Secretariat of the International Plant Protection Convention (IPPC), Food and Agriculture Organization of the United Nations,, Rome, Italy.

IPPC. 2004a. International Standards for Phytosanitary Measures, Publication No. 11: Pest risk analysis for quarantine pests including analysis of environmental risks and living modifi ed organisms. Secretariat of the International Plant Protection Conve ntion (IPPC), Food and Agriculture Organization of the United Nations, Rome, Italy.

IPPC. 2004b. International Standards for Phytosanitary Meas ures, Publication No. 21: Pest risk analysis for regulatednon-quarantine pests. Secretariat of the International Plant Protection Conve ntion (IPPC), Food and Agriculture Organization of the United Nations, Rome, Italy.

IPPC. 2006. International Standards for Phytosanitary Meas ures, Publication No. 1: Phytosanitary principles for the protection of plants and the application of phytosanitary measures in intern ational trade. Secretariat of the International Plant Protection Conve ntion (IPPC), Food and Agriculture Organization of the United Nations, Rome, Italy.

IPPC. 2007. International Standards for Phytosanitary Meas ures, Publication No. 2: Framework for pest risk analysis . Secretariat of the International Plant Protection Convention (IPPC), Food an d Agriculture Organization of the United Nations, Rome, Italy.

IPPC. 2012. International Standards for Phytosanitary Meas ures, Publication No. 5: Glossary of phytosanitary terms. 

### Secretariat of the International Plant Protection Convention (IPPC), Food an d Agriculture Organization of the United Nations, Rome, Italy.
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### MAF. 2008. Import risk analysis: Fres h Coconut (Cocos nucifera) from Tuvalu: Draft for public consultati on. MAF Biosecurity. Wellington, New Zealand 127 pp.
Magarey, R. D., Borchert , D. M. and Schlegel, J. W. 2008. Global plant hardiness zones for phytosanitary risk an alysis. Scientia Agricola 65(Special Issue): 54-59.

NAPPO. 2008. RSPM No. 30: Guidelines for the Determination and Designation of Host Status of a Fruit or Vegetable for Fruit Flies (Diptera: Tephritidae). North Am erican Plant Protection Organization (NAPPO) Regional Standard for Phytosanitary Measures (RSPM).
NAPPO. 2012. Climate change and pest ri sk analysis. North American Plant Protection Organization (NAPPO) discu ssion. PP No. 11. Approved February 29, 2012. Ottawa, Canada.
PPQ. 2000. Guidelines for pathway-initiated pest risk assessments 

### (Version 5.02). United States Department of Agriculture, Animal and Plant Health Inspection Service, Plant Protection and Quarantine (PPQ), Riverdale, MD. 30 pp.
Shurtleff, M. C., and C. W. Averre. 1997. Glossary of Plant-Pathological Terms. APS Press, The American Phytopathology Society, St. Paul, MN.
SPS WTO. 1995. The WTO Agreement on th e Application of Sanitary and Phytosanitary Measures (S PS Agreement). World Trad e Organization, Geneva, Switzerland.
Worner, S. P. 1998. Some problems and approaches to modeling insect phenology. Population and Community Ecology for Insect Management and Conservation (eds. P. Baumgartner, Brandm ayr, and B. J. F. Manly), pp. 89-98, AA Balkema, Rotterdam.