Phytophthora ramorum

P. ramorum is a fungus-like pathogen which can attack a wide range of trees and other plants.

P. ramorum in Northern Ireland

It was confirmed for the first time in Northern Ireland in rhododendron plants in the nursery trade in late 2002. In August 2010 the first confirmation of the disease in Japanese larch was made in a plantation on the Antrim plateau.

Aerial surveillance of public and private forests is carried out twice a year in June and September with follow up ground inspections of suspect cases. Phytophthora ramorum has been identified in larch in all six counties. It has also been identified in other plant species.

There have been 1,000 hectares of larch trees affected to date, with felling still underway in a number of forests. Further action will be taken forward on a prioritised basis.

Phtophthora ramorum sites 2010 - 2017


Tree disease can be spread in many ways, including:

  • on footwear
  • on vehicle wheels
  • on tools and machinery
  • by the movement of infected plants
  • in rain, mists and air currents

If you’re visiting a forest, please pay attention to signs showing what you can do to help prevent spread of the disease. These include:

  • avoiding any action which could result in the movement of infected soil or plant parts to uninfected areas
  • keeping to forest roads
  • keeping dogs on leads
  • removing soil and mud from shoes and boots before leaving the woodland

Reporting suspect symptoms

If you are concerned about symptoms in trees or plants please contact DAERA on 0300 200 7847 or email You can also report suspect symptoms using a smartphone. Go to and complete the form.

Affected timber

Processing affected timber

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