NEW legislation has been introduced to allow the movement of large oak trees and trade within the operational zones and boundaries in place to help manage oak processionary moth (OPM).

The tree pest, first identified in London in 2006, has spread to some surrounding counties in the South-East of England. Its caterpillars feed on the leaves of several species of oak trees, causing them to lose their leaves, negatively impacting their growth, and making them more vulnerable to other stresses, such as drought. When touched, they can cause itchy rashes and eye and throat irritations. The period between June and August provides the greatest risk to health as this is when the caterpillars emerge.

READ MORE: OPM buffer zones extended once again to cover English counties

The Forestry Commission has in place operational zones and boundaries aimed at managing OPM. In March, in response to government surveillance, the established area in which OPM is established, and the buffer zone, in which an annual programme of OPM management takes place, were expanded.

A new demarcated area will be established around the buffer zone and established area, enabling large oak trees (girth at 1.2 m above the root collar of 8 cm or more) to be moved within this boundary, provided the trees are moved by professional operators and that biosecurity requirements are met along with movement restrictions.

Professor Nicola Spence, UK chief plant health officer, said: “Healthy oak trees are a vital component of a biodiverse and thriving environmental landscape. They are Great Britain’s most important tree for species biodiversity, supporting over 2000 species of bird, mammal, fungi, invertebrate, bryophyte and lichen.

“This is why it is essential that to protect the health of our oak trees, we have regulations in place for the movement of large oak trees within the zones and boundaries designed to manage oak OPM.”

Andrew Hoppit, OPM project manager, said: “While we understand the importance of professional operators being able to move large oak trees, it is vital that we have in place stringent biosecurity requirements to ensure a risk-based approach for moving these trees.”

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Large oak trees will be able to be moved within the established area, or into the established area from the buffer zone, providing the following biosecurity requirements are met:

  • Biosecurity competence: professional operators must demonstrate that they meet the Plant Health Management Standard evidenced through membership of the Plant Healthy Certification Scheme or provision of a Ready to Plant approval from Fera Science for each consignment to be moved.
  • Official inspections: professional operators must keep accurate records of the contact details of those receiving large oak trees, including the delivery address.
  • Large oak trees will be able to be moved within the buffer zone if they meet two additional biosecurity requirements:
  • Phytosanitary treatments: professional operators must have a robust control regime in place with appropriate phytosanitary treatments, which must be applied in line with DEFRA guidance on application of phytosanitary treatments for the control of OPM (Thaumetopoea processionea) 2023.
  • Post-planting inspections: professional operators must disclose the potential for post-planting inspection as part of the new legislation to buyers at the time of purchase. A proportion of high-risk large oak movements within the buffer zone will be subject to post-planting inspections by the plant health inspectors.

Professional operators who are growing or moving large oak trees, and who are impacted by the new movement restrictions, should consult with their local plant health inspector or the Plant Health and Seeds Inspectorate for further advice.