News, stories and reports from Forestry Commission Scotland and the National Forest Estate

Plant health round-up

The risk of exotic pests and diseases arriving in Scotland is amplified with increasing globalisation, whilst future climate changes could increase the risk of their establishment, spread and impact.

Phytophthora ramorum, Dothistroma needle blight and Chalara dieback of ash remain the highest profile tree health issues in Scotland, and Action Plans for them remain under regular review. Other pests and diseases under close monitoring and management action include pine tree lappet moth and the great spruce bark beetle.

Constant vigilance against new threats, together with continued co-ordinated action to manage existing pests and diseases, is essential if Scotland’s forests are to remain economically, environmentally and socially sustainable. 

scotts view sunrise

Plant Health in Scotland and across the EU

Along with the Scottish Government Plant Health team, FCS is part of the UK Plant Health Service, ensuring an integrated cross-border approach to tree health management. 

Published in March 2016, the Scottish Plant Health Strategy outlines Scottish Government’s approach to the protection of the health of plants (including forestry and the natural environment). Emphasising the importance of safeguarding Scottish plant health to protect and enhance Scotland’s economy and natural environment, the Strategy sets out how Scotland will take forward the Plant Biosecurity Strategy for Great Britain, ensuring that Scottish Government and stakeholders work together to protect plant health in Scotland. 

The Scottish Tree Health Advisory Group continues to provide a useful stakeholder engagement mechanism, ensuring that pest and disease threats and management measures are well understood, and continue to be proportionate. A revised generic Plant Health Contingency Plan for Scotland, coupled with pest/disease specific contingency plans, has further enhanced our tree health readiness.  

A new Plant Health Regulation entered into force in December 2016, to be implemented by December 2019.  Replacing the EU's Plant Health legislation (which had been in place since 1977), the new regulation aims to strengthen plant health biosecurity and provide greater protection against the introduction and spread of plant pests and diseases using a risk-based and proportionate approach.

Continuing to slow the spread and impact of Phytophthora ramorum

In 2016, the annual Tree Health surveillance and monitoring programme resulted in 71 new findings of Phytophthora ramorum on larch and a further 61 sites with infected Rhododendron within the wider woodland environment.  These findings included the first known records of this disease on larch in the Cairngorms and Loch Lomond & the Trossachs National Parks, as well as a number of findings outside the most climatically suitable area for P. ramorum.  However, all these outbreaks were relatively small in scale, and our early detection ensured swift action via statutory measures.  As the disease has only been detected in c. 1% of larch woodland outwith the south west Scotland Management Zone, statutory control measures will remain in place to help slow down the rate of disease spread and severity. The detection of the disease in lower risk areas also highlighted the importance of all woodland owners and visitors remaining vigilant and implementing the biosecurity practices recommended in the Scottish Government ‘Keep it Clean' campaign.  


Management of the great spruce bark beetle

As part of the surveillance programme, 53 new Dendroctonus micans (Great spruce bark beetle) sites were also confirmed in 2016: all in south-west Scotland.  The vast majority were either treated with the biocontrol Rhizophagusgrandis to help minimise impact of this pest, or were in areas where this predator is already present.  There has been a gradual northerly spread of findings of this pest over the last two years and it is now closer to the ‘pest free area’ in north-west Scotland; currently exports of Spruce with bark can be made to Ireland (where the pest is not known to be present) from this area.  We will continue to work with the industry (particularly the timber transport sector) and Forest Research to try and ensure minimal impacts to the health of spruce.


Protecting our Caledonian pinewoods

Conserving our Caledonian pinewoods in the face of tree health threats remains a high priority. However, the nursery sector and those involved with woodland expansion raised legitimate concerns about initial FCS guidance on Dothistroma needle blight (2013) that included a presumption against direct planting Scots pine within 600m of Caledonian Pinewood Inventory sites. Following a risk review, revised guidance (2017) now allows the planting of Scots pine where natural regeneration has been unsuccessful and where there is an agreed and urgent need for action.