The PPQ Weed Risk Assessment An Introduction Anthony L. Koop, Leslie Newton, Barney Caton, Lisa Kohl, Larry Fowler USDA-APHIS Meeting the Challenge: Preventing, Detecting & Controlling Invasive Plants University of Washington Botanic Gardens September 16-17, 2014 Expect The Best 1 APHIS regulates weeds • Federal Noxious Weeds • NAPPRA Plants – Not Authorized Pending Pest Risk Analysis. • Noxious Seeds - Contaminants in vegetable and agricultural seed Plant Epidemiology and Risk Analysis Laboratory (PERAL) - Provides the analyses that support regulatory decisions I focus on WRA Expect The Best 2 What is Weed Risk Assessment? WRA: An evaluation of the probability of the entry, establishment, and spread of a plant, and its potential consequences (harm & impacts) Decision making Expect The Best 3 Style of the assessment • Mostly Yes/No questions; a few multiple choice • Record uncertainty: negligible, low, moderate, high, max • Evidence, supporting documents, and reasoning are recorded for each Expect The Best 4 Risk Elements in the WRA • Establishment / Spread Potential (23) • Impact Potential (18) • Geographic Potential (36) • Entry Potential (14) Predictive model Uncertainty Analysis Expect The Best 5 The Final Product 3 - 4 page summary –Background/Initiation –Risk element summary –Data and figures –Discussion/Conclusion References Appendix: questions, answers, uncertainty, and evidence Expect The Best 6 The WRA’s core analyses & results • Risk potential • Uncertainty analysis • Geographic potential Expect The Best 7 1) Risk Potential • Calculate risk scores for Establishment/Spread & Impact of plant species – Higher values indicate greater capacity • Determine the final conclusion – High Risk, Low Risk, or Evaluate Further • Species with moderate scores (EF) secondary screening tool Expect The Best 8 Low Risk Mod Risk / High Risk 5 Eval Further 4.5 4 ■ Species Risk Score 3.5 Invasive Status Major-Invaders Minor-Invaders 3 Non-Invaders Risk Rating 2.5 × High Risk ● Evaluate Further Impact Potential 2 ▲ Low Risk 1.5 1 -20 -15 -10 -5 0 5 10 15 20 25 Establishment Spread Potential Model Performance (validation dataset, N=102) Accuracy Error Maj- Non- Maj- Non- Invaders Invaders Invaders Invaders Test (True +) (True -) (False +) (False-) US – PPQ WRA 0.941 0.971 0.000 0.000 US - Aus WRA 0.971 0.794 0.088 0.000 Mean (8 other AUS tests) 0.936 0.715 0.164 0.022 • Overall accuracy is higher than the Australian WRA • Non-invader and major-invader performance similar 2) Uncertainty analysis • Summarize & describe uncertainty for each risk element • Evaluate the sensitivity of the risk scores to uncertainty using a Monte Carlo simulation • what would the risk score be if… • N = 5,000 Expect The Best 11 Low Risk Evaluate High Risk Further 5 4.5 4 3.5 3 2.5 High 99.98% EF→High 0.02% Impact Potential 2 EF→EF 0% 1.5 EF→Low 0% Low 0% 1 -20-15-10-50 5 10152025 Establishment Spread Potential 3) Geographic potential • Geo potential evaluated separately • Simple analysis that matches on and overlays •Plant hardiness zones •Annual precipitation •Climate classes Expect The Best 13 Representing areas where all three climatic variables are suitable for its survival 84 Species Assessed with the New Model 5 Evaluate Further Low Risk High Risk 4.5 4 High Risk 3.5 EF-HR EF-EF 3 Low Risk 2.5 Impact Potential 2 1.5 1 -20 -15 -10 -5 0 5 10 15 20 25 Establishment Spread Potential Hippophae rhamnoides •Cultivated in the U.S., naturalized in 2 WY counties •Become invasive in Canadian prairies •Forms dense thickets, N-fixer, alters natural habitats, reduces access Falcaria vulgaris •First reported in 1923 •Few naturalized populations in plains. But in last 10-15 years one population has rapidly expanded. •Forms dense monocultures, root fragments resprout. Difficult to control. Maybe a threat for some grain growers. Geranium lucidum Low Risk Evaluate High Risk Further 5 4.5 4 Species Risk Score 3.5 Simulated Risk •Shade-adapted winter annual Scores •1st recorded 1971 in a cow pasture 3 2.5 High 100% •Dominates forest understories. Impact Potential 2 EF-High 0% EF-EF 0% 1.5 EF-Low 0% •Persistent seed bank Low 0% 1 •Spreading -20 -15 -10 -5 0 5 10 15 20 25 Establishment Spread Potential Austroderia richardii Low Risk Evaluate High Risk 5 Further •New Zealand grass similar & 4.5 closely related to Cortaderia 4 3.5 •Naturalized in Tasmania & the U.K. 3 2.5 •Little detailed info on impacts; but it High 87.5% Impact Potential 2 EF-High 9.7% ranked high on perceived impacts. EF-EF 2.8% 1.5 EF-Low 0% Low 0% 1 -20-15-10-50 5 10152025 Establishment Spread Potential Leptochilus pteropus •Aquatic ornamental •Tropical / subtropical fern species •No evidence of impact or invasiveness elsewhere. Working Together Many potential weeds What we can do for you – Share completed WRAs – Train & mentor you [WRA-101 (Feb 24-27, 2015)] What you can do for us – Tell us about new and emerging weed threats – Identify weeds not yet in the U.S. that could be problematic Expect The Best 21 For more information or to submit requests for WRA Tony Koop Plant Epidemiology and Risk Analysis Laboratory Center for Plant Health Science and Technology USDA - APHIS – PPQ 1730 Varsity Drive, Suite 300 Raleigh, NC 27606-5202 Phone: (919) 855-7429 Email: [email protected] Barney Caton (PERAL Asst. Dir.) – [email protected] Expect The Best 22.