Scenario analysis for the risk of pine shoot beetle outbreaks resulting from the movement of pine logs from regulated areas

76 Pages·1994·2.9 MB·English

by  United States. Animal and Plant Health Inspection Service

Historic, Archive Document
Do not assume content reflects current
scientific knowledge, policies, or practices.

DRAFT
Scenario Analysis for the
Risk of Pine Shoot Beetle Outbreaks
Resulting from the Movement of
Pine Logs from Regulated Areas
U.S. Department of Agriculture
Animal and Plant Health Inspection Service
December 1994

Contents:
Background Pages 1-4
Pestand Objective
PestDistribution
Backgroundonthe Situation
BackgroundonthePest
AssessmentMethodology
Figure Diagram ofCombined Scenarios
1:
Probability andFrequencyEstimates Pages 5-15
IntroductiontoProbabilityData
AssumptionsandDefinitionofSeasons
General Information
Frequencyand ScenarioProbability Summary Discussion
Analysis Pages 16-27
Table 1: CombinedProbabilityEstimates - All Scenarios
& D
Scenarios A, B, C,
Individual ScenarioswithTablesofEstimates and Point Products
Probability DistributionCurves
Table2: FrequencyofOutbreaksby Season and YearsperOutbreak
Table 3: PercentRiskby Scenarioand Season
Figure 2: ComparativeRiskBasedonMode Values
Table4: Sub-scenarioRankingby RiskBasedonMode Values
RiskManagement Pages 29-32
MitigationDiscussion
Listingof Potential RiskManagement Recommendations
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Table5: Potential Treatment Measures
Table6: Mitigation Applications
Appendix Pages33-34
I. ReferencesandEvidence
II. Assessors andExperts
I
Scenario Analysis for the Risk of Pine Shoot Beetle Outbreaks Resulting
from the Movement of Pine Logs from Regulated Areas
Pest: Tomicus =Blastophagus piniperda (L.)
( )
Coleoptera: Scolytidae (Bark Beetles)
Common Name: Pine Shoot Beetle (PSB)
Objective:
A quantitative characterization ofthe risks associated with the movement ofpine logs from
regulated areas and to identify the best combination ofavailable mitigation measures that
effectively reduce the risk ofartificial spread to acceptable levels while also relieving the
regulatory burden on the logging industry as much as reasonably possible. The product ofthis
effort will provide the basis for changes in PPQ domestic quarantine regulations.
Pest Distribution: Europe, Asia, and the Great Lakes region ofthe United States
Background on the Situation:
PSB was discovered near Cleveland, Ohio in July 1992. It is now known to be established in six
States: Illinois, Indiana, Michigan, New York, Ohio, and Pennsylvania. It is expected to continue
spreading naturally.
Infested counties are currently regulated under Federal and State quarantines. At present, logs of
pine trees can be transported from infested counties to non-infested areas from July 1 through
October 31 with no restriction (most beetles are assumed to be in the shoots during this time -
normal logging practice would remove all branches from the logs before moving to the sawmill).
From November 1 through June 30, logs must be fumigated or processed at the destination within
24 hours ofharvest (beetles are overwintering at the base ofthe tree during this time - the
assumption is that beetles are destroyed during debarkin^processing at the sawmill).
Early in 1994, the Michigan Dept, ofAgriculture (MDA) proposed modifications to the current
regulatory regime. PPQ rejected the proposal, resulting in a continuing discourse with MDA,
PPQ, and the Forest Service about technical aspects ofthe proposal, options, and risk.
This document has been developed by PPQ to characterize the risks as the basis for
decisionmaking associated with a regulatory proposal for changes in the existing regulations.
Scenario analysis has been offered as a methodology that could be used to evaluate the variables
contributing to the pest risk and to identify the options to mitigate the risk.
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