EPPO Platform
on PRAs

Assessing the confidence in pest freedom gained in the past pine wood nematode surveys


All Member States of the European Union must conduct annual surveys of pine wood nematode (PWN) to ensure its timely detection. However, the statistical confidence of these surveys is rarely assessed. To facilitate such assessments, we developed two easy‐to‐use web applications: NoBaSURV‐PWN for assessment of the statistical confidence of past PWN surveys, and NoBa Land Cover Retriever for retrieving the land cover data needed in the assessments. This report explains how the statistical confidence of past PWN surveys can be assessed with NoBaSURV‐PWN. In addition, the report presents the assessments done with the NoBaSURV‐PWN application for Estonia, Finland, Lithuania, Norway, and Sweden. The technical details of the developed applications are presented, and some matters that have general relevance for statistical assessment and planning of quarantine pest surveys are discussed. Also, the capacity building activities done in the project are described and their impact is evaluated. The assessments for the five Nordic‐Baltic countries show that, in most of the countries, PWN surveys have been extensive enough to provide evidence for facilitating trade with a rather high confidence. Yet, the surveys have clearly not been extensive enough to ensure detection of PWN invasions at such an early stage that they could be eradicated.


  • Bursaphelenchus xylophilus


  • Picea abies
  • Pinus sylvestris


Type File Size
Pest Risk Analysis Download 2,49MB

PRA Area

  • Estonia
  • Finland
  • Lithuania
  • Norway
  • Sweden