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USDA-APHIS-PPQ 

Potentially Actionable Suspect Sample Policy: 

Phytophthora ramorum

Overview

A Potentially Actionable Suspect Sample (PASS) is a regulatory sample where preliminary diagnostics indicate a USDA 

regulatory pathogen is present and requires confirmation by the USDA APHIS PPQ Plant Pathogen Confirmatory 

Diagnostic Laboratory (PPCDL). 

Samples Collected from a Non-Quarantine Area or Non-Regulated Establishment

Any regulatory sample collected from a non-quarantine area or non-regulated establishment that tests positive or 

inconclusive for P. ramorum by a PPDCP certified diagnostician using the APHIS approved Screening Work 

Instructions is considered a PASS and must be forwarded to the USDA APHIS PPQ S&T-PPCDL for final determination. 

Sample should consist of symptomatic plant material and DNA. 

USDA-APHIS-PPQ-S&T PPCDL

Sample Diagnostics 

9901 Powder Mill Road 

BARC-East, Bldg. 580

Laurel, MD 20708 

Phone: (301) 313-9208 or (301) 313-9223

When forwarding materials notify the lab at: APHIS-PPQCPHSTBeltsvilleSampleDiagnostics@usda.gov. You must 

include number of samples and tracking information in this communication. Do not ship samples on Fridays or the 

day before a federal holiday. 

Samples Collected from a Quarantined Area or Regulated Establishment

A regulatory sample collected in a quarantined area or regulated establishment that tests positive for P. ramorum by

a PPDCP Certified diagnostician using the APHIS approved Screening Work Instructions is considered a PASS and 

must be forwarded to the USDA APHIS PPQ S&T-PPDCL for final determination under the following conditions: 

 The sample is the first positive from a certified nursery or a nursery seeking certification in a Quarantined Area.

 The sample is an unusual detection (novel symptoms or new host).

A regulatory sample collected in a quarantined area or regulated establishment that does not follow the condition 

stated above is a non-PASS. A PPDCP certified diagnostician has the authority to make the final determination on a 

regulatory sample collected from a quarantined area or regulated establishment (previously confirmed positive by APHIS 

PPQ S&T) if: 

 The laboratory notifies both the APHIS National Policy and National Operations Managers of the positive within

24 hours of the diagnostic result.

 APHIS and the state are in concurrence on the list of previously positive regulated areas or establishment within

the state.

A regulatory sample (either PASS or non-PASS) that tests inconclusive for P. ramorum by a PPDCP Certified 

Diagnostician using the APHIS approved Screening Work Instructions must be forwarded to the USDA-APHIS-PPQ 

Plant Pathologist - Domestic Identifier Laboratory (PPDIL) for further testing. Under certain circumstances, the 

diagnostician may be instructed by PPQ to forward PASS inconclusive samples directly to the PPCDL for processing.

USDA-APHIS-PPQ Field Operations, Kansas State University 

4024 Throckmorton 

Manhattan, KS 66506-5502 

Phone: (785) 532-1349, PPQ.Ops.KS.Manhattan.Lab@usda.gov

USDA-APHIS-PPQ PASS Policy for P. ramorum; last modified March 20, 2024
USDA-APHIS-PPQ

Potentially Actionable Suspect Sample Policy: 

Phytophthora ramorum

USDA-APHIS-PPQ PASS Policy for P. ramorum; last modified March 20, 2024 Page 2 of 2

Definitions

Non-PASS (Potentially Actionable Suspect Sample): Are all subsequent samples from a nursery or area that APHIS 

confirmed positive for P. ramorum. A PPDCP certified diagnostician outside of APHIS can make the final determination 

using PPCDL diagnostic work instructions. For a nursery that has been historically positive, all samples are 

“non-PASS” if tested by the PPDCP certified diagnostician. 

PPDCP certified diagnostician: A person recognized by APHIS through the Plant Pathogen Diagnostic Certification 

Program as possessing all the necessary equipment and certified personnel to perform P. ramorum screening tests using 

the current APHIS work instructions. 

Potentially Actionable Suspect Sample (PASS): Presumptive positive P. ramorum sample that requires confirmatory 

testing by an official APHIS Laboratory due to the nature of the plant sampled and the necessity for Federal 

confirmation. That is, a sample from a new state, new county, new nursery, new host that is not on the APHIS list, or a 

novel symptom. 

Quarantine Area: Any area where P. ramorum has been found and officially confirmed in the natural environment. 

Regulated Establishment: Any APHIS recognized area or establishment where P. ramorum has been federally 

confirmed. 

Regulatory Sample: This is a sample of regulatory concern to APHIS for P. ramorum collected by regulatory officials.