31 Aug 2022

Over one million hectares surveyed for tree diseases

Scottish Forestry’s tree health team has surveyed over one million hectares of forest this year as part of their efforts to monitor the health of our woodlands.

Along with keeping alert for a range of other tree pests and diseases, the agency’s tree health experts are keeping a watchful eye on larch trees which are under attack from a disease called Phytophthora ramorum.

This disease has been found in Scotland since 2002 on a range of species in horticultural settings. Since 2009 it has increasingly affected forests containing larch in the south and west of Scotland, where the wetter and warmer climate is known to be favourable for the disease.

As a result of the actions set out in the current P. ramorum Action Plan, the disease appears to be under control across most of Scotland.

James Nott, Head of Tree Health for Scottish Forestry said

“With over two thirds (over 40,000 hectares) of Scotland’s larch resource still unaffected by P. ramorum, management efforts will continue to be concentrated in the Priority Action Zone (PAZ) of eastern and northern Scotland. Surveys in these areas have demonstrated clearly that swift felling of affected trees is an effective and realistic control method.

“In the areas of the south and west of Scotland, where the disease has been established for a number of years, forest managers are taking a more strategic approach to managing the disease, and are encouraged to use proactive management through the forest plan process.

“The efforts across the sector in tackling this disease is a credit to the range of professionals involved.”

The main surveillance programme is run by Scottish Forestry with the support of Forestry and Land Scotland and Forest Research. However, citizen science is also proving to be very useful with nearly a quarter of the survey sites in the Priority Action Zone being reported to Scottish Forestry by foresters and interested members of the public. This continues the trend of increasing numbers of reports from previous years.

Across Scotland a total of 613 larch sites have so far been identified for field survey in 2022, with 67 reports from forest owners and managers.

After review by a group of stakeholders and scientific advisers, including representatives from CONFOR, Forest Research, FLS and Scotland’s Chief plant health officer, the current controls set out in 2020/2021 will remain unchanged.

Mr Nott added:

“We can all do our bit to help stop pests and diseases spreading, whether you are a forester or a member of the public. Tree diseases can be spread on machinery, vehicles, clothing, bike tyres and even on dogs paws, so everyone should Keep it Clean before visiting a forest.”

More information, including the updated map on disease spread and a link to the Scottish Forestry larch action plan can be found here