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Pine wood nematode (Bursaphelenchus xylophilus)

Pinewood nematodes in a water droplet

Pine wood nematode (PWN), Bursaphelenchus xylophilus, is regarded as a major threat to European forests, particularly following its establishment in Portugal and the fact that, even with the application of stringent measures, the pest has continued to spread and kill pine trees in that country.

The basis for classifying PWN as a highly significant threat is well documented and its track record of killing pine trees in:

  • Japan (where tree deaths were noted in the 19th century, but the nematode as causal agent was only confirmed in the late 1960s)
  • China (from 1982)
  • Korea (from 1988)
  • Taiwan (from 1985)
  • Portugal (continental PT 1999 and Madeira 2009)
  • Spain (2008) - a single infested tree.

In all countries where wilt expression has been recorded (leading to the description of the syndrome pine wilt disease) there has been extensive tree mortality.

A contingency planwill ensure government agencies make a rapid and effective response to any outbreak of the pest in Britain.

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Last updated: 23rd November 2017