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Oak processionary moth - control plan 2016

OPM Pilot Extension 2016: Summary of proposed operational activity


This paper provides an overview of the OPM Control Programme for 2016. It includes details on surveillance, control, communications and liaison.

Introduction and Context

Since 2013 the Forestry Commission has been implementing a pilot control programme for OPM. This Defra-funded pilot has been extended for a further year for 2016. Although this year’s work is broadly similar to that of previous pilot years, plans have been adapted to take account of findings over recent years and improvements in our understanding of OPM management. The proposals in this paper are based on our current understanding of OPM extent, which we expect to change over the year. Therefore we expect this plan might be adjusted in light of new findings. There might also be adjustments made as we build our knowledge in response to the latest evidence.

Objectives for 2016

The main policy objective is to limit the rate of spread of OPM from existing known areas of infestation, and to suppress population levels within infested areas to limit the impact of OPM. This work will further develop our understanding of OPM population distribution, the best approaches to surveillance and control and provide evidence to inform the development of future policy.

Legal Considerations

Statutory Plant Health Notices (SPHNs) will be issued to all affected landowners outside the core zone defined for 2016. However, we may issue SPHNs to landowners within the core zone where infestations pose a significant threat to the buffer (control) zone. We will identify which owners will and will not receive funding support. A new SPHN and covering letter and guidance will be issued to help landowners on the actions which need to be taken.

Budget / resource allocation

The budget will be prioritised in line with the programme objectives, with resources focused on surveillance activities, control work (spraying and nest removal), research and communications.

Principles behind budget allocations for each area:

• Pangbourne – continued surveillance is required, as we continue to trap male moths, and are keen to ensure that the apparent success is secured.

• East London – eradication is the objective for this area; it is a relatively small-scale outbreak with limited numbers of oak trees, so surveillance and control costs should be low.

• Croydon/Bromley – we appear to have had some success in 2015 in limiting the spread, pushing it back in the southern part of the outbreak. Work and budget are based on a similar level of surveillance and control as 2015.

• Guildford – Subject to continuing survey work, but the intention is to survey and control known infestations in line with other outbreak areas.

• Main London Area – continued surveillance and control, but focussed on the outer edge, and activity will be targeted.

Activity plans

Visual surveillance
A visual survey will be carried out of trees known to be infested in 2014 and 2015, as well any within 100 metres of those trees. A visual survey of trees will also be carried out within 250m of pheromone traps in which more than five moths were caught in 2015. This will be reviewed in the light of budgetary constraints as the financial year progresses.

We will collaborate with others conducting their own surveys, and encourage wider surveys by others, such as Observatree, Woodland Trust and Tree Wardens, to look out for ‘satellite’ infestations.

Pheromone Trapping
There will be about 1500 traps deployed in 2016, covering previous areas and extending coverage further away from known infestations. As well as determining flight extent, the aim is to continue analysing trap data against survey and control activity to see what the relationship with traps might be.
We will continue to encourage other landowners to put up traps and monitor them, e.g. Woodland Trust, City of London, Forest Enterprise England, National Trust.

Chemical control
Chemical application of known infested sites in 2014 and 2015, plus host trees within a 50m radius, will be done. The application method will be site-dependent, but seeks to balance control effectiveness with other impacts.

Nest Removal
Nest removal will be funded in all areas outside the core zone, based on summer survey findings, and subject to budget availability. Nest removal after moth emergence will not be funded or required under SPHNs on the basis that it will not affect spread, and that not doing it will increase scope for the development of OPM parasitoids.


Communications will continue to focus on raising awareness, encouraging vigilance and collaboration, reporting sightings and targeted messaging at key points in the season e.g. larval emergence, when they become a public health risk, and nest building. Regular updates on progress and OPM findings through the season will be provided via email and on the FC website. A complete picture of progress relies on the provision of OPM information from others.


The OPM Advisory Group will remain a key means of sharing information and gaining feedback on the programme. It will be reviewed to ensure that membership reflects the geographic distribution of OPM. Specific liaison activity will be done in outbreak areas.


Last updated: 14th June 2017